window.rs

   1#[cfg(any(feature = "inspector", debug_assertions))]
   2use crate::Inspector;
   3use crate::{
   4    Action, AnyDrag, AnyElement, AnyImageCache, AnyTooltip, AnyView, App, AppContext, Arena, Asset,
   5    AsyncWindowContext, AvailableSpace, Background, BorderStyle, Bounds, BoxShadow, Capslock,
   6    Context, Corners, CursorStyle, Decorations, DevicePixels, DispatchActionListener,
   7    DispatchNodeId, DispatchTree, DisplayId, Edges, Effect, Entity, EntityId, EventEmitter,
   8    FileDropEvent, FontId, Global, GlobalElementId, GlyphId, GpuSpecs, Hsla, InputHandler, IsZero,
   9    KeyBinding, KeyContext, KeyDownEvent, KeyEvent, Keystroke, KeystrokeEvent, LayoutId,
  10    LineLayoutIndex, Modifiers, ModifiersChangedEvent, MonochromeSprite, MouseButton, MouseEvent,
  11    MouseMoveEvent, MouseUpEvent, Path, Pixels, PlatformAtlas, PlatformDisplay, PlatformInput,
  12    PlatformInputHandler, PlatformWindow, Point, PolychromeSprite, Priority, PromptButton,
  13    PromptLevel, Quad, Render, RenderGlyphParams, RenderImage, RenderImageParams, RenderSvgParams,
  14    Replay, ResizeEdge, SMOOTH_SVG_SCALE_FACTOR, SUBPIXEL_VARIANTS_X, SUBPIXEL_VARIANTS_Y,
  15    ScaledPixels, Scene, Shadow, SharedString, Size, StrikethroughStyle, Style, SubpixelSprite,
  16    SubscriberSet, Subscription, SystemWindowTab, SystemWindowTabController, TabStopMap,
  17    TaffyLayoutEngine, Task, TextRenderingMode, TextStyle, TextStyleRefinement, ThermalState,
  18    TransformationMatrix, Underline, UnderlineStyle, WindowAppearance, WindowBackgroundAppearance,
  19    WindowBounds, WindowControls, WindowDecorations, WindowOptions, WindowParams, WindowTextSystem,
  20    point, prelude::*, px, rems, size, transparent_black,
  21};
  22use anyhow::{Context as _, Result, anyhow};
  23use collections::{FxHashMap, FxHashSet};
  24#[cfg(target_os = "macos")]
  25use core_video::pixel_buffer::CVPixelBuffer;
  26use derive_more::{Deref, DerefMut};
  27use futures::FutureExt;
  28use futures::channel::oneshot;
  29use gpui_util::post_inc;
  30use gpui_util::{ResultExt, measure};
  31use itertools::FoldWhile::{Continue, Done};
  32use itertools::Itertools;
  33use parking_lot::RwLock;
  34use raw_window_handle::{HandleError, HasDisplayHandle, HasWindowHandle};
  35use refineable::Refineable;
  36use scheduler::Instant;
  37use slotmap::SlotMap;
  38use smallvec::SmallVec;
  39use std::{
  40    any::{Any, TypeId},
  41    borrow::Cow,
  42    cell::{Cell, RefCell},
  43    cmp,
  44    fmt::{Debug, Display},
  45    hash::{Hash, Hasher},
  46    marker::PhantomData,
  47    mem,
  48    ops::{DerefMut, Range},
  49    rc::Rc,
  50    sync::{
  51        Arc, Weak,
  52        atomic::{AtomicUsize, Ordering::SeqCst},
  53    },
  54    time::Duration,
  55};
  56use uuid::Uuid;
  57
  58mod prompts;
  59
  60use crate::util::atomic_incr_if_not_zero;
  61pub use prompts::*;
  62
  63/// Default window size used when no explicit size is provided.
  64pub const DEFAULT_WINDOW_SIZE: Size<Pixels> = size(px(1536.), px(864.));
  65
  66/// A 6:5 aspect ratio minimum window size to be used for functional,
  67/// additional-to-main-Zed windows, like the settings and rules library windows.
  68pub const DEFAULT_ADDITIONAL_WINDOW_SIZE: Size<Pixels> = Size {
  69    width: Pixels(900.),
  70    height: Pixels(750.),
  71};
  72
  73/// Represents the two different phases when dispatching events.
  74#[derive(Default, Copy, Clone, Debug, Eq, PartialEq)]
  75pub enum DispatchPhase {
  76    /// After the capture phase comes the bubble phase, in which mouse event listeners are
  77    /// invoked front to back and keyboard event listeners are invoked from the focused element
  78    /// to the root of the element tree. This is the phase you'll most commonly want to use when
  79    /// registering event listeners.
  80    #[default]
  81    Bubble,
  82    /// During the initial capture phase, mouse event listeners are invoked back to front, and keyboard
  83    /// listeners are invoked from the root of the tree downward toward the focused element. This phase
  84    /// is used for special purposes such as clearing the "pressed" state for click events. If
  85    /// you stop event propagation during this phase, you need to know what you're doing. Handlers
  86    /// outside of the immediate region may rely on detecting non-local events during this phase.
  87    Capture,
  88}
  89
  90impl DispatchPhase {
  91    /// Returns true if this represents the "bubble" phase.
  92    #[inline]
  93    pub fn bubble(self) -> bool {
  94        self == DispatchPhase::Bubble
  95    }
  96
  97    /// Returns true if this represents the "capture" phase.
  98    #[inline]
  99    pub fn capture(self) -> bool {
 100        self == DispatchPhase::Capture
 101    }
 102}
 103
 104struct WindowInvalidatorInner {
 105    pub dirty: bool,
 106    pub draw_phase: DrawPhase,
 107    pub dirty_views: FxHashSet<EntityId>,
 108}
 109
 110#[derive(Clone)]
 111pub(crate) struct WindowInvalidator {
 112    inner: Rc<RefCell<WindowInvalidatorInner>>,
 113}
 114
 115impl WindowInvalidator {
 116    pub fn new() -> Self {
 117        WindowInvalidator {
 118            inner: Rc::new(RefCell::new(WindowInvalidatorInner {
 119                dirty: true,
 120                draw_phase: DrawPhase::None,
 121                dirty_views: FxHashSet::default(),
 122            })),
 123        }
 124    }
 125
 126    pub fn invalidate_view(&self, entity: EntityId, cx: &mut App) -> bool {
 127        let mut inner = self.inner.borrow_mut();
 128        inner.dirty_views.insert(entity);
 129        if inner.draw_phase == DrawPhase::None {
 130            inner.dirty = true;
 131            cx.push_effect(Effect::Notify { emitter: entity });
 132            true
 133        } else {
 134            false
 135        }
 136    }
 137
 138    pub fn is_dirty(&self) -> bool {
 139        self.inner.borrow().dirty
 140    }
 141
 142    pub fn set_dirty(&self, dirty: bool) {
 143        self.inner.borrow_mut().dirty = dirty
 144    }
 145
 146    pub fn set_phase(&self, phase: DrawPhase) {
 147        self.inner.borrow_mut().draw_phase = phase
 148    }
 149
 150    pub fn take_views(&self) -> FxHashSet<EntityId> {
 151        mem::take(&mut self.inner.borrow_mut().dirty_views)
 152    }
 153
 154    pub fn replace_views(&self, views: FxHashSet<EntityId>) {
 155        self.inner.borrow_mut().dirty_views = views;
 156    }
 157
 158    pub fn not_drawing(&self) -> bool {
 159        self.inner.borrow().draw_phase == DrawPhase::None
 160    }
 161
 162    #[track_caller]
 163    pub fn debug_assert_paint(&self) {
 164        debug_assert!(
 165            matches!(self.inner.borrow().draw_phase, DrawPhase::Paint),
 166            "this method can only be called during paint"
 167        );
 168    }
 169
 170    #[track_caller]
 171    pub fn debug_assert_prepaint(&self) {
 172        debug_assert!(
 173            matches!(self.inner.borrow().draw_phase, DrawPhase::Prepaint),
 174            "this method can only be called during request_layout, or prepaint"
 175        );
 176    }
 177
 178    #[track_caller]
 179    pub fn debug_assert_paint_or_prepaint(&self) {
 180        debug_assert!(
 181            matches!(
 182                self.inner.borrow().draw_phase,
 183                DrawPhase::Paint | DrawPhase::Prepaint
 184            ),
 185            "this method can only be called during request_layout, prepaint, or paint"
 186        );
 187    }
 188}
 189
 190type AnyObserver = Box<dyn FnMut(&mut Window, &mut App) -> bool + 'static>;
 191
 192pub(crate) type AnyWindowFocusListener =
 193    Box<dyn FnMut(&WindowFocusEvent, &mut Window, &mut App) -> bool + 'static>;
 194
 195pub(crate) struct WindowFocusEvent {
 196    pub(crate) previous_focus_path: SmallVec<[FocusId; 8]>,
 197    pub(crate) current_focus_path: SmallVec<[FocusId; 8]>,
 198}
 199
 200impl WindowFocusEvent {
 201    pub fn is_focus_in(&self, focus_id: FocusId) -> bool {
 202        !self.previous_focus_path.contains(&focus_id) && self.current_focus_path.contains(&focus_id)
 203    }
 204
 205    pub fn is_focus_out(&self, focus_id: FocusId) -> bool {
 206        self.previous_focus_path.contains(&focus_id) && !self.current_focus_path.contains(&focus_id)
 207    }
 208}
 209
 210/// This is provided when subscribing for `Context::on_focus_out` events.
 211pub struct FocusOutEvent {
 212    /// A weak focus handle representing what was blurred.
 213    pub blurred: WeakFocusHandle,
 214}
 215
 216slotmap::new_key_type! {
 217    /// A globally unique identifier for a focusable element.
 218    pub struct FocusId;
 219}
 220
 221thread_local! {
 222    /// Fallback arena used when no app-specific arena is active.
 223    /// In production, each window draw sets CURRENT_ELEMENT_ARENA to the app's arena.
 224    pub(crate) static ELEMENT_ARENA: RefCell<Arena> = RefCell::new(Arena::new(1024 * 1024));
 225
 226    /// Points to the current App's element arena during draw operations.
 227    /// This allows multiple test Apps to have isolated arenas, preventing
 228    /// cross-session corruption when the scheduler interleaves their tasks.
 229    static CURRENT_ELEMENT_ARENA: Cell<Option<*const RefCell<Arena>>> = const { Cell::new(None) };
 230}
 231
 232/// Allocates an element in the current arena. Uses the app-specific arena if one
 233/// is active (during draw), otherwise falls back to the thread-local ELEMENT_ARENA.
 234pub(crate) fn with_element_arena<R>(f: impl FnOnce(&mut Arena) -> R) -> R {
 235    CURRENT_ELEMENT_ARENA.with(|current| {
 236        if let Some(arena_ptr) = current.get() {
 237            // SAFETY: The pointer is valid for the duration of the draw operation
 238            // that set it, and we're being called during that same draw.
 239            let arena_cell = unsafe { &*arena_ptr };
 240            f(&mut arena_cell.borrow_mut())
 241        } else {
 242            ELEMENT_ARENA.with_borrow_mut(f)
 243        }
 244    })
 245}
 246
 247/// RAII guard that sets CURRENT_ELEMENT_ARENA for the duration of a draw operation.
 248/// When dropped, restores the previous arena (supporting nested draws).
 249pub(crate) struct ElementArenaScope {
 250    previous: Option<*const RefCell<Arena>>,
 251}
 252
 253impl ElementArenaScope {
 254    /// Enter a scope where element allocations use the given arena.
 255    pub(crate) fn enter(arena: &RefCell<Arena>) -> Self {
 256        let previous = CURRENT_ELEMENT_ARENA.with(|current| {
 257            let prev = current.get();
 258            current.set(Some(arena as *const RefCell<Arena>));
 259            prev
 260        });
 261        Self { previous }
 262    }
 263}
 264
 265impl Drop for ElementArenaScope {
 266    fn drop(&mut self) {
 267        CURRENT_ELEMENT_ARENA.with(|current| {
 268            current.set(self.previous);
 269        });
 270    }
 271}
 272
 273/// Returned when the element arena has been used and so must be cleared before the next draw.
 274#[must_use]
 275pub struct ArenaClearNeeded {
 276    arena: *const RefCell<Arena>,
 277}
 278
 279impl ArenaClearNeeded {
 280    /// Create a new ArenaClearNeeded that will clear the given arena.
 281    pub(crate) fn new(arena: &RefCell<Arena>) -> Self {
 282        Self {
 283            arena: arena as *const RefCell<Arena>,
 284        }
 285    }
 286
 287    /// Clear the element arena.
 288    pub fn clear(self) {
 289        // SAFETY: The arena pointer is valid because ArenaClearNeeded is created
 290        // at the end of draw() and must be cleared before the next draw.
 291        let arena_cell = unsafe { &*self.arena };
 292        arena_cell.borrow_mut().clear();
 293    }
 294}
 295
 296pub(crate) type FocusMap = RwLock<SlotMap<FocusId, FocusRef>>;
 297pub(crate) struct FocusRef {
 298    pub(crate) ref_count: AtomicUsize,
 299    pub(crate) tab_index: isize,
 300    pub(crate) tab_stop: bool,
 301}
 302
 303impl FocusId {
 304    /// Obtains whether the element associated with this handle is currently focused.
 305    pub fn is_focused(&self, window: &Window) -> bool {
 306        window.focus == Some(*self)
 307    }
 308
 309    /// Obtains whether the element associated with this handle contains the focused
 310    /// element or is itself focused.
 311    pub fn contains_focused(&self, window: &Window, cx: &App) -> bool {
 312        window
 313            .focused(cx)
 314            .is_some_and(|focused| self.contains(focused.id, window))
 315    }
 316
 317    /// Obtains whether the element associated with this handle is contained within the
 318    /// focused element or is itself focused.
 319    pub fn within_focused(&self, window: &Window, cx: &App) -> bool {
 320        let focused = window.focused(cx);
 321        focused.is_some_and(|focused| focused.id.contains(*self, window))
 322    }
 323
 324    /// Obtains whether this handle contains the given handle in the most recently rendered frame.
 325    pub(crate) fn contains(&self, other: Self, window: &Window) -> bool {
 326        window
 327            .rendered_frame
 328            .dispatch_tree
 329            .focus_contains(*self, other)
 330    }
 331}
 332
 333/// A handle which can be used to track and manipulate the focused element in a window.
 334pub struct FocusHandle {
 335    pub(crate) id: FocusId,
 336    handles: Arc<FocusMap>,
 337    /// The index of this element in the tab order.
 338    pub tab_index: isize,
 339    /// Whether this element can be focused by tab navigation.
 340    pub tab_stop: bool,
 341}
 342
 343impl std::fmt::Debug for FocusHandle {
 344    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
 345        f.write_fmt(format_args!("FocusHandle({:?})", self.id))
 346    }
 347}
 348
 349impl FocusHandle {
 350    pub(crate) fn new(handles: &Arc<FocusMap>) -> Self {
 351        let id = handles.write().insert(FocusRef {
 352            ref_count: AtomicUsize::new(1),
 353            tab_index: 0,
 354            tab_stop: false,
 355        });
 356
 357        Self {
 358            id,
 359            tab_index: 0,
 360            tab_stop: false,
 361            handles: handles.clone(),
 362        }
 363    }
 364
 365    pub(crate) fn for_id(id: FocusId, handles: &Arc<FocusMap>) -> Option<Self> {
 366        let lock = handles.read();
 367        let focus = lock.get(id)?;
 368        if atomic_incr_if_not_zero(&focus.ref_count) == 0 {
 369            return None;
 370        }
 371        Some(Self {
 372            id,
 373            tab_index: focus.tab_index,
 374            tab_stop: focus.tab_stop,
 375            handles: handles.clone(),
 376        })
 377    }
 378
 379    /// Sets the tab index of the element associated with this handle.
 380    pub fn tab_index(mut self, index: isize) -> Self {
 381        self.tab_index = index;
 382        if let Some(focus) = self.handles.write().get_mut(self.id) {
 383            focus.tab_index = index;
 384        }
 385        self
 386    }
 387
 388    /// Sets whether the element associated with this handle is a tab stop.
 389    ///
 390    /// When `false`, the element will not be included in the tab order.
 391    pub fn tab_stop(mut self, tab_stop: bool) -> Self {
 392        self.tab_stop = tab_stop;
 393        if let Some(focus) = self.handles.write().get_mut(self.id) {
 394            focus.tab_stop = tab_stop;
 395        }
 396        self
 397    }
 398
 399    /// Converts this focus handle into a weak variant, which does not prevent it from being released.
 400    pub fn downgrade(&self) -> WeakFocusHandle {
 401        WeakFocusHandle {
 402            id: self.id,
 403            handles: Arc::downgrade(&self.handles),
 404        }
 405    }
 406
 407    /// Moves the focus to the element associated with this handle.
 408    pub fn focus(&self, window: &mut Window, cx: &mut App) {
 409        window.focus(self, cx)
 410    }
 411
 412    /// Obtains whether the element associated with this handle is currently focused.
 413    pub fn is_focused(&self, window: &Window) -> bool {
 414        self.id.is_focused(window)
 415    }
 416
 417    /// Obtains whether the element associated with this handle contains the focused
 418    /// element or is itself focused.
 419    pub fn contains_focused(&self, window: &Window, cx: &App) -> bool {
 420        self.id.contains_focused(window, cx)
 421    }
 422
 423    /// Obtains whether the element associated with this handle is contained within the
 424    /// focused element or is itself focused.
 425    pub fn within_focused(&self, window: &Window, cx: &mut App) -> bool {
 426        self.id.within_focused(window, cx)
 427    }
 428
 429    /// Obtains whether this handle contains the given handle in the most recently rendered frame.
 430    pub fn contains(&self, other: &Self, window: &Window) -> bool {
 431        self.id.contains(other.id, window)
 432    }
 433
 434    /// Dispatch an action on the element that rendered this focus handle
 435    pub fn dispatch_action(&self, action: &dyn Action, window: &mut Window, cx: &mut App) {
 436        if let Some(node_id) = window
 437            .rendered_frame
 438            .dispatch_tree
 439            .focusable_node_id(self.id)
 440        {
 441            window.dispatch_action_on_node(node_id, action, cx)
 442        }
 443    }
 444}
 445
 446impl Clone for FocusHandle {
 447    fn clone(&self) -> Self {
 448        Self::for_id(self.id, &self.handles).unwrap()
 449    }
 450}
 451
 452impl PartialEq for FocusHandle {
 453    fn eq(&self, other: &Self) -> bool {
 454        self.id == other.id
 455    }
 456}
 457
 458impl Eq for FocusHandle {}
 459
 460impl Drop for FocusHandle {
 461    fn drop(&mut self) {
 462        self.handles
 463            .read()
 464            .get(self.id)
 465            .unwrap()
 466            .ref_count
 467            .fetch_sub(1, SeqCst);
 468    }
 469}
 470
 471/// A weak reference to a focus handle.
 472#[derive(Clone, Debug)]
 473pub struct WeakFocusHandle {
 474    pub(crate) id: FocusId,
 475    pub(crate) handles: Weak<FocusMap>,
 476}
 477
 478impl WeakFocusHandle {
 479    /// Attempts to upgrade the [WeakFocusHandle] to a [FocusHandle].
 480    pub fn upgrade(&self) -> Option<FocusHandle> {
 481        let handles = self.handles.upgrade()?;
 482        FocusHandle::for_id(self.id, &handles)
 483    }
 484}
 485
 486impl PartialEq for WeakFocusHandle {
 487    fn eq(&self, other: &WeakFocusHandle) -> bool {
 488        self.id == other.id
 489    }
 490}
 491
 492impl Eq for WeakFocusHandle {}
 493
 494impl PartialEq<FocusHandle> for WeakFocusHandle {
 495    fn eq(&self, other: &FocusHandle) -> bool {
 496        self.id == other.id
 497    }
 498}
 499
 500impl PartialEq<WeakFocusHandle> for FocusHandle {
 501    fn eq(&self, other: &WeakFocusHandle) -> bool {
 502        self.id == other.id
 503    }
 504}
 505
 506/// Focusable allows users of your view to easily
 507/// focus it (using window.focus_view(cx, view))
 508pub trait Focusable: 'static {
 509    /// Returns the focus handle associated with this view.
 510    fn focus_handle(&self, cx: &App) -> FocusHandle;
 511}
 512
 513impl<V: Focusable> Focusable for Entity<V> {
 514    fn focus_handle(&self, cx: &App) -> FocusHandle {
 515        self.read(cx).focus_handle(cx)
 516    }
 517}
 518
 519/// ManagedView is a view (like a Modal, Popover, Menu, etc.)
 520/// where the lifecycle of the view is handled by another view.
 521pub trait ManagedView: Focusable + EventEmitter<DismissEvent> + Render {}
 522
 523impl<M: Focusable + EventEmitter<DismissEvent> + Render> ManagedView for M {}
 524
 525/// Emitted by implementers of [`ManagedView`] to indicate the view should be dismissed, such as when a view is presented as a modal.
 526pub struct DismissEvent;
 527
 528type FrameCallback = Box<dyn FnOnce(&mut Window, &mut App)>;
 529
 530pub(crate) type AnyMouseListener =
 531    Box<dyn FnMut(&dyn Any, DispatchPhase, &mut Window, &mut App) + 'static>;
 532
 533#[derive(Clone)]
 534pub(crate) struct CursorStyleRequest {
 535    pub(crate) hitbox_id: Option<HitboxId>,
 536    pub(crate) style: CursorStyle,
 537}
 538
 539#[derive(Default, Eq, PartialEq)]
 540pub(crate) struct HitTest {
 541    pub(crate) ids: SmallVec<[HitboxId; 8]>,
 542    pub(crate) hover_hitbox_count: usize,
 543}
 544
 545/// A type of window control area that corresponds to the platform window.
 546#[derive(Clone, Copy, Debug, Eq, PartialEq)]
 547pub enum WindowControlArea {
 548    /// An area that allows dragging of the platform window.
 549    Drag,
 550    /// An area that allows closing of the platform window.
 551    Close,
 552    /// An area that allows maximizing of the platform window.
 553    Max,
 554    /// An area that allows minimizing of the platform window.
 555    Min,
 556}
 557
 558/// An identifier for a [Hitbox] which also includes [HitboxBehavior].
 559#[derive(Copy, Clone, Debug, Eq, PartialEq, Hash)]
 560pub struct HitboxId(u64);
 561
 562impl HitboxId {
 563    /// Checks if the hitbox with this ID is currently hovered. Except when handling
 564    /// `ScrollWheelEvent`, this is typically what you want when determining whether to handle mouse
 565    /// events or paint hover styles.
 566    ///
 567    /// See [`Hitbox::is_hovered`] for details.
 568    pub fn is_hovered(self, window: &Window) -> bool {
 569        let hit_test = &window.mouse_hit_test;
 570        for id in hit_test.ids.iter().take(hit_test.hover_hitbox_count) {
 571            if self == *id {
 572                return true;
 573            }
 574        }
 575        false
 576    }
 577
 578    /// Checks if the hitbox with this ID contains the mouse and should handle scroll events.
 579    /// Typically this should only be used when handling `ScrollWheelEvent`, and otherwise
 580    /// `is_hovered` should be used. See the documentation of `Hitbox::is_hovered` for details about
 581    /// this distinction.
 582    pub fn should_handle_scroll(self, window: &Window) -> bool {
 583        window.mouse_hit_test.ids.contains(&self)
 584    }
 585
 586    fn next(mut self) -> HitboxId {
 587        HitboxId(self.0.wrapping_add(1))
 588    }
 589}
 590
 591/// A rectangular region that potentially blocks hitboxes inserted prior.
 592/// See [Window::insert_hitbox] for more details.
 593#[derive(Clone, Debug, Deref)]
 594pub struct Hitbox {
 595    /// A unique identifier for the hitbox.
 596    pub id: HitboxId,
 597    /// The bounds of the hitbox.
 598    #[deref]
 599    pub bounds: Bounds<Pixels>,
 600    /// The content mask when the hitbox was inserted.
 601    pub content_mask: ContentMask<Pixels>,
 602    /// Flags that specify hitbox behavior.
 603    pub behavior: HitboxBehavior,
 604}
 605
 606impl Hitbox {
 607    /// Checks if the hitbox is currently hovered. Except when handling `ScrollWheelEvent`, this is
 608    /// typically what you want when determining whether to handle mouse events or paint hover
 609    /// styles.
 610    ///
 611    /// This can return `false` even when the hitbox contains the mouse, if a hitbox in front of
 612    /// this sets `HitboxBehavior::BlockMouse` (`InteractiveElement::occlude`) or
 613    /// `HitboxBehavior::BlockMouseExceptScroll` (`InteractiveElement::block_mouse_except_scroll`).
 614    ///
 615    /// Handling of `ScrollWheelEvent` should typically use `should_handle_scroll` instead.
 616    /// Concretely, this is due to use-cases like overlays that cause the elements under to be
 617    /// non-interactive while still allowing scrolling. More abstractly, this is because
 618    /// `is_hovered` is about element interactions directly under the mouse - mouse moves, clicks,
 619    /// hover styling, etc. In contrast, scrolling is about finding the current outer scrollable
 620    /// container.
 621    pub fn is_hovered(&self, window: &Window) -> bool {
 622        self.id.is_hovered(window)
 623    }
 624
 625    /// Checks if the hitbox contains the mouse and should handle scroll events. Typically this
 626    /// should only be used when handling `ScrollWheelEvent`, and otherwise `is_hovered` should be
 627    /// used. See the documentation of `Hitbox::is_hovered` for details about this distinction.
 628    ///
 629    /// This can return `false` even when the hitbox contains the mouse, if a hitbox in front of
 630    /// this sets `HitboxBehavior::BlockMouse` (`InteractiveElement::occlude`).
 631    pub fn should_handle_scroll(&self, window: &Window) -> bool {
 632        self.id.should_handle_scroll(window)
 633    }
 634}
 635
 636/// How the hitbox affects mouse behavior.
 637#[derive(Copy, Clone, Debug, Default, PartialEq, Eq)]
 638pub enum HitboxBehavior {
 639    /// Normal hitbox mouse behavior, doesn't affect mouse handling for other hitboxes.
