1use crate::{
2 px, size, Action, AnyBox, AnyDrag, AnyView, AppContext, AsyncWindowContext, AvailableSpace,
3 Bounds, BoxShadow, Context, Corners, CursorStyle, DevicePixels, DispatchContext, DisplayId,
4 Edges, Effect, Entity, EntityId, EventEmitter, FileDropEvent, FocusEvent, FontId,
5 GlobalElementId, GlyphId, Hsla, ImageData, InputEvent, IsZero, KeyListener, KeyMatch,
6 KeyMatcher, Keystroke, LayoutId, Model, ModelContext, Modifiers, MonochromeSprite, MouseButton,
7 MouseDownEvent, MouseMoveEvent, MouseUpEvent, Path, Pixels, PlatformAtlas, PlatformDisplay,
8 PlatformWindow, Point, PolychromeSprite, PromptLevel, Quad, Render, RenderGlyphParams,
9 RenderImageParams, RenderSvgParams, ScaledPixels, SceneBuilder, Shadow, SharedString, Size,
10 Style, SubscriberSet, Subscription, TaffyLayoutEngine, Task, Underline, UnderlineStyle, View,
11 VisualContext, WeakView, WindowBounds, WindowOptions, SUBPIXEL_VARIANTS,
12};
13use anyhow::{anyhow, Result};
14use collections::HashMap;
15use derive_more::{Deref, DerefMut};
16use futures::{
17 channel::{mpsc, oneshot},
18 StreamExt,
19};
20use parking_lot::RwLock;
21use slotmap::SlotMap;
22use smallvec::SmallVec;
23use std::{
24 any::{Any, TypeId},
25 borrow::{Borrow, BorrowMut, Cow},
26 fmt::Debug,
27 future::Future,
28 hash::{Hash, Hasher},
29 marker::PhantomData,
30 mem,
31 rc::Rc,
32 sync::{
33 atomic::{AtomicUsize, Ordering::SeqCst},
34 Arc,
35 },
36};
37use util::ResultExt;
38
39/// A global stacking order, which is created by stacking successive z-index values.
40/// Each z-index will always be interpreted in the context of its parent z-index.
41#[derive(Deref, DerefMut, Ord, PartialOrd, Eq, PartialEq, Clone, Default)]
42pub(crate) struct StackingOrder(pub(crate) SmallVec<[u32; 16]>);
43
44/// Represents the two different phases when dispatching events.
45#[derive(Default, Copy, Clone, Debug, Eq, PartialEq)]
46pub enum DispatchPhase {
47 /// After the capture phase comes the bubble phase, in which mouse event listeners are
48 /// invoked front to back and keyboard event listeners are invoked from the focused element
49 /// to the root of the element tree. This is the phase you'll most commonly want to use when
50 /// registering event listeners.
51 #[default]
52 Bubble,
53 /// During the initial capture phase, mouse event listeners are invoked back to front, and keyboard
54 /// listeners are invoked from the root of the tree downward toward the focused element. This phase
55 /// is used for special purposes such as clearing the "pressed" state for click events. If
56 /// you stop event propagation during this phase, you need to know what you're doing. Handlers
57 /// outside of the immediate region may rely on detecting non-local events during this phase.
58 Capture,
59}
60
61type AnyObserver = Box<dyn FnMut(&mut WindowContext) -> bool + 'static>;
62type AnyListener = Box<dyn Fn(&dyn Any, DispatchPhase, &mut WindowContext) + 'static>;
63type AnyKeyListener = Box<
64 dyn Fn(
65 &dyn Any,
66 &[&DispatchContext],
67 DispatchPhase,
68 &mut WindowContext,
69 ) -> Option<Box<dyn Action>>
70 + 'static,
71>;
72type AnyFocusListener = Box<dyn Fn(&FocusEvent, &mut WindowContext) + 'static>;
73
74slotmap::new_key_type! { pub struct FocusId; }
75
76/// A handle which can be used to track and manipulate the focused element in a window.
77pub struct FocusHandle {
78 pub(crate) id: FocusId,
79 handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
80}
81
82impl FocusHandle {
83 pub(crate) fn new(handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>) -> Self {
84 let id = handles.write().insert(AtomicUsize::new(1));
85 Self {
86 id,
87 handles: handles.clone(),
88 }
89 }
90
91 pub(crate) fn for_id(
92 id: FocusId,
93 handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
94 ) -> Option<Self> {
95 let lock = handles.read();
96 let ref_count = lock.get(id)?;
97 if ref_count.load(SeqCst) == 0 {
98 None
99 } else {
100 ref_count.fetch_add(1, SeqCst);
101 Some(Self {
102 id,
103 handles: handles.clone(),
104 })
105 }
106 }
107
108 /// Obtains whether the element associated with this handle is currently focused.
109 pub fn is_focused(&self, cx: &WindowContext) -> bool {
110 cx.window.focus == Some(self.id)
111 }
112
113 /// Obtains whether the element associated with this handle contains the focused
114 /// element or is itself focused.
115 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
116 cx.focused()
117 .map_or(false, |focused| self.contains(&focused, cx))
118 }
119
120 /// Obtains whether the element associated with this handle is contained within the
121 /// focused element or is itself focused.
122 pub fn within_focused(&self, cx: &WindowContext) -> bool {
123 let focused = cx.focused();
124 focused.map_or(false, |focused| focused.contains(self, cx))
125 }
126
127 /// Obtains whether this handle contains the given handle in the most recently rendered frame.
128 pub(crate) fn contains(&self, other: &Self, cx: &WindowContext) -> bool {
129 let mut ancestor = Some(other.id);
130 while let Some(ancestor_id) = ancestor {
131 if self.id == ancestor_id {
132 return true;
133 } else {
134 ancestor = cx.window.focus_parents_by_child.get(&ancestor_id).copied();
135 }
136 }
137 false
138 }
139}
140
141impl Clone for FocusHandle {
142 fn clone(&self) -> Self {
143 Self::for_id(self.id, &self.handles).unwrap()
144 }
145}
146
147impl PartialEq for FocusHandle {
148 fn eq(&self, other: &Self) -> bool {
149 self.id == other.id
150 }
151}
152
153impl Eq for FocusHandle {}
154
155impl Drop for FocusHandle {
156 fn drop(&mut self) {
157 self.handles
158 .read()
159 .get(self.id)
160 .unwrap()
161 .fetch_sub(1, SeqCst);
162 }
163}
164
165// Holds the state for a specific window.
166pub struct Window {
167 pub(crate) handle: AnyWindowHandle,
168 pub(crate) removed: bool,
169 platform_window: Box<dyn PlatformWindow>,
170 display_id: DisplayId,
171 sprite_atlas: Arc<dyn PlatformAtlas>,
172 rem_size: Pixels,
173 content_size: Size<Pixels>,
174 pub(crate) layout_engine: TaffyLayoutEngine,
175 pub(crate) root_view: Option<AnyView>,
176 pub(crate) element_id_stack: GlobalElementId,
177 prev_frame_element_states: HashMap<GlobalElementId, AnyBox>,
178 element_states: HashMap<GlobalElementId, AnyBox>,
179 prev_frame_key_matchers: HashMap<GlobalElementId, KeyMatcher>,
180 key_matchers: HashMap<GlobalElementId, KeyMatcher>,
181 z_index_stack: StackingOrder,
182 content_mask_stack: Vec<ContentMask<Pixels>>,
183 element_offset_stack: Vec<Point<Pixels>>,
184 mouse_listeners: HashMap<TypeId, Vec<(StackingOrder, AnyListener)>>,
185 key_dispatch_stack: Vec<KeyDispatchStackFrame>,
186 freeze_key_dispatch_stack: bool,
187 focus_stack: Vec<FocusId>,
188 focus_parents_by_child: HashMap<FocusId, FocusId>,
189 pub(crate) focus_listeners: Vec<AnyFocusListener>,
190 pub(crate) focus_handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
191 default_prevented: bool,
192 mouse_position: Point<Pixels>,
193 requested_cursor_style: Option<CursorStyle>,
194 scale_factor: f32,
195 bounds: WindowBounds,
196 bounds_observers: SubscriberSet<(), AnyObserver>,
197 active: bool,
198 activation_observers: SubscriberSet<(), AnyObserver>,
199 pub(crate) scene_builder: SceneBuilder,
200 pub(crate) dirty: bool,
201 pub(crate) last_blur: Option<Option<FocusId>>,
202 pub(crate) focus: Option<FocusId>,
203}
204
205impl Window {
206 pub(crate) fn new(
207 handle: AnyWindowHandle,
208 options: WindowOptions,
209 cx: &mut AppContext,
210 ) -> Self {
211 let platform_window = cx.platform.open_window(handle, options);
212 let display_id = platform_window.display().id();
213 let sprite_atlas = platform_window.sprite_atlas();
214 let mouse_position = platform_window.mouse_position();
215 let content_size = platform_window.content_size();
216 let scale_factor = platform_window.scale_factor();
217 let bounds = platform_window.bounds();
218
219 platform_window.on_resize(Box::new({
220 let mut cx = cx.to_async();
221 move |_, _| {
222 handle
223 .update(&mut cx, |_, cx| cx.window_bounds_changed())
224 .log_err();
225 }
226 }));
227 platform_window.on_moved(Box::new({
228 let mut cx = cx.to_async();
229 move || {
230 handle
231 .update(&mut cx, |_, cx| cx.window_bounds_changed())
232 .log_err();
233 }
234 }));
235 platform_window.on_active_status_change(Box::new({
236 let mut cx = cx.to_async();
237 move |active| {
238 handle
239 .update(&mut cx, |_, cx| {
240 cx.window.active = active;
241 cx.window
242 .activation_observers
243 .clone()
244 .retain(&(), |callback| callback(cx));
245 })
246 .log_err();
247 }
248 }));
249
250 platform_window.on_input({
251 let mut cx = cx.to_async();
252 Box::new(move |event| {
253 handle
254 .update(&mut cx, |_, cx| cx.dispatch_event(event))
255 .log_err()
256 .unwrap_or(true)
257 })
258 });
259
260 Window {
261 handle,
262 removed: false,
263 platform_window,
264 display_id,
265 sprite_atlas,
266 rem_size: px(16.),
267 content_size,
268 layout_engine: TaffyLayoutEngine::new(),
269 root_view: None,
270 element_id_stack: GlobalElementId::default(),
271 prev_frame_element_states: HashMap::default(),
272 element_states: HashMap::default(),
273 prev_frame_key_matchers: HashMap::default(),
274 key_matchers: HashMap::default(),
275 z_index_stack: StackingOrder(SmallVec::new()),
276 content_mask_stack: Vec::new(),
277 element_offset_stack: Vec::new(),
278 mouse_listeners: HashMap::default(),
279 key_dispatch_stack: Vec::new(),
280 freeze_key_dispatch_stack: false,
281 focus_stack: Vec::new(),
282 focus_parents_by_child: HashMap::default(),
283 focus_listeners: Vec::new(),
284 focus_handles: Arc::new(RwLock::new(SlotMap::with_key())),
285 default_prevented: true,
286 mouse_position,
287 requested_cursor_style: None,
288 scale_factor,
289 bounds,
290 bounds_observers: SubscriberSet::new(),
291 active: false,
292 activation_observers: SubscriberSet::new(),
293 scene_builder: SceneBuilder::new(),
294 dirty: true,
295 last_blur: None,
296 focus: None,
297 }
298 }
299}
300
301/// When constructing the element tree, we maintain a stack of key dispatch frames until we
302/// find the focused element. We interleave key listeners with dispatch contexts so we can use the
303/// contexts when matching key events against the keymap.
