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