 640    #[default]
 641    Normal,
 642
 643    /// All hitboxes behind this hitbox will be ignored and so will have `hitbox.is_hovered() ==
 644    /// false` and `hitbox.should_handle_scroll() == false`. Typically for elements this causes
 645    /// skipping of all mouse events, hover styles, and tooltips. This flag is set by
 646    /// [`InteractiveElement::occlude`].
 647    ///
 648    /// For mouse handlers that check those hitboxes, this behaves the same as registering a
 649    /// bubble-phase handler for every mouse event type:
 650    ///
 651    /// ```ignore
 652    /// window.on_mouse_event(move |_: &EveryMouseEventTypeHere, phase, window, cx| {
 653    ///     if phase == DispatchPhase::Capture && hitbox.is_hovered(window) {
 654    ///         cx.stop_propagation();
 655    ///     }
 656    /// })
 657    /// ```
 658    ///
 659    /// This has effects beyond event handling - any use of hitbox checking, such as hover
 660    /// styles and tooltips. These other behaviors are the main point of this mechanism. An
 661    /// alternative might be to not affect mouse event handling - but this would allow
 662    /// inconsistent UI where clicks and moves interact with elements that are not considered to
 663    /// be hovered.
 664    BlockMouse,
 665
 666    /// All hitboxes behind this hitbox will have `hitbox.is_hovered() == false`, even when
 667    /// `hitbox.should_handle_scroll() == true`. Typically for elements this causes all mouse
 668    /// interaction except scroll events to be ignored - see the documentation of
 669    /// [`Hitbox::is_hovered`] for details. This flag is set by
 670    /// [`InteractiveElement::block_mouse_except_scroll`].
 671    ///
 672    /// For mouse handlers that check those hitboxes, this behaves the same as registering a
 673    /// bubble-phase handler for every mouse event type **except** `ScrollWheelEvent`:
 674    ///
 675    /// ```ignore
 676    /// window.on_mouse_event(move |_: &EveryMouseEventTypeExceptScroll, phase, window, cx| {
 677    ///     if phase == DispatchPhase::Bubble && hitbox.should_handle_scroll(window) {
 678    ///         cx.stop_propagation();
 679    ///     }
 680    /// })
 681    /// ```
 682    ///
 683    /// See the documentation of [`Hitbox::is_hovered`] for details of why `ScrollWheelEvent` is
 684    /// handled differently than other mouse events. If also blocking these scroll events is
 685    /// desired, then a `cx.stop_propagation()` handler like the one above can be used.
 686    ///
 687    /// This has effects beyond event handling - this affects any use of `is_hovered`, such as
 688    /// hover styles and tooltips. These other behaviors are the main point of this mechanism.
 689    /// An alternative might be to not affect mouse event handling - but this would allow
 690    /// inconsistent UI where clicks and moves interact with elements that are not considered to
 691    /// be hovered.
 692    BlockMouseExceptScroll,
 693}
 694
 695/// An identifier for a tooltip.
 696#[derive(Copy, Clone, Debug, Default, Eq, PartialEq)]
 697pub struct TooltipId(usize);
 698
 699impl TooltipId {
 700    /// Checks if the tooltip is currently hovered.
 701    pub fn is_hovered(&self, window: &Window) -> bool {
 702        window
 703            .tooltip_bounds
 704            .as_ref()
 705            .is_some_and(|tooltip_bounds| {
 706                tooltip_bounds.id == *self
 707                    && tooltip_bounds.bounds.contains(&window.mouse_position())
 708            })
 709    }
 710}
 711
 712pub(crate) struct TooltipBounds {
 713    id: TooltipId,
 714    bounds: Bounds<Pixels>,
 715}
 716
 717#[derive(Clone)]
 718pub(crate) struct TooltipRequest {
 719    id: TooltipId,
 720    tooltip: AnyTooltip,
 721}
 722
 723pub(crate) struct DeferredDraw {
 724    current_view: EntityId,
 725    priority: usize,
 726    parent_node: DispatchNodeId,
 727    element_id_stack: SmallVec<[ElementId; 32]>,
 728    text_style_stack: Vec<TextStyleRefinement>,
 729    rem_size: Pixels,
 730    element: Option<AnyElement>,
 731    absolute_offset: Point<Pixels>,
 732    prepaint_range: Range<PrepaintStateIndex>,
 733    paint_range: Range<PaintIndex>,
 734}
 735
 736pub(crate) struct Frame {
 737    pub(crate) focus: Option<FocusId>,
 738    pub(crate) window_active: bool,
 739    pub(crate) element_states: FxHashMap<(GlobalElementId, TypeId), ElementStateBox>,
 740    accessed_element_states: Vec<(GlobalElementId, TypeId)>,
 741    pub(crate) mouse_listeners: Vec<Option<AnyMouseListener>>,
 742    pub(crate) dispatch_tree: DispatchTree,
 743    pub(crate) scene: Scene,
 744    pub(crate) hitboxes: Vec<Hitbox>,
 745    pub(crate) window_control_hitboxes: Vec<(WindowControlArea, Hitbox)>,
 746    pub(crate) deferred_draws: Vec<DeferredDraw>,
 747    pub(crate) input_handlers: Vec<Option<PlatformInputHandler>>,
 748    pub(crate) tooltip_requests: Vec<Option<TooltipRequest>>,
 749    pub(crate) cursor_styles: Vec<CursorStyleRequest>,
 750    #[cfg(any(test, feature = "test-support"))]
 751    pub(crate) debug_bounds: FxHashMap<String, Bounds<Pixels>>,
 752    #[cfg(any(feature = "inspector", debug_assertions))]
 753    pub(crate) next_inspector_instance_ids: FxHashMap<Rc<crate::InspectorElementPath>, usize>,
 754    #[cfg(any(feature = "inspector", debug_assertions))]
 755    pub(crate) inspector_hitboxes: FxHashMap<HitboxId, crate::InspectorElementId>,
 756    pub(crate) tab_stops: TabStopMap,
 757}
 758
 759#[derive(Clone, Default)]
 760pub(crate) struct PrepaintStateIndex {
 761    hitboxes_index: usize,
 762    tooltips_index: usize,
 763    deferred_draws_index: usize,
 764    dispatch_tree_index: usize,
 765    accessed_element_states_index: usize,
 766    line_layout_index: LineLayoutIndex,
 767}
 768
 769#[derive(Clone, Default)]
 770pub(crate) struct PaintIndex {
 771    scene_index: usize,
 772    mouse_listeners_index: usize,
 773    input_handlers_index: usize,
 774    cursor_styles_index: usize,
 775    accessed_element_states_index: usize,
 776    tab_handle_index: usize,
 777    line_layout_index: LineLayoutIndex,
 778}
 779
 780impl Frame {
 781    pub(crate) fn new(dispatch_tree: DispatchTree) -> Self {
 782        Frame {
 783            focus: None,
 784            window_active: false,
 785            element_states: FxHashMap::default(),
 786            accessed_element_states: Vec::new(),
 787            mouse_listeners: Vec::new(),
 788            dispatch_tree,
 789            scene: Scene::default(),
 790            hitboxes: Vec::new(),
 791            window_control_hitboxes: Vec::new(),
 792            deferred_draws: Vec::new(),
 793            input_handlers: Vec::new(),
 794            tooltip_requests: Vec::new(),
 795            cursor_styles: Vec::new(),
 796
 797            #[cfg(any(test, feature = "test-support"))]
 798            debug_bounds: FxHashMap::default(),
 799
 800            #[cfg(any(feature = "inspector", debug_assertions))]
 801            next_inspector_instance_ids: FxHashMap::default(),
 802
 803            #[cfg(any(feature = "inspector", debug_assertions))]
 804            inspector_hitboxes: FxHashMap::default(),
 805            tab_stops: TabStopMap::default(),
 806        }
 807    }
 808
 809    pub(crate) fn clear(&mut self) {
 810        self.element_states.clear();
 811        self.accessed_element_states.clear();
 812        self.mouse_listeners.clear();
 813        self.dispatch_tree.clear();
 814        self.scene.clear();
 815        self.input_handlers.clear();
 816        self.tooltip_requests.clear();
 817        self.cursor_styles.clear();
 818        self.hitboxes.clear();
 819        self.window_control_hitboxes.clear();
 820        self.deferred_draws.clear();
 821        self.tab_stops.clear();
 822        self.focus = None;
 823
 824        #[cfg(any(feature = "inspector", debug_assertions))]
 825        {
 826            self.next_inspector_instance_ids.clear();
 827            self.inspector_hitboxes.clear();
 828        }
 829    }
 830
 831    pub(crate) fn cursor_style(&self, window: &Window) -> Option<CursorStyle> {
 832        self.cursor_styles
 833            .iter()
 834            .rev()
 835            .fold_while(None, |style, request| match request.hitbox_id {
 836                None => Done(Some(request.style)),
 837                Some(hitbox_id) => Continue(
 838                    style.or_else(|| hitbox_id.is_hovered(window).then_some(request.style)),
 839                ),
 840            })
 841            .into_inner()
 842    }
 843
 844    pub(crate) fn hit_test(&self, position: Point<Pixels>) -> HitTest {
 845        let mut set_hover_hitbox_count = false;
 846        let mut hit_test = HitTest::default();
 847        for hitbox in self.hitboxes.iter().rev() {
 848            let bounds = hitbox.bounds.intersect(&hitbox.content_mask.bounds);
 849            if bounds.contains(&position) {
 850                hit_test.ids.push(hitbox.id);
 851                if !set_hover_hitbox_count
 852                    && hitbox.behavior == HitboxBehavior::BlockMouseExceptScroll
 853                {
 854                    hit_test.hover_hitbox_count = hit_test.ids.len();
 855                    set_hover_hitbox_count = true;
 856                }
 857                if hitbox.behavior == HitboxBehavior::BlockMouse {
 858                    break;
 859                }
 860            }
 861        }
 862        if !set_hover_hitbox_count {
 863            hit_test.hover_hitbox_count = hit_test.ids.len();
 864        }
 865        hit_test
 866    }
 867
 868    pub(crate) fn focus_path(&self) -> SmallVec<[FocusId; 8]> {
 869        self.focus
 870            .map(|focus_id| self.dispatch_tree.focus_path(focus_id))
 871            .unwrap_or_default()
 872    }
 873
 874    pub(crate) fn finish(&mut self, prev_frame: &mut Self) {
 875        for element_state_key in &self.accessed_element_states {
 876            if let Some((element_state_key, element_state)) =
 877                prev_frame.element_states.remove_entry(element_state_key)
 878            {
 879                self.element_states.insert(element_state_key, element_state);
 880            }
 881        }
 882
 883        self.scene.finish();
 884    }
 885}
 886
 887#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Ord, PartialOrd)]
 888enum InputModality {
 889    Mouse,
 890    Keyboard,
 891}
 892
 893/// Holds the state for a specific window.
 894pub struct Window {
 895    pub(crate) handle: AnyWindowHandle,
 896    pub(crate) invalidator: WindowInvalidator,
 897    pub(crate) removed: bool,
 898    pub(crate) platform_window: Box<dyn PlatformWindow>,
 899    display_id: Option<DisplayId>,
 900    sprite_atlas: Arc<dyn PlatformAtlas>,
 901    text_system: Arc<WindowTextSystem>,
 902    text_rendering_mode: Rc<Cell<TextRenderingMode>>,
 903    rem_size: Pixels,
 904    /// The stack of override values for the window's rem size.
 905    ///
 906    /// This is used by `with_rem_size` to allow rendering an element tree with
 907    /// a given rem size.
 908    rem_size_override_stack: SmallVec<[Pixels; 8]>,
 909    pub(crate) viewport_size: Size<Pixels>,
 910    layout_engine: Option<TaffyLayoutEngine>,
 911    pub(crate) root: Option<AnyView>,
 912    pub(crate) element_id_stack: SmallVec<[ElementId; 32]>,
 913    pub(crate) text_style_stack: Vec<TextStyleRefinement>,
 914    pub(crate) rendered_entity_stack: Vec<EntityId>,
 915    pub(crate) element_offset_stack: Vec<Point<Pixels>>,
 916    pub(crate) element_opacity: f32,
 917    pub(crate) content_mask_stack: Vec<ContentMask<Pixels>>,
 918    pub(crate) requested_autoscroll: Option<Bounds<Pixels>>,
 919    pub(crate) image_cache_stack: Vec<AnyImageCache>,
 920    pub(crate) rendered_frame: Frame,
 921    pub(crate) next_frame: Frame,
 922    next_hitbox_id: HitboxId,
 923    pub(crate) next_tooltip_id: TooltipId,
 924    pub(crate) tooltip_bounds: Option<TooltipBounds>,
 925    next_frame_callbacks: Rc<RefCell<Vec<FrameCallback>>>,
 926    pub(crate) dirty_views: FxHashSet<EntityId>,
 927    focus_listeners: SubscriberSet<(), AnyWindowFocusListener>,
 928    pub(crate) focus_lost_listeners: SubscriberSet<(), AnyObserver>,
 929    default_prevented: bool,
 930    mouse_position: Point<Pixels>,
 931    mouse_hit_test: HitTest,
 932    modifiers: Modifiers,
 933    capslock: Capslock,
 934    scale_factor: f32,
 935    pub(crate) bounds_observers: SubscriberSet<(), AnyObserver>,
 936    appearance: WindowAppearance,
 937    pub(crate) appearance_observers: SubscriberSet<(), AnyObserver>,
 938    active: Rc<Cell<bool>>,
 939    hovered: Rc<Cell<bool>>,
 940    pub(crate) needs_present: Rc<Cell<bool>>,
 941    /// Tracks recent input event timestamps to determine if input is arriving at a high rate.
 942    /// Used to selectively enable VRR optimization only when input rate exceeds 60fps.
 943    pub(crate) input_rate_tracker: Rc<RefCell<InputRateTracker>>,
 944    last_input_modality: InputModality,
 945    pub(crate) refreshing: bool,
 946    pub(crate) activation_observers: SubscriberSet<(), AnyObserver>,
 947    pub(crate) focus: Option<FocusId>,
 948    focus_enabled: bool,
 949    pending_input: Option<PendingInput>,
 950    pending_modifier: ModifierState,
 951    pub(crate) pending_input_observers: SubscriberSet<(), AnyObserver>,
 952    prompt: Option<RenderablePromptHandle>,
 953    pub(crate) client_inset: Option<Pixels>,
 954    #[cfg(any(feature = "inspector", debug_assertions))]
 955    inspector: Option<Entity<Inspector>>,
 956}
 957
 958#[derive(Clone, Debug, Default)]
 959struct ModifierState {
 960    modifiers: Modifiers,
 961    saw_keystroke: bool,
 962}
 963
 964/// Tracks input event timestamps to determine if input is arriving at a high rate.
 965/// Used for selective VRR (Variable Refresh Rate) optimization.
 966#[derive(Clone, Debug)]
 967pub(crate) struct InputRateTracker {
 968    timestamps: Vec<Instant>,
 969    window: Duration,
 970    inputs_per_second: u32,
 971    sustain_until: Instant,
 972    sustain_duration: Duration,
 973}
 974
 975impl Default for InputRateTracker {
 976    fn default() -> Self {
 977        Self {
 978            timestamps: Vec::new(),
 979            window: Duration::from_millis(100),
 980            inputs_per_second: 60,
 981            sustain_until: Instant::now(),
 982            sustain_duration: Duration::from_secs(1),
 983        }
 984    }
 985}
 986
 987impl InputRateTracker {
 988    pub fn record_input(&mut self) {
 989        let now = Instant::now();
 990        self.timestamps.push(now);
 991        self.prune_old_timestamps(now);
 992
 993        let min_events = self.inputs_per_second as u128 * self.window.as_millis() / 1000;
 994        if self.timestamps.len() as u128 >= min_events {
 995            self.sustain_until = now + self.sustain_duration;
 996        }
 997    }
 998
 999    pub fn is_high_rate(&self) -> bool {
1000        Instant::now() < self.sustain_until
1001    }
1002
1003    fn prune_old_timestamps(&mut self, now: Instant) {
1004        self.timestamps
1005            .retain(|&t| now.duration_since(t) <= self.window);
1006    }
1007}
1008
1009#[derive(Clone, Copy, Debug, Eq, PartialEq)]
1010pub(crate) enum DrawPhase {
1011    None,
1012    Prepaint,
1013    Paint,
1014    Focus,
1015}
1016
1017#[derive(Default, Debug)]
1018struct PendingInput {
1019    keystrokes: SmallVec<[Keystroke; 1]>,
1020    focus: Option<FocusId>,
1021    timer: Option<Task<()>>,
1022    needs_timeout: bool,
1023}
1024
1025pub(crate) struct ElementStateBox {
1026    pub(crate) inner: Box<dyn Any>,
1027    #[cfg(debug_assertions)]
1028    pub(crate) type_name: &'static str,
1029}
1030
1031fn default_bounds(display_id: Option<DisplayId>, cx: &mut App) -> WindowBounds {
1032    // TODO, BUG: if you open a window with the currently active window
1033    // on the stack, this will erroneously fallback to `None`
1034    //
1035    // TODO these should be the initial window bounds not considering maximized/fullscreen
1036    let active_window_bounds = cx
1037        .active_window()
1038        .and_then(|w| w.update(cx, |_, window, _| window.window_bounds()).ok());
1039
1040    const CASCADE_OFFSET: f32 = 25.0;
1041
1042    let display = display_id
1043        .map(|id| cx.find_display(id))
1044        .unwrap_or_else(|| cx.primary_display());
1045
1046    let default_placement = || Bounds::new(point(px(0.), px(0.)), DEFAULT_WINDOW_SIZE);
1047
1048    // Use visible_bounds to exclude taskbar/dock areas
1049    let display_bounds = display
1050        .as_ref()
1051        .map(|d| d.visible_bounds())
1052        .unwrap_or_else(default_placement);
1053
1054    let (
1055        Bounds {
1056            origin: base_origin,
1057            size: base_size,
1058        },
1059        window_bounds_ctor,
1060    ): (_, fn(Bounds<Pixels>) -> WindowBounds) = match active_window_bounds {
1061        Some(bounds) => match bounds {
1062            WindowBounds::Windowed(bounds) => (bounds, WindowBounds::Windowed),
1063            WindowBounds::Maximized(bounds) => (bounds, WindowBounds::Maximized),
1064            WindowBounds::Fullscreen(bounds) => (bounds, WindowBounds::Fullscreen),
1065        },
1066        None => (
1067            display
1068                .as_ref()
1069                .map(|d| d.default_bounds())
1070                .unwrap_or_else(default_placement),
1071            WindowBounds::Windowed,
1072        ),
1073    };
1074
1075    let cascade_offset = point(px(CASCADE_OFFSET), px(CASCADE_OFFSET));
1076    let proposed_origin = base_origin + cascade_offset;
1077    let proposed_bounds = Bounds::new(proposed_origin, base_size);
1078
1079    let display_right = display_bounds.origin.x + display_bounds.size.width;
1080    let display_bottom = display_bounds.origin.y + display_bounds.size.height;
1081    let window_right = proposed_bounds.origin.x + proposed_bounds.size.width;
1082    let window_bottom = proposed_bounds.origin.y + proposed_bounds.size.height;
1083
1084    let fits_horizontally = window_right <= display_right;
1085    let fits_vertically = window_bottom <= display_bottom;
1086
1087    let final_origin = match (fits_horizontally, fits_vertically) {
1088        (true, true) => proposed_origin,
1089        (false, true) => point(display_bounds.origin.x, base_origin.y),
1090        (true, false) => point(base_origin.x, display_bounds.origin.y),
1091        (false, false) => display_bounds.origin,
1092    };
1093    window_bounds_ctor(Bounds::new(final_origin, base_size))
1094}
1095
1096impl Window {
1097    pub(crate) fn new(
1098        handle: AnyWindowHandle,
1099        options: WindowOptions,
1100        cx: &mut App,
1101    ) -> Result<Self> {
1102        let WindowOptions {
1103            window_bounds,
1104            titlebar,
1105            focus,
1106            show,
1107            kind,
1108            is_movable,
1109            is_resizable,
1110            is_minimizable,
1111            display_id,
1112            window_background,
1113            app_id,
1114            window_min_size,
1115            window_decorations,
1116            #[cfg_attr(not(target_os = "macos"), allow(unused_variables))]
1117            tabbing_identifier,
1118        } = options;
1119
1120        let window_bounds = window_bounds.unwrap_or_else(|| default_bounds(display_id, cx));
1121        let mut platform_window = cx.platform.open_window(
1122            handle,
1123            WindowParams {
1124                bounds: window_bounds.get_bounds(),
1125                titlebar,
1126                kind,
1127                is_movable,
1128                is_resizable,
1129                is_minimizable,
1130                focus,
1131                show,
1132                display_id,
1133                window_min_size,
1134                #[cfg(target_os = "macos")]
1135                tabbing_identifier,
1136            },
1137        )?;
1138
1139        let tab_bar_visible = platform_window.tab_bar_visible();
1140        SystemWindowTabController::init_visible(cx, tab_bar_visible);
1141        if let Some(tabs) = platform_window.tabbed_windows() {
1142            SystemWindowTabController::add_tab(cx, handle.window_id(), tabs);
1143        }
1144
1145        let display_id = platform_window.display().map(|display| display.id());
1146        let sprite_atlas = platform_window.sprite_atlas();
1147        let mouse_position = platform_window.mouse_position();
1148        let modifiers = platform_window.modifiers();
1149        let capslock = platform_window.capslock();
1150        let content_size = platform_window.content_size();
1151        let scale_factor = platform_window.scale_factor();
1152        let appearance = platform_window.appearance();
1153        let text_system = Arc::new(WindowTextSystem::new(cx.text_system().clone()));
1154        let invalidator = WindowInvalidator::new();
1155        let active = Rc::new(Cell::new(platform_window.is_active()));
1156        let hovered = Rc::new(Cell::new(platform_window.is_hovered()));
1157        let needs_present = Rc::new(Cell::new(false));
1158        let next_frame_callbacks: Rc<RefCell<Vec<FrameCallback>>> = Default::default();
1159        let input_rate_tracker = Rc::new(RefCell::new(InputRateTracker::default()));
1160        let last_frame_time = Rc::new(Cell::new(None));
1161
1162        platform_window
1163            .request_decorations(window_decorations.unwrap_or(WindowDecorations::Server));
1164        platform_window.set_background_appearance(window_background);
1165
1166        match window_bounds {
1167            WindowBounds::Fullscreen(_) => platform_window.toggle_fullscreen(),
1168            WindowBounds::Maximized(_) => platform_window.zoom(),
1169            WindowBounds::Windowed(_) => {}
1170        }
1171
1172        platform_window.on_close(Box::new({
1173            let window_id = handle.window_id();
1174            let mut cx = cx.to_async();
1175            move || {
1176                let _ = handle.update(&mut cx, |_, window, _| window.remove_window());
1177                let _ = cx.update(|cx| {
1178                    SystemWindowTabController::remove_tab(cx, window_id);
1179                });
1180            }
1181        }));
1182        platform_window.on_request_frame(Box::new({
1183            let mut cx = cx.to_async();
1184            let invalidator = invalidator.clone();
1185            let active = active.clone();
1186            let needs_present = needs_present.clone();
1187            let next_frame_callbacks = next_frame_callbacks.clone();
1188            let input_rate_tracker = input_rate_tracker.clone();
1189            move |request_frame_options| {
1190                let thermal_state = handle
1191                    .update(&mut cx, |_, _, cx| cx.thermal_state())
1192                    .log_err();
1193
1194                if thermal_state == Some(ThermalState::Serious)
1195                    || thermal_state == Some(ThermalState::Critical)
1196                {
1197                    let now = Instant::now();
1198                    let last_frame_time = last_frame_time.replace(Some(now));
1199
1200                    if let Some(last_frame) = last_frame_time
1201                        && now.duration_since(last_frame) < Duration::from_micros(16667)
1202                    {
1203                        return;
1204                    }
1205                }
1206
1207                let next_frame_callbacks = next_frame_callbacks.take();
1208                if !next_frame_callbacks.is_empty() {
1209                    handle
1210                        .update(&mut cx, |_, window, cx| {
1211                            for callback in next_frame_callbacks {
1212                                callback(window, cx);
1213                            }
1214                        })
1215                        .log_err();
1216                }
1217
1218                // Keep presenting if input was recently arriving at a high rate (>= 60fps).
1219                // Once high-rate input is detected, we sustain presentation for 1 second
1220                // to prevent display underclocking during active input.