304enum KeyDispatchStackFrame {
305 Listener {
306 event_type: TypeId,
307 listener: AnyKeyListener,
308 },
309 Context(DispatchContext),
310}
311
312/// Indicates which region of the window is visible. Content falling outside of this mask will not be
313/// rendered. Currently, only rectangular content masks are supported, but we give the mask its own type
314/// to leave room to support more complex shapes in the future.
315#[derive(Clone, Debug, Default, PartialEq, Eq)]
316#[repr(C)]
317pub struct ContentMask<P: Clone + Default + Debug> {
318 pub bounds: Bounds<P>,
319}
320
321impl ContentMask<Pixels> {
322 /// Scale the content mask's pixel units by the given scaling factor.
323 pub fn scale(&self, factor: f32) -> ContentMask<ScaledPixels> {
324 ContentMask {
325 bounds: self.bounds.scale(factor),
326 }
327 }
328
329 /// Intersect the content mask with the given content mask.
330 pub fn intersect(&self, other: &Self) -> Self {
331 let bounds = self.bounds.intersect(&other.bounds);
332 ContentMask { bounds }
333 }
334}
335
336/// Provides access to application state in the context of a single window. Derefs
337/// to an `AppContext`, so you can also pass a `WindowContext` to any method that takes
338/// an `AppContext` and call any `AppContext` methods.
339pub struct WindowContext<'a> {
340 pub(crate) app: &'a mut AppContext,
341 pub(crate) window: &'a mut Window,
342}
343
344impl<'a> WindowContext<'a> {
345 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window) -> Self {
346 Self { app, window }
347 }
348
349 /// Obtain a handle to the window that belongs to this context.
350 pub fn window_handle(&self) -> AnyWindowHandle {
351 self.window.handle
352 }
353
354 /// Mark the window as dirty, scheduling it to be redrawn on the next frame.
355 pub fn notify(&mut self) {
356 self.window.dirty = true;
357 }
358
359 /// Close this window.
360 pub fn remove_window(&mut self) {
361 self.window.removed = true;
362 }
363
364 /// Obtain a new `FocusHandle`, which allows you to track and manipulate the keyboard focus
365 /// for elements rendered within this window.
366 pub fn focus_handle(&mut self) -> FocusHandle {
367 FocusHandle::new(&self.window.focus_handles)
368 }
369
370 /// Obtain the currently focused `FocusHandle`. If no elements are focused, returns `None`.
371 pub fn focused(&self) -> Option<FocusHandle> {
372 self.window
373 .focus
374 .and_then(|id| FocusHandle::for_id(id, &self.window.focus_handles))
375 }
376
377 /// Move focus to the element associated with the given `FocusHandle`.
378 pub fn focus(&mut self, handle: &FocusHandle) {
379 if self.window.last_blur.is_none() {
380 self.window.last_blur = Some(self.window.focus);
381 }
382
383 self.window.focus = Some(handle.id);
384 self.app.push_effect(Effect::FocusChanged {
385 window_handle: self.window.handle,
386 focused: Some(handle.id),
387 });
388 self.notify();
389 }
390
391 /// Remove focus from all elements within this context's window.
392 pub fn blur(&mut self) {
393 if self.window.last_blur.is_none() {
394 self.window.last_blur = Some(self.window.focus);
395 }
396
397 self.window.focus = None;
398 self.app.push_effect(Effect::FocusChanged {
399 window_handle: self.window.handle,
400 focused: None,
401 });
402 self.notify();
403 }
404
405 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
406 /// that are currently on the stack to be returned to the app.
407 pub fn defer(&mut self, f: impl FnOnce(&mut WindowContext) + 'static) {
408 let handle = self.window.handle;
409 self.app.defer(move |cx| {
410 handle.update(cx, |_, cx| f(cx)).ok();
411 });
412 }
413
414 pub fn subscribe<Emitter, E>(
415 &mut self,
416 entity: &E,
417 mut on_event: impl FnMut(E, &Emitter::Event, &mut WindowContext<'_>) + 'static,
418 ) -> Subscription
419 where
420 Emitter: EventEmitter,
421 E: Entity<Emitter>,
422 {
423 let entity_id = entity.entity_id();
424 let entity = entity.downgrade();
425 let window_handle = self.window.handle;
426 self.app.event_listeners.insert(
427 entity_id,
428 Box::new(move |event, cx| {
429 window_handle
430 .update(cx, |_, cx| {
431 if let Some(handle) = E::upgrade_from(&entity) {
432 let event = event.downcast_ref().expect("invalid event type");
433 on_event(handle, event, cx);
434 true
435 } else {
436 false
437 }
438 })
439 .unwrap_or(false)
440 }),
441 )
442 }
443
444 /// Create an `AsyncWindowContext`, which has a static lifetime and can be held across
445 /// await points in async code.
446 pub fn to_async(&self) -> AsyncWindowContext {
447 AsyncWindowContext::new(self.app.to_async(), self.window.handle)
448 }
449
450 /// Schedule the given closure to be run directly after the current frame is rendered.
451 pub fn on_next_frame(&mut self, callback: impl FnOnce(&mut WindowContext) + 'static) {
452 let handle = self.window.handle;
453 let display_id = self.window.display_id;
454
455 if !self.frame_consumers.contains_key(&display_id) {
456 let (tx, mut rx) = mpsc::unbounded::<()>();
457 self.platform.set_display_link_output_callback(
458 display_id,
459 Box::new(move |_current_time, _output_time| _ = tx.unbounded_send(())),
460 );
461
462 let consumer_task = self.app.spawn(|cx| async move {
463 while rx.next().await.is_some() {
464 cx.update(|cx| {
465 for callback in cx
466 .next_frame_callbacks
467 .get_mut(&display_id)
468 .unwrap()
469 .drain(..)
470 .collect::<SmallVec<[_; 32]>>()
471 {
472 callback(cx);
473 }
474 })
475 .ok();
476
477 // Flush effects, then stop the display link if no new next_frame_callbacks have been added.
478
479 cx.update(|cx| {
480 if cx.next_frame_callbacks.is_empty() {
481 cx.platform.stop_display_link(display_id);
482 }
483 })
484 .ok();
485 }
486 });
487 self.frame_consumers.insert(display_id, consumer_task);
488 }
489
490 if self.next_frame_callbacks.is_empty() {
491 self.platform.start_display_link(display_id);
492 }
493
494 self.next_frame_callbacks
495 .entry(display_id)
496 .or_default()
497 .push(Box::new(move |cx: &mut AppContext| {
498 cx.update_window(handle, |_root_view, cx| callback(cx)).ok();
499 }));
500 }
501
502 /// Spawn the future returned by the given closure on the application thread pool.
503 /// The closure is provided a handle to the current window and an `AsyncWindowContext` for
504 /// use within your future.
