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