1221                let needs_present = request_frame_options.require_presentation
1222                    || needs_present.get()
1223                    || (active.get() && input_rate_tracker.borrow_mut().is_high_rate());
1224
1225                if invalidator.is_dirty() || request_frame_options.force_render {
1226                    measure("frame duration", || {
1227                        handle
1228                            .update(&mut cx, |_, window, cx| {
1229                                let arena_clear_needed = window.draw(cx);
1230                                window.present();
1231                                arena_clear_needed.clear();
1232                            })
1233                            .log_err();
1234                    })
1235                } else if needs_present {
1236                    handle
1237                        .update(&mut cx, |_, window, _| window.present())
1238                        .log_err();
1239                }
1240
1241                handle
1242                    .update(&mut cx, |_, window, _| {
1243                        window.complete_frame();
1244                    })
1245                    .log_err();
1246            }
1247        }));
1248        platform_window.on_resize(Box::new({
1249            let mut cx = cx.to_async();
1250            move |_, _| {
1251                handle
1252                    .update(&mut cx, |_, window, cx| window.bounds_changed(cx))
1253                    .log_err();
1254            }
1255        }));
1256        platform_window.on_moved(Box::new({
1257            let mut cx = cx.to_async();
1258            move || {
1259                handle
1260                    .update(&mut cx, |_, window, cx| window.bounds_changed(cx))
1261                    .log_err();
1262            }
1263        }));
1264        platform_window.on_appearance_changed(Box::new({
1265            let mut cx = cx.to_async();
1266            move || {
1267                handle
1268                    .update(&mut cx, |_, window, cx| window.appearance_changed(cx))
1269                    .log_err();
1270            }
1271        }));
1272        platform_window.on_active_status_change(Box::new({
1273            let mut cx = cx.to_async();
1274            move |active| {
1275                handle
1276                    .update(&mut cx, |_, window, cx| {
1277                        window.active.set(active);
1278                        window.modifiers = window.platform_window.modifiers();
1279                        window.capslock = window.platform_window.capslock();
1280                        window
1281                            .activation_observers
1282                            .clone()
1283                            .retain(&(), |callback| callback(window, cx));
1284
1285                        window.bounds_changed(cx);
1286                        window.refresh();
1287
1288                        SystemWindowTabController::update_last_active(cx, window.handle.id);
1289                    })
1290                    .log_err();
1291            }
1292        }));
1293        platform_window.on_hover_status_change(Box::new({
1294            let mut cx = cx.to_async();
1295            move |active| {
1296                handle
1297                    .update(&mut cx, |_, window, _| {
1298                        window.hovered.set(active);
1299                        window.refresh();
1300                    })
1301                    .log_err();
1302            }
1303        }));
1304        platform_window.on_input({
1305            let mut cx = cx.to_async();
1306            Box::new(move |event| {
1307                handle
1308                    .update(&mut cx, |_, window, cx| window.dispatch_event(event, cx))
1309                    .log_err()
1310                    .unwrap_or(DispatchEventResult::default())
1311            })
1312        });
1313        platform_window.on_hit_test_window_control({
1314            let mut cx = cx.to_async();
1315            Box::new(move || {
1316                handle
1317                    .update(&mut cx, |_, window, _cx| {
1318                        for (area, hitbox) in &window.rendered_frame.window_control_hitboxes {
1319                            if window.mouse_hit_test.ids.contains(&hitbox.id) {
1320                                return Some(*area);
1321                            }
1322                        }
1323                        None
1324                    })
1325                    .log_err()
1326                    .unwrap_or(None)
1327            })
1328        });
1329        platform_window.on_move_tab_to_new_window({
1330            let mut cx = cx.to_async();
1331            Box::new(move || {
1332                handle
1333                    .update(&mut cx, |_, _window, cx| {
1334                        SystemWindowTabController::move_tab_to_new_window(cx, handle.window_id());
1335                    })
1336                    .log_err();
1337            })
1338        });
1339        platform_window.on_merge_all_windows({
1340            let mut cx = cx.to_async();
1341            Box::new(move || {
1342                handle
1343                    .update(&mut cx, |_, _window, cx| {
1344                        SystemWindowTabController::merge_all_windows(cx, handle.window_id());
1345                    })
1346                    .log_err();
1347            })
1348        });
1349        platform_window.on_select_next_tab({
1350            let mut cx = cx.to_async();
1351            Box::new(move || {
1352                handle
1353                    .update(&mut cx, |_, _window, cx| {
1354                        SystemWindowTabController::select_next_tab(cx, handle.window_id());
1355                    })
1356                    .log_err();
1357            })
1358        });
1359        platform_window.on_select_previous_tab({
1360            let mut cx = cx.to_async();
1361            Box::new(move || {
1362                handle
1363                    .update(&mut cx, |_, _window, cx| {
1364                        SystemWindowTabController::select_previous_tab(cx, handle.window_id())
1365                    })
1366                    .log_err();
1367            })
1368        });
1369        platform_window.on_toggle_tab_bar({
1370            let mut cx = cx.to_async();
1371            Box::new(move || {
1372                handle
1373                    .update(&mut cx, |_, window, cx| {
1374                        let tab_bar_visible = window.platform_window.tab_bar_visible();
1375                        SystemWindowTabController::set_visible(cx, tab_bar_visible);
1376                    })
1377                    .log_err();
1378            })
1379        });
1380
1381        if let Some(app_id) = app_id {
1382            platform_window.set_app_id(&app_id);
1383        }
1384
1385        platform_window.map_window().unwrap();
1386
1387        Ok(Window {
1388            handle,
1389            invalidator,
1390            removed: false,
1391            platform_window,
1392            display_id,
1393            sprite_atlas,
1394            text_system,
1395            text_rendering_mode: cx.text_rendering_mode.clone(),
1396            rem_size: px(16.),
1397            rem_size_override_stack: SmallVec::new(),
1398            viewport_size: content_size,
1399            layout_engine: Some(TaffyLayoutEngine::new()),
1400            root: None,
1401            element_id_stack: SmallVec::default(),
1402            text_style_stack: Vec::new(),
1403            rendered_entity_stack: Vec::new(),
1404            element_offset_stack: Vec::new(),
1405            content_mask_stack: Vec::new(),
1406            element_opacity: 1.0,
1407            requested_autoscroll: None,
1408            rendered_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
1409            next_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
1410            next_frame_callbacks,
1411            next_hitbox_id: HitboxId(0),
1412            next_tooltip_id: TooltipId::default(),
1413            tooltip_bounds: None,
1414            dirty_views: FxHashSet::default(),
1415            focus_listeners: SubscriberSet::new(),
1416            focus_lost_listeners: SubscriberSet::new(),
1417            default_prevented: true,
1418            mouse_position,
1419            mouse_hit_test: HitTest::default(),
1420            modifiers,
1421            capslock,
1422            scale_factor,
1423            bounds_observers: SubscriberSet::new(),
1424            appearance,
1425            appearance_observers: SubscriberSet::new(),
1426            active,
1427            hovered,
1428            needs_present,
1429            input_rate_tracker,
1430            last_input_modality: InputModality::Mouse,
1431            refreshing: false,
1432            activation_observers: SubscriberSet::new(),
1433            focus: None,
1434            focus_enabled: true,
1435            pending_input: None,
1436            pending_modifier: ModifierState::default(),
1437            pending_input_observers: SubscriberSet::new(),
1438            prompt: None,
1439            client_inset: None,
1440            image_cache_stack: Vec::new(),
1441            #[cfg(any(feature = "inspector", debug_assertions))]
1442            inspector: None,
1443        })
1444    }
1445
1446    pub(crate) fn new_focus_listener(
1447        &self,
1448        value: AnyWindowFocusListener,
1449    ) -> (Subscription, impl FnOnce() + use<>) {
1450        self.focus_listeners.insert((), value)
1451    }
1452}
1453
1454#[derive(Clone, Debug, Default, PartialEq, Eq)]
1455#[expect(missing_docs)]
1456pub struct DispatchEventResult {
1457    pub propagate: bool,
1458    pub default_prevented: bool,
1459}
1460
1461/// Indicates which region of the window is visible. Content falling outside of this mask will not be
1462/// rendered. Currently, only rectangular content masks are supported, but we give the mask its own type
1463/// to leave room to support more complex shapes in the future.
1464#[derive(Clone, Debug, Default, PartialEq, Eq)]
1465#[repr(C)]
1466pub struct ContentMask<P: Clone + Debug + Default + PartialEq> {
1467    /// The bounds
1468    pub bounds: Bounds<P>,
1469}
1470
1471impl ContentMask<Pixels> {
1472    /// Scale the content mask's pixel units by the given scaling factor.
1473    pub fn scale(&self, factor: f32) -> ContentMask<ScaledPixels> {
1474        ContentMask {
1475            bounds: self.bounds.scale(factor),
1476        }
1477    }
1478
1479    /// Intersect the content mask with the given content mask.
1480    pub fn intersect(&self, other: &Self) -> Self {
1481        let bounds = self.bounds.intersect(&other.bounds);
1482        ContentMask { bounds }
1483    }
1484}
1485
1486impl Window {
1487    fn mark_view_dirty(&mut self, view_id: EntityId) {
1488        // Mark ancestor views as dirty. If already in the `dirty_views` set, then all its ancestors
1489        // should already be dirty.
1490        for view_id in self
1491            .rendered_frame
1492            .dispatch_tree
1493            .view_path_reversed(view_id)
1494        {
1495            if !self.dirty_views.insert(view_id) {
1496                break;
1497            }
1498        }
1499    }
1500
1501    /// Registers a callback to be invoked when the window appearance changes.
1502    pub fn observe_window_appearance(
1503        &self,
1504        mut callback: impl FnMut(&mut Window, &mut App) + 'static,
1505    ) -> Subscription {
1506        let (subscription, activate) = self.appearance_observers.insert(
1507            (),
1508            Box::new(move |window, cx| {
1509                callback(window, cx);
1510                true
1511            }),
1512        );
1513        activate();
1514        subscription
1515    }
1516
1517    /// Replaces the root entity of the window with a new one.
1518    pub fn replace_root<E>(
1519        &mut self,
1520        cx: &mut App,
1521        build_view: impl FnOnce(&mut Window, &mut Context<E>) -> E,
1522    ) -> Entity<E>
1523    where
1524        E: 'static + Render,
1525    {
1526        let view = cx.new(|cx| build_view(self, cx));
1527        self.root = Some(view.clone().into());
1528        self.refresh();
1529        view
1530    }
1531
1532    /// Returns the root entity of the window, if it has one.
1533    pub fn root<E>(&self) -> Option<Option<Entity<E>>>
1534    where
1535        E: 'static + Render,
1536    {
1537        self.root
1538            .as_ref()
1539            .map(|view| view.clone().downcast::<E>().ok())
1540    }
1541
1542    /// Obtain a handle to the window that belongs to this context.
1543    pub fn window_handle(&self) -> AnyWindowHandle {
1544        self.handle
1545    }
1546
1547    /// Mark the window as dirty, scheduling it to be redrawn on the next frame.
1548    pub fn refresh(&mut self) {
1549        if self.invalidator.not_drawing() {
1550            self.refreshing = true;
1551            self.invalidator.set_dirty(true);
1552        }
1553    }
1554
1555    /// Close this window.
1556    pub fn remove_window(&mut self) {
1557        self.removed = true;
1558    }
1559
1560    /// Obtain the currently focused [`FocusHandle`]. If no elements are focused, returns `None`.
1561    pub fn focused(&self, cx: &App) -> Option<FocusHandle> {
1562        self.focus
1563            .and_then(|id| FocusHandle::for_id(id, &cx.focus_handles))
1564    }
1565
1566    /// Move focus to the element associated with the given [`FocusHandle`].
1567    pub fn focus(&mut self, handle: &FocusHandle, cx: &mut App) {
1568        if !self.focus_enabled || self.focus == Some(handle.id) {
1569            return;
1570        }
1571
1572        self.focus = Some(handle.id);
1573        self.clear_pending_keystrokes();
1574
1575        // Avoid re-entrant entity updates by deferring observer notifications to the end of the
1576        // current effect cycle, and only for this window.
1577        let window_handle = self.handle;
1578        cx.defer(move |cx| {
1579            window_handle
1580                .update(cx, |_, window, cx| {
1581                    window.pending_input_changed(cx);
1582                })
1583                .ok();
1584        });
1585
1586        self.refresh();
1587    }
1588
1589    /// Remove focus from all elements within this context's window.
1590    pub fn blur(&mut self) {
1591        if !self.focus_enabled {
1592            return;
1593        }
1594
1595        self.focus = None;
1596        self.refresh();
1597    }
1598
1599    /// Blur the window and don't allow anything in it to be focused again.
1600    pub fn disable_focus(&mut self) {
1601        self.blur();
1602        self.focus_enabled = false;
1603    }
1604
1605    /// Move focus to next tab stop.
1606    pub fn focus_next(&mut self, cx: &mut App) {
1607        if !self.focus_enabled {
1608            return;
1609        }
1610
1611        if let Some(handle) = self.rendered_frame.tab_stops.next(self.focus.as_ref()) {
1612            self.focus(&handle, cx)
1613        }
1614    }
1615
1616    /// Move focus to previous tab stop.
1617    pub fn focus_prev(&mut self, cx: &mut App) {
1618        if !self.focus_enabled {
1619            return;
1620        }
1621
1622        if let Some(handle) = self.rendered_frame.tab_stops.prev(self.focus.as_ref()) {
1623            self.focus(&handle, cx)
1624        }
1625    }
1626
1627    /// Accessor for the text system.
1628    pub fn text_system(&self) -> &Arc<WindowTextSystem> {
1629        &self.text_system
1630    }
1631
1632    /// The current text style. Which is composed of all the style refinements provided to `with_text_style`.
1633    pub fn text_style(&self) -> TextStyle {
1634        let mut style = TextStyle::default();
1635        for refinement in &self.text_style_stack {
1636            style.refine(refinement);
1637        }
1638        style
1639    }
1640
1641    /// Check if the platform window is maximized.
1642    ///
1643    /// On some platforms (namely Windows) this is different than the bounds being the size of the display
1644    pub fn is_maximized(&self) -> bool {
1645        self.platform_window.is_maximized()
1646    }
1647
1648    /// request a certain window decoration (Wayland)
1649    pub fn request_decorations(&self, decorations: WindowDecorations) {
1650        self.platform_window.request_decorations(decorations);
1651    }
1652
1653    /// Start a window resize operation (Wayland)
1654    pub fn start_window_resize(&self, edge: ResizeEdge) {
1655        self.platform_window.start_window_resize(edge);
1656    }
1657
1658    /// Return the `WindowBounds` to indicate that how a window should be opened
1659    /// after it has been closed
1660    pub fn window_bounds(&self) -> WindowBounds {
1661        self.platform_window.window_bounds()
1662    }
1663
1664    /// Return the `WindowBounds` excluding insets (Wayland and X11)
1665    pub fn inner_window_bounds(&self) -> WindowBounds {
1666        self.platform_window.inner_window_bounds()
1667    }
1668
1669    /// Dispatch the given action on the currently focused element.
1670    pub fn dispatch_action(&mut self, action: Box<dyn Action>, cx: &mut App) {
1671        let focus_id = self.focused(cx).map(|handle| handle.id);
1672
1673        let window = self.handle;
1674        cx.defer(move |cx| {
1675            window
1676                .update(cx, |_, window, cx| {
1677                    let node_id = window.focus_node_id_in_rendered_frame(focus_id);
1678                    window.dispatch_action_on_node(node_id, action.as_ref(), cx);
1679                })
1680                .log_err();
1681        })
1682    }
1683
1684    pub(crate) fn dispatch_keystroke_observers(
1685        &mut self,
1686        event: &dyn Any,
1687        action: Option<Box<dyn Action>>,
1688        context_stack: Vec<KeyContext>,
1689        cx: &mut App,
1690    ) {
1691        let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() else {
1692            return;
1693        };
1694
1695        cx.keystroke_observers.clone().retain(&(), move |callback| {
1696            (callback)(
1697                &KeystrokeEvent {
1698                    keystroke: key_down_event.keystroke.clone(),
1699                    action: action.as_ref().map(|action| action.boxed_clone()),
1700                    context_stack: context_stack.clone(),
1701                },
1702                self,
1703                cx,
1704            )
1705        });
1706    }
1707
1708    pub(crate) fn dispatch_keystroke_interceptors(
1709        &mut self,
1710        event: &dyn Any,
1711        context_stack: Vec<KeyContext>,
1712        cx: &mut App,
1713    ) {
1714        let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() else {
1715            return;
1716        };
1717
1718        cx.keystroke_interceptors
1719            .clone()
1720            .retain(&(), move |callback| {
1721                (callback)(
1722                    &KeystrokeEvent {
1723                        keystroke: key_down_event.keystroke.clone(),
1724                        action: None,
1725                        context_stack: context_stack.clone(),
1726                    },
1727                    self,
1728                    cx,
1729                )
1730            });
1731    }
1732
1733    /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
1734    /// that are currently on the stack to be returned to the app.
1735    pub fn defer(&self, cx: &mut App, f: impl FnOnce(&mut Window, &mut App) + 'static) {
1736        let handle = self.handle;
1737        cx.defer(move |cx| {
1738            handle.update(cx, |_, window, cx| f(window, cx)).ok();
1739        });
1740    }
1741
1742    /// Subscribe to events emitted by a entity.
1743    /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
1744    /// The callback will be invoked a handle to the emitting entity, the event, and a window context for the current window.
1745    pub fn observe<T: 'static>(
1746        &mut self,
1747        observed: &Entity<T>,
1748        cx: &mut App,
1749        mut on_notify: impl FnMut(Entity<T>, &mut Window, &mut App) + 'static,
1750    ) -> Subscription {
1751        let entity_id = observed.entity_id();
1752        let observed = observed.downgrade();
1753        let window_handle = self.handle;
1754        cx.new_observer(
1755            entity_id,
1756            Box::new(move |cx| {
1757                window_handle
1758                    .update(cx, |_, window, cx| {
1759                        if let Some(handle) = observed.upgrade() {
1760                            on_notify(handle, window, cx);
1761                            true
1762                        } else {
1763                            false
1764                        }
1765                    })
1766                    .unwrap_or(false)
1767            }),
1768        )
1769    }
1770
1771    /// Subscribe to events emitted by a entity.
1772    /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
1773    /// The callback will be invoked a handle to the emitting entity, the event, and a window context for the current window.
1774    pub fn subscribe<Emitter, Evt>(
1775        &mut self,
1776        entity: &Entity<Emitter>,
1777        cx: &mut App,
1778        mut on_event: impl FnMut(Entity<Emitter>, &Evt, &mut Window, &mut App) + 'static,
1779    ) -> Subscription
1780    where
1781        Emitter: EventEmitter<Evt>,
1782        Evt: 'static,
1783    {
1784        let entity_id = entity.entity_id();
1785        let handle = entity.downgrade();
1786        let window_handle = self.handle;
1787        cx.new_subscription(
1788            entity_id,
1789            (
1790                TypeId::of::<Evt>(),
1791                Box::new(move |event, cx| {
1792                    window_handle
1793                        .update(cx, |_, window, cx| {
1794                            if let Some(entity) = handle.upgrade() {
1795                                let event = event.downcast_ref().expect("invalid event type");
1796                                on_event(entity, event, window, cx);
1797                                true
1798                            } else {
1799                                false
1800                            }
1801                        })
1802                        .unwrap_or(false)
1803                }),
1804            ),
1805        )
1806    }
1807
1808    /// Register a callback to be invoked when the given `Entity` is released.
1809    pub fn observe_release<T>(
1810        &self,
1811        entity: &Entity<T>,
1812        cx: &mut App,
1813        mut on_release: impl FnOnce(&mut T, &mut Window, &mut App) + 'static,
1814    ) -> Subscription
1815    where
1816        T: 'static,
1817    {
1818        let entity_id = entity.entity_id();
1819        let window_handle = self.handle;
1820        let (subscription, activate) = cx.release_listeners.insert(
1821            entity_id,
1822            Box::new(move |entity, cx| {
1823                let entity = entity.downcast_mut().expect("invalid entity type");
1824                let _ = window_handle.update(cx, |_, window, cx| on_release(entity, window, cx));
1825            }),
1826        );
1827        activate();
1828        subscription
1829    }
1830
1831    /// Creates an [`AsyncWindowContext`], which has a static lifetime and can be held across
1832    /// await points in async code.
1833    pub fn to_async(&self, cx: &App) -> AsyncWindowContext {
1834        AsyncWindowContext::new_context(cx.to_async(), self.handle)
1835    }
1836
1837    /// Schedule the given closure to be run directly after the current frame is rendered.
1838    pub fn on_next_frame(&self, callback: impl FnOnce(&mut Window, &mut App) + 'static) {
1839        RefCell::borrow_mut(&self.next_frame_callbacks).push(Box::new(callback));
1840    }
1841
1842    /// Schedule a frame to be drawn on the next animation frame.
1843    ///
1844    /// This is useful for elements that need to animate continuously, such as a video player or an animated GIF.
1845    /// It will cause the window to redraw on the next frame, even if no other changes have occurred.
1846    ///
1847    /// If called from within a view, it will notify that view on the next frame. Otherwise, it will refresh the entire window.
1848    pub fn request_animation_frame(&self) {
1849        let entity = self.current_view();
1850        self.on_next_frame(move |_, cx| cx.notify(entity));
1851    }
1852
1853    /// Spawn the future returned by the given closure on the application thread pool.
1854    /// The closure is provided a handle to the current window and an `AsyncWindowContext` for
1855    /// use within your future.
1856    #[track_caller]
1857    pub fn spawn<AsyncFn, R>(&self, cx: &App, f: AsyncFn) -> Task<R>
1858    where
1859        R: 'static,
1860        AsyncFn: AsyncFnOnce(&mut AsyncWindowContext) -> R + 'static,
1861    {
1862        let handle = self.handle;
1863        cx.spawn(async move |app| {
1864            let mut async_window_cx = AsyncWindowContext::new_context(app.clone(), handle);
1865            f(&mut async_window_cx).await
1866        })
1867    }
1868
1869    /// Spawn the future returned by the given closure on the application thread
1870    /// pool, with the given priority. The closure is provided a handle to the
1871    /// current window and an `AsyncWindowContext` for use within your future.
1872    #[track_caller]
1873    pub fn spawn_with_priority<AsyncFn, R>(
1874        &self,
1875        priority: Priority,
1876        cx: &App,
1877        f: AsyncFn,
1878    ) -> Task<R>
1879    where
1880        R: 'static,
1881        AsyncFn: AsyncFnOnce(&mut AsyncWindowContext) -> R + 'static,
1882    {
1883        let handle = self.handle;
1884        cx.spawn_with_priority(priority, async move |app| {
1885            let mut async_window_cx = AsyncWindowContext::new_context(app.clone(), handle);
1886            f(&mut async_window_cx).await
1887        })
1888    }
1889
1890    fn bounds_changed(&mut self, cx: &mut App) {
1891        self.scale_factor = self.platform_window.scale_factor();
1892        self.viewport_size = self.platform_window.content_size();
1893        self.display_id = self.platform_window.display().map(|display| display.id());
1894
1895        self.refresh();
1896
1897        self.bounds_observers
1898            .clone()
1899            .retain(&(), |callback| callback(self, cx));
1900    }
1901
1902    /// Returns the bounds of the current window in the global coordinate space, which could span across multiple displays.
1903    pub fn bounds(&self) -> Bounds<Pixels> {
1904        self.platform_window.bounds()
1905    }
1906
1907    /// Renders the current frame's scene to a texture and returns the pixel data as an RGBA image.
1908    /// This does not present the frame to screen - useful for visual testing where we want
1909    /// to capture what would be rendered without displaying it or requiring the window to be visible.
1910    #[cfg(any(test, feature = "test-support"))]
1911    pub fn render_to_image(&self) -> anyhow::Result<image::RgbaImage> {
1912        self.platform_window
1913            .render_to_image(&self.rendered_frame.scene)
1914    }
1915
1916    /// Set the content size of the window.
1917    pub fn resize(&mut self, size: Size<Pixels>) {
1918        self.platform_window.resize(size);
1919    }
1920
1921    /// Returns whether or not the window is currently fullscreen
1922    pub fn is_fullscreen(&self) -> bool {
1923        self.platform_window.is_fullscreen()
1924    }
1925
1926    pub(crate) fn appearance_changed(&mut self, cx: &mut App) {
1927        self.appearance = self.platform_window.appearance();
1928
1929        self.appearance_observers
1930            .clone()
1931            .retain(&(), |callback| callback(self, cx));
1932    }
1933
1934    /// Returns the appearance of the current window.
1935    pub fn appearance(&self) -> WindowAppearance {
1936        self.appearance
1937    }
1938
1939    /// Returns the size of the drawable area within the window.
1940    pub fn viewport_size(&self) -> Size<Pixels> {
1941        self.viewport_size
1942    }
1943
1944    /// Returns whether this window is focused by the operating system (receiving key events).
1945    pub fn is_window_active(&self) -> bool {
1946        self.active.get()
1947    }
1948
1949    /// Returns whether this window is considered to be the window
1950    /// that currently owns the mouse cursor.
1951    /// On mac, this is equivalent to `is_window_active`.
1952    pub fn is_window_hovered(&self) -> bool {
1953        if cfg!(any(
1954            target_os = "windows",
1955            target_os = "linux",
1956            target_os = "freebsd"
1957        )) {
1958            self.hovered.get()
1959        } else {
1960            self.is_window_active()
1961        }
1962    }
1963
1964    /// Toggle zoom on the window.
1965    pub fn zoom_window(&self) {
1966        self.platform_window.zoom();
1967    }
1968
1969    /// Opens the native title bar context menu, useful when implementing client side decorations (Wayland and X11)
1970    pub fn show_window_menu(&self, position: Point<Pixels>) {
1971        self.platform_window.show_window_menu(position)
1972    }
1973
1974    /// Handle window movement for Linux and macOS.
1975    /// Tells the compositor to take control of window movement (Wayland and X11)
1976    ///
1977    /// Events may not be received during a move operation.
1978    pub fn start_window_move(&self) {
1979        self.platform_window.start_window_move()
1980    }
1981
1982    /// When using client side decorations, set this to the width of the invisible decorations (Wayland and X11)
1983    pub fn set_client_inset(&mut self, inset: Pixels) {
1984        self.client_inset = Some(inset);
1985        self.platform_window.set_client_inset(inset);
1986    }
1987
1988    /// Returns the client_inset value by [`Self::set_client_inset`].
1989    pub fn client_inset(&self) -> Option<Pixels> {
1990        self.client_inset
1991    }
1992
1993    /// Returns whether the title bar window controls need to be rendered by the application (Wayland and X11)
1994    pub fn window_decorations(&self) -> Decorations {
1995        self.platform_window.window_decorations()
1996    }
1997
1998    /// Returns which window controls are currently visible (Wayland)
1999    pub fn window_controls(&self) -> WindowControls {
2000        self.platform_window.window_controls()
2001    }
2002
2003    /// Updates the window's title at the platform level.
2004    pub fn set_window_title(&mut self, title: &str) {
2005        self.platform_window.set_title(title);
2006    }
2007
2008    /// Sets the application identifier.
2009    pub fn set_app_id(&mut self, app_id: &str) {
2010        self.platform_window.set_app_id(app_id);
2011    }
2012
2013    /// Sets the window background appearance.
2014    pub fn set_background_appearance(&self, background_appearance: WindowBackgroundAppearance) {
2015        self.platform_window
2016            .set_background_appearance(background_appearance);
2017    }
2018
2019    /// Mark the window as dirty at the platform level.
2020    pub fn set_window_edited(&mut self, edited: bool) {
2021        self.platform_window.set_edited(edited);
2022    }
2023
2024    /// Determine the display on which the window is visible.
2025    pub fn display(&self, cx: &App) -> Option<Rc<dyn PlatformDisplay>> {
2026        cx.platform
2027            .displays()
2028            .into_iter()
2029            .find(|display| Some(display.id()) == self.display_id)
2030    }
2031
2032    /// Show the platform character palette.
2033    pub fn show_character_palette(&self) {
2034        self.platform_window.show_character_palette();
2035    }
2036
2037    /// The scale factor of the display associated with the window. For example, it could
2038    /// return 2.0 for a "retina" display, indicating that each logical pixel should actually
2039    /// be rendered as two pixels on screen.