505 pub fn spawn<Fut, R>(&mut self, f: impl FnOnce(AsyncWindowContext) -> Fut) -> Task<R>
506 where
507 R: 'static,
508 Fut: Future<Output = R> + 'static,
509 {
510 self.app
511 .spawn(|app| f(AsyncWindowContext::new(app, self.window.handle)))
512 }
513
514 /// Update the global of the given type. The given closure is given simultaneous mutable
515 /// access both to the global and the context.
516 pub fn update_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
517 where
518 G: 'static,
519 {
520 let mut global = self.app.lease_global::<G>();
521 let result = f(&mut global, self);
522 self.app.end_global_lease(global);
523 result
524 }
525
526 /// Add a node to the layout tree for the current frame. Takes the `Style` of the element for which
527 /// layout is being requested, along with the layout ids of any children. This method is called during
528 /// calls to the `Element::layout` trait method and enables any element to participate in layout.
529 pub fn request_layout(
530 &mut self,
531 style: &Style,
532 children: impl IntoIterator<Item = LayoutId>,
533 ) -> LayoutId {
534 self.app.layout_id_buffer.clear();
535 self.app.layout_id_buffer.extend(children.into_iter());
536 let rem_size = self.rem_size();
537
538 self.window
539 .layout_engine
540 .request_layout(style, rem_size, &self.app.layout_id_buffer)
541 }
542
543 /// Add a node to the layout tree for the current frame. Instead of taking a `Style` and children,
544 /// this variant takes a function that is invoked during layout so you can use arbitrary logic to
545 /// determine the element's size. One place this is used internally is when measuring text.
546 ///
547 /// The given closure is invoked at layout time with the known dimensions and available space and
548 /// returns a `Size`.
549 pub fn request_measured_layout<
550 F: Fn(Size<Option<Pixels>>, Size<AvailableSpace>) -> Size<Pixels> + Send + Sync + 'static,
551 >(
552 &mut self,
553 style: Style,
554 rem_size: Pixels,
555 measure: F,
556 ) -> LayoutId {
557 self.window
558 .layout_engine
559 .request_measured_layout(style, rem_size, measure)
560 }
561
562 /// Obtain the bounds computed for the given LayoutId relative to the window. This method should not
563 /// be invoked until the paint phase begins, and will usually be invoked by GPUI itself automatically
564 /// in order to pass your element its `Bounds` automatically.
565 pub fn layout_bounds(&mut self, layout_id: LayoutId) -> Bounds<Pixels> {
566 let mut bounds = self
567 .window
568 .layout_engine
569 .layout_bounds(layout_id)
570 .map(Into::into);
571 bounds.origin += self.element_offset();
572 bounds
573 }
574
575 fn window_bounds_changed(&mut self) {
576 self.window.scale_factor = self.window.platform_window.scale_factor();
577 self.window.content_size = self.window.platform_window.content_size();
578 self.window.bounds = self.window.platform_window.bounds();
579 self.window.display_id = self.window.platform_window.display().id();
580 self.window.dirty = true;
581
582 self.window
583 .bounds_observers
584 .clone()
585 .retain(&(), |callback| callback(self));
586 }
587
588 pub fn window_bounds(&self) -> WindowBounds {
589 self.window.bounds
590 }
591
592 pub fn is_window_active(&self) -> bool {
593 self.window.active
594 }
595
596 pub fn zoom_window(&self) {
597 self.window.platform_window.zoom();
598 }
599
600 pub fn display(&self) -> Option<Rc<dyn PlatformDisplay>> {
601 self.platform
602 .displays()
603 .into_iter()
604 .find(|display| display.id() == self.window.display_id)
605 }
606
607 /// The scale factor of the display associated with the window. For example, it could
608 /// return 2.0 for a "retina" display, indicating that each logical pixel should actually
609 /// be rendered as two pixels on screen.
610 pub fn scale_factor(&self) -> f32 {
611 self.window.scale_factor
612 }
613
614 /// The size of an em for the base font of the application. Adjusting this value allows the
615 /// UI to scale, just like zooming a web page.
616 pub fn rem_size(&self) -> Pixels {
617 self.window.rem_size
618 }
619
620 /// Sets the size of an em for the base font of the application. Adjusting this value allows the
621 /// UI to scale, just like zooming a web page.
622 pub fn set_rem_size(&mut self, rem_size: impl Into<Pixels>) {
623 self.window.rem_size = rem_size.into();
624 }
625
626 /// The line height associated with the current text style.
627 pub fn line_height(&self) -> Pixels {
628 let rem_size = self.rem_size();
629 let text_style = self.text_style();
630 text_style
631 .line_height
632 .to_pixels(text_style.font_size.into(), rem_size)
633 }
634
635 /// Call to prevent the default action of an event. Currently only used to prevent
636 /// parent elements from becoming focused on mouse down.
637 pub fn prevent_default(&mut self) {
638 self.window.default_prevented = true;
639 }
640
641 /// Obtain whether default has been prevented for the event currently being dispatched.
642 pub fn default_prevented(&self) -> bool {
643 self.window.default_prevented
644 }
645
646 /// Register a mouse event listener on the window for the current frame. The type of event
647 /// is determined by the first parameter of the given listener. When the next frame is rendered
648 /// the listener will be cleared.
649 ///
650 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
651 /// a specific need to register a global listener.
652 pub fn on_mouse_event<Event: 'static>(
653 &mut self,
654 handler: impl Fn(&Event, DispatchPhase, &mut WindowContext) + 'static,
655 ) {
656 let order = self.window.z_index_stack.clone();
657 self.window
658 .mouse_listeners
659 .entry(TypeId::of::<Event>())
660 .or_default()
661 .push((
662 order,
663 Box::new(move |event: &dyn Any, phase, cx| {
664 handler(event.downcast_ref().unwrap(), phase, cx)
665 }),
666 ))
667 }
668
669 /// The position of the mouse relative to the window.
670 pub fn mouse_position(&self) -> Point<Pixels> {
671 self.window.mouse_position
672 }
673
674 pub fn set_cursor_style(&mut self, style: CursorStyle) {
675 self.window.requested_cursor_style = Some(style)
676 }
677
678 /// Called during painting to invoke the given closure in a new stacking context. The given
679 /// z-index is interpreted relative to the previous call to `stack`.
680 pub fn stack<R>(&mut self, z_index: u32, f: impl FnOnce(&mut Self) -> R) -> R {
681 self.window.z_index_stack.push(z_index);
682 let result = f(self);
683 self.window.z_index_stack.pop();
684 result
685 }
686
687 /// Paint one or more drop shadows into the scene for the current frame at the current z-index.
688 pub fn paint_shadows(
689 &mut self,
690 bounds: Bounds<Pixels>,
691 corner_radii: Corners<Pixels>,
692 shadows: &[BoxShadow],
693 ) {
694 let scale_factor = self.scale_factor();
695 let content_mask = self.content_mask();
696 let window = &mut *self.window;
697 for shadow in shadows {
698 let mut shadow_bounds = bounds;
699 shadow_bounds.origin += shadow.offset;
700 shadow_bounds.dilate(shadow.spread_radius);
701 window.scene_builder.insert(
702 &window.z_index_stack,
703 Shadow {
704 order: 0,
705 bounds: shadow_bounds.scale(scale_factor),
706 content_mask: content_mask.scale(scale_factor),
707 corner_radii: corner_radii.scale(scale_factor),
708 color: shadow.color,
709 blur_radius: shadow.blur_radius.scale(scale_factor),
710 },
711 );
712 }
713 }
714
715 /// Paint one or more quads into the scene for the current frame at the current stacking context.
716 /// Quads are colored rectangular regions with an optional background, border, and corner radius.
717 pub fn paint_quad(
718 &mut self,
719 bounds: Bounds<Pixels>,
720 corner_radii: Corners<Pixels>,
721 background: impl Into<Hsla>,
722 border_widths: Edges<Pixels>,
723 border_color: impl Into<Hsla>,
724 ) {
725 let scale_factor = self.scale_factor();
726 let content_mask = self.content_mask();
727
728 let window = &mut *self.window;
729 window.scene_builder.insert(
730 &window.z_index_stack,
731 Quad {
732 order: 0,
733 bounds: bounds.scale(scale_factor),
734 content_mask: content_mask.scale(scale_factor),
735 background: background.into(),
736 border_color: border_color.into(),
737 corner_radii: corner_radii.scale(scale_factor),
738 border_widths: border_widths.scale(scale_factor),
739 },
740 );
741 }
742
743 /// Paint the given `Path` into the scene for the current frame at the current z-index.
744 pub fn paint_path(&mut self, mut path: Path<Pixels>, color: impl Into<Hsla>) {
745 let scale_factor = self.scale_factor();
746 let content_mask = self.content_mask();
747 path.content_mask = content_mask;
748 path.color = color.into();
749 let window = &mut *self.window;
750 window
751 .scene_builder
752 .insert(&window.z_index_stack, path.scale(scale_factor));
753 }
754
755 /// Paint an underline into the scene for the current frame at the current z-index.
756 pub fn paint_underline(
757 &mut self,
758 origin: Point<Pixels>,
759 width: Pixels,
760 style: &UnderlineStyle,
761 ) -> Result<()> {
762 let scale_factor = self.scale_factor();
763 let height = if style.wavy {
764 style.thickness * 3.
