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