2040    pub fn scale_factor(&self) -> f32 {
2041        self.scale_factor
2042    }
2043
2044    /// The size of an em for the base font of the application. Adjusting this value allows the
2045    /// UI to scale, just like zooming a web page.
2046    pub fn rem_size(&self) -> Pixels {
2047        self.rem_size_override_stack
2048            .last()
2049            .copied()
2050            .unwrap_or(self.rem_size)
2051    }
2052
2053    /// Sets the size of an em for the base font of the application. Adjusting this value allows the
2054    /// UI to scale, just like zooming a web page.
2055    pub fn set_rem_size(&mut self, rem_size: impl Into<Pixels>) {
2056        self.rem_size = rem_size.into();
2057    }
2058
2059    /// Acquire a globally unique identifier for the given ElementId.
2060    /// Only valid for the duration of the provided closure.
2061    pub fn with_global_id<R>(
2062        &mut self,
2063        element_id: ElementId,
2064        f: impl FnOnce(&GlobalElementId, &mut Self) -> R,
2065    ) -> R {
2066        self.with_id(element_id, |this| {
2067            let global_id = GlobalElementId(Arc::from(&*this.element_id_stack));
2068
2069            f(&global_id, this)
2070        })
2071    }
2072
2073    /// Calls the provided closure with the element ID pushed on the stack.
2074    #[inline]
2075    pub fn with_id<R>(
2076        &mut self,
2077        element_id: impl Into<ElementId>,
2078        f: impl FnOnce(&mut Self) -> R,
2079    ) -> R {
2080        self.element_id_stack.push(element_id.into());
2081        let result = f(self);
2082        self.element_id_stack.pop();
2083        result
2084    }
2085
2086    /// Executes the provided function with the specified rem size.
2087    ///
2088    /// This method must only be called as part of element drawing.
2089    // This function is called in a highly recursive manner in editor
2090    // prepainting, make sure its inlined to reduce the stack burden
2091    #[inline]
2092    pub fn with_rem_size<F, R>(&mut self, rem_size: Option<impl Into<Pixels>>, f: F) -> R
2093    where
2094        F: FnOnce(&mut Self) -> R,
2095    {
2096        self.invalidator.debug_assert_paint_or_prepaint();
2097
2098        if let Some(rem_size) = rem_size {
2099            self.rem_size_override_stack.push(rem_size.into());
2100            let result = f(self);
2101            self.rem_size_override_stack.pop();
2102            result
2103        } else {
2104            f(self)
2105        }
2106    }
2107
2108    /// The line height associated with the current text style.
2109    pub fn line_height(&self) -> Pixels {
2110        self.text_style().line_height_in_pixels(self.rem_size())
2111    }
2112
2113    /// Call to prevent the default action of an event. Currently only used to prevent
2114    /// parent elements from becoming focused on mouse down.
2115    pub fn prevent_default(&mut self) {
2116        self.default_prevented = true;
2117    }
2118
2119    /// Obtain whether default has been prevented for the event currently being dispatched.
2120    pub fn default_prevented(&self) -> bool {
2121        self.default_prevented
2122    }
2123
2124    /// Determine whether the given action is available along the dispatch path to the currently focused element.
2125    pub fn is_action_available(&self, action: &dyn Action, cx: &App) -> bool {
2126        let node_id =
2127            self.focus_node_id_in_rendered_frame(self.focused(cx).map(|handle| handle.id));
2128        self.rendered_frame
2129            .dispatch_tree
2130            .is_action_available(action, node_id)
2131    }
2132
2133    /// Determine whether the given action is available along the dispatch path to the given focus_handle.
2134    pub fn is_action_available_in(&self, action: &dyn Action, focus_handle: &FocusHandle) -> bool {
2135        let node_id = self.focus_node_id_in_rendered_frame(Some(focus_handle.id));
2136        self.rendered_frame
2137            .dispatch_tree
2138            .is_action_available(action, node_id)
2139    }
2140
2141    /// The position of the mouse relative to the window.
2142    pub fn mouse_position(&self) -> Point<Pixels> {
2143        self.mouse_position
2144    }
2145
2146    /// The current state of the keyboard's modifiers
2147    pub fn modifiers(&self) -> Modifiers {
2148        self.modifiers
2149    }
2150
2151    /// Returns true if the last input event was keyboard-based (key press, tab navigation, etc.)
2152    /// This is used for focus-visible styling to show focus indicators only for keyboard navigation.
2153    pub fn last_input_was_keyboard(&self) -> bool {
2154        self.last_input_modality == InputModality::Keyboard
2155    }
2156
2157    /// The current state of the keyboard's capslock
2158    pub fn capslock(&self) -> Capslock {
2159        self.capslock
2160    }
2161
2162    fn complete_frame(&self) {
2163        self.platform_window.completed_frame();
2164    }
2165
2166    /// Produces a new frame and assigns it to `rendered_frame`. To actually show
2167    /// the contents of the new [`Scene`], use [`Self::present`].
2168    #[profiling::function]
2169    pub fn draw(&mut self, cx: &mut App) -> ArenaClearNeeded {
2170        // Set up the per-App arena for element allocation during this draw.
2171        // This ensures that multiple test Apps have isolated arenas.
2172        let _arena_scope = ElementArenaScope::enter(&cx.element_arena);
2173
2174        self.invalidate_entities();
2175        cx.entities.clear_accessed();
2176        debug_assert!(self.rendered_entity_stack.is_empty());
2177        self.invalidator.set_dirty(false);
2178        self.requested_autoscroll = None;
2179
2180        // Restore the previously-used input handler.
2181        if let Some(input_handler) = self.platform_window.take_input_handler() {
2182            self.rendered_frame.input_handlers.push(Some(input_handler));
2183        }
2184        if !cx.mode.skip_drawing() {
2185            self.draw_roots(cx);
2186        }
2187        self.dirty_views.clear();
2188        self.next_frame.window_active = self.active.get();
2189
2190        // Register requested input handler with the platform window.
2191        if let Some(input_handler) = self.next_frame.input_handlers.pop() {
2192            self.platform_window
2193                .set_input_handler(input_handler.unwrap());
2194        }
2195
2196        self.layout_engine.as_mut().unwrap().clear();
2197        self.text_system().finish_frame();
2198        self.next_frame.finish(&mut self.rendered_frame);
2199
2200        self.invalidator.set_phase(DrawPhase::Focus);
2201        let previous_focus_path = self.rendered_frame.focus_path();
2202        let previous_window_active = self.rendered_frame.window_active;
2203        mem::swap(&mut self.rendered_frame, &mut self.next_frame);
2204        self.next_frame.clear();
2205        let current_focus_path = self.rendered_frame.focus_path();
2206        let current_window_active = self.rendered_frame.window_active;
2207
2208        if previous_focus_path != current_focus_path
2209            || previous_window_active != current_window_active
2210        {
2211            if !previous_focus_path.is_empty() && current_focus_path.is_empty() {
2212                self.focus_lost_listeners
2213                    .clone()
2214                    .retain(&(), |listener| listener(self, cx));
2215            }
2216
2217            let event = WindowFocusEvent {
2218                previous_focus_path: if previous_window_active {
2219                    previous_focus_path
2220                } else {
2221                    Default::default()
2222                },
2223                current_focus_path: if current_window_active {
2224                    current_focus_path
2225                } else {
2226                    Default::default()
2227                },
2228            };
2229            self.focus_listeners
2230                .clone()
2231                .retain(&(), |listener| listener(&event, self, cx));
2232        }
2233
2234        debug_assert!(self.rendered_entity_stack.is_empty());
2235        self.record_entities_accessed(cx);
2236        self.reset_cursor_style(cx);
2237        self.refreshing = false;
2238        self.invalidator.set_phase(DrawPhase::None);
2239        self.needs_present.set(true);
2240
2241        ArenaClearNeeded::new(&cx.element_arena)
2242    }
2243
2244    fn record_entities_accessed(&mut self, cx: &mut App) {
2245        let mut entities_ref = cx.entities.accessed_entities.get_mut();
2246        let mut entities = mem::take(entities_ref.deref_mut());
2247        let handle = self.handle;
2248        cx.record_entities_accessed(
2249            handle,
2250            // Try moving window invalidator into the Window
2251            self.invalidator.clone(),
2252            &entities,
2253        );
2254        let mut entities_ref = cx.entities.accessed_entities.get_mut();
2255        mem::swap(&mut entities, entities_ref.deref_mut());
2256    }
2257
2258    fn invalidate_entities(&mut self) {
2259        let mut views = self.invalidator.take_views();
2260        for entity in views.drain() {
2261            self.mark_view_dirty(entity);
2262        }
2263        self.invalidator.replace_views(views);
2264    }
2265
2266    #[profiling::function]
2267    fn present(&self) {
2268        self.platform_window.draw(&self.rendered_frame.scene);
2269        self.needs_present.set(false);
2270        profiling::finish_frame!();
2271    }
2272
2273    fn draw_roots(&mut self, cx: &mut App) {
2274        self.invalidator.set_phase(DrawPhase::Prepaint);
2275        self.tooltip_bounds.take();
2276
2277        let _inspector_width: Pixels = rems(30.0).to_pixels(self.rem_size());
2278        let root_size = {
2279            #[cfg(any(feature = "inspector", debug_assertions))]
2280            {
2281                if self.inspector.is_some() {
2282                    let mut size = self.viewport_size;
2283                    size.width = (size.width - _inspector_width).max(px(0.0));
2284                    size
2285                } else {
2286                    self.viewport_size
2287                }
2288            }
2289            #[cfg(not(any(feature = "inspector", debug_assertions)))]
2290            {
2291                self.viewport_size
2292            }
2293        };
2294
2295        // Layout all root elements.
2296        let mut root_element = self.root.as_ref().unwrap().clone().into_any();
2297        root_element.prepaint_as_root(Point::default(), root_size.into(), self, cx);
2298
2299        #[cfg(any(feature = "inspector", debug_assertions))]
2300        let inspector_element = self.prepaint_inspector(_inspector_width, cx);
2301
2302        let mut sorted_deferred_draws =
2303            (0..self.next_frame.deferred_draws.len()).collect::<SmallVec<[_; 8]>>();
2304        sorted_deferred_draws.sort_by_key(|ix| self.next_frame.deferred_draws[*ix].priority);
2305        self.prepaint_deferred_draws(&sorted_deferred_draws, cx);
2306
2307        let mut prompt_element = None;
2308        let mut active_drag_element = None;
2309        let mut tooltip_element = None;
2310        if let Some(prompt) = self.prompt.take() {
2311            let mut element = prompt.view.any_view().into_any();
2312            element.prepaint_as_root(Point::default(), root_size.into(), self, cx);
2313            prompt_element = Some(element);
2314            self.prompt = Some(prompt);
2315        } else if let Some(active_drag) = cx.active_drag.take() {
2316            let mut element = active_drag.view.clone().into_any();
2317            let offset = self.mouse_position() - active_drag.cursor_offset;
2318            element.prepaint_as_root(offset, AvailableSpace::min_size(), self, cx);
2319            active_drag_element = Some(element);
2320            cx.active_drag = Some(active_drag);
2321        } else {
2322            tooltip_element = self.prepaint_tooltip(cx);
2323        }
2324
2325        self.mouse_hit_test = self.next_frame.hit_test(self.mouse_position);
2326
2327        // Now actually paint the elements.
2328        self.invalidator.set_phase(DrawPhase::Paint);
2329        root_element.paint(self, cx);
2330
2331        #[cfg(any(feature = "inspector", debug_assertions))]
2332        self.paint_inspector(inspector_element, cx);
2333
2334        self.paint_deferred_draws(&sorted_deferred_draws, cx);
2335
2336        if let Some(mut prompt_element) = prompt_element {
2337            prompt_element.paint(self, cx);
2338        } else if let Some(mut drag_element) = active_drag_element {
2339            drag_element.paint(self, cx);
2340        } else if let Some(mut tooltip_element) = tooltip_element {
2341            tooltip_element.paint(self, cx);
2342        }
2343
2344        #[cfg(any(feature = "inspector", debug_assertions))]
2345        self.paint_inspector_hitbox(cx);
2346    }
2347
2348    fn prepaint_tooltip(&mut self, cx: &mut App) -> Option<AnyElement> {
2349        // Use indexing instead of iteration to avoid borrowing self for the duration of the loop.
2350        for tooltip_request_index in (0..self.next_frame.tooltip_requests.len()).rev() {
2351            let Some(Some(tooltip_request)) = self
2352                .next_frame
2353                .tooltip_requests
2354                .get(tooltip_request_index)
2355                .cloned()
2356            else {
2357                log::error!("Unexpectedly absent TooltipRequest");
2358                continue;
2359            };
2360            let mut element = tooltip_request.tooltip.view.clone().into_any();
2361            let mouse_position = tooltip_request.tooltip.mouse_position;
2362            let tooltip_size = element.layout_as_root(AvailableSpace::min_size(), self, cx);
2363
2364            let mut tooltip_bounds =
2365                Bounds::new(mouse_position + point(px(1.), px(1.)), tooltip_size);
2366            let window_bounds = Bounds {
2367                origin: Point::default(),
2368                size: self.viewport_size(),
2369            };
2370
2371            if tooltip_bounds.right() > window_bounds.right() {
2372                let new_x = mouse_position.x - tooltip_bounds.size.width - px(1.);
2373                if new_x >= Pixels::ZERO {
2374                    tooltip_bounds.origin.x = new_x;
2375                } else {
2376                    tooltip_bounds.origin.x = cmp::max(
2377                        Pixels::ZERO,
2378                        tooltip_bounds.origin.x - tooltip_bounds.right() - window_bounds.right(),
2379                    );
2380                }
2381            }
2382
2383            if tooltip_bounds.bottom() > window_bounds.bottom() {
2384                let new_y = mouse_position.y - tooltip_bounds.size.height - px(1.);
2385                if new_y >= Pixels::ZERO {
2386                    tooltip_bounds.origin.y = new_y;
2387                } else {
2388                    tooltip_bounds.origin.y = cmp::max(
2389                        Pixels::ZERO,
2390                        tooltip_bounds.origin.y - tooltip_bounds.bottom() - window_bounds.bottom(),
2391                    );
2392                }
2393            }
2394
2395            // It's possible for an element to have an active tooltip while not being painted (e.g.
2396            // via the `visible_on_hover` method). Since mouse listeners are not active in this
2397            // case, instead update the tooltip's visibility here.
2398            let is_visible =
2399                (tooltip_request.tooltip.check_visible_and_update)(tooltip_bounds, self, cx);
2400            if !is_visible {
2401                continue;
2402            }
2403
2404            self.with_absolute_element_offset(tooltip_bounds.origin, |window| {
2405                element.prepaint(window, cx)
2406            });
2407
2408            self.tooltip_bounds = Some(TooltipBounds {
2409                id: tooltip_request.id,
2410                bounds: tooltip_bounds,
2411            });
2412            return Some(element);
2413        }
2414        None
2415    }
2416
2417    fn prepaint_deferred_draws(&mut self, deferred_draw_indices: &[usize], cx: &mut App) {
2418        assert_eq!(self.element_id_stack.len(), 0);
2419
2420        let mut deferred_draws = mem::take(&mut self.next_frame.deferred_draws);
2421        for deferred_draw_ix in deferred_draw_indices {
2422            let deferred_draw = &mut deferred_draws[*deferred_draw_ix];
2423            self.element_id_stack
2424                .clone_from(&deferred_draw.element_id_stack);
2425            self.text_style_stack
2426                .clone_from(&deferred_draw.text_style_stack);
2427            self.next_frame
2428                .dispatch_tree
2429                .set_active_node(deferred_draw.parent_node);
2430
2431            let prepaint_start = self.prepaint_index();
2432            if let Some(element) = deferred_draw.element.as_mut() {
2433                self.with_rendered_view(deferred_draw.current_view, |window| {
2434                    window.with_rem_size(Some(deferred_draw.rem_size), |window| {
2435                        window.with_absolute_element_offset(
2436                            deferred_draw.absolute_offset,
2437                            |window| {
2438                                element.prepaint(window, cx);
2439                            },
2440                        );
2441                    });
2442                })
2443            } else {
2444                self.reuse_prepaint(deferred_draw.prepaint_range.clone());
2445            }
2446            let prepaint_end = self.prepaint_index();
2447            deferred_draw.prepaint_range = prepaint_start..prepaint_end;
2448        }
2449        assert_eq!(
2450            self.next_frame.deferred_draws.len(),
2451            0,
2452            "cannot call defer_draw during deferred drawing"
2453        );
2454        self.next_frame.deferred_draws = deferred_draws;
2455        self.element_id_stack.clear();
2456        self.text_style_stack.clear();
2457    }
2458
2459    fn paint_deferred_draws(&mut self, deferred_draw_indices: &[usize], cx: &mut App) {
2460        assert_eq!(self.element_id_stack.len(), 0);
2461
2462        let mut deferred_draws = mem::take(&mut self.next_frame.deferred_draws);
2463        for deferred_draw_ix in deferred_draw_indices {
2464            let mut deferred_draw = &mut deferred_draws[*deferred_draw_ix];
2465            self.element_id_stack
2466                .clone_from(&deferred_draw.element_id_stack);
2467            self.next_frame
2468                .dispatch_tree
2469                .set_active_node(deferred_draw.parent_node);
2470
2471            let paint_start = self.paint_index();
2472            if let Some(element) = deferred_draw.element.as_mut() {
2473                self.with_rendered_view(deferred_draw.current_view, |window| {
2474                    window.with_rem_size(Some(deferred_draw.rem_size), |window| {
2475                        element.paint(window, cx);
2476                    })
2477                })
2478            } else {
2479                self.reuse_paint(deferred_draw.paint_range.clone());
2480            }
2481            let paint_end = self.paint_index();
2482            deferred_draw.paint_range = paint_start..paint_end;
2483        }
2484        self.next_frame.deferred_draws = deferred_draws;
2485        self.element_id_stack.clear();
2486    }
2487
2488    pub(crate) fn prepaint_index(&self) -> PrepaintStateIndex {
2489        PrepaintStateIndex {
2490            hitboxes_index: self.next_frame.hitboxes.len(),
2491            tooltips_index: self.next_frame.tooltip_requests.len(),
2492            deferred_draws_index: self.next_frame.deferred_draws.len(),
2493            dispatch_tree_index: self.next_frame.dispatch_tree.len(),
2494            accessed_element_states_index: self.next_frame.accessed_element_states.len(),
2495            line_layout_index: self.text_system.layout_index(),
2496        }
2497    }
2498
2499    pub(crate) fn reuse_prepaint(&mut self, range: Range<PrepaintStateIndex>) {
2500        self.next_frame.hitboxes.extend(
2501            self.rendered_frame.hitboxes[range.start.hitboxes_index..range.end.hitboxes_index]
2502                .iter()
2503                .cloned(),
2504        );
2505        self.next_frame.tooltip_requests.extend(
2506            self.rendered_frame.tooltip_requests
2507                [range.start.tooltips_index..range.end.tooltips_index]
2508                .iter_mut()
2509                .map(|request| request.take()),
2510        );
2511        self.next_frame.accessed_element_states.extend(
2512            self.rendered_frame.accessed_element_states[range.start.accessed_element_states_index
2513                ..range.end.accessed_element_states_index]
2514                .iter()
2515                .map(|(id, type_id)| (id.clone(), *type_id)),
2516        );
2517        self.text_system
2518            .reuse_layouts(range.start.line_layout_index..range.end.line_layout_index);
2519
2520        let reused_subtree = self.next_frame.dispatch_tree.reuse_subtree(
2521            range.start.dispatch_tree_index..range.end.dispatch_tree_index,
2522            &mut self.rendered_frame.dispatch_tree,
2523            self.focus,
2524        );
2525
2526        if reused_subtree.contains_focus() {
2527            self.next_frame.focus = self.focus;
2528        }
2529
2530        self.next_frame.deferred_draws.extend(
2531            self.rendered_frame.deferred_draws
2532                [range.start.deferred_draws_index..range.end.deferred_draws_index]
2533                .iter()
2534                .map(|deferred_draw| DeferredDraw {
2535                    current_view: deferred_draw.current_view,
2536                    parent_node: reused_subtree.refresh_node_id(deferred_draw.parent_node),
2537                    element_id_stack: deferred_draw.element_id_stack.clone(),
2538                    text_style_stack: deferred_draw.text_style_stack.clone(),
2539                    rem_size: deferred_draw.rem_size,
2540                    priority: deferred_draw.priority,
2541                    element: None,
2542                    absolute_offset: deferred_draw.absolute_offset,
2543                    prepaint_range: deferred_draw.prepaint_range.clone(),
2544                    paint_range: deferred_draw.paint_range.clone(),
2545                }),
2546        );
2547    }
2548
2549    pub(crate) fn paint_index(&self) -> PaintIndex {
2550        PaintIndex {
2551            scene_index: self.next_frame.scene.len(),
2552            mouse_listeners_index: self.next_frame.mouse_listeners.len(),
2553            input_handlers_index: self.next_frame.input_handlers.len(),
2554            cursor_styles_index: self.next_frame.cursor_styles.len(),
2555            accessed_element_states_index: self.next_frame.accessed_element_states.len(),
2556            tab_handle_index: self.next_frame.tab_stops.paint_index(),
2557            line_layout_index: self.text_system.layout_index(),
2558        }
2559    }
2560
2561    pub(crate) fn reuse_paint(&mut self, range: Range<PaintIndex>) {
2562        self.next_frame.cursor_styles.extend(
2563            self.rendered_frame.cursor_styles
2564                [range.start.cursor_styles_index..range.end.cursor_styles_index]
2565                .iter()
2566                .cloned(),
2567        );
2568        self.next_frame.input_handlers.extend(
2569            self.rendered_frame.input_handlers
2570                [range.start.input_handlers_index..range.end.input_handlers_index]
2571                .iter_mut()
2572                .map(|handler| handler.take()),
2573        );
2574        self.next_frame.mouse_listeners.extend(
2575            self.rendered_frame.mouse_listeners
2576                [range.start.mouse_listeners_index..range.end.mouse_listeners_index]
2577                .iter_mut()
2578                .map(|listener| listener.take()),
2579        );
2580        self.next_frame.accessed_element_states.extend(
2581            self.rendered_frame.accessed_element_states[range.start.accessed_element_states_index
2582                ..range.end.accessed_element_states_index]
2583                .iter()
2584                .map(|(id, type_id)| (id.clone(), *type_id)),
2585        );
2586        self.next_frame.tab_stops.replay(
2587            &self.rendered_frame.tab_stops.insertion_history
2588                [range.start.tab_handle_index..range.end.tab_handle_index],
2589        );
2590
2591        self.text_system
2592            .reuse_layouts(range.start.line_layout_index..range.end.line_layout_index);
2593        self.next_frame.scene.replay(
2594            range.start.scene_index..range.end.scene_index,
2595            &self.rendered_frame.scene,
2596        );
2597    }
2598
2599    /// Push a text style onto the stack, and call a function with that style active.
2600    /// Use [`Window::text_style`] to get the current, combined text style. This method
2601    /// should only be called as part of element drawing.
2602    // This function is called in a highly recursive manner in editor
2603    // prepainting, make sure its inlined to reduce the stack burden
2604    #[inline]
2605    pub fn with_text_style<F, R>(&mut self, style: Option<TextStyleRefinement>, f: F) -> R
2606    where
2607        F: FnOnce(&mut Self) -> R,
2608    {
2609        self.invalidator.debug_assert_paint_or_prepaint();
2610        if let Some(style) = style {
2611            self.text_style_stack.push(style);
2612            let result = f(self);
2613            self.text_style_stack.pop();
2614            result
2615        } else {
2616            f(self)
2617        }
2618    }
2619
2620    /// Updates the cursor style at the platform level. This method should only be called
2621    /// during the paint phase of element drawing.
2622    pub fn set_cursor_style(&mut self, style: CursorStyle, hitbox: &Hitbox) {
2623        self.invalidator.debug_assert_paint();
2624        self.next_frame.cursor_styles.push(CursorStyleRequest {
2625            hitbox_id: Some(hitbox.id),
2626            style,
2627        });
2628    }
2629
2630    /// Updates the cursor style for the entire window at the platform level. A cursor
2631    /// style using this method will have precedence over any cursor style set using
2632    /// `set_cursor_style`. This method should only be called during the paint
2633    /// phase of element drawing.
2634    pub fn set_window_cursor_style(&mut self, style: CursorStyle) {
2635        self.invalidator.debug_assert_paint();
2636        self.next_frame.cursor_styles.push(CursorStyleRequest {
2637            hitbox_id: None,
2638            style,
2639        })
2640    }
2641
2642    /// Sets a tooltip to be rendered for the upcoming frame. This method should only be called
2643    /// during the paint phase of element drawing.
2644    pub fn set_tooltip(&mut self, tooltip: AnyTooltip) -> TooltipId {
2645        self.invalidator.debug_assert_prepaint();
2646        let id = TooltipId(post_inc(&mut self.next_tooltip_id.0));
2647        self.next_frame
2648            .tooltip_requests
2649            .push(Some(TooltipRequest { id, tooltip }));
2650        id
2651    }
2652
2653    /// Invoke the given function with the given content mask after intersecting it
2654    /// with the current mask. This method should only be called during element drawing.
2655    // This function is called in a highly recursive manner in editor
2656    // prepainting, make sure its inlined to reduce the stack burden
2657    #[inline]
2658    pub fn with_content_mask<R>(
2659        &mut self,
2660        mask: Option<ContentMask<Pixels>>,
2661        f: impl FnOnce(&mut Self) -> R,
2662    ) -> R {
2663        self.invalidator.debug_assert_paint_or_prepaint();
2664        if let Some(mask) = mask {
2665            let mask = mask.intersect(&self.content_mask());
2666            self.content_mask_stack.push(mask);
2667            let result = f(self);
2668            self.content_mask_stack.pop();
2669            result
2670        } else {
2671            f(self)
2672        }
2673    }
2674
2675    /// Updates the global element offset relative to the current offset. This is used to implement
2676    /// scrolling. This method should only be called during the prepaint phase of element drawing.