765 } else {
766 style.thickness
767 };
768 let bounds = Bounds {
769 origin,
770 size: size(width, height),
771 };
772 let content_mask = self.content_mask();
773 let window = &mut *self.window;
774 window.scene_builder.insert(
775 &window.z_index_stack,
776 Underline {
777 order: 0,
778 bounds: bounds.scale(scale_factor),
779 content_mask: content_mask.scale(scale_factor),
780 thickness: style.thickness.scale(scale_factor),
781 color: style.color.unwrap_or_default(),
782 wavy: style.wavy,
783 },
784 );
785 Ok(())
786 }
787
788 /// Paint a monochrome (non-emoji) glyph into the scene for the current frame at the current z-index.
789 pub fn paint_glyph(
790 &mut self,
791 origin: Point<Pixels>,
792 font_id: FontId,
793 glyph_id: GlyphId,
794 font_size: Pixels,
795 color: Hsla,
796 ) -> Result<()> {
797 let scale_factor = self.scale_factor();
798 let glyph_origin = origin.scale(scale_factor);
799 let subpixel_variant = Point {
800 x: (glyph_origin.x.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
801 y: (glyph_origin.y.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
802 };
803 let params = RenderGlyphParams {
804 font_id,
805 glyph_id,
806 font_size,
807 subpixel_variant,
808 scale_factor,
809 is_emoji: false,
810 };
811
812 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
813 if !raster_bounds.is_zero() {
814 let tile =
815 self.window
816 .sprite_atlas
817 .get_or_insert_with(¶ms.clone().into(), &mut || {
818 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
819 Ok((size, Cow::Owned(bytes)))
820 })?;
821 let bounds = Bounds {
822 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
823 size: tile.bounds.size.map(Into::into),
824 };
825 let content_mask = self.content_mask().scale(scale_factor);
826 let window = &mut *self.window;
827 window.scene_builder.insert(
828 &window.z_index_stack,
829 MonochromeSprite {
830 order: 0,
831 bounds,
832 content_mask,
833 color,
834 tile,
835 },
836 );
837 }
838 Ok(())
839 }
840
841 /// Paint an emoji glyph into the scene for the current frame at the current z-index.
842 pub fn paint_emoji(
843 &mut self,
844 origin: Point<Pixels>,
845 font_id: FontId,
846 glyph_id: GlyphId,
847 font_size: Pixels,
848 ) -> Result<()> {
849 let scale_factor = self.scale_factor();
850 let glyph_origin = origin.scale(scale_factor);
851 let params = RenderGlyphParams {
852 font_id,
853 glyph_id,
854 font_size,
855 // We don't render emojis with subpixel variants.
856 subpixel_variant: Default::default(),
857 scale_factor,
858 is_emoji: true,
859 };
860
861 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
862 if !raster_bounds.is_zero() {
863 let tile =
864 self.window
865 .sprite_atlas
866 .get_or_insert_with(¶ms.clone().into(), &mut || {
867 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
868 Ok((size, Cow::Owned(bytes)))
869 })?;
870 let bounds = Bounds {
871 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
872 size: tile.bounds.size.map(Into::into),
873 };
874 let content_mask = self.content_mask().scale(scale_factor);
875 let window = &mut *self.window;
876
877 window.scene_builder.insert(
878 &window.z_index_stack,
879 PolychromeSprite {
880 order: 0,
881 bounds,
882 corner_radii: Default::default(),
883 content_mask,
884 tile,
885 grayscale: false,
886 },
887 );
888 }
889 Ok(())
890 }
891
892 /// Paint a monochrome SVG into the scene for the current frame at the current stacking context.
893 pub fn paint_svg(
894 &mut self,
895 bounds: Bounds<Pixels>,
896 path: SharedString,
897 color: Hsla,
898 ) -> Result<()> {
899 let scale_factor = self.scale_factor();
900 let bounds = bounds.scale(scale_factor);
901 // Render the SVG at twice the size to get a higher quality result.
902 let params = RenderSvgParams {
903 path,
904 size: bounds
905 .size
906 .map(|pixels| DevicePixels::from((pixels.0 * 2.).ceil() as i32)),
907 };
908
909 let tile =
910 self.window
911 .sprite_atlas
912 .get_or_insert_with(¶ms.clone().into(), &mut || {
913 let bytes = self.svg_renderer.render(¶ms)?;
914 Ok((params.size, Cow::Owned(bytes)))
915 })?;
916 let content_mask = self.content_mask().scale(scale_factor);
917
918 let window = &mut *self.window;
919 window.scene_builder.insert(
920 &window.z_index_stack,
921 MonochromeSprite {
922 order: 0,
923 bounds,
924 content_mask,
925 color,
926 tile,
927 },
928 );
929
930 Ok(())
931 }
932
933 /// Paint an image into the scene for the current frame at the current z-index.
934 pub fn paint_image(
935 &mut self,
936 bounds: Bounds<Pixels>,
937 corner_radii: Corners<Pixels>,
938 data: Arc<ImageData>,
939 grayscale: bool,
940 ) -> Result<()> {
941 let scale_factor = self.scale_factor();
942 let bounds = bounds.scale(scale_factor);
943 let params = RenderImageParams { image_id: data.id };
944
945 let tile = self
946 .window
947 .sprite_atlas
948 .get_or_insert_with(¶ms.clone().into(), &mut || {
949 Ok((data.size(), Cow::Borrowed(data.as_bytes())))
950 })?;
951 let content_mask = self.content_mask().scale(scale_factor);
952 let corner_radii = corner_radii.scale(scale_factor);
953
954 let window = &mut *self.window;
955 window.scene_builder.insert(
956 &window.z_index_stack,
957 PolychromeSprite {
958 order: 0,
959 bounds,
960 content_mask,
961 corner_radii,
962 tile,
963 grayscale,
964 },
965 );
966 Ok(())
967 }
968
969 /// Draw pixels to the display for this window based on the contents of its scene.
970 pub(crate) fn draw(&mut self) {
971 let root_view = self.window.root_view.take().unwrap();
972
973 self.start_frame();
974
975 self.stack(0, |cx| {
976 let available_space = cx.window.content_size.map(Into::into);
977 root_view.draw(available_space, cx);
978 });
979
980 if let Some(active_drag) = self.app.active_drag.take() {
981 self.stack(1, |cx| {
982 let offset = cx.mouse_position() - active_drag.cursor_offset;
983 cx.with_element_offset(Some(offset), |cx| {
984 let available_space =
985 size(AvailableSpace::MinContent, AvailableSpace::MinContent);
986 active_drag.view.draw(available_space, cx);
987 cx.active_drag = Some(active_drag);
988 });
989 });
990 }
991
992 self.window.root_view = Some(root_view);
993 let scene = self.window.scene_builder.build();
994
995 self.window.platform_window.draw(scene);
996 let cursor_style = self
997 .window
998 .requested_cursor_style
999 .take()
1000 .unwrap_or(CursorStyle::Arrow);
1001 self.platform.set_cursor_style(cursor_style);
1002
1003 self.window.dirty = false;
1004 }
1005
1006 fn start_frame(&mut self) {
1007 self.text_system().start_frame();
1008
1009 let window = &mut *self.window;
1010
1011 // Move the current frame element states to the previous frame.
1012 // The new empty element states map will be populated for any element states we
1013 // reference during the upcoming frame.
1014 mem::swap(
1015 &mut window.element_states,
1016 &mut window.prev_frame_element_states,
1017 );
1018 window.element_states.clear();
1019
1020 // Make the current key matchers the previous, and then clear the current.
1021 // An empty key matcher map will be created for every identified element in the
1022 // upcoming frame.
1023 mem::swap(
1024 &mut window.key_matchers,
1025 &mut window.prev_frame_key_matchers,
1026 );
1027 window.key_matchers.clear();
1028
1029 // Clear mouse event listeners, because elements add new element listeners
1030 // when the upcoming frame is painted.
1031 window.mouse_listeners.values_mut().for_each(Vec::clear);
1032
1033 // Clear focus state, because we determine what is focused when the new elements
1034 // in the upcoming frame are initialized.
1035 window.focus_listeners.clear();
1036 window.key_dispatch_stack.clear();
1037 window.focus_parents_by_child.clear();
1038 window.freeze_key_dispatch_stack = false;
1039 }
1040
1041 /// Dispatch a mouse or keyboard event on the window.
1042 fn dispatch_event(&mut self, event: InputEvent) -> bool {
1043 let event = match event {
1044 // Track the mouse position with our own state, since accessing the platform
1045 // API for the mouse position can only occur on the main thread.
1046 InputEvent::MouseMove(mouse_move) => {
1047 self.window.mouse_position = mouse_move.position;
1048 InputEvent::MouseMove(mouse_move)
1049 }
1050 // Translate dragging and dropping of external files from the operating system
1051 // to internal drag and drop events.
1052 InputEvent::FileDrop(file_drop) => match file_drop {
1053 FileDropEvent::Entered { position, files } => {
1054 self.window.mouse_position = position;
1055 if self.active_drag.is_none() {
1056 self.active_drag = Some(AnyDrag {
1057 view: self.build_view(|_| files).into(),
1058 cursor_offset: position,
1059 });
1060 }
1061 InputEvent::MouseDown(MouseDownEvent {
1062 position,
1063 button: MouseButton::Left,
1064 click_count: 1,
1065 modifiers: Modifiers::default(),
1066 })
1067 }
1068 FileDropEvent::Pending { position } => {
1069 self.window.mouse_position = position;
1070 InputEvent::MouseMove(MouseMoveEvent {
1071 position,
1072 pressed_button: Some(MouseButton::Left),
1073 modifiers: Modifiers::default(),
1074 })
1075 }
1076 FileDropEvent::Submit { position } => {
1077 self.window.mouse_position = position;
1078 InputEvent::MouseUp(MouseUpEvent {
1079 button: MouseButton::Left,
1080 position,
1081 modifiers: Modifiers::default(),
1082 click_count: 1,
1083 })
1084 }
1085 FileDropEvent::Exited => InputEvent::MouseUp(MouseUpEvent {
1086 button: MouseButton::Left,
1087 position: Point::default(),
1088 modifiers: Modifiers::default(),
1089 click_count: 1,
1090 }),
1091 },
1092 _ => event,
1093 };
1094
1095 if let Some(any_mouse_event) = event.mouse_event() {
1096 // Handlers may set this to false by calling `stop_propagation`
1097 self.app.propagate_event = true;
1098 self.window.default_prevented = false;
1099
1100 if let Some(mut handlers) = self
1101 .window
1102 .mouse_listeners
1103 .remove(&any_mouse_event.type_id())
1104 {
1105 // Because handlers may add other handlers, we sort every time.
1106 handlers.sort_by(|(a, _), (b, _)| a.cmp(b));
1107
1108 // Capture phase, events bubble from back to front. Handlers for this phase are used for
1109 // special purposes, such as detecting events outside of a given Bounds.
1110 for (_, handler) in &handlers {
1111 handler(any_mouse_event, DispatchPhase::Capture, self);
1112 if !self.app.propagate_event {
1113 break;
1114 }
1115 }
1116
1117 // Bubble phase, where most normal handlers do their work.
1118 if self.app.propagate_event {
1119 for (_, handler) in handlers.iter().rev() {
1120 handler(any_mouse_event, DispatchPhase::Bubble, self);
1121 if !self.app.propagate_event {
1122 break;
1123 }
1124 }
1125 }
1126
1127 if self.app.propagate_event
1128 && any_mouse_event.downcast_ref::<MouseUpEvent>().is_some()
1129 {
1130 self.active_drag = None;
1131 }
1132
1133 // Just in case any handlers added new handlers, which is weird, but possible.
1134 handlers.extend(
1135 self.window
1136 .mouse_listeners
1137 .get_mut(&any_mouse_event.type_id())
1138 .into_iter()
1139 .flat_map(|handlers| handlers.drain(..)),
1140 );
1141 self.window
1142 .mouse_listeners
1143 .insert(any_mouse_event.type_id(), handlers);
1144 }
1145 } else if let Some(any_key_event) = event.keyboard_event() {
1146 let key_dispatch_stack = mem::take(&mut self.window.key_dispatch_stack);
1147 let key_event_type = any_key_event.type_id();
1148 let mut context_stack = SmallVec::<[&DispatchContext; 16]>::new();
1149
1150 for (ix, frame) in key_dispatch_stack.iter().enumerate() {
1151 match frame {
1152 KeyDispatchStackFrame::Listener {
1153 event_type,
1154 listener,
1155 } => {
1156 if key_event_type == *event_type {
1157 if let Some(action) = listener(
1158 any_key_event,
1159 &context_stack,
1160 DispatchPhase::Capture,
1161 self,
1162 ) {
1163 self.dispatch_action(action, &key_dispatch_stack[..ix]);
1164 }
1165 if !self.app.propagate_event {
1166 break;
1167 }
1168 }
1169 }
1170 KeyDispatchStackFrame::Context(context) => {
1171 context_stack.push(&context);
1172 }
1173 }
1174 }
1175
1176 if self.app.propagate_event {
1177 for (ix, frame) in key_dispatch_stack.iter().enumerate().rev() {
1178 match frame {
1179 KeyDispatchStackFrame::Listener {
1180 event_type,
1181 listener,
1182 } => {
1183 if key_event_type == *event_type {
1184 if let Some(action) = listener(
1185 any_key_event,
1186 &context_stack,
1187 DispatchPhase::Bubble,
1188 self,
1189 ) {
1190 self.dispatch_action(action, &key_dispatch_stack[..ix]);
1191 }
1192
1193 if !self.app.propagate_event {
1194 break;
1195 }
1196 }
1197 }
1198 KeyDispatchStackFrame::Context(_) => {
1199 context_stack.pop();
1200 }
1201 }
1202 }
1203 }
1204
1205 drop(context_stack);
1206 self.window.key_dispatch_stack = key_dispatch_stack;
1207 }
1208
1209 true
1210 }
1211
1212 /// Attempt to map a keystroke to an action based on the keymap.
1213 pub fn match_keystroke(
1214 &mut self,
1215 element_id: &GlobalElementId,
1216 keystroke: &Keystroke,
1217 context_stack: &[&DispatchContext],
1218 ) -> KeyMatch {
1219 let key_match = self
1220 .window
1221 .key_matchers
1222 .get_mut(element_id)
1223 .unwrap()
1224 .match_keystroke(keystroke, context_stack);
1225
1226 if key_match.is_some() {
1227 for matcher in self.window.key_matchers.values_mut() {
1228 matcher.clear_pending();
1229 }
1230 }
1231
1232 key_match
1233 }
1234
1235 /// Register the given handler to be invoked whenever the global of the given type
1236 /// is updated.
1237 pub fn observe_global<G: 'static>(
1238 &mut self,
1239 f: impl Fn(&mut WindowContext<'_>) + 'static,
1240 ) -> Subscription {
1241 let window_handle = self.window.handle;
1242 self.global_observers.insert(
1243 TypeId::of::<G>(),
1244 Box::new(move |cx| window_handle.update(cx, |_, cx| f(cx)).is_ok()),
1245 )
1246 }
1247
1248 pub fn activate_window(&self) {
1249 self.window.platform_window.activate();
1250 }
1251
1252 pub fn prompt(
1253 &self,
1254 level: PromptLevel,
1255 msg: &str,
1256 answers: &[&str],
1257 ) -> oneshot::Receiver<usize> {
1258 self.window.platform_window.prompt(level, msg, answers)
1259 }
1260
1261 fn dispatch_action(
1262 &mut self,
1263 action: Box<dyn Action>,
1264 dispatch_stack: &[KeyDispatchStackFrame],
1265 ) {
1266 let action_type = action.as_any().type_id();
1267
1268 if let Some(mut global_listeners) = self.app.global_action_listeners.remove(&action_type) {
1269 for listener in &global_listeners {
1270 listener(action.as_ref(), DispatchPhase::Capture, self);
1271 if !self.app.propagate_event {
1272 break;
1273 }
1274 }
1275 global_listeners.extend(
1276 self.global_action_listeners
1277 .remove(&action_type)
1278 .unwrap_or_default(),
1279 );
1280 self.global_action_listeners
1281 .insert(action_type, global_listeners);
1282 }
1283
1284 if self.app.propagate_event {
1285 for stack_frame in dispatch_stack {
1286 if let KeyDispatchStackFrame::Listener {
1287 event_type,
1288 listener,
1289 } = stack_frame
1290 {
1291 if action_type == *event_type {
1292 listener(action.as_any(), &[], DispatchPhase::Capture, self);
1293 if !self.app.propagate_event {
1294 break;
1295 }
1296 }
1297 }
1298 }
1299 }
1300
1301 if self.app.propagate_event {
1302 for stack_frame in dispatch_stack.iter().rev() {
1303 if let KeyDispatchStackFrame::Listener {
1304 event_type,
1305 listener,
1306 } = stack_frame
1307 {
1308 if action_type == *event_type {
1309 listener(action.as_any(), &[], DispatchPhase::Bubble, self);
1310 if !self.app.propagate_event {
1311 break;
1312 }
1313 }
1314 }
1315 }
1316 }
1317
1318 if self.app.propagate_event {
1319 if let Some(mut global_listeners) =
1320 self.app.global_action_listeners.remove(&action_type)
1321 {
1322 for listener in global_listeners.iter().rev() {
1323 listener(action.as_ref(), DispatchPhase::Bubble, self);
1324 if !self.app.propagate_event {
1325 break;
1326 }
1327 }
1328 global_listeners.extend(
1329 self.global_action_listeners
1330 .remove(&action_type)
1331 .unwrap_or_default(),
1332 );
1333 self.global_action_listeners
1334 .insert(action_type, global_listeners);
1335 }
1336 }
1337 }
1338}
1339
1340impl Context for WindowContext<'_> {
1341 type Result<T> = T;
1342
1343 fn build_model<T>(
1344 &mut self,
1345 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
1346 ) -> Model<T>
1347 where
1348 T: 'static,
1349 {
1350 let slot = self.app.entities.reserve();
1351 let model = build_model(&mut ModelContext::new(&mut *self.app, slot.downgrade()));
1352 self.entities.insert(slot, model)
1353 }
1354
1355 fn update_model<T: 'static, R>(
1356 &mut self,
1357 model: &Model<T>,
1358 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
1359 ) -> R {
1360 let mut entity = self.entities.lease(model);
1361 let result = update(
1362 &mut *entity,
1363 &mut ModelContext::new(&mut *self.app, model.downgrade()),
1364 );
1365 self.entities.end_lease(entity);
1366 result
1367 }
1368
1369 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
1370 where
1371 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
1372 {
1373 if window == self.window.handle {
1374 let root_view = self.window.root_view.clone().unwrap();
1375 Ok(update(root_view, self))
1376 } else {
1377 window.update(self.app, update)
1378 }
1379 }
1380}
1381
1382impl VisualContext for WindowContext<'_> {
1383 fn build_view<V>(
1384 &mut self,
1385 build_view_state: impl FnOnce(&mut ViewContext<'_, V>) -> V,
1386 ) -> Self::Result<View<V>>
1387 where
1388 V: 'static,
1389 {
1390 let slot = self.app.entities.reserve();
1391 let view = View {
1392 model: slot.clone(),
1393 };
1394 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
1395 let entity = build_view_state(&mut cx);
1396 self.entities.insert(slot, entity);
1397 view
1398 }
1399
1400 /// Update the given view. Prefer calling `View::update` instead, which calls this method.