2677    pub fn with_element_offset<R>(
2678        &mut self,
2679        offset: Point<Pixels>,
2680        f: impl FnOnce(&mut Self) -> R,
2681    ) -> R {
2682        self.invalidator.debug_assert_prepaint();
2683
2684        if offset.is_zero() {
2685            return f(self);
2686        };
2687
2688        let abs_offset = self.element_offset() + offset;
2689        self.with_absolute_element_offset(abs_offset, f)
2690    }
2691
2692    /// Updates the global element offset based on the given offset. This is used to implement
2693    /// drag handles and other manual painting of elements. This method should only be called during
2694    /// the prepaint phase of element drawing.
2695    pub fn with_absolute_element_offset<R>(
2696        &mut self,
2697        offset: Point<Pixels>,
2698        f: impl FnOnce(&mut Self) -> R,
2699    ) -> R {
2700        self.invalidator.debug_assert_prepaint();
2701        self.element_offset_stack.push(offset);
2702        let result = f(self);
2703        self.element_offset_stack.pop();
2704        result
2705    }
2706
2707    pub(crate) fn with_element_opacity<R>(
2708        &mut self,
2709        opacity: Option<f32>,
2710        f: impl FnOnce(&mut Self) -> R,
2711    ) -> R {
2712        self.invalidator.debug_assert_paint_or_prepaint();
2713
2714        let Some(opacity) = opacity else {
2715            return f(self);
2716        };
2717
2718        let previous_opacity = self.element_opacity;
2719        self.element_opacity = previous_opacity * opacity;
2720        let result = f(self);
2721        self.element_opacity = previous_opacity;
2722        result
2723    }
2724
2725    /// Perform prepaint on child elements in a "retryable" manner, so that any side effects
2726    /// of prepaints can be discarded before prepainting again. This is used to support autoscroll
2727    /// where we need to prepaint children to detect the autoscroll bounds, then adjust the
2728    /// element offset and prepaint again. See [`crate::List`] for an example. This method should only be
2729    /// called during the prepaint phase of element drawing.
2730    pub fn transact<T, U>(&mut self, f: impl FnOnce(&mut Self) -> Result<T, U>) -> Result<T, U> {
2731        self.invalidator.debug_assert_prepaint();
2732        let index = self.prepaint_index();
2733        let result = f(self);
2734        if result.is_err() {
2735            self.next_frame.hitboxes.truncate(index.hitboxes_index);
2736            self.next_frame
2737                .tooltip_requests
2738                .truncate(index.tooltips_index);
2739            self.next_frame
2740                .deferred_draws
2741                .truncate(index.deferred_draws_index);
2742            self.next_frame
2743                .dispatch_tree
2744                .truncate(index.dispatch_tree_index);
2745            self.next_frame
2746                .accessed_element_states
2747                .truncate(index.accessed_element_states_index);
2748            self.text_system.truncate_layouts(index.line_layout_index);
2749        }
2750        result
2751    }
2752
2753    /// When you call this method during [`Element::prepaint`], containing elements will attempt to
2754    /// scroll to cause the specified bounds to become visible. When they decide to autoscroll, they will call
2755    /// [`Element::prepaint`] again with a new set of bounds. See [`crate::List`] for an example of an element
2756    /// that supports this method being called on the elements it contains. This method should only be
2757    /// called during the prepaint phase of element drawing.
2758    pub fn request_autoscroll(&mut self, bounds: Bounds<Pixels>) {
2759        self.invalidator.debug_assert_prepaint();
2760        self.requested_autoscroll = Some(bounds);
2761    }
2762
2763    /// This method can be called from a containing element such as [`crate::List`] to support the autoscroll behavior
2764    /// described in [`Self::request_autoscroll`].
2765    pub fn take_autoscroll(&mut self) -> Option<Bounds<Pixels>> {
2766        self.invalidator.debug_assert_prepaint();
2767        self.requested_autoscroll.take()
2768    }
2769
2770    /// Asynchronously load an asset, if the asset hasn't finished loading this will return None.
2771    /// Your view will be re-drawn once the asset has finished loading.
2772    ///
2773    /// Note that the multiple calls to this method will only result in one `Asset::load` call at a
2774    /// time.
2775    pub fn use_asset<A: Asset>(&mut self, source: &A::Source, cx: &mut App) -> Option<A::Output> {
2776        let (task, is_first) = cx.fetch_asset::<A>(source);
2777        task.clone().now_or_never().or_else(|| {
2778            if is_first {
2779                let entity_id = self.current_view();
2780                self.spawn(cx, {
2781                    let task = task.clone();
2782                    async move |cx| {
2783                        task.await;
2784
2785                        cx.on_next_frame(move |_, cx| {
2786                            cx.notify(entity_id);
2787                        });
2788                    }
2789                })
2790                .detach();
2791            }
2792
2793            None
2794        })
2795    }
2796
2797    /// Asynchronously load an asset, if the asset hasn't finished loading or doesn't exist this will return None.
2798    /// Your view will not be re-drawn once the asset has finished loading.
2799    ///
2800    /// Note that the multiple calls to this method will only result in one `Asset::load` call at a
2801    /// time.
2802    pub fn get_asset<A: Asset>(&mut self, source: &A::Source, cx: &mut App) -> Option<A::Output> {
2803        let (task, _) = cx.fetch_asset::<A>(source);
2804        task.now_or_never()
2805    }
2806    /// Obtain the current element offset. This method should only be called during the
2807    /// prepaint phase of element drawing.
2808    pub fn element_offset(&self) -> Point<Pixels> {
2809        self.invalidator.debug_assert_prepaint();
2810        self.element_offset_stack
2811            .last()
2812            .copied()
2813            .unwrap_or_default()
2814    }
2815
2816    /// Obtain the current element opacity. This method should only be called during the
2817    /// prepaint phase of element drawing.
2818    #[inline]
2819    pub(crate) fn element_opacity(&self) -> f32 {
2820        self.invalidator.debug_assert_paint_or_prepaint();
2821        self.element_opacity
2822    }
2823
2824    /// Obtain the current content mask. This method should only be called during element drawing.
2825    pub fn content_mask(&self) -> ContentMask<Pixels> {
2826        self.invalidator.debug_assert_paint_or_prepaint();
2827        self.content_mask_stack
2828            .last()
2829            .cloned()
2830            .unwrap_or_else(|| ContentMask {
2831                bounds: Bounds {
2832                    origin: Point::default(),
2833                    size: self.viewport_size,
2834                },
2835            })
2836    }
2837
2838    /// Provide elements in the called function with a new namespace in which their identifiers must be unique.
2839    /// This can be used within a custom element to distinguish multiple sets of child elements.
2840    pub fn with_element_namespace<R>(
2841        &mut self,
2842        element_id: impl Into<ElementId>,
2843        f: impl FnOnce(&mut Self) -> R,
2844    ) -> R {
2845        self.element_id_stack.push(element_id.into());
2846        let result = f(self);
2847        self.element_id_stack.pop();
2848        result
2849    }
2850
2851    /// Use a piece of state that exists as long this element is being rendered in consecutive frames.
2852    pub fn use_keyed_state<S: 'static>(
2853        &mut self,
2854        key: impl Into<ElementId>,
2855        cx: &mut App,
2856        init: impl FnOnce(&mut Self, &mut Context<S>) -> S,
2857    ) -> Entity<S> {
2858        let current_view = self.current_view();
2859        self.with_global_id(key.into(), |global_id, window| {
2860            window.with_element_state(global_id, |state: Option<Entity<S>>, window| {
2861                if let Some(state) = state {
2862                    (state.clone(), state)
2863                } else {
2864                    let new_state = cx.new(|cx| init(window, cx));
2865                    cx.observe(&new_state, move |_, cx| {
2866                        cx.notify(current_view);
2867                    })
2868                    .detach();
2869                    (new_state.clone(), new_state)
2870                }
2871            })
2872        })
2873    }
2874
2875    /// Use a piece of state that exists as long this element is being rendered in consecutive frames, without needing to specify a key
2876    ///
2877    /// NOTE: This method uses the location of the caller to generate an ID for this state.
2878    ///       If this is not sufficient to identify your state (e.g. you're rendering a list item),
2879    ///       you can provide a custom ElementID using the `use_keyed_state` method.
2880    #[track_caller]
2881    pub fn use_state<S: 'static>(
2882        &mut self,
2883        cx: &mut App,
2884        init: impl FnOnce(&mut Self, &mut Context<S>) -> S,
2885    ) -> Entity<S> {
2886        self.use_keyed_state(
2887            ElementId::CodeLocation(*core::panic::Location::caller()),
2888            cx,
2889            init,
2890        )
2891    }
2892
2893    /// Updates or initializes state for an element with the given id that lives across multiple
2894    /// frames. If an element with this ID existed in the rendered frame, its state will be passed
2895    /// to the given closure. The state returned by the closure will be stored so it can be referenced
2896    /// when drawing the next frame. This method should only be called as part of element drawing.
2897    pub fn with_element_state<S, R>(
2898        &mut self,
2899        global_id: &GlobalElementId,
2900        f: impl FnOnce(Option<S>, &mut Self) -> (R, S),
2901    ) -> R
2902    where
2903        S: 'static,
2904    {
2905        self.invalidator.debug_assert_paint_or_prepaint();
2906
2907        let key = (global_id.clone(), TypeId::of::<S>());
2908        self.next_frame.accessed_element_states.push(key.clone());
2909
2910        if let Some(any) = self
2911            .next_frame
2912            .element_states
2913            .remove(&key)
2914            .or_else(|| self.rendered_frame.element_states.remove(&key))
2915        {
2916            let ElementStateBox {
2917                inner,
2918                #[cfg(debug_assertions)]
2919                type_name,
2920            } = any;
2921            // Using the extra inner option to avoid needing to reallocate a new box.
2922            let mut state_box = inner
2923                .downcast::<Option<S>>()
2924                .map_err(|_| {
2925                    #[cfg(debug_assertions)]
2926                    {
2927                        anyhow::anyhow!(
2928                            "invalid element state type for id, requested {:?}, actual: {:?}",
2929                            std::any::type_name::<S>(),
2930                            type_name
2931                        )
2932                    }
2933
2934                    #[cfg(not(debug_assertions))]
2935                    {
2936                        anyhow::anyhow!(
2937                            "invalid element state type for id, requested {:?}",
2938                            std::any::type_name::<S>(),
2939                        )
2940                    }
2941                })
2942                .unwrap();
2943
2944            let state = state_box.take().expect(
2945                "reentrant call to with_element_state for the same state type and element id",
2946            );
2947            let (result, state) = f(Some(state), self);
2948            state_box.replace(state);
2949            self.next_frame.element_states.insert(
2950                key,
2951                ElementStateBox {
2952                    inner: state_box,
2953                    #[cfg(debug_assertions)]
2954                    type_name,
2955                },
2956            );
2957            result
2958        } else {
2959            let (result, state) = f(None, self);
2960            self.next_frame.element_states.insert(
2961                key,
2962                ElementStateBox {
2963                    inner: Box::new(Some(state)),
2964                    #[cfg(debug_assertions)]
2965                    type_name: std::any::type_name::<S>(),
2966                },
2967            );
2968            result
2969        }
2970    }
2971
2972    /// A variant of `with_element_state` that allows the element's id to be optional. This is a convenience
2973    /// method for elements where the element id may or may not be assigned. Prefer using `with_element_state`
2974    /// when the element is guaranteed to have an id.
2975    ///
2976    /// The first option means 'no ID provided'
2977    /// The second option means 'not yet initialized'
2978    pub fn with_optional_element_state<S, R>(
2979        &mut self,
2980        global_id: Option<&GlobalElementId>,
2981        f: impl FnOnce(Option<Option<S>>, &mut Self) -> (R, Option<S>),
2982    ) -> R
2983    where
2984        S: 'static,
2985    {
2986        self.invalidator.debug_assert_paint_or_prepaint();
2987
2988        if let Some(global_id) = global_id {
2989            self.with_element_state(global_id, |state, cx| {
2990                let (result, state) = f(Some(state), cx);
2991                let state =
2992                    state.expect("you must return some state when you pass some element id");
2993                (result, state)
2994            })
2995        } else {
2996            let (result, state) = f(None, self);
2997            debug_assert!(
2998                state.is_none(),
2999                "you must not return an element state when passing None for the global id"
3000            );
3001            result
3002        }
3003    }
3004
3005    /// Executes the given closure within the context of a tab group.
3006    #[inline]
3007    pub fn with_tab_group<R>(&mut self, index: Option<isize>, f: impl FnOnce(&mut Self) -> R) -> R {
3008        if let Some(index) = index {
3009            self.next_frame.tab_stops.begin_group(index);
3010            let result = f(self);
3011            self.next_frame.tab_stops.end_group();
3012            result
3013        } else {
3014            f(self)
3015        }
3016    }
3017
3018    /// Defers the drawing of the given element, scheduling it to be painted on top of the currently-drawn tree
3019    /// at a later time. The `priority` parameter determines the drawing order relative to other deferred elements,
3020    /// with higher values being drawn on top.
3021    ///
3022    /// This method should only be called as part of the prepaint phase of element drawing.
3023    pub fn defer_draw(
3024        &mut self,
3025        element: AnyElement,
3026        absolute_offset: Point<Pixels>,
3027        priority: usize,
3028    ) {
3029        self.invalidator.debug_assert_prepaint();
3030        let parent_node = self.next_frame.dispatch_tree.active_node_id().unwrap();
3031        self.next_frame.deferred_draws.push(DeferredDraw {
3032            current_view: self.current_view(),
3033            parent_node,
3034            element_id_stack: self.element_id_stack.clone(),
3035            text_style_stack: self.text_style_stack.clone(),
3036            rem_size: self.rem_size(),
3037            priority,
3038            element: Some(element),
3039            absolute_offset,
3040            prepaint_range: PrepaintStateIndex::default()..PrepaintStateIndex::default(),
3041            paint_range: PaintIndex::default()..PaintIndex::default(),
3042        });
3043    }
3044
3045    /// Creates a new painting layer for the specified bounds. A "layer" is a batch
3046    /// of geometry that are non-overlapping and have the same draw order. This is typically used
3047    /// for performance reasons.
3048    ///
3049    /// This method should only be called as part of the paint phase of element drawing.
3050    pub fn paint_layer<R>(&mut self, bounds: Bounds<Pixels>, f: impl FnOnce(&mut Self) -> R) -> R {
3051        self.invalidator.debug_assert_paint();
3052
3053        let scale_factor = self.scale_factor();
3054        let content_mask = self.content_mask();
3055        let clipped_bounds = bounds.intersect(&content_mask.bounds);
3056        if !clipped_bounds.is_empty() {
3057            self.next_frame
3058                .scene
3059                .push_layer(clipped_bounds.scale(scale_factor));
3060        }
3061
3062        let result = f(self);
3063
3064        if !clipped_bounds.is_empty() {
3065            self.next_frame.scene.pop_layer();
3066        }
3067
3068        result
3069    }
3070
3071    /// Paint one or more drop shadows into the scene for the next frame at the current z-index.
3072    ///
3073    /// This method should only be called as part of the paint phase of element drawing.
3074    pub fn paint_shadows(
3075        &mut self,
3076        bounds: Bounds<Pixels>,
3077        corner_radii: Corners<Pixels>,
3078        shadows: &[BoxShadow],
3079    ) {
3080        self.invalidator.debug_assert_paint();
3081
3082        let scale_factor = self.scale_factor();
3083        let content_mask = self.content_mask();
3084        let opacity = self.element_opacity();
3085        for shadow in shadows {
3086            let shadow_bounds = (bounds + shadow.offset).dilate(shadow.spread_radius);
3087            self.next_frame.scene.insert_primitive(Shadow {
3088                order: 0,
3089                blur_radius: shadow.blur_radius.scale(scale_factor),
3090                bounds: shadow_bounds.scale(scale_factor),
3091                content_mask: content_mask.scale(scale_factor),
3092                corner_radii: corner_radii.scale(scale_factor),
3093                color: shadow.color.opacity(opacity),
3094            });
3095        }
3096    }
3097
3098    /// Paint one or more quads into the scene for the next frame at the current stacking context.
3099    /// Quads are colored rectangular regions with an optional background, border, and corner radius.
3100    /// see [`fill`], [`outline`], and [`quad`] to construct this type.
3101    ///
3102    /// This method should only be called as part of the paint phase of element drawing.
3103    ///
3104    /// Note that the `quad.corner_radii` are allowed to exceed the bounds, creating sharp corners
3105    /// where the circular arcs meet. This will not display well when combined with dashed borders.
3106    /// Use `Corners::clamp_radii_for_quad_size` if the radii should fit within the bounds.
3107    pub fn paint_quad(&mut self, quad: PaintQuad) {
3108        self.invalidator.debug_assert_paint();
3109
3110        let scale_factor = self.scale_factor();
3111        let content_mask = self.content_mask();
3112        let opacity = self.element_opacity();
3113        self.next_frame.scene.insert_primitive(Quad {
3114            order: 0,
3115            bounds: quad.bounds.scale(scale_factor),
3116            content_mask: content_mask.scale(scale_factor),
3117            background: quad.background.opacity(opacity),
3118            border_color: quad.border_color.opacity(opacity),
3119            corner_radii: quad.corner_radii.scale(scale_factor),
3120            border_widths: quad.border_widths.scale(scale_factor),
3121            border_style: quad.border_style,
3122        });
3123    }
3124
3125    /// Paint the given `Path` into the scene for the next frame at the current z-index.
3126    ///
3127    /// This method should only be called as part of the paint phase of element drawing.
3128    pub fn paint_path(&mut self, mut path: Path<Pixels>, color: impl Into<Background>) {
3129        self.invalidator.debug_assert_paint();
3130
3131        let scale_factor = self.scale_factor();
3132        let content_mask = self.content_mask();
3133        let opacity = self.element_opacity();
3134        path.content_mask = content_mask;
3135        let color: Background = color.into();
3136        path.color = color.opacity(opacity);
3137        self.next_frame
3138            .scene
3139            .insert_primitive(path.scale(scale_factor));
3140    }
3141
3142    /// Paint an underline into the scene for the next frame at the current z-index.
3143    ///
3144    /// This method should only be called as part of the paint phase of element drawing.
3145    pub fn paint_underline(
3146        &mut self,
3147        origin: Point<Pixels>,
3148        width: Pixels,
3149        style: &UnderlineStyle,
3150    ) {
3151        self.invalidator.debug_assert_paint();
3152
3153        let scale_factor = self.scale_factor();
3154        let height = if style.wavy {
3155            style.thickness * 3.
3156        } else {
3157            style.thickness
3158        };
3159        let bounds = Bounds {
3160            origin,
3161            size: size(width, height),
3162        };
3163        let content_mask = self.content_mask();
3164        let element_opacity = self.element_opacity();
3165
3166        self.next_frame.scene.insert_primitive(Underline {
3167            order: 0,
3168            pad: 0,
3169            bounds: bounds.scale(scale_factor),
3170            content_mask: content_mask.scale(scale_factor),
3171            color: style.color.unwrap_or_default().opacity(element_opacity),
3172            thickness: style.thickness.scale(scale_factor),
3173            wavy: if style.wavy { 1 } else { 0 },
3174        });
3175    }
3176
3177    /// Paint a strikethrough into the scene for the next frame at the current z-index.
3178    ///
3179    /// This method should only be called as part of the paint phase of element drawing.
3180    pub fn paint_strikethrough(
3181        &mut self,
3182        origin: Point<Pixels>,
3183        width: Pixels,
3184        style: &StrikethroughStyle,
3185    ) {
3186        self.invalidator.debug_assert_paint();
3187
3188        let scale_factor = self.scale_factor();
3189        let height = style.thickness;
3190        let bounds = Bounds {
3191            origin,
3192            size: size(width, height),
3193        };
3194        let content_mask = self.content_mask();
3195        let opacity = self.element_opacity();
3196
3197        self.next_frame.scene.insert_primitive(Underline {
3198            order: 0,
3199            pad: 0,
3200            bounds: bounds.scale(scale_factor),
3201            content_mask: content_mask.scale(scale_factor),
3202            thickness: style.thickness.scale(scale_factor),
3203            color: style.color.unwrap_or_default().opacity(opacity),
3204            wavy: 0,
3205        });
3206    }
3207
3208    /// Paints a monochrome (non-emoji) glyph into the scene for the next frame at the current z-index.
3209    ///
3210    /// The y component of the origin is the baseline of the glyph.
3211    /// You should generally prefer to use the [`ShapedLine::paint`](crate::ShapedLine::paint) or
3212    /// [`WrappedLine::paint`](crate::WrappedLine::paint) methods in the [`TextSystem`](crate::TextSystem).
3213    /// This method is only useful if you need to paint a single glyph that has already been shaped.
3214    ///
3215    /// This method should only be called as part of the paint phase of element drawing.
3216    pub fn paint_glyph(
3217        &mut self,
3218        origin: Point<Pixels>,
3219        font_id: FontId,
3220        glyph_id: GlyphId,
3221        font_size: Pixels,
3222        color: Hsla,
3223    ) -> Result<()> {
3224        self.invalidator.debug_assert_paint();
3225
3226        let element_opacity = self.element_opacity();
3227        let scale_factor = self.scale_factor();
3228        let glyph_origin = origin.scale(scale_factor);
3229
3230        let subpixel_variant = Point {
3231            x: (glyph_origin.x.0.fract() * SUBPIXEL_VARIANTS_X as f32).floor() as u8,
3232            y: (glyph_origin.y.0.fract() * SUBPIXEL_VARIANTS_Y as f32).floor() as u8,
3233        };
3234        let subpixel_rendering = self.should_use_subpixel_rendering(font_id, font_size);
3235        let params = RenderGlyphParams {
3236            font_id,
3237            glyph_id,
3238            font_size,
3239            subpixel_variant,
3240            scale_factor,
3241            is_emoji: false,
3242            subpixel_rendering,
3243        };
3244
3245        let raster_bounds = self.text_system().raster_bounds(&params)?;
3246        if !raster_bounds.is_zero() {
3247            let tile = self
3248                .sprite_atlas
3249                .get_or_insert_with(&params.clone().into(), &mut || {
3250                    let (size, bytes) = self.text_system().rasterize_glyph(&params)?;
3251                    Ok(Some((size, Cow::Owned(bytes))))
3252                })?
3253                .expect("Callback above only errors or returns Some");
3254            let bounds = Bounds {
3255                origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
3256                size: tile.bounds.size.map(Into::into),
3257            };
3258            let content_mask = self.content_mask().scale(scale_factor);
3259
3260            if subpixel_rendering {
3261                self.next_frame.scene.insert_primitive(SubpixelSprite {
3262                    order: 0,
3263                    pad: 0,
3264                    bounds,
3265                    content_mask,
3266                    color: color.opacity(element_opacity),
3267                    tile,
3268                    transformation: TransformationMatrix::unit(),
3269                });
3270            } else {
3271                self.next_frame.scene.insert_primitive(MonochromeSprite {
3272                    order: 0,
3273                    pad: 0,
3274                    bounds,
3275                    content_mask,
3276                    color: color.opacity(element_opacity),
3277                    tile,
3278                    transformation: TransformationMatrix::unit(),
3279                });
3280            }
3281        }
3282        Ok(())
3283    }
3284
3285    fn should_use_subpixel_rendering(&self, font_id: FontId, font_size: Pixels) -> bool {
3286        if self.platform_window.background_appearance() != WindowBackgroundAppearance::Opaque {
3287            return false;
3288        }
3289
3290        if !self.platform_window.is_subpixel_rendering_supported() {
3291            return false;
3292        }
3293
3294        let mode = match self.text_rendering_mode.get() {
3295            TextRenderingMode::PlatformDefault => self
3296                .text_system()
3297                .recommended_rendering_mode(font_id, font_size),
3298            mode => mode,
3299        };
3300
3301        mode == TextRenderingMode::Subpixel
3302    }
3303
3304    /// Paints an emoji glyph into the scene for the next frame at the current z-index.
3305    ///
3306    /// The y component of the origin is the baseline of the glyph.
3307    /// You should generally prefer to use the [`ShapedLine::paint`](crate::ShapedLine::paint) or
3308    /// [`WrappedLine::paint`](crate::WrappedLine::paint) methods in the [`TextSystem`](crate::TextSystem).
3309    /// This method is only useful if you need to paint a single emoji that has already been shaped.
3310    ///
3311    /// This method should only be called as part of the paint phase of element drawing.
3312    pub fn paint_emoji(
3313        &mut self,
3314        origin: Point<Pixels>,
3315        font_id: FontId,
3316        glyph_id: GlyphId,
3317        font_size: Pixels,
3318    ) -> Result<()> {
3319        self.invalidator.debug_assert_paint();
3320
3321        let scale_factor = self.scale_factor();
3322        let glyph_origin = origin.scale(scale_factor);
3323        let params = RenderGlyphParams {
3324            font_id,
3325            glyph_id,
3326            font_size,
3327            // We don't render emojis with subpixel variants.
3328            subpixel_variant: Default::default(),
3329            scale_factor,
3330            is_emoji: true,
3331            subpixel_rendering: false,
3332        };
3333
3334        let raster_bounds = self.text_system().raster_bounds(&params)?;
3335        if !raster_bounds.is_zero() {
3336            let tile = self
3337                .sprite_atlas
3338                .get_or_insert_with(&params.clone().into(), &mut || {
3339                    let (size, bytes) = self.text_system().rasterize_glyph(&params)?;
3340                    Ok(Some((size, Cow::Owned(bytes))))
3341                })?
3342                .expect("Callback above only errors or returns Some");
3343
3344            let bounds = Bounds {
3345                origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
3346                size: tile.bounds.size.map(Into::into),
3347            };
3348            let content_mask = self.content_mask().scale(scale_factor);
3349            let opacity = self.element_opacity();
3350
3351            self.next_frame.scene.insert_primitive(PolychromeSprite {
3352                order: 0,
3353                pad: 0,
3354                grayscale: false,
3355                bounds,
3356                corner_radii: Default::default(),
3357                content_mask,
3358                tile,
3359                opacity,
3360            });
3361        }
3362        Ok(())
3363    }
3364
3365    /// Paint a monochrome SVG into the scene for the next frame at the current stacking context.
3366    ///
3367    /// This method should only be called as part of the paint phase of element drawing.
3368    pub fn paint_svg(
3369        &mut self,
3370        bounds: Bounds<Pixels>,
3371        path: SharedString,
3372        mut data: Option<&[u8]>,
3373        transformation: TransformationMatrix,
3374        color: Hsla,
3375        cx: &App,
3376    ) -> Result<()> {
3377        self.invalidator.debug_assert_paint();
3378
3379        let element_opacity = self.element_opacity();
3380        let scale_factor = self.scale_factor();
3381
3382        let bounds = bounds.scale(scale_factor);
3383        let params = RenderSvgParams {
3384            path,
3385            size: bounds.size.map(|pixels| {
3386                DevicePixels::from((pixels.0 * SMOOTH_SVG_SCALE_FACTOR).ceil() as i32)
3387            }),
3388        };
3389
3390        let Some(tile) =
3391            self.sprite_atlas
3392                .get_or_insert_with(&params.clone().into(), &mut || {
3393                    let Some((size, bytes)) = cx.svg_renderer.render_alpha_mask(&params, data)?
3394                    else {
3395                        return Ok(None);
3396                    };
3397                    Ok(Some((size, Cow::Owned(bytes))))
3398                })?
3399        else {
3400            return Ok(());
3401        };
3402        let content_mask = self.content_mask().scale(scale_factor);
3403        let svg_bounds = Bounds {
3404            origin: bounds.center()
3405                - Point::new(
3406                    ScaledPixels(tile.bounds.size.width.0 as f32 / SMOOTH_SVG_SCALE_FACTOR / 2.),
3407                    ScaledPixels(tile.bounds.size.height.0 as f32 / SMOOTH_SVG_SCALE_FACTOR / 2.),
3408                ),
3409            size: tile
3410                .bounds
3411                .size
3412                .map(|value| ScaledPixels(value.0 as f32 / SMOOTH_SVG_SCALE_FACTOR)),
3413        };
3414
3415        self.next_frame.scene.insert_primitive(MonochromeSprite {
3416            order: 0,
3417            pad: 0,
3418            bounds: svg_bounds
3419                .map_origin(|origin| origin.round())
3420                .map_size(|size| size.ceil()),
3421            content_mask,
3422            color: color.opacity(element_opacity),
3423            tile,
3424            transformation,
3425        });
3426
3427        Ok(())
3428    }
3429
3430    /// Paint an image into the scene for the next frame at the current z-index.
3431    /// This method will panic if the frame_index is not valid
3432    ///
3433    /// This method should only be called as part of the paint phase of element drawing.
3434    pub fn paint_image(
3435        &mut self,
3436        bounds: Bounds<Pixels>,
3437        corner_radii: Corners<Pixels>,
3438        data: Arc<RenderImage>,
3439        frame_index: usize,
3440        grayscale: bool,
3441    ) -> Result<()> {
3442        self.invalidator.debug_assert_paint();
3443
3444        let scale_factor = self.scale_factor();
3445        let bounds = bounds.scale(scale_factor);
3446        let params = RenderImageParams {
3447            image_id: data.id,
3448            frame_index,
3449        };
3450
3451        let tile = self
3452            .sprite_atlas
3453            .get_or_insert_with(&params.into(), &mut || {
3454                Ok(Some((
3455                    data.size(frame_index),
3456                    Cow::Borrowed(
3457                        data.as_bytes(frame_index)
3458                            .expect("It's the caller's job to pass a valid frame index"),
3459                    ),
3460                )))
3461            })?
3462            .expect("Callback above only returns Some");
3463        let content_mask = self.content_mask().scale(scale_factor);
3464        let corner_radii = corner_radii.scale(scale_factor);
3465        let opacity = self.element_opacity();
3466
3467        self.next_frame.scene.insert_primitive(PolychromeSprite {
3468            order: 0,
3469            pad: 0,
3470            grayscale,
3471            bounds: bounds
3472                .map_origin(|origin| origin.floor())
3473                .map_size(|size| size.ceil()),
3474            content_mask,
3475            corner_radii,
3476            tile,
3477            opacity,
3478        });
3479        Ok(())
3480    }
3481
3482    /// Paint a surface into the scene for the next frame at the current z-index.
3483    ///
3484    /// This method should only be called as part of the paint phase of element drawing.
3485    #[cfg(target_os = "macos")]
3486    pub fn paint_surface(&mut self, bounds: Bounds<Pixels>, image_buffer: CVPixelBuffer) {
3487        use crate::PaintSurface;
3488
3489        self.invalidator.debug_assert_paint();
3490
3491        let scale_factor = self.scale_factor();
3492        let bounds = bounds.scale(scale_factor);
3493        let content_mask = self.content_mask().scale(scale_factor);
3494        self.next_frame.scene.insert_primitive(PaintSurface {
3495            order: 0,
3496            bounds,
3497            content_mask,
3498            image_buffer,
3499        });
3500    }
3501
3502    /// Removes an image from the sprite atlas.
3503    pub fn drop_image(&mut self, data: Arc<RenderImage>) -> Result<()> {
3504        for frame_index in 0..data.frame_count() {
3505            let params = RenderImageParams {
3506                image_id: data.id,
3507                frame_index,
3508            };
3509
3510            self.sprite_atlas.remove(&params.clone().into());
3511        }
3512
3513        Ok(())
3514    }
3515
3516    /// Add a node to the layout tree for the current frame. Takes the `Style` of the element for which
3517    /// layout is being requested, along with the layout ids of any children. This method is called during
3518    /// calls to the [`Element::request_layout`] trait method and enables any element to participate in layout.
3519    ///
3520    /// This method should only be called as part of the request_layout or prepaint phase of element drawing.
3521    #[must_use]
3522    pub fn request_layout(
3523        &mut self,
3524        style: Style,
3525        children: impl IntoIterator<Item = LayoutId>,
3526        cx: &mut App,
3527    ) -> LayoutId {
3528        self.invalidator.debug_assert_prepaint();
3529
3530        cx.layout_id_buffer.clear();
3531        cx.layout_id_buffer.extend(children);
3532        let rem_size = self.rem_size();
3533        let scale_factor = self.scale_factor();
3534
3535        self.layout_engine.as_mut().unwrap().request_layout(
3536            style,
3537            rem_size,
3538            scale_factor,
3539            &cx.layout_id_buffer,
3540        )
3541    }
3542
3543    /// Add a node to the layout tree for the current frame. Instead of taking a `Style` and children,
3544    /// this variant takes a function that is invoked during layout so you can use arbitrary logic to
3545    /// determine the element's size. One place this is used internally is when measuring text.
3546    ///
3547    /// The given closure is invoked at layout time with the known dimensions and available space and
3548    /// returns a `Size`.
3549    ///
3550    /// This method should only be called as part of the request_layout or prepaint phase of element drawing.
3551    pub fn request_measured_layout<F>(&mut self, style: Style, measure: F) -> LayoutId
3552    where
3553        F: Fn(Size<Option<Pixels>>, Size<AvailableSpace>, &mut Window, &mut App) -> Size<Pixels>
3554            + 'static,
3555    {
3556        self.invalidator.debug_assert_prepaint();
3557
3558        let rem_size = self.rem_size();
3559        let scale_factor = self.scale_factor();
3560        self.layout_engine
3561            .as_mut()
3562            .unwrap()
3563            .request_measured_layout(style, rem_size, scale_factor, measure)
3564    }
3565
3566    /// Compute the layout for the given id within the given available space.
3567    /// This method is called for its side effect, typically by the framework prior to painting.
3568    /// After calling it, you can request the bounds of the given layout node id or any descendant.
3569    ///
3570    /// This method should only be called as part of the prepaint phase of element drawing.
3571    pub fn compute_layout(
3572        &mut self,
3573        layout_id: LayoutId,
3574        available_space: Size<AvailableSpace>,
3575        cx: &mut App,
3576    ) {
3577        self.invalidator.debug_assert_prepaint();
3578
3579        let mut layout_engine = self.layout_engine.take().unwrap();
3580        layout_engine.compute_layout(layout_id, available_space, self, cx);
3581        self.layout_engine = Some(layout_engine);
3582    }
3583
3584    /// Obtain the bounds computed for the given LayoutId relative to the window. This method will usually be invoked by
3585    /// GPUI itself automatically in order to pass your element its `Bounds` automatically.
3586    ///
3587    /// This method should only be called as part of element drawing.
3588    pub fn layout_bounds(&mut self, layout_id: LayoutId) -> Bounds<Pixels> {
3589        self.invalidator.debug_assert_prepaint();
3590
3591        let scale_factor = self.scale_factor();
3592        let mut bounds = self
3593            .layout_engine
3594            .as_mut()
3595            .unwrap()
3596            .layout_bounds(layout_id, scale_factor)
3597            .map(Into::into);
3598        bounds.origin += self.element_offset();
3599        bounds
3600    }
3601
3602    /// This method should be called during `prepaint`. You can use
3603    /// the returned [Hitbox] during `paint` or in an event handler
3604    /// to determine whether the inserted hitbox was the topmost.
3605    ///
3606    /// This method should only be called as part of the prepaint phase of element drawing.
3607    pub fn insert_hitbox(&mut self, bounds: Bounds<Pixels>, behavior: HitboxBehavior) -> Hitbox {
3608        self.invalidator.debug_assert_prepaint();
3609
3610        let content_mask = self.content_mask();
3611        let mut id = self.next_hitbox_id;
3612        self.next_hitbox_id = self.next_hitbox_id.next();
3613        let hitbox = Hitbox {
3614            id,
3615            bounds,
3616            content_mask,
3617            behavior,
3618        };
3619        self.next_frame.hitboxes.push(hitbox.clone());
3620        hitbox
3621    }
3622
3623    /// Set a hitbox which will act as a control area of the platform window.
3624    ///
3625    /// This method should only be called as part of the paint phase of element drawing.
3626    pub fn insert_window_control_hitbox(&mut self, area: WindowControlArea, hitbox: Hitbox) {
3627        self.invalidator.debug_assert_paint();
3628        self.next_frame.window_control_hitboxes.push((area, hitbox));
3629    }
3630
3631    /// Sets the key context for the current element. This context will be used to translate
3632    /// keybindings into actions.
3633    ///
3634    /// This method should only be called as part of the paint phase of element drawing.
3635    pub fn set_key_context(&mut self, context: KeyContext) {
3636        self.invalidator.debug_assert_paint();
3637        self.next_frame.dispatch_tree.set_key_context(context);
3638    }
3639
3640    /// Sets the focus handle for the current element. This handle will be used to manage focus state
3641    /// and keyboard event dispatch for the element.
3642    ///
3643    /// This method should only be called as part of the prepaint phase of element drawing.
3644    pub fn set_focus_handle(&mut self, focus_handle: &FocusHandle, _: &App) {
3645        self.invalidator.debug_assert_prepaint();
3646        if focus_handle.is_focused(self) {
3647            self.next_frame.focus = Some(focus_handle.id);
3648        }
3649        self.next_frame.dispatch_tree.set_focus_id(focus_handle.id);
3650    }
3651
3652    /// Sets the view id for the current element, which will be used to manage view caching.
3653    ///
3654    /// This method should only be called as part of element prepaint. We plan on removing this
3655    /// method eventually when we solve some issues that require us to construct editor elements
3656    /// directly instead of always using editors via views.
3657    pub fn set_view_id(&mut self, view_id: EntityId) {
3658        self.invalidator.debug_assert_prepaint();
3659        self.next_frame.dispatch_tree.set_view_id(view_id);
3660    }
3661
3662    /// Get the entity ID for the currently rendering view
3663    pub fn current_view(&self) -> EntityId {
3664        self.invalidator.debug_assert_paint_or_prepaint();
3665        self.rendered_entity_stack.last().copied().unwrap()
3666    }
3667
3668    #[inline]
3669    pub(crate) fn with_rendered_view<R>(
3670        &mut self,
3671        id: EntityId,
3672        f: impl FnOnce(&mut Self) -> R,
3673    ) -> R {
3674        self.rendered_entity_stack.push(id);
3675        let result = f(self);
3676        self.rendered_entity_stack.pop();
3677        result
3678    }
3679
3680    /// Executes the provided function with the specified image cache.
3681    pub fn with_image_cache<F, R>(&mut self, image_cache: Option<AnyImageCache>, f: F) -> R
3682    where
3683        F: FnOnce(&mut Self) -> R,
3684    {
3685        if let Some(image_cache) = image_cache {
3686            self.image_cache_stack.push(image_cache);
3687            let result = f(self);
3688            self.image_cache_stack.pop();
3689            result
3690        } else {
3691            f(self)
3692        }
3693    }
3694
3695    /// Sets an input handler, such as [`ElementInputHandler`][element_input_handler], which interfaces with the
3696    /// platform to receive textual input with proper integration with concerns such
3697    /// as IME interactions. This handler will be active for the upcoming frame until the following frame is
3698    /// rendered.
3699    ///
3700    /// This method should only be called as part of the paint phase of element drawing.
3701    ///
3702    /// [element_input_handler]: crate::ElementInputHandler
3703    pub fn handle_input(
3704        &mut self,
3705        focus_handle: &FocusHandle,
3706        input_handler: impl InputHandler,
3707        cx: &App,
3708    ) {
3709        self.invalidator.debug_assert_paint();
3710
3711        if focus_handle.is_focused(self) {
3712            let cx = self.to_async(cx);
3713            self.next_frame
3714                .input_handlers
3715                .push(Some(PlatformInputHandler::new(cx, Box::new(input_handler))));
3716        }
3717    }
3718
3719    /// Register a mouse event listener on the window for the next frame. The type of event
3720    /// is determined by the first parameter of the given listener. When the next frame is rendered
3721    /// the listener will be cleared.
3722    ///
3723    /// This method should only be called as part of the paint phase of element drawing.
3724    pub fn on_mouse_event<Event: MouseEvent>(
3725        &mut self,
3726        mut listener: impl FnMut(&Event, DispatchPhase, &mut Window, &mut App) + 'static,
3727    ) {
3728        self.invalidator.debug_assert_paint();
3729
3730        self.next_frame.mouse_listeners.push(Some(Box::new(
3731            move |event: &dyn Any, phase: DispatchPhase, window: &mut Window, cx: &mut App| {
3732                if let Some(event) = event.downcast_ref() {
3733                    listener(event, phase, window, cx)
3734                }
3735            },
3736        )));
3737    }
3738
3739    /// Register a key event listener on this node for the next frame. The type of event
3740    /// is determined by the first parameter of the given listener. When the next frame is rendered
3741    /// the listener will be cleared.
3742    ///
3743    /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
3744    /// a specific need to register a listener yourself.
3745    ///
3746    /// This method should only be called as part of the paint phase of element drawing.
3747    pub fn on_key_event<Event: KeyEvent>(
3748        &mut self,
3749        listener: impl Fn(&Event, DispatchPhase, &mut Window, &mut App) + 'static,
3750    ) {
3751        self.invalidator.debug_assert_paint();
3752
3753        self.next_frame.dispatch_tree.on_key_event(Rc::new(
3754            move |event: &dyn Any, phase, window: &mut Window, cx: &mut App| {
3755                if let Some(event) = event.downcast_ref::<Event>() {
3756                    listener(event, phase, window, cx)
3757                }
3758            },
3759        ));
3760    }
3761
3762    /// Register a modifiers changed event listener on the window for the next frame.
3763    ///
3764    /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
3765    /// a specific need to register a global listener.
3766    ///
3767    /// This method should only be called as part of the paint phase of element drawing.
3768    pub fn on_modifiers_changed(
3769        &mut self,
3770        listener: impl Fn(&ModifiersChangedEvent, &mut Window, &mut App) + 'static,
3771    ) {
3772        self.invalidator.debug_assert_paint();
3773
3774        self.next_frame.dispatch_tree.on_modifiers_changed(Rc::new(
3775            move |event: &ModifiersChangedEvent, window: &mut Window, cx: &mut App| {
3776                listener(event, window, cx)
3777            },
3778        ));
3779    }
3780
3781    /// Register a listener to be called when the given focus handle or one of its descendants receives focus.
3782    /// This does not fire if the given focus handle - or one of its descendants - was previously focused.
3783    /// Returns a subscription and persists until the subscription is dropped.
3784    pub fn on_focus_in(
3785        &mut self,
3786        handle: &FocusHandle,
3787        cx: &mut App,
3788        mut listener: impl FnMut(&mut Window, &mut App) + 'static,
3789    ) -> Subscription {
3790        let focus_id = handle.id;
3791        let (subscription, activate) =
3792            self.new_focus_listener(Box::new(move |event, window, cx| {
3793                if event.is_focus_in(focus_id) {
3794                    listener(window, cx);
3795                }
3796                true
3797            }));
3798        cx.defer(move |_| activate());
3799        subscription
3800    }
3801
3802    /// Register a listener to be called when the given focus handle or one of its descendants loses focus.
3803    /// Returns a subscription and persists until the subscription is dropped.
3804    pub fn on_focus_out(
3805        &mut self,
3806        handle: &FocusHandle,
3807        cx: &mut App,
3808        mut listener: impl FnMut(FocusOutEvent, &mut Window, &mut App) + 'static,
3809    ) -> Subscription {
3810        let focus_id = handle.id;
3811        let (subscription, activate) =
3812            self.new_focus_listener(Box::new(move |event, window, cx| {
3813                if let Some(blurred_id) = event.previous_focus_path.last().copied()
3814                    && event.is_focus_out(focus_id)
3815                {
3816                    let event = FocusOutEvent {
3817                        blurred: WeakFocusHandle {
3818                            id: blurred_id,
3819                            handles: Arc::downgrade(&cx.focus_handles),
3820                        },
3821                    };
3822                    listener(event, window, cx)
3823                }
3824                true
3825            }));
3826        cx.defer(move |_| activate());
3827        subscription
3828    }
3829
3830    fn reset_cursor_style(&self, cx: &mut App) {
3831        // Set the cursor only if we're the active window.
3832        if self.is_window_hovered() {
3833            let style = self
3834                .rendered_frame
3835                .cursor_style(self)
3836                .unwrap_or(CursorStyle::Arrow);
3837            cx.platform.set_cursor_style(style);
3838        }
3839    }
3840
3841    /// Dispatch a given keystroke as though the user had typed it.
3842    /// You can create a keystroke with Keystroke::parse("").
3843    pub fn dispatch_keystroke(&mut self, keystroke: Keystroke, cx: &mut App) -> bool {
3844        let keystroke = keystroke.with_simulated_ime();
3845        let result = self.dispatch_event(
3846            PlatformInput::KeyDown(KeyDownEvent {
3847                keystroke: keystroke.clone(),
3848                is_held: false,
3849                prefer_character_input: false,
3850            }),
3851            cx,
3852        );
3853        if !result.propagate {
3854            return true;
3855        }
3856
3857        if let Some(input) = keystroke.key_char
3858            && let Some(mut input_handler) = self.platform_window.take_input_handler()
3859        {
3860            input_handler.dispatch_input(&input, self, cx);
3861            self.platform_window.set_input_handler(input_handler);
3862            return true;
3863        }
3864
3865        false
3866    }
3867
3868    /// Return a key binding string for an action, to display in the UI. Uses the highest precedence
3869    /// binding for the action (last binding added to the keymap).
3870    pub fn keystroke_text_for(&self, action: &dyn Action) -> String {
3871        self.highest_precedence_binding_for_action(action)
3872            .map(|binding| {
3873                binding
3874                    .keystrokes()
3875                    .iter()
3876                    .map(ToString::to_string)
3877                    .collect::<Vec<_>>()
3878                    .join(" ")
3879            })
3880            .unwrap_or_else(|| action.name().to_string())
3881    }
3882
3883    /// Dispatch a mouse or keyboard event on the window.
3884    #[profiling::function]
3885    pub fn dispatch_event(&mut self, event: PlatformInput, cx: &mut App) -> DispatchEventResult {
3886        // Track whether this input was keyboard-based for focus-visible styling
3887        self.last_input_modality = match &event {
3888            PlatformInput::KeyDown(_) | PlatformInput::ModifiersChanged(_) => {
3889                InputModality::Keyboard
3890            }
3891            PlatformInput::MouseDown(e) if e.is_focusing() => InputModality::Mouse,
3892            _ => self.last_input_modality,
3893        };
3894
3895        // Handlers may set this to false by calling `stop_propagation`.
3896        cx.propagate_event = true;
3897        // Handlers may set this to true by calling `prevent_default`.
3898        self.default_prevented = false;
3899
3900        let event = match event {
3901            // Track the mouse position with our own state, since accessing the platform
3902            // API for the mouse position can only occur on the main thread.
3903            PlatformInput::MouseMove(mouse_move) => {
3904                self.mouse_position = mouse_move.position;
3905                self.modifiers = mouse_move.modifiers;
3906                PlatformInput::MouseMove(mouse_move)
3907            }
3908            PlatformInput::MouseDown(mouse_down) => {
3909                self.mouse_position = mouse_down.position;
3910                self.modifiers = mouse_down.modifiers;
3911                PlatformInput::MouseDown(mouse_down)
3912            }
3913            PlatformInput::MouseUp(mouse_up) => {
3914                self.mouse_position = mouse_up.position;
3915                self.modifiers = mouse_up.modifiers;
3916                PlatformInput::MouseUp(mouse_up)
3917            }
3918            PlatformInput::MousePressure(mouse_pressure) => {
3919                PlatformInput::MousePressure(mouse_pressure)
3920            }
3921            PlatformInput::MouseExited(mouse_exited) => {
3922                self.modifiers = mouse_exited.modifiers;
3923                PlatformInput::MouseExited(mouse_exited)
3924            }
3925            PlatformInput::ModifiersChanged(modifiers_changed) => {
3926                self.modifiers = modifiers_changed.modifiers;
3927                self.capslock = modifiers_changed.capslock;
3928                PlatformInput::ModifiersChanged(modifiers_changed)
3929            }
3930            PlatformInput::ScrollWheel(scroll_wheel) => {
3931                self.mouse_position = scroll_wheel.position;
3932                self.modifiers = scroll_wheel.modifiers;
3933                PlatformInput::ScrollWheel(scroll_wheel)
3934            }
3935            // Translate dragging and dropping of external files from the operating system
3936            // to internal drag and drop events.
3937            PlatformInput::FileDrop(file_drop) => match file_drop {
3938                FileDropEvent::Entered { position, paths } => {
3939                    self.mouse_position = position;
3940                    if cx.active_drag.is_none() {
3941                        cx.active_drag = Some(AnyDrag {
3942                            value: Arc::new(paths.clone()),
3943                            view: cx.new(|_| paths).into(),
3944                            cursor_offset: position,
3945                            cursor_style: None,
3946                        });
3947                    }
3948                    PlatformInput::MouseMove(MouseMoveEvent {
3949                        position,
3950                        pressed_button: Some(MouseButton::Left),
3951                        modifiers: Modifiers::default(),
3952                    })
3953                }
3954                FileDropEvent::Pending { position } => {
3955                    self.mouse_position = position;
3956                    PlatformInput::MouseMove(MouseMoveEvent {
3957                        position,
3958                        pressed_button: Some(MouseButton::Left),
3959                        modifiers: Modifiers::default(),
3960                    })
3961                }
3962                FileDropEvent::Submit { position } => {
3963                    cx.activate(true);
3964                    self.mouse_position = position;
3965                    PlatformInput::MouseUp(MouseUpEvent {
3966                        button: MouseButton::Left,
3967                        position,
3968                        modifiers: Modifiers::default(),
3969                        click_count: 1,
3970                    })
3971                }
3972                FileDropEvent::Exited => {
3973                    cx.active_drag.take();
3974                    PlatformInput::FileDrop(FileDropEvent::Exited)
3975                }
3976            },
3977            PlatformInput::KeyDown(_) | PlatformInput::KeyUp(_) => event,
3978        };
3979
3980        if let Some(any_mouse_event) = event.mouse_event() {
3981            self.dispatch_mouse_event(any_mouse_event, cx);
3982        } else if let Some(any_key_event) = event.keyboard_event() {
3983            self.dispatch_key_event(any_key_event, cx);
3984        }
3985
3986        if self.invalidator.is_dirty() {
3987            self.input_rate_tracker.borrow_mut().record_input();
3988        }
3989
3990        DispatchEventResult {
3991            propagate: cx.propagate_event,
3992            default_prevented: self.default_prevented,
3993        }
3994    }
3995
3996    fn dispatch_mouse_event(&mut self, event: &dyn Any, cx: &mut App) {
3997        let hit_test = self.rendered_frame.hit_test(self.mouse_position());
3998        if hit_test != self.mouse_hit_test {
3999            self.mouse_hit_test = hit_test;
4000            self.reset_cursor_style(cx);
4001        }
4002
4003        #[cfg(any(feature = "inspector", debug_assertions))]
4004        if self.is_inspector_picking(cx) {
4005            self.handle_inspector_mouse_event(event, cx);
4006            // When inspector is picking, all other mouse handling is skipped.
4007            return;
4008        }
4009
4010        let mut mouse_listeners = mem::take(&mut self.rendered_frame.mouse_listeners);
4011
4012        // Capture phase, events bubble from back to front. Handlers for this phase are used for
4013        // special purposes, such as detecting events outside of a given Bounds.
4014        for listener in &mut mouse_listeners {
4015            let listener = listener.as_mut().unwrap();
4016            listener(event, DispatchPhase::Capture, self, cx);
4017            if !cx.propagate_event {
4018                break;
4019            }
4020        }
4021
4022        // Bubble phase, where most normal handlers do their work.
4023        if cx.propagate_event {
4024            for listener in mouse_listeners.iter_mut().rev() {
4025                let listener = listener.as_mut().unwrap();
4026                listener(event, DispatchPhase::Bubble, self, cx);
4027                if !cx.propagate_event {
4028                    break;
4029                }
4030            }
4031        }
4032
4033        self.rendered_frame.mouse_listeners = mouse_listeners;
4034
4035        if cx.has_active_drag() {
4036            if event.is::<MouseMoveEvent>() {
4037                // If this was a mouse move event, redraw the window so that the
4038                // active drag can follow the mouse cursor.
4039                self.refresh();
4040            } else if event.is::<MouseUpEvent>() {
4041                // If this was a mouse up event, cancel the active drag and redraw
4042                // the window.