1401 fn update_view<T: 'static, R>(
1402 &mut self,
1403 view: &View<T>,
1404 update: impl FnOnce(&mut T, &mut ViewContext<'_, T>) -> R,
1405 ) -> Self::Result<R> {
1406 let mut lease = self.app.entities.lease(&view.model);
1407 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
1408 let result = update(&mut *lease, &mut cx);
1409 cx.app.entities.end_lease(lease);
1410 result
1411 }
1412
1413 fn replace_root_view<V>(
1414 &mut self,
1415 build_view: impl FnOnce(&mut ViewContext<'_, V>) -> V,
1416 ) -> Self::Result<View<V>>
1417 where
1418 V: Render,
1419 {
1420 let slot = self.app.entities.reserve();
1421 let view = View {
1422 model: slot.clone(),
1423 };
1424 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
1425 let entity = build_view(&mut cx);
1426 self.entities.insert(slot, entity);
1427 self.window.root_view = Some(view.clone().into());
1428 view
1429 }
1430}
1431
1432impl<'a> std::ops::Deref for WindowContext<'a> {
1433 type Target = AppContext;
1434
1435 fn deref(&self) -> &Self::Target {
1436 &self.app
1437 }
1438}
1439
1440impl<'a> std::ops::DerefMut for WindowContext<'a> {
1441 fn deref_mut(&mut self) -> &mut Self::Target {
1442 &mut self.app
1443 }
1444}
1445
1446impl<'a> Borrow<AppContext> for WindowContext<'a> {
1447 fn borrow(&self) -> &AppContext {
1448 &self.app
1449 }
1450}
1451
1452impl<'a> BorrowMut<AppContext> for WindowContext<'a> {
1453 fn borrow_mut(&mut self) -> &mut AppContext {
1454 &mut self.app
1455 }
1456}
1457
1458pub trait BorrowWindow: BorrowMut<Window> + BorrowMut<AppContext> {
1459 fn app_mut(&mut self) -> &mut AppContext {
1460 self.borrow_mut()
1461 }
1462
1463 fn window(&self) -> &Window {
1464 self.borrow()
1465 }
1466
1467 fn window_mut(&mut self) -> &mut Window {
1468 self.borrow_mut()
1469 }
1470
1471 /// Pushes the given element id onto the global stack and invokes the given closure
1472 /// with a `GlobalElementId`, which disambiguates the given id in the context of its ancestor
1473 /// ids. Because elements are discarded and recreated on each frame, the `GlobalElementId` is
1474 /// used to associate state with identified elements across separate frames.
1475 fn with_element_id<R>(
1476 &mut self,
1477 id: impl Into<ElementId>,
1478 f: impl FnOnce(GlobalElementId, &mut Self) -> R,
1479 ) -> R {
1480 let keymap = self.app_mut().keymap.clone();
1481 let window = self.window_mut();
1482 window.element_id_stack.push(id.into());
1483 let global_id = window.element_id_stack.clone();
1484
1485 if window.key_matchers.get(&global_id).is_none() {
1486 window.key_matchers.insert(
1487 global_id.clone(),
1488 window
1489 .prev_frame_key_matchers
1490 .remove(&global_id)
1491 .unwrap_or_else(|| KeyMatcher::new(keymap)),
1492 );
1493 }
1494
1495 let result = f(global_id, self);
1496 let window: &mut Window = self.borrow_mut();
1497 window.element_id_stack.pop();
1498 result
1499 }
1500
1501 /// Invoke the given function with the given content mask after intersecting it
1502 /// with the current mask.
1503 fn with_content_mask<R>(
1504 &mut self,
1505 mask: ContentMask<Pixels>,
1506 f: impl FnOnce(&mut Self) -> R,
1507 ) -> R {
1508 let mask = mask.intersect(&self.content_mask());
1509 self.window_mut().content_mask_stack.push(mask);
1510 let result = f(self);
1511 self.window_mut().content_mask_stack.pop();
1512 result
1513 }
1514
1515 /// Update the global element offset based on the given offset. This is used to implement
1516 /// scrolling and position drag handles.
1517 fn with_element_offset<R>(
1518 &mut self,
1519 offset: Option<Point<Pixels>>,
1520 f: impl FnOnce(&mut Self) -> R,
1521 ) -> R {
1522 let Some(offset) = offset else {
1523 return f(self);
1524 };
1525
1526 let offset = self.element_offset() + offset;
1527 self.window_mut().element_offset_stack.push(offset);
1528 let result = f(self);
1529 self.window_mut().element_offset_stack.pop();
1530 result
1531 }
1532
1533 /// Obtain the current element offset.
1534 fn element_offset(&self) -> Point<Pixels> {
1535 self.window()
1536 .element_offset_stack
1537 .last()
1538 .copied()
1539 .unwrap_or_default()
1540 }
1541
1542 /// Update or intialize state for an element with the given id that lives across multiple
1543 /// frames. If an element with this id existed in the previous frame, its state will be passed
1544 /// to the given closure. The state returned by the closure will be stored so it can be referenced
1545 /// when drawing the next frame.
1546 fn with_element_state<S, R>(
1547 &mut self,
1548 id: ElementId,
1549 f: impl FnOnce(Option<S>, &mut Self) -> (R, S),
1550 ) -> R
1551 where
1552 S: 'static,
1553 {
1554 self.with_element_id(id, |global_id, cx| {
1555 if let Some(any) = cx
1556 .window_mut()
1557 .element_states
1558 .remove(&global_id)
1559 .or_else(|| cx.window_mut().prev_frame_element_states.remove(&global_id))
1560 {
1561 // Using the extra inner option to avoid needing to reallocate a new box.
1562 let mut state_box = any
1563 .downcast::<Option<S>>()
1564 .expect("invalid element state type for id");
1565 let state = state_box
1566 .take()
1567 .expect("element state is already on the stack");
1568 let (result, state) = f(Some(state), cx);
1569 state_box.replace(state);
1570 cx.window_mut().element_states.insert(global_id, state_box);
1571 result
1572 } else {
1573 let (result, state) = f(None, cx);
1574 cx.window_mut()
1575 .element_states
1576 .insert(global_id, Box::new(Some(state)));
1577 result
1578 }
1579 })
1580 }
1581
1582 /// Like `with_element_state`, but for situations where the element_id is optional. If the
1583 /// id is `None`, no state will be retrieved or stored.
1584 fn with_optional_element_state<S, R>(
1585 &mut self,
1586 element_id: Option<ElementId>,
1587 f: impl FnOnce(Option<S>, &mut Self) -> (R, S),
1588 ) -> R
1589 where
1590 S: 'static,
1591 {
1592 if let Some(element_id) = element_id {
1593 self.with_element_state(element_id, f)
1594 } else {
1595 f(None, self).0
1596 }
1597 }
1598
1599 /// Obtain the current content mask.
1600 fn content_mask(&self) -> ContentMask<Pixels> {
1601 self.window()
1602 .content_mask_stack
1603 .last()
1604 .cloned()
1605 .unwrap_or_else(|| ContentMask {
1606 bounds: Bounds {
1607 origin: Point::default(),
1608 size: self.window().content_size,
1609 },
1610 })
1611 }
1612
1613 /// The size of an em for the base font of the application. Adjusting this value allows the
1614 /// UI to scale, just like zooming a web page.