4043                cx.active_drag = None;
4044                self.refresh();
4045            }
4046        }
4047    }
4048
4049    fn dispatch_key_event(&mut self, event: &dyn Any, cx: &mut App) {
4050        if self.invalidator.is_dirty() {
4051            self.draw(cx).clear();
4052        }
4053
4054        let node_id = self.focus_node_id_in_rendered_frame(self.focus);
4055        let dispatch_path = self.rendered_frame.dispatch_tree.dispatch_path(node_id);
4056
4057        let mut keystroke: Option<Keystroke> = None;
4058
4059        if let Some(event) = event.downcast_ref::<ModifiersChangedEvent>() {
4060            if event.modifiers.number_of_modifiers() == 0
4061                && self.pending_modifier.modifiers.number_of_modifiers() == 1
4062                && !self.pending_modifier.saw_keystroke
4063            {
4064                let key = match self.pending_modifier.modifiers {
4065                    modifiers if modifiers.shift => Some("shift"),
4066                    modifiers if modifiers.control => Some("control"),
4067                    modifiers if modifiers.alt => Some("alt"),
4068                    modifiers if modifiers.platform => Some("platform"),
4069                    modifiers if modifiers.function => Some("function"),
4070                    _ => None,
4071                };
4072                if let Some(key) = key {
4073                    keystroke = Some(Keystroke {
4074                        key: key.to_string(),
4075                        key_char: None,
4076                        modifiers: Modifiers::default(),
4077                    });
4078                }
4079            }
4080
4081            if self.pending_modifier.modifiers.number_of_modifiers() == 0
4082                && event.modifiers.number_of_modifiers() == 1
4083            {
4084                self.pending_modifier.saw_keystroke = false
4085            }
4086            self.pending_modifier.modifiers = event.modifiers
4087        } else if let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() {
4088            self.pending_modifier.saw_keystroke = true;
4089            keystroke = Some(key_down_event.keystroke.clone());
4090        }
4091
4092        let Some(keystroke) = keystroke else {
4093            self.finish_dispatch_key_event(event, dispatch_path, self.context_stack(), cx);
4094            return;
4095        };
4096
4097        cx.propagate_event = true;
4098        self.dispatch_keystroke_interceptors(event, self.context_stack(), cx);
4099        if !cx.propagate_event {
4100            self.finish_dispatch_key_event(event, dispatch_path, self.context_stack(), cx);
4101            return;
4102        }
4103
4104        let mut currently_pending = self.pending_input.take().unwrap_or_default();
4105        if currently_pending.focus.is_some() && currently_pending.focus != self.focus {
4106            currently_pending = PendingInput::default();
4107        }
4108
4109        let match_result = self.rendered_frame.dispatch_tree.dispatch_key(
4110            currently_pending.keystrokes,
4111            keystroke,
4112            &dispatch_path,
4113        );
4114
4115        if !match_result.to_replay.is_empty() {
4116            self.replay_pending_input(match_result.to_replay, cx);
4117            cx.propagate_event = true;
4118        }
4119
4120        if !match_result.pending.is_empty() {
4121            currently_pending.timer.take();
4122            currently_pending.keystrokes = match_result.pending;
4123            currently_pending.focus = self.focus;
4124
4125            let text_input_requires_timeout = event
4126                .downcast_ref::<KeyDownEvent>()
4127                .filter(|key_down| key_down.keystroke.key_char.is_some())
4128                .and_then(|_| self.platform_window.take_input_handler())
4129                .map_or(false, |mut input_handler| {
4130                    let accepts = input_handler.accepts_text_input(self, cx);
4131                    self.platform_window.set_input_handler(input_handler);
4132                    accepts
4133                });
4134
4135            currently_pending.needs_timeout |=
4136                match_result.pending_has_binding || text_input_requires_timeout;
4137
4138            if currently_pending.needs_timeout {
4139                currently_pending.timer = Some(self.spawn(cx, async move |cx| {
4140                    cx.background_executor.timer(Duration::from_secs(1)).await;
4141                    cx.update(move |window, cx| {
4142                        let Some(currently_pending) = window
4143                            .pending_input
4144                            .take()
4145                            .filter(|pending| pending.focus == window.focus)
4146                        else {
4147                            return;
4148                        };
4149
4150                        let node_id = window.focus_node_id_in_rendered_frame(window.focus);
4151                        let dispatch_path =
4152                            window.rendered_frame.dispatch_tree.dispatch_path(node_id);
4153
4154                        let to_replay = window
4155                            .rendered_frame
4156                            .dispatch_tree
4157                            .flush_dispatch(currently_pending.keystrokes, &dispatch_path);
4158
4159                        window.pending_input_changed(cx);
4160                        window.replay_pending_input(to_replay, cx)
4161                    })
4162                    .log_err();
4163                }));
4164            } else {
4165                currently_pending.timer = None;
4166            }
4167            self.pending_input = Some(currently_pending);
4168            self.pending_input_changed(cx);
4169            cx.propagate_event = false;
4170            return;
4171        }
4172
4173        let skip_bindings = event
4174            .downcast_ref::<KeyDownEvent>()
4175            .filter(|key_down_event| key_down_event.prefer_character_input)
4176            .map(|_| {
4177                self.platform_window
4178                    .take_input_handler()
4179                    .map_or(false, |mut input_handler| {
4180                        let accepts = input_handler.accepts_text_input(self, cx);
4181                        self.platform_window.set_input_handler(input_handler);
4182                        // If modifiers are not excessive (e.g. AltGr), and the input handler is accepting text input,
4183                        // we prefer the text input over bindings.
4184                        accepts
4185                    })
4186            })
4187            .unwrap_or(false);
4188
4189        if !skip_bindings {
4190            for binding in match_result.bindings {
4191                self.dispatch_action_on_node(node_id, binding.action.as_ref(), cx);
4192                if !cx.propagate_event {
4193                    self.dispatch_keystroke_observers(
4194                        event,
4195                        Some(binding.action),
4196                        match_result.context_stack,
4197                        cx,
4198                    );
4199                    self.pending_input_changed(cx);
4200                    return;
4201                }
4202            }
4203        }
4204
4205        self.finish_dispatch_key_event(event, dispatch_path, match_result.context_stack, cx);
4206        self.pending_input_changed(cx);
4207    }
4208
4209    fn finish_dispatch_key_event(
4210        &mut self,
4211        event: &dyn Any,
4212        dispatch_path: SmallVec<[DispatchNodeId; 32]>,
4213        context_stack: Vec<KeyContext>,
4214        cx: &mut App,
4215    ) {
4216        self.dispatch_key_down_up_event(event, &dispatch_path, cx);
4217        if !cx.propagate_event {
4218            return;
4219        }
4220
4221        self.dispatch_modifiers_changed_event(event, &dispatch_path, cx);
4222        if !cx.propagate_event {
4223            return;
4224        }
4225
4226        self.dispatch_keystroke_observers(event, None, context_stack, cx);
4227    }
4228
4229    pub(crate) fn pending_input_changed(&mut self, cx: &mut App) {
4230        self.pending_input_observers
4231            .clone()
4232            .retain(&(), |callback| callback(self, cx));
4233    }
4234
4235    fn dispatch_key_down_up_event(
4236        &mut self,
4237        event: &dyn Any,
4238        dispatch_path: &SmallVec<[DispatchNodeId; 32]>,
4239        cx: &mut App,
4240    ) {
4241        // Capture phase
4242        for node_id in dispatch_path {
4243            let node = self.rendered_frame.dispatch_tree.node(*node_id);
4244
4245            for key_listener in node.key_listeners.clone() {
4246                key_listener(event, DispatchPhase::Capture, self, cx);
4247                if !cx.propagate_event {
4248                    return;
4249                }
4250            }
4251        }
4252
4253        // Bubble phase
4254        for node_id in dispatch_path.iter().rev() {
4255            // Handle low level key events
4256            let node = self.rendered_frame.dispatch_tree.node(*node_id);
4257            for key_listener in node.key_listeners.clone() {
4258                key_listener(event, DispatchPhase::Bubble, self, cx);
4259                if !cx.propagate_event {
4260                    return;
4261                }
4262            }
4263        }
4264    }
4265
4266    fn dispatch_modifiers_changed_event(
4267        &mut self,
4268        event: &dyn Any,
4269        dispatch_path: &SmallVec<[DispatchNodeId; 32]>,
4270        cx: &mut App,
4271    ) {
4272        let Some(event) = event.downcast_ref::<ModifiersChangedEvent>() else {
4273            return;
4274        };
4275        for node_id in dispatch_path.iter().rev() {
4276            let node = self.rendered_frame.dispatch_tree.node(*node_id);
4277            for listener in node.modifiers_changed_listeners.clone() {
4278                listener(event, self, cx);
4279                if !cx.propagate_event {
4280                    return;
4281                }
4282            }
4283        }
4284    }
4285
4286    /// Determine whether a potential multi-stroke key binding is in progress on this window.
4287    pub fn has_pending_keystrokes(&self) -> bool {
4288        self.pending_input.is_some()
4289    }
4290
4291    pub(crate) fn clear_pending_keystrokes(&mut self) {
4292        self.pending_input.take();
4293    }
4294
4295    /// Returns the currently pending input keystrokes that might result in a multi-stroke key binding.
4296    pub fn pending_input_keystrokes(&self) -> Option<&[Keystroke]> {
4297        self.pending_input
4298            .as_ref()
4299            .map(|pending_input| pending_input.keystrokes.as_slice())
4300    }
4301
4302    fn replay_pending_input(&mut self, replays: SmallVec<[Replay; 1]>, cx: &mut App) {
4303        let node_id = self.focus_node_id_in_rendered_frame(self.focus);
4304        let dispatch_path = self.rendered_frame.dispatch_tree.dispatch_path(node_id);
4305
4306        'replay: for replay in replays {
4307            let event = KeyDownEvent {
4308                keystroke: replay.keystroke.clone(),
4309                is_held: false,
4310                prefer_character_input: true,
4311            };
4312
4313            cx.propagate_event = true;
4314            for binding in replay.bindings {
4315                self.dispatch_action_on_node(node_id, binding.action.as_ref(), cx);
4316                if !cx.propagate_event {
4317                    self.dispatch_keystroke_observers(
4318                        &event,
4319                        Some(binding.action),
4320                        Vec::default(),
4321                        cx,
4322                    );
4323                    continue 'replay;
4324                }
4325            }
4326
4327            self.dispatch_key_down_up_event(&event, &dispatch_path, cx);
4328            if !cx.propagate_event {
4329                continue 'replay;
4330            }
4331            if let Some(input) = replay.keystroke.key_char.as_ref().cloned()
4332                && let Some(mut input_handler) = self.platform_window.take_input_handler()
4333            {
4334                input_handler.dispatch_input(&input, self, cx);
4335                self.platform_window.set_input_handler(input_handler)
4336            }
4337        }
4338    }
4339
4340    fn focus_node_id_in_rendered_frame(&self, focus_id: Option<FocusId>) -> DispatchNodeId {
4341        focus_id
4342            .and_then(|focus_id| {
4343                self.rendered_frame
4344                    .dispatch_tree
4345                    .focusable_node_id(focus_id)
4346            })
4347            .unwrap_or_else(|| self.rendered_frame.dispatch_tree.root_node_id())
4348    }
4349
4350    fn dispatch_action_on_node(
4351        &mut self,
4352        node_id: DispatchNodeId,
4353        action: &dyn Action,
4354        cx: &mut App,
4355    ) {
4356        let dispatch_path = self.rendered_frame.dispatch_tree.dispatch_path(node_id);
4357
4358        // Capture phase for global actions.
4359        cx.propagate_event = true;
4360        if let Some(mut global_listeners) = cx
4361            .global_action_listeners
4362            .remove(&action.as_any().type_id())
4363        {
4364            for listener in &global_listeners {
4365                listener(action.as_any(), DispatchPhase::Capture, cx);
4366                if !cx.propagate_event {
4367                    break;
4368                }
4369            }
4370
4371            global_listeners.extend(
4372                cx.global_action_listeners
4373                    .remove(&action.as_any().type_id())
4374                    .unwrap_or_default(),
4375            );
4376
4377            cx.global_action_listeners
4378                .insert(action.as_any().type_id(), global_listeners);
4379        }
4380
4381        if !cx.propagate_event {
4382            return;
4383        }
4384
4385        // Capture phase for window actions.
4386        for node_id in &dispatch_path {
4387            let node = self.rendered_frame.dispatch_tree.node(*node_id);
4388            for DispatchActionListener {
4389                action_type,
4390                listener,
4391            } in node.action_listeners.clone()
4392            {
4393                let any_action = action.as_any();
4394                if action_type == any_action.type_id() {
4395                    listener(any_action, DispatchPhase::Capture, self, cx);
4396
4397                    if !cx.propagate_event {
4398                        return;
4399                    }
4400                }
4401            }
4402        }
4403
4404        // Bubble phase for window actions.
4405        for node_id in dispatch_path.iter().rev() {
4406            let node = self.rendered_frame.dispatch_tree.node(*node_id);
4407            for DispatchActionListener {
4408                action_type,
4409                listener,
4410            } in node.action_listeners.clone()
4411            {
4412                let any_action = action.as_any();
4413                if action_type == any_action.type_id() {
4414                    cx.propagate_event = false; // Actions stop propagation by default during the bubble phase
4415                    listener(any_action, DispatchPhase::Bubble, self, cx);
4416
4417                    if !cx.propagate_event {
4418                        return;
4419                    }
4420                }
4421            }
4422        }
4423
4424        // Bubble phase for global actions.
4425        if let Some(mut global_listeners) = cx
4426            .global_action_listeners
4427            .remove(&action.as_any().type_id())
4428        {
4429            for listener in global_listeners.iter().rev() {
4430                cx.propagate_event = false; // Actions stop propagation by default during the bubble phase
4431
4432                listener(action.as_any(), DispatchPhase::Bubble, cx);
4433                if !cx.propagate_event {
4434                    break;
4435                }
4436            }
4437
4438            global_listeners.extend(
4439                cx.global_action_listeners
4440                    .remove(&action.as_any().type_id())
4441                    .unwrap_or_default(),
4442            );
4443
4444            cx.global_action_listeners
4445                .insert(action.as_any().type_id(), global_listeners);
4446        }
4447    }
4448
4449    /// Register the given handler to be invoked whenever the global of the given type
4450    /// is updated.
4451    pub fn observe_global<G: Global>(
4452        &mut self,
4453        cx: &mut App,
4454        f: impl Fn(&mut Window, &mut App) + 'static,
4455    ) -> Subscription {
4456        let window_handle = self.handle;
4457        let (subscription, activate) = cx.global_observers.insert(
4458            TypeId::of::<G>(),
4459            Box::new(move |cx| {
4460                window_handle
4461                    .update(cx, |_, window, cx| f(window, cx))
4462                    .is_ok()
4463            }),
4464        );
4465        cx.defer(move |_| activate());
4466        subscription
4467    }
4468
4469    /// Focus the current window and bring it to the foreground at the platform level.
4470    pub fn activate_window(&self) {
4471        self.platform_window.activate();
4472    }
4473
4474    /// Minimize the current window at the platform level.
4475    pub fn minimize_window(&self) {
4476        self.platform_window.minimize();
4477    }
4478
4479    /// Toggle full screen status on the current window at the platform level.
4480    pub fn toggle_fullscreen(&self) {
4481        self.platform_window.toggle_fullscreen();
4482    }
4483
4484    /// Updates the IME panel position suggestions for languages like japanese, chinese.
4485    pub fn invalidate_character_coordinates(&self) {
4486        self.on_next_frame(|window, cx| {
4487            if let Some(mut input_handler) = window.platform_window.take_input_handler() {
4488                if let Some(bounds) = input_handler.selected_bounds(window, cx) {
4489                    window.platform_window.update_ime_position(bounds);
4490                }
4491                window.platform_window.set_input_handler(input_handler);
4492            }
4493        });
4494    }
4495
4496    /// Present a platform dialog.
4497    /// The provided message will be presented, along with buttons for each answer.
4498    /// When a button is clicked, the returned Receiver will receive the index of the clicked button.
4499    pub fn prompt<T>(
4500        &mut self,
4501        level: PromptLevel,
4502        message: &str,
4503        detail: Option<&str>,
4504        answers: &[T],
4505        cx: &mut App,
4506    ) -> oneshot::Receiver<usize>
4507    where
4508        T: Clone + Into<PromptButton>,
4509    {
4510        let prompt_builder = cx.prompt_builder.take();
4511        let Some(prompt_builder) = prompt_builder else {
4512            unreachable!("Re-entrant window prompting is not supported by GPUI");
4513        };
4514
4515        let answers = answers
4516            .iter()
4517            .map(|answer| answer.clone().into())
4518            .collect::<Vec<_>>();
4519
4520        let receiver = match &prompt_builder {
4521            PromptBuilder::Default => self
4522                .platform_window
4523                .prompt(level, message, detail, &answers)
4524                .unwrap_or_else(|| {
4525                    self.build_custom_prompt(&prompt_builder, level, message, detail, &answers, cx)
4526                }),
4527            PromptBuilder::Custom(_) => {
4528                self.build_custom_prompt(&prompt_builder, level, message, detail, &answers, cx)
4529            }
4530        };
4531
4532        cx.prompt_builder = Some(prompt_builder);
4533
4534        receiver
4535    }
4536
4537    fn build_custom_prompt(
4538        &mut self,
4539        prompt_builder: &PromptBuilder,
4540        level: PromptLevel,
4541        message: &str,
4542        detail: Option<&str>,
4543        answers: &[PromptButton],
4544        cx: &mut App,
4545    ) -> oneshot::Receiver<usize> {
4546        let (sender, receiver) = oneshot::channel();
4547        let handle = PromptHandle::new(sender);
4548        let handle = (prompt_builder)(level, message, detail, answers, handle, self, cx);
4549        self.prompt = Some(handle);
4550        receiver
4551    }
4552
4553    /// Returns the current context stack.
4554    pub fn context_stack(&self) -> Vec<KeyContext> {
4555        let node_id = self.focus_node_id_in_rendered_frame(self.focus);
4556        let dispatch_tree = &self.rendered_frame.dispatch_tree;
4557        dispatch_tree
4558            .dispatch_path(node_id)
4559            .iter()
4560            .filter_map(move |&node_id| dispatch_tree.node(node_id).context.clone())
4561            .collect()
4562    }
4563
4564    /// Returns all available actions for the focused element.
4565    pub fn available_actions(&self, cx: &App) -> Vec<Box<dyn Action>> {
4566        let node_id = self.focus_node_id_in_rendered_frame(self.focus);
4567        let mut actions = self.rendered_frame.dispatch_tree.available_actions(node_id);
4568        for action_type in cx.global_action_listeners.keys() {
4569            if let Err(ix) = actions.binary_search_by_key(action_type, |a| a.as_any().type_id()) {
4570                let action = cx.actions.build_action_type(action_type).ok();
4571                if let Some(action) = action {
4572                    actions.insert(ix, action);
4573                }
4574            }
4575        }
4576        actions
4577    }
4578
4579    /// Returns key bindings that invoke an action on the currently focused element. Bindings are
4580    /// returned in the order they were added. For display, the last binding should take precedence.
4581    pub fn bindings_for_action(&self, action: &dyn Action) -> Vec<KeyBinding> {
4582        self.rendered_frame
4583            .dispatch_tree
4584            .bindings_for_action(action, &self.rendered_frame.dispatch_tree.context_stack)
4585    }
4586
4587    /// Returns the highest precedence key binding that invokes an action on the currently focused
4588    /// element. This is more efficient than getting the last result of `bindings_for_action`.
4589    pub fn highest_precedence_binding_for_action(&self, action: &dyn Action) -> Option<KeyBinding> {
4590        self.rendered_frame
4591            .dispatch_tree
4592            .highest_precedence_binding_for_action(
4593                action,
4594                &self.rendered_frame.dispatch_tree.context_stack,
4595            )
4596    }
4597
4598    /// Returns the key bindings for an action in a context.
4599    pub fn bindings_for_action_in_context(
4600        &self,
4601        action: &dyn Action,
4602        context: KeyContext,
4603    ) -> Vec<KeyBinding> {
4604        let dispatch_tree = &self.rendered_frame.dispatch_tree;
4605        dispatch_tree.bindings_for_action(action, &[context])
4606    }
4607
4608    /// Returns the highest precedence key binding for an action in a context. This is more
4609    /// efficient than getting the last result of `bindings_for_action_in_context`.
4610    pub fn highest_precedence_binding_for_action_in_context(
4611        &self,
4612        action: &dyn Action,
4613        context: KeyContext,
4614    ) -> Option<KeyBinding> {
4615        let dispatch_tree = &self.rendered_frame.dispatch_tree;
4616        dispatch_tree.highest_precedence_binding_for_action(action, &[context])
4617    }
4618
4619    /// Returns any bindings that would invoke an action on the given focus handle if it were
4620    /// focused. Bindings are returned in the order they were added. For display, the last binding
4621    /// should take precedence.
4622    pub fn bindings_for_action_in(
4623        &self,
4624        action: &dyn Action,
4625        focus_handle: &FocusHandle,
4626    ) -> Vec<KeyBinding> {
4627        let dispatch_tree = &self.rendered_frame.dispatch_tree;
4628        let Some(context_stack) = self.context_stack_for_focus_handle(focus_handle) else {
4629            return vec![];
4630        };
4631        dispatch_tree.bindings_for_action(action, &context_stack)
4632    }
4633
4634    /// Returns the highest precedence key binding that would invoke an action on the given focus
4635    /// handle if it were focused. This is more efficient than getting the last result of
4636    /// `bindings_for_action_in`.
4637    pub fn highest_precedence_binding_for_action_in(
4638        &self,
4639        action: &dyn Action,
4640        focus_handle: &FocusHandle,
4641    ) -> Option<KeyBinding> {
4642        let dispatch_tree = &self.rendered_frame.dispatch_tree;
4643        let context_stack = self.context_stack_for_focus_handle(focus_handle)?;
4644        dispatch_tree.highest_precedence_binding_for_action(action, &context_stack)
4645    }
4646
4647    /// Find the bindings that can follow the current input sequence for the current context stack.
4648    pub fn possible_bindings_for_input(&self, input: &[Keystroke]) -> Vec<KeyBinding> {
4649        self.rendered_frame
4650            .dispatch_tree
4651            .possible_next_bindings_for_input(input, &self.context_stack())
4652    }
4653
4654    fn context_stack_for_focus_handle(
4655        &self,
4656        focus_handle: &FocusHandle,
4657    ) -> Option<Vec<KeyContext>> {
4658        let dispatch_tree = &self.rendered_frame.dispatch_tree;
4659        let node_id = dispatch_tree.focusable_node_id(focus_handle.id)?;
4660        let context_stack: Vec<_> = dispatch_tree
4661            .dispatch_path(node_id)
4662            .into_iter()
4663            .filter_map(|node_id| dispatch_tree.node(node_id).context.clone())
4664            .collect();
4665        Some(context_stack)
4666    }
4667
4668    /// Returns a generic event listener that invokes the given listener with the view and context associated with the given view handle.
4669    pub fn listener_for<T: 'static, E>(
4670        &self,
4671        view: &Entity<T>,
4672        f: impl Fn(&mut T, &E, &mut Window, &mut Context<T>) + 'static,
4673    ) -> impl Fn(&E, &mut Window, &mut App) + 'static {
4674        let view = view.downgrade();
4675        move |e: &E, window: &mut Window, cx: &mut App| {
4676            view.update(cx, |view, cx| f(view, e, window, cx)).ok();
4677        }
4678    }
4679
4680    /// Returns a generic handler that invokes the given handler with the view and context associated with the given view handle.
4681    pub fn handler_for<E: 'static, Callback: Fn(&mut E, &mut Window, &mut Context<E>) + 'static>(
4682        &self,
4683        entity: &Entity<E>,
4684        f: Callback,
4685    ) -> impl Fn(&mut Window, &mut App) + 'static {
4686        let entity = entity.downgrade();
4687        move |window: &mut Window, cx: &mut App| {
4688            entity.update(cx, |entity, cx| f(entity, window, cx)).ok();
4689        }
4690    }
4691
4692    /// Register a callback that can interrupt the closing of the current window based the returned boolean.
4693    /// If the callback returns false, the window won't be closed.
4694    pub fn on_window_should_close(
4695        &self,
4696        cx: &App,
4697        f: impl Fn(&mut Window, &mut App) -> bool + 'static,
4698    ) {
4699        let mut cx = self.to_async(cx);
4700        self.platform_window.on_should_close(Box::new(move || {
4701            cx.update(|window, cx| f(window, cx)).unwrap_or(true)
4702        }))
4703    }
4704
4705    /// Register an action listener on this node for the next frame. The type of action
4706    /// is determined by the first parameter of the given listener. When the next frame is rendered
4707    /// the listener will be cleared.
4708    ///
4709    /// This is a fairly low-level method, so prefer using action handlers on elements unless you have
4710    /// a specific need to register a listener yourself.
4711    ///
4712    /// This method should only be called as part of the paint phase of element drawing.
4713    pub fn on_action(
4714        &mut self,
4715        action_type: TypeId,
4716        listener: impl Fn(&dyn Any, DispatchPhase, &mut Window, &mut App) + 'static,
4717    ) {
4718        self.invalidator.debug_assert_paint();
4719
4720        self.next_frame
4721            .dispatch_tree
4722            .on_action(action_type, Rc::new(listener));
4723    }
4724
4725    /// Register a capturing action listener on this node for the next frame if the condition is true.
4726    /// The type of action is determined by the first parameter of the given listener. When the next
4727    /// frame is rendered the listener will be cleared.
4728    ///
4729    /// This is a fairly low-level method, so prefer using action handlers on elements unless you have
4730    /// a specific need to register a listener yourself.
4731    ///
4732    /// This method should only be called as part of the paint phase of element drawing.
4733    pub fn on_action_when(
4734        &mut self,
4735        condition: bool,
4736        action_type: TypeId,
4737        listener: impl Fn(&dyn Any, DispatchPhase, &mut Window, &mut App) + 'static,
4738    ) {
4739        self.invalidator.debug_assert_paint();
4740
4741        if condition {
4742            self.next_frame
4743                .dispatch_tree
4744                .on_action(action_type, Rc::new(listener));
4745        }
4746    }
4747
4748    /// Read information about the GPU backing this window.
4749    /// Currently returns None on Mac and Windows.
4750    pub fn gpu_specs(&self) -> Option<GpuSpecs> {
4751        self.platform_window.gpu_specs()
4752    }
4753
4754    /// Perform titlebar double-click action.
4755    /// This is macOS specific.
4756    pub fn titlebar_double_click(&self) {
4757        self.platform_window.titlebar_double_click();
4758    }
4759
4760    /// Gets the window's title at the platform level.
4761    /// This is macOS specific.
4762    pub fn window_title(&self) -> String {
4763        self.platform_window.get_title()
4764    }
4765
4766    /// Returns a list of all tabbed windows and their titles.