1615 fn rem_size(&self) -> Pixels {
1616 self.window().rem_size
1617 }
1618}
1619
1620impl Borrow<Window> for WindowContext<'_> {
1621 fn borrow(&self) -> &Window {
1622 &self.window
1623 }
1624}
1625
1626impl BorrowMut<Window> for WindowContext<'_> {
1627 fn borrow_mut(&mut self) -> &mut Window {
1628 &mut self.window
1629 }
1630}
1631
1632impl<T> BorrowWindow for T where T: BorrowMut<AppContext> + BorrowMut<Window> {}
1633
1634pub struct ViewContext<'a, V> {
1635 window_cx: WindowContext<'a>,
1636 view: &'a View<V>,
1637}
1638
1639impl<V> Borrow<AppContext> for ViewContext<'_, V> {
1640 fn borrow(&self) -> &AppContext {
1641 &*self.window_cx.app
1642 }
1643}
1644
1645impl<V> BorrowMut<AppContext> for ViewContext<'_, V> {
1646 fn borrow_mut(&mut self) -> &mut AppContext {
1647 &mut *self.window_cx.app
1648 }
1649}
1650
1651impl<V> Borrow<Window> for ViewContext<'_, V> {
1652 fn borrow(&self) -> &Window {
1653 &*self.window_cx.window
1654 }
1655}
1656
1657impl<V> BorrowMut<Window> for ViewContext<'_, V> {
1658 fn borrow_mut(&mut self) -> &mut Window {
1659 &mut *self.window_cx.window
1660 }
1661}
1662
1663impl<'a, V: 'static> ViewContext<'a, V> {
1664 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window, view: &'a View<V>) -> Self {
1665 Self {
1666 window_cx: WindowContext::new(app, window),
1667 view,
1668 }
1669 }
1670
1671 // todo!("change this to return a reference");
1672 pub fn view(&self) -> View<V> {
1673 self.view.clone()
1674 }
1675
1676 pub fn model(&self) -> Model<V> {
1677 self.view.model.clone()
1678 }
1679
1680 /// Access the underlying window context.
1681 pub fn window_context(&mut self) -> &mut WindowContext<'a> {
1682 &mut self.window_cx
1683 }
1684
1685 pub fn stack<R>(&mut self, order: u32, f: impl FnOnce(&mut Self) -> R) -> R {
1686 self.window.z_index_stack.push(order);
1687 let result = f(self);
1688 self.window.z_index_stack.pop();
1689 result
1690 }
1691
1692 pub fn on_next_frame(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static)
1693 where
1694 V: 'static,
1695 {
1696 let view = self.view();
1697 self.window_cx.on_next_frame(move |cx| view.update(cx, f));
1698 }
1699
1700 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
1701 /// that are currently on the stack to be returned to the app.
1702 pub fn defer(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static) {
1703 let view = self.view().downgrade();
1704 self.window_cx.defer(move |cx| {
1705 view.update(cx, f).ok();
1706 });
1707 }
1708
1709 pub fn observe<V2, E>(
1710 &mut self,
1711 entity: &E,
1712 mut on_notify: impl FnMut(&mut V, E, &mut ViewContext<'_, V>) + 'static,
1713 ) -> Subscription
1714 where
1715 V2: 'static,
1716 V: 'static,
1717 E: Entity<V2>,
1718 {
1719 let view = self.view().downgrade();
1720 let entity_id = entity.entity_id();
1721 let entity = entity.downgrade();
1722 let window_handle = self.window.handle;
1723 self.app.observers.insert(
1724 entity_id,
1725 Box::new(move |cx| {
1726 window_handle
1727 .update(cx, |_, cx| {
1728 if let Some(handle) = E::upgrade_from(&entity) {
1729 view.update(cx, |this, cx| on_notify(this, handle, cx))
1730 .is_ok()
1731 } else {
1732 false
1733 }
1734 })
1735 .unwrap_or(false)
1736 }),
1737 )
1738 }
1739
1740 pub fn subscribe<V2, E>(
1741 &mut self,
1742 entity: &E,
1743 mut on_event: impl FnMut(&mut V, E, &V2::Event, &mut ViewContext<'_, V>) + 'static,
1744 ) -> Subscription
1745 where
1746 V2: EventEmitter,
1747 E: Entity<V2>,
1748 {
1749 let view = self.view().downgrade();
1750 let entity_id = entity.entity_id();
1751 let handle = entity.downgrade();
1752 let window_handle = self.window.handle;
1753 self.app.event_listeners.insert(
1754 entity_id,
1755 Box::new(move |event, cx| {
1756 window_handle
1757 .update(cx, |_, cx| {
1758 if let Some(handle) = E::upgrade_from(&handle) {
1759 let event = event.downcast_ref().expect("invalid event type");
1760 view.update(cx, |this, cx| on_event(this, handle, event, cx))
1761 .is_ok()
1762 } else {
1763 false
1764 }
1765 })
1766 .unwrap_or(false)
1767 }),
1768 )
1769 }
1770
1771 pub fn on_release(
1772 &mut self,
1773 on_release: impl FnOnce(&mut V, &mut WindowContext) + 'static,
1774 ) -> Subscription {
1775 let window_handle = self.window.handle;
1776 self.app.release_listeners.insert(
1777 self.view.model.entity_id,
1778 Box::new(move |this, cx| {
1779 let this = this.downcast_mut().expect("invalid entity type");
1780 let _ = window_handle.update(cx, |_, cx| on_release(this, cx));
1781 }),
1782 )
1783 }
1784
1785 pub fn observe_release<V2, E>(
1786 &mut self,
1787 entity: &E,
1788 mut on_release: impl FnMut(&mut V, &mut V2, &mut ViewContext<'_, V>) + 'static,
1789 ) -> Subscription
1790 where
1791 V: 'static,
1792 V2: 'static,
1793 E: Entity<V2>,
1794 {
1795 let view = self.view().downgrade();
1796 let entity_id = entity.entity_id();
1797 let window_handle = self.window.handle;
1798 self.app.release_listeners.insert(
1799 entity_id,
1800 Box::new(move |entity, cx| {
1801 let entity = entity.downcast_mut().expect("invalid entity type");
1802 let _ = window_handle.update(cx, |_, cx| {
1803 view.update(cx, |this, cx| on_release(this, entity, cx))
1804 });
1805 }),
1806 )
1807 }
1808
1809 pub fn notify(&mut self) {
1810 self.window_cx.notify();
1811 self.window_cx.app.push_effect(Effect::Notify {
1812 emitter: self.view.model.entity_id,
1813 });
1814 }
1815
1816 pub fn observe_window_bounds(
1817 &mut self,
1818 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
1819 ) -> Subscription {
1820 let view = self.view.downgrade();
1821 self.window.bounds_observers.insert(
1822 (),
1823 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
1824 )
1825 }
1826
1827 pub fn observe_window_activation(
1828 &mut self,
1829 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
1830 ) -> Subscription {
1831 let view = self.view.downgrade();
1832 self.window.activation_observers.insert(
1833 (),
1834 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
1835 )
1836 }
1837
1838 pub fn on_focus_changed(
1839 &mut self,
1840 listener: impl Fn(&mut V, &FocusEvent, &mut ViewContext<V>) + 'static,
1841 ) {
1842 let handle = self.view().downgrade();
1843 self.window.focus_listeners.push(Box::new(move |event, cx| {
1844 handle
1845 .update(cx, |view, cx| listener(view, event, cx))
1846 .log_err();
1847 }));
1848 }
1849
1850 pub fn with_key_listeners<R>(
1851 &mut self,
1852 key_listeners: impl IntoIterator<Item = (TypeId, KeyListener<V>)>,
1853 f: impl FnOnce(&mut Self) -> R,
1854 ) -> R {
1855 let old_stack_len = self.window.key_dispatch_stack.len();
1856 if !self.window.freeze_key_dispatch_stack {
1857 for (event_type, listener) in key_listeners {
1858 let handle = self.view().downgrade();
1859 let listener = Box::new(
1860 move |event: &dyn Any,
1861 context_stack: &[&DispatchContext],
1862 phase: DispatchPhase,
1863 cx: &mut WindowContext<'_>| {
1864 handle
1865 .update(cx, |view, cx| {
1866 listener(view, event, context_stack, phase, cx)
1867 })
1868 .log_err()
1869 .flatten()
1870 },
1871 );
1872 self.window
1873 .key_dispatch_stack
1874 .push(KeyDispatchStackFrame::Listener {
1875 event_type,
1876 listener,
1877 });
1878 }
1879 }
1880
1881 let result = f(self);
1882
1883 if !self.window.freeze_key_dispatch_stack {
1884 self.window.key_dispatch_stack.truncate(old_stack_len);
1885 }
1886
1887 result
1888 }
1889
1890 pub fn with_key_dispatch_context<R>(
1891 &mut self,
1892 context: DispatchContext,
1893 f: impl FnOnce(&mut Self) -> R,
1894 ) -> R {
1895 if context.is_empty() {
1896 return f(self);
1897 }
1898
1899 if !self.window.freeze_key_dispatch_stack {
1900 self.window
1901 .key_dispatch_stack
1902 .push(KeyDispatchStackFrame::Context(context));
1903 }
1904
1905 let result = f(self);