4767    /// This is macOS specific.
4768    pub fn tabbed_windows(&self) -> Option<Vec<SystemWindowTab>> {
4769        self.platform_window.tabbed_windows()
4770    }
4771
4772    /// Returns the tab bar visibility.
4773    /// This is macOS specific.
4774    pub fn tab_bar_visible(&self) -> bool {
4775        self.platform_window.tab_bar_visible()
4776    }
4777
4778    /// Merges all open windows into a single tabbed window.
4779    /// This is macOS specific.
4780    pub fn merge_all_windows(&self) {
4781        self.platform_window.merge_all_windows()
4782    }
4783
4784    /// Moves the tab to a new containing window.
4785    /// This is macOS specific.
4786    pub fn move_tab_to_new_window(&self) {
4787        self.platform_window.move_tab_to_new_window()
4788    }
4789
4790    /// Shows or hides the window tab overview.
4791    /// This is macOS specific.
4792    pub fn toggle_window_tab_overview(&self) {
4793        self.platform_window.toggle_window_tab_overview()
4794    }
4795
4796    /// Sets the tabbing identifier for the window.
4797    /// This is macOS specific.
4798    pub fn set_tabbing_identifier(&self, tabbing_identifier: Option<String>) {
4799        self.platform_window
4800            .set_tabbing_identifier(tabbing_identifier)
4801    }
4802
4803    /// Toggles the inspector mode on this window.
4804    #[cfg(any(feature = "inspector", debug_assertions))]
4805    pub fn toggle_inspector(&mut self, cx: &mut App) {
4806        self.inspector = match self.inspector {
4807            None => Some(cx.new(|_| Inspector::new())),
4808            Some(_) => None,
4809        };
4810        self.refresh();
4811    }
4812
4813    /// Returns true if the window is in inspector mode.
4814    pub fn is_inspector_picking(&self, _cx: &App) -> bool {
4815        #[cfg(any(feature = "inspector", debug_assertions))]
4816        {
4817            if let Some(inspector) = &self.inspector {
4818                return inspector.read(_cx).is_picking();
4819            }
4820        }
4821        false
4822    }
4823
4824    /// Executes the provided function with mutable access to an inspector state.
4825    #[cfg(any(feature = "inspector", debug_assertions))]
4826    pub fn with_inspector_state<T: 'static, R>(
4827        &mut self,
4828        _inspector_id: Option<&crate::InspectorElementId>,
4829        cx: &mut App,
4830        f: impl FnOnce(&mut Option<T>, &mut Self) -> R,
4831    ) -> R {
4832        if let Some(inspector_id) = _inspector_id
4833            && let Some(inspector) = &self.inspector
4834        {
4835            let inspector = inspector.clone();
4836            let active_element_id = inspector.read(cx).active_element_id();
4837            if Some(inspector_id) == active_element_id {
4838                return inspector.update(cx, |inspector, _cx| {
4839                    inspector.with_active_element_state(self, f)
4840                });
4841            }
4842        }
4843        f(&mut None, self)
4844    }
4845
4846    #[cfg(any(feature = "inspector", debug_assertions))]
4847    pub(crate) fn build_inspector_element_id(
4848        &mut self,
4849        path: crate::InspectorElementPath,
4850    ) -> crate::InspectorElementId {
4851        self.invalidator.debug_assert_paint_or_prepaint();
4852        let path = Rc::new(path);
4853        let next_instance_id = self
4854            .next_frame
4855            .next_inspector_instance_ids
4856            .entry(path.clone())
4857            .or_insert(0);
4858        let instance_id = *next_instance_id;
4859        *next_instance_id += 1;
4860        crate::InspectorElementId { path, instance_id }
4861    }
4862
4863    #[cfg(any(feature = "inspector", debug_assertions))]
4864    fn prepaint_inspector(&mut self, inspector_width: Pixels, cx: &mut App) -> Option<AnyElement> {
4865        if let Some(inspector) = self.inspector.take() {
4866            let mut inspector_element = AnyView::from(inspector.clone()).into_any_element();
4867            inspector_element.prepaint_as_root(
4868                point(self.viewport_size.width - inspector_width, px(0.0)),
4869                size(inspector_width, self.viewport_size.height).into(),
4870                self,
4871                cx,
4872            );
4873            self.inspector = Some(inspector);
4874            Some(inspector_element)
4875        } else {
4876            None
4877        }
4878    }
4879
4880    #[cfg(any(feature = "inspector", debug_assertions))]
4881    fn paint_inspector(&mut self, mut inspector_element: Option<AnyElement>, cx: &mut App) {
4882        if let Some(mut inspector_element) = inspector_element {
4883            inspector_element.paint(self, cx);
4884        };
4885    }
4886
4887    /// Registers a hitbox that can be used for inspector picking mode, allowing users to select and
4888    /// inspect UI elements by clicking on them.
4889    #[cfg(any(feature = "inspector", debug_assertions))]
4890    pub fn insert_inspector_hitbox(
4891        &mut self,
4892        hitbox_id: HitboxId,
4893        inspector_id: Option<&crate::InspectorElementId>,
4894        cx: &App,
4895    ) {
4896        self.invalidator.debug_assert_paint_or_prepaint();
4897        if !self.is_inspector_picking(cx) {
4898            return;
4899        }
4900        if let Some(inspector_id) = inspector_id {
4901            self.next_frame
4902                .inspector_hitboxes
4903                .insert(hitbox_id, inspector_id.clone());
4904        }
4905    }
4906
4907    #[cfg(any(feature = "inspector", debug_assertions))]
4908    fn paint_inspector_hitbox(&mut self, cx: &App) {
4909        if let Some(inspector) = self.inspector.as_ref() {
4910            let inspector = inspector.read(cx);
4911            if let Some((hitbox_id, _)) = self.hovered_inspector_hitbox(inspector, &self.next_frame)
4912                && let Some(hitbox) = self
4913                    .next_frame
4914                    .hitboxes
4915                    .iter()
4916                    .find(|hitbox| hitbox.id == hitbox_id)
4917            {
4918                self.paint_quad(crate::fill(hitbox.bounds, crate::rgba(0x61afef4d)));
4919            }
4920        }
4921    }
4922
4923    #[cfg(any(feature = "inspector", debug_assertions))]
4924    fn handle_inspector_mouse_event(&mut self, event: &dyn Any, cx: &mut App) {
4925        let Some(inspector) = self.inspector.clone() else {
4926            return;
4927        };
4928        if event.downcast_ref::<MouseMoveEvent>().is_some() {
4929            inspector.update(cx, |inspector, _cx| {
4930                if let Some((_, inspector_id)) =
4931                    self.hovered_inspector_hitbox(inspector, &self.rendered_frame)
4932                {
4933                    inspector.hover(inspector_id, self);
4934                }
4935            });
4936        } else if event.downcast_ref::<crate::MouseDownEvent>().is_some() {
4937            inspector.update(cx, |inspector, _cx| {
4938                if let Some((_, inspector_id)) =
4939                    self.hovered_inspector_hitbox(inspector, &self.rendered_frame)
4940                {
4941                    inspector.select(inspector_id, self);
4942                }
4943            });
4944        } else if let Some(event) = event.downcast_ref::<crate::ScrollWheelEvent>() {
4945            // This should be kept in sync with SCROLL_LINES in x11 platform.
4946            const SCROLL_LINES: f32 = 3.0;
4947            const SCROLL_PIXELS_PER_LAYER: f32 = 36.0;
4948            let delta_y = event
4949                .delta
4950                .pixel_delta(px(SCROLL_PIXELS_PER_LAYER / SCROLL_LINES))
4951                .y;
4952            if let Some(inspector) = self.inspector.clone() {
4953                inspector.update(cx, |inspector, _cx| {
4954                    if let Some(depth) = inspector.pick_depth.as_mut() {
4955                        *depth += f32::from(delta_y) / SCROLL_PIXELS_PER_LAYER;
4956                        let max_depth = self.mouse_hit_test.ids.len() as f32 - 0.5;
4957                        if *depth < 0.0 {
4958                            *depth = 0.0;
4959                        } else if *depth > max_depth {
4960                            *depth = max_depth;
4961                        }
4962                        if let Some((_, inspector_id)) =
4963                            self.hovered_inspector_hitbox(inspector, &self.rendered_frame)
4964                        {
4965                            inspector.set_active_element_id(inspector_id, self);
4966                        }
4967                    }
4968                });
4969            }
4970        }
4971    }
4972
4973    #[cfg(any(feature = "inspector", debug_assertions))]
4974    fn hovered_inspector_hitbox(
4975        &self,
4976        inspector: &Inspector,
4977        frame: &Frame,
4978    ) -> Option<(HitboxId, crate::InspectorElementId)> {
4979        if let Some(pick_depth) = inspector.pick_depth {
4980            let depth = (pick_depth as i64).try_into().unwrap_or(0);
4981            let max_skipped = self.mouse_hit_test.ids.len().saturating_sub(1);
4982            let skip_count = (depth as usize).min(max_skipped);
4983            for hitbox_id in self.mouse_hit_test.ids.iter().skip(skip_count) {
4984                if let Some(inspector_id) = frame.inspector_hitboxes.get(hitbox_id) {
4985                    return Some((*hitbox_id, inspector_id.clone()));
4986                }
4987            }
4988        }
4989        None
4990    }
4991
4992    /// For testing: set the current modifier keys state.
4993    /// This does not generate any events.
4994    #[cfg(any(test, feature = "test-support"))]
4995    pub fn set_modifiers(&mut self, modifiers: Modifiers) {
4996        self.modifiers = modifiers;
4997    }
4998
4999    /// For testing: simulate a mouse move event to the given position.
5000    /// This dispatches the event through the normal event handling path,
5001    /// which will trigger hover states and tooltips.
5002    #[cfg(any(test, feature = "test-support"))]
5003    pub fn simulate_mouse_move(&mut self, position: Point<Pixels>, cx: &mut App) {
5004        let event = PlatformInput::MouseMove(MouseMoveEvent {
5005            position,
5006            modifiers: self.modifiers,
5007            pressed_button: None,
5008        });
5009        let _ = self.dispatch_event(event, cx);
5010    }
5011}
5012
5013// #[derive(Clone, Copy, Eq, PartialEq, Hash)]
5014slotmap::new_key_type! {
5015    /// A unique identifier for a window.
5016    pub struct WindowId;
5017}
5018
5019impl WindowId {
5020    /// Converts this window ID to a `u64`.
5021    pub fn as_u64(&self) -> u64 {
5022        self.0.as_ffi()
5023    }
5024}
5025
5026impl From<u64> for WindowId {
5027    fn from(value: u64) -> Self {
5028        WindowId(slotmap::KeyData::from_ffi(value))
5029    }
5030}
5031
5032/// A handle to a window with a specific root view type.
5033/// Note that this does not keep the window alive on its own.
5034#[derive(Deref, DerefMut)]
5035pub struct WindowHandle<V> {
5036    #[deref]
5037    #[deref_mut]
5038    pub(crate) any_handle: AnyWindowHandle,
5039    state_type: PhantomData<fn(V) -> V>,
5040}
5041
5042impl<V> Debug for WindowHandle<V> {
5043    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
5044        f.debug_struct("WindowHandle")
5045            .field("any_handle", &self.any_handle.id.as_u64())
5046            .finish()
5047    }
5048}
5049
5050impl<V: 'static + Render> WindowHandle<V> {
5051    /// Creates a new handle from a window ID.
5052    /// This does not check if the root type of the window is `V`.
5053    pub fn new(id: WindowId) -> Self {
5054        WindowHandle {
5055            any_handle: AnyWindowHandle {
5056                id,
5057                state_type: TypeId::of::<V>(),
5058            },
5059            state_type: PhantomData,
5060        }
5061    }
5062
5063    /// Get the root view out of this window.
5064    ///
5065    /// This will fail if the window is closed or if the root view's type does not match `V`.
5066    #[cfg(any(test, feature = "test-support"))]
5067    pub fn root<C>(&self, cx: &mut C) -> Result<Entity<V>>
5068    where
5069        C: AppContext,
5070    {
5071        cx.update_window(self.any_handle, |root_view, _, _| {
5072            root_view
5073                .downcast::<V>()
5074                .map_err(|_| anyhow!("the type of the window's root view has changed"))
5075        })?
5076    }
5077
5078    /// Updates the root view of this window.
5079    ///
5080    /// This will fail if the window has been closed or if the root view's type does not match
5081    pub fn update<C, R>(
5082        &self,
5083        cx: &mut C,
5084        update: impl FnOnce(&mut V, &mut Window, &mut Context<V>) -> R,
5085    ) -> Result<R>
5086    where
5087        C: AppContext,
5088    {
5089        cx.update_window(self.any_handle, |root_view, window, cx| {
5090            let view = root_view
5091                .downcast::<V>()
5092                .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
5093
5094            Ok(view.update(cx, |view, cx| update(view, window, cx)))
5095        })?
5096    }
5097
5098    /// Read the root view out of this window.
5099    ///
5100    /// This will fail if the window is closed or if the root view's type does not match `V`.
5101    pub fn read<'a>(&self, cx: &'a App) -> Result<&'a V> {
5102        let x = cx
5103            .windows
5104            .get(self.id)
5105            .and_then(|window| {
5106                window
5107                    .as_deref()
5108                    .and_then(|window| window.root.clone())
5109                    .map(|root_view| root_view.downcast::<V>())
5110            })
5111            .context("window not found")?
5112            .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
5113
5114        Ok(x.read(cx))
5115    }
5116
5117    /// Read the root view out of this window, with a callback
5118    ///
5119    /// This will fail if the window is closed or if the root view's type does not match `V`.
5120    pub fn read_with<C, R>(&self, cx: &C, read_with: impl FnOnce(&V, &App) -> R) -> Result<R>
5121    where
5122        C: AppContext,
5123    {
5124        cx.read_window(self, |root_view, cx| read_with(root_view.read(cx), cx))
5125    }
5126
5127    /// Read the root view pointer off of this window.
5128    ///
5129    /// This will fail if the window is closed or if the root view's type does not match `V`.
5130    pub fn entity<C>(&self, cx: &C) -> Result<Entity<V>>
5131    where
5132        C: AppContext,
5133    {
5134        cx.read_window(self, |root_view, _cx| root_view)
5135    }
5136
5137    /// Check if this window is 'active'.
5138    ///
5139    /// Will return `None` if the window is closed or currently
5140    /// borrowed.
5141    pub fn is_active(&self, cx: &mut App) -> Option<bool> {
5142        cx.update_window(self.any_handle, |_, window, _| window.is_window_active())
5143            .ok()
5144    }
5145}
5146
5147impl<V> Copy for WindowHandle<V> {}
5148
5149impl<V> Clone for WindowHandle<V> {
5150    fn clone(&self) -> Self {
5151        *self
5152    }
5153}
5154
5155impl<V> PartialEq for WindowHandle<V> {
5156    fn eq(&self, other: &Self) -> bool {
5157        self.any_handle == other.any_handle
5158    }
5159}
5160
5161impl<V> Eq for WindowHandle<V> {}
5162
5163impl<V> Hash for WindowHandle<V> {
5164    fn hash<H: Hasher>(&self, state: &mut H) {
5165        self.any_handle.hash(state);
5166    }
5167}
5168
5169impl<V: 'static> From<WindowHandle<V>> for AnyWindowHandle {
5170    fn from(val: WindowHandle<V>) -> Self {
5171        val.any_handle
5172    }
5173}
5174
5175/// A handle to a window with any root view type, which can be downcast to a window with a specific root view type.
5176#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
5177pub struct AnyWindowHandle {
5178    pub(crate) id: WindowId,
5179    state_type: TypeId,
5180}
5181
5182impl AnyWindowHandle {
5183    /// Get the ID of this window.
5184    pub fn window_id(&self) -> WindowId {
5185        self.id
5186    }
5187
5188    /// Attempt to convert this handle to a window handle with a specific root view type.
5189    /// If the types do not match, this will return `None`.
5190    pub fn downcast<T: 'static>(&self) -> Option<WindowHandle<T>> {
5191        if TypeId::of::<T>() == self.state_type {
5192            Some(WindowHandle {
5193                any_handle: *self,
5194                state_type: PhantomData,
5195            })
5196        } else {
5197            None
5198        }
5199    }
5200
5201    /// Updates the state of the root view of this window.
5202    ///
5203    /// This will fail if the window has been closed.
5204    pub fn update<C, R>(
5205        self,
5206        cx: &mut C,
5207        update: impl FnOnce(AnyView, &mut Window, &mut App) -> R,
5208    ) -> Result<R>
5209    where
5210        C: AppContext,
5211    {
5212        cx.update_window(self, update)
5213    }
5214
5215    /// Read the state of the root view of this window.
5216    ///
5217    /// This will fail if the window has been closed.
5218    pub fn read<T, C, R>(self, cx: &C, read: impl FnOnce(Entity<T>, &App) -> R) -> Result<R>
5219    where
5220        C: AppContext,
5221        T: 'static,
5222    {
5223        let view = self
5224            .downcast::<T>()
5225            .context("the type of the window's root view has changed")?;
5226
5227        cx.read_window(&view, read)
5228    }
5229}
5230
5231impl HasWindowHandle for Window {
5232    fn window_handle(&self) -> Result<raw_window_handle::WindowHandle<'_>, HandleError> {
5233        self.platform_window.window_handle()
5234    }
5235}
5236
5237impl HasDisplayHandle for Window {
5238    fn display_handle(
5239        &self,
5240    ) -> std::result::Result<raw_window_handle::DisplayHandle<'_>, HandleError> {
5241        self.platform_window.display_handle()
5242    }
5243}
5244
5245/// An identifier for an [`Element`].
5246///
5247/// Can be constructed with a string, a number, or both, as well
5248/// as other internal representations.
5249#[derive(Clone, Debug, Eq, PartialEq, Hash)]
5250pub enum ElementId {
5251    /// The ID of a View element
5252    View(EntityId),
5253    /// An integer ID.
5254    Integer(u64),
5255    /// A string based ID.
5256    Name(SharedString),
5257    /// A UUID.
5258    Uuid(Uuid),
5259    /// An ID that's equated with a focus handle.
5260    FocusHandle(FocusId),
5261    /// A combination of a name and an integer.
5262    NamedInteger(SharedString, u64),
5263    /// A path.
5264    Path(Arc<std::path::Path>),
5265    /// A code location.
5266    CodeLocation(core::panic::Location<'static>),
5267    /// A labeled child of an element.
5268    NamedChild(Arc<ElementId>, SharedString),
5269}
5270
5271impl ElementId {
5272    /// Constructs an `ElementId::NamedInteger` from a name and `usize`.
5273    pub fn named_usize(name: impl Into<SharedString>, integer: usize) -> ElementId {
5274        Self::NamedInteger(name.into(), integer as u64)
5275    }
5276}
5277
5278impl Display for ElementId {
5279    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
5280        match self {
5281            ElementId::View(entity_id) => write!(f, "view-{}", entity_id)?,
5282            ElementId::Integer(ix) => write!(f, "{}", ix)?,
5283            ElementId::Name(name) => write!(f, "{}", name)?,
5284            ElementId::FocusHandle(_) => write!(f, "FocusHandle")?,
5285            ElementId::NamedInteger(s, i) => write!(f, "{}-{}", s, i)?,
5286            ElementId::Uuid(uuid) => write!(f, "{}", uuid)?,
5287            ElementId::Path(path) => write!(f, "{}", path.display())?,
5288            ElementId::CodeLocation(location) => write!(f, "{}", location)?,
5289            ElementId::NamedChild(id, name) => write!(f, "{}-{}", id, name)?,
5290        }
5291
5292        Ok(())
5293    }
5294}
5295
5296impl TryInto<SharedString> for ElementId {
5297    type Error = anyhow::Error;
5298
5299    fn try_into(self) -> anyhow::Result<SharedString> {
5300        if let ElementId::Name(name) = self {
5301            Ok(name)
5302        } else {
5303            anyhow::bail!("element id is not string")
5304        }
5305    }
5306}
5307
5308impl From<usize> for ElementId {
5309    fn from(id: usize) -> Self {
5310        ElementId::Integer(id as u64)
5311    }
5312}
5313
5314impl From<i32> for ElementId {
5315    fn from(id: i32) -> Self {
5316        Self::Integer(id as u64)
5317    }
5318}
5319
5320impl From<SharedString> for ElementId {
5321    fn from(name: SharedString) -> Self {
5322        ElementId::Name(name)
5323    }
5324}
5325
5326impl From<String> for ElementId {
5327    fn from(name: String) -> Self {
5328        ElementId::Name(name.into())
5329    }
5330}
5331
5332impl From<Arc<str>> for ElementId {
5333    fn from(name: Arc<str>) -> Self {
5334        ElementId::Name(name.into())
5335    }
5336}
5337
5338impl From<Arc<std::path::Path>> for ElementId {
5339    fn from(path: Arc<std::path::Path>) -> Self {
5340        ElementId::Path(path)
5341    }
5342}
5343
5344impl From<&'static str> for ElementId {
5345    fn from(name: &'static str) -> Self {
5346        ElementId::Name(name.into())
5347    }
5348}
5349
5350impl<'a> From<&'a FocusHandle> for ElementId {
5351    fn from(handle: &'a FocusHandle) -> Self {
5352        ElementId::FocusHandle(handle.id)
5353    }
5354}
5355
5356impl From<(&'static str, EntityId)> for ElementId {
5357    fn from((name, id): (&'static str, EntityId)) -> Self {
5358        ElementId::NamedInteger(name.into(), id.as_u64())
5359    }
5360}
5361
5362impl From<(&'static str, usize)> for ElementId {
5363    fn from((name, id): (&'static str, usize)) -> Self {
5364        ElementId::NamedInteger(name.into(), id as u64)
5365    }
5366}
5367
5368impl From<(SharedString, usize)> for ElementId {
5369    fn from((name, id): (SharedString, usize)) -> Self {
5370        ElementId::NamedInteger(name, id as u64)
5371    }
5372}
5373
5374impl From<(&'static str, u64)> for ElementId {
5375    fn from((name, id): (&'static str, u64)) -> Self {
5376        ElementId::NamedInteger(name.into(), id)
5377    }
5378}
5379
5380impl From<Uuid> for ElementId {
5381    fn from(value: Uuid) -> Self {
5382        Self::Uuid(value)
5383    }
5384}
5385
5386impl From<(&'static str, u32)> for ElementId {
5387    fn from((name, id): (&'static str, u32)) -> Self {
5388        ElementId::NamedInteger(name.into(), id.into())
5389    }
5390}
5391
5392impl<T: Into<SharedString>> From<(ElementId, T)> for ElementId {
5393    fn from((id, name): (ElementId, T)) -> Self {
5394        ElementId::NamedChild(Arc::new(id), name.into())
5395    }
5396}
5397
5398impl From<&'static core::panic::Location<'static>> for ElementId {
5399    fn from(location: &'static core::panic::Location<'static>) -> Self {
5400        ElementId::CodeLocation(*location)
5401    }
5402}
5403
5404/// A rectangle to be rendered in the window at the given position and size.
5405/// Passed as an argument [`Window::paint_quad`].
5406#[derive(Clone)]
5407pub struct PaintQuad {
5408    /// The bounds of the quad within the window.
5409    pub bounds: Bounds<Pixels>,
5410    /// The radii of the quad's corners.
5411    pub corner_radii: Corners<Pixels>,
5412    /// The background color of the quad.
5413    pub background: Background,
5414    /// The widths of the quad's borders.
5415    pub border_widths: Edges<Pixels>,
5416    /// The color of the quad's borders.
5417    pub border_color: Hsla,
5418    /// The style of the quad's borders.
5419    pub border_style: BorderStyle,
5420}
5421
5422impl PaintQuad {
5423    /// Sets the corner radii of the quad.
5424    pub fn corner_radii(self, corner_radii: impl Into<Corners<Pixels>>) -> Self {
5425        PaintQuad {
5426            corner_radii: corner_radii.into(),
5427            ..self
5428        }
5429    }
5430
5431    /// Sets the border widths of the quad.
5432    pub fn border_widths(self, border_widths: impl Into<Edges<Pixels>>) -> Self {
5433        PaintQuad {
5434            border_widths: border_widths.into(),
5435            ..self
5436        }
5437    }
5438
5439    /// Sets the border color of the quad.
5440    pub fn border_color(self, border_color: impl Into<Hsla>) -> Self {
5441        PaintQuad {
5442            border_color: border_color.into(),
5443            ..self
5444        }
5445    }
5446
5447    /// Sets the background color of the quad.
5448    pub fn background(self, background: impl Into<Background>) -> Self {
5449        PaintQuad {
5450            background: background.into(),
5451            ..self
5452        }
5453    }
5454}
5455
5456/// Creates a quad with the given parameters.
5457pub fn quad(
5458    bounds: Bounds<Pixels>,
5459    corner_radii: impl Into<Corners<Pixels>>,
5460    background: impl Into<Background>,
5461    border_widths: impl Into<Edges<Pixels>>,
5462    border_color: impl Into<Hsla>,
5463    border_style: BorderStyle,
5464) -> PaintQuad {
5465    PaintQuad {
5466        bounds,
5467        corner_radii: corner_radii.into(),
5468        background: background.into(),
5469        border_widths: border_widths.into(),
5470        border_color: border_color.into(),
5471        border_style,
5472    }
5473}
5474
5475/// Creates a filled quad with the given bounds and background color.
5476pub fn fill(bounds: impl Into<Bounds<Pixels>>, background: impl Into<Background>) -> PaintQuad {
5477    PaintQuad {
5478        bounds: bounds.into(),
5479        corner_radii: (0.).into(),
5480        background: background.into(),
5481        border_widths: (0.).into(),
5482        border_color: transparent_black(),
5483        border_style: BorderStyle::default(),
5484    }
5485}
5486
5487/// Creates a rectangle outline with the given bounds, border color, and a 1px border width
5488pub fn outline(
5489    bounds: impl Into<Bounds<Pixels>>,
5490    border_color: impl Into<Hsla>,
5491    border_style: BorderStyle,
5492) -> PaintQuad {
5493    PaintQuad {
5494        bounds: bounds.into(),
5495        corner_radii: (0.).into(),
5496        background: transparent_black().into(),
5497        border_widths: (1.).into(),
5498        border_color: border_color.into(),
5499        border_style,
5500    }
5501}