1906
1907 if !self.window.freeze_key_dispatch_stack {
1908 self.window.key_dispatch_stack.pop();
1909 }
1910
1911 result
1912 }
1913
1914 pub fn with_focus<R>(
1915 &mut self,
1916 focus_handle: FocusHandle,
1917 f: impl FnOnce(&mut Self) -> R,
1918 ) -> R {
1919 if let Some(parent_focus_id) = self.window.focus_stack.last().copied() {
1920 self.window
1921 .focus_parents_by_child
1922 .insert(focus_handle.id, parent_focus_id);
1923 }
1924 self.window.focus_stack.push(focus_handle.id);
1925
1926 if Some(focus_handle.id) == self.window.focus {
1927 self.window.freeze_key_dispatch_stack = true;
1928 }
1929
1930 let result = f(self);
1931
1932 self.window.focus_stack.pop();
1933 result
1934 }
1935
1936 pub fn spawn<Fut, R>(
1937 &mut self,
1938 f: impl FnOnce(WeakView<V>, AsyncWindowContext) -> Fut,
1939 ) -> Task<R>
1940 where
1941 R: 'static,
1942 Fut: Future<Output = R> + 'static,
1943 {
1944 let view = self.view().downgrade();
1945 self.window_cx.spawn(|cx| f(view, cx))
1946 }
1947
1948 pub fn update_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
1949 where
1950 G: 'static,
1951 {
1952 let mut global = self.app.lease_global::<G>();
1953 let result = f(&mut global, self);
1954 self.app.end_global_lease(global);
1955 result
1956 }
1957
1958 pub fn observe_global<G: 'static>(
1959 &mut self,
1960 f: impl Fn(&mut V, &mut ViewContext<'_, V>) + 'static,
1961 ) -> Subscription {
1962 let window_handle = self.window.handle;
1963 let view = self.view().downgrade();
1964 self.global_observers.insert(
1965 TypeId::of::<G>(),
1966 Box::new(move |cx| {
1967 window_handle
1968 .update(cx, |_, cx| view.update(cx, |view, cx| f(view, cx)).is_ok())
1969 .unwrap_or(false)
1970 }),
1971 )
1972 }
1973
1974 pub fn on_mouse_event<Event: 'static>(
1975 &mut self,
1976 handler: impl Fn(&mut V, &Event, DispatchPhase, &mut ViewContext<V>) + 'static,
1977 ) {
1978 let handle = self.view();
1979 self.window_cx.on_mouse_event(move |event, phase, cx| {
1980 handle.update(cx, |view, cx| {
1981 handler(view, event, phase, cx);
1982 })
1983 });
1984 }
1985}
1986
1987impl<V> ViewContext<'_, V>
1988where
1989 V: EventEmitter,
1990 V::Event: 'static,
1991{
1992 pub fn emit(&mut self, event: V::Event) {
1993 let emitter = self.view.model.entity_id;
1994 self.app.push_effect(Effect::Emit {
1995 emitter,
1996 event: Box::new(event),
1997 });
1998 }
1999}
2000
2001impl<V> Context for ViewContext<'_, V> {
2002 type Result<U> = U;
2003
2004 fn build_model<T: 'static>(
2005 &mut self,
2006 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
2007 ) -> Model<T> {
2008 self.window_cx.build_model(build_model)
2009 }
2010
2011 fn update_model<T: 'static, R>(
2012 &mut self,
2013 model: &Model<T>,
2014 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
2015 ) -> R {
2016 self.window_cx.update_model(model, update)
2017 }
2018
2019 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
2020 where
2021 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
2022 {
2023 self.window_cx.update_window(window, update)
2024 }
2025}
2026
2027impl<V: 'static> VisualContext for ViewContext<'_, V> {
2028 fn build_view<W: 'static>(
2029 &mut self,
2030 build_view: impl FnOnce(&mut ViewContext<'_, W>) -> W,
2031 ) -> Self::Result<View<W>> {
2032 self.window_cx.build_view(build_view)
2033 }
2034
2035 fn update_view<V2: 'static, R>(
2036 &mut self,
2037 view: &View<V2>,
2038 update: impl FnOnce(&mut V2, &mut ViewContext<'_, V2>) -> R,
2039 ) -> Self::Result<R> {
2040 self.window_cx.update_view(view, update)
2041 }
2042
2043 fn replace_root_view<W>(
2044 &mut self,
2045 build_view: impl FnOnce(&mut ViewContext<'_, W>) -> W,
2046 ) -> Self::Result<View<W>>
2047 where
2048 W: Render,
2049 {
2050 self.window_cx.replace_root_view(build_view)
2051 }
2052}
2053
2054impl<'a, V> std::ops::Deref for ViewContext<'a, V> {
2055 type Target = WindowContext<'a>;
2056
2057 fn deref(&self) -> &Self::Target {
2058 &self.window_cx
2059 }
2060}
2061
2062impl<'a, V> std::ops::DerefMut for ViewContext<'a, V> {
2063 fn deref_mut(&mut self) -> &mut Self::Target {
2064 &mut self.window_cx
2065 }
2066}
2067
2068// #[derive(Clone, Copy, Eq, PartialEq, Hash)]
2069slotmap::new_key_type! { pub struct WindowId; }
2070
2071impl WindowId {
2072 pub fn as_u64(&self) -> u64 {
2073 self.0.as_ffi()
2074 }
2075}
2076
2077#[derive(Deref, DerefMut)]
2078pub struct WindowHandle<V> {
2079 #[deref]
2080 #[deref_mut]
2081 pub(crate) any_handle: AnyWindowHandle,
2082 state_type: PhantomData<V>,
2083}
2084
2085impl<V: 'static + Render> WindowHandle<V> {
2086 pub fn new(id: WindowId) -> Self {
2087 WindowHandle {
2088 any_handle: AnyWindowHandle {
2089 id,
2090 state_type: TypeId::of::<V>(),
2091 },
2092 state_type: PhantomData,
2093 }
2094 }
2095
2096 pub fn update<C, R>(
2097 self,
2098 cx: &mut C,
2099 update: impl FnOnce(&mut V, &mut ViewContext<'_, V>) -> R,
2100 ) -> Result<R>
2101 where
2102 C: Context,
2103 {
2104 cx.update_window(self.any_handle, |root_view, cx| {
2105 let view = root_view
2106 .downcast::<V>()
2107 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
2108 Ok(cx.update_view(&view, update))
2109 })?
2110 }
2111}
2112
2113impl<V> Copy for WindowHandle<V> {}
2114
2115impl<V> Clone for WindowHandle<V> {
2116 fn clone(&self) -> Self {
2117 WindowHandle {
2118 any_handle: self.any_handle,
2119 state_type: PhantomData,
2120 }
2121 }
2122}
2123
2124impl<V> PartialEq for WindowHandle<V> {
2125 fn eq(&self, other: &Self) -> bool {
2126 self.any_handle == other.any_handle
2127 }
2128}
2129
2130impl<V> Eq for WindowHandle<V> {}
2131
2132impl<V> Hash for WindowHandle<V> {
2133 fn hash<H: Hasher>(&self, state: &mut H) {
2134 self.any_handle.hash(state);
2135 }
2136}
2137
2138impl<V: 'static> Into<AnyWindowHandle> for WindowHandle<V> {
2139 fn into(self) -> AnyWindowHandle {
2140 self.any_handle
2141 }
2142}
2143
2144#[derive(Copy, Clone, PartialEq, Eq, Hash)]
2145pub struct AnyWindowHandle {
2146 pub(crate) id: WindowId,
2147 state_type: TypeId,
2148}
2149
2150impl AnyWindowHandle {
2151 pub fn window_id(&self) -> WindowId {
2152 self.id
2153 }
2154
2155 pub fn downcast<T: 'static>(&self) -> Option<WindowHandle<T>> {
2156 if TypeId::of::<T>() == self.state_type {
2157 Some(WindowHandle {
2158 any_handle: *self,
2159 state_type: PhantomData,
2160 })
2161 } else {
2162 None
2163 }
2164 }
2165
2166 pub fn update<C, R>(
2167 self,
2168 cx: &mut C,
2169 update: impl FnOnce(AnyView, &mut WindowContext<'_>) -> R,
2170 ) -> Result<R>
2171 where
2172 C: Context,
2173 {
2174 cx.update_window(self, update)
2175 }
2176}
2177
2178#[cfg(any(test, feature = "test-support"))]
2179impl From<SmallVec<[u32; 16]>> for StackingOrder {
2180 fn from(small_vec: SmallVec<[u32; 16]>) -> Self {
2181 StackingOrder(small_vec)
2182 }
2183}
2184
2185#[derive(Clone, Debug, Eq, PartialEq, Hash)]
2186pub enum ElementId {
2187 View(EntityId),
2188 Number(usize),
2189 Name(SharedString),
2190 FocusHandle(FocusId),
2191}
2192
2193impl From<EntityId> for ElementId {
2194 fn from(id: EntityId) -> Self {
2195 ElementId::View(id)
2196 }
2197}
2198
2199impl From<usize> for ElementId {
2200 fn from(id: usize) -> Self {
2201 ElementId::Number(id)
2202 }
2203}
2204
2205impl From<i32> for ElementId {
2206 fn from(id: i32) -> Self {
2207 Self::Number(id as usize)
2208 }
2209}
2210
2211impl From<SharedString> for ElementId {
2212 fn from(name: SharedString) -> Self {
2213 ElementId::Name(name)
2214 }
2215}
2216
2217impl From<&'static str> for ElementId {
2218 fn from(name: &'static str) -> Self {
2219 ElementId::Name(name.into())
2220 }
2221}
2222
2223impl<'a> From<&'a FocusHandle> for ElementId {
2224 fn from(handle: &'a FocusHandle) -> Self {
2225 ElementId::FocusHandle(handle.id)
2226 }
2227}