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 } else if let Some(active_tooltip) = self.app.active_tooltip.take() {
991 self.stack(1, |cx| {
992 cx.with_element_offset(Some(cx.mouse_position()), |cx| {
993 let available_space =
994 size(AvailableSpace::MinContent, AvailableSpace::MinContent);
995 active_tooltip.draw(available_space, cx);
996 });
997 });
998 }
999
1000 self.window.root_view = Some(root_view);
1001 let scene = self.window.scene_builder.build();
1002
1003 self.window.platform_window.draw(scene);
1004 let cursor_style = self
1005 .window
1006 .requested_cursor_style
1007 .take()
1008 .unwrap_or(CursorStyle::Arrow);
1009 self.platform.set_cursor_style(cursor_style);
1010
1011 self.window.dirty = false;
1012 }
1013
1014 fn start_frame(&mut self) {
1015 self.text_system().start_frame();
1016
1017 let window = &mut *self.window;
1018
1019 // Move the current frame element states to the previous frame.
1020 // The new empty element states map will be populated for any element states we
1021 // reference during the upcoming frame.
1022 mem::swap(
1023 &mut window.element_states,
1024 &mut window.prev_frame_element_states,
1025 );
1026 window.element_states.clear();
1027
1028 // Make the current key matchers the previous, and then clear the current.
1029 // An empty key matcher map will be created for every identified element in the
1030 // upcoming frame.
1031 mem::swap(
1032 &mut window.key_matchers,
1033 &mut window.prev_frame_key_matchers,
1034 );
1035 window.key_matchers.clear();
1036
1037 // Clear mouse event listeners, because elements add new element listeners
1038 // when the upcoming frame is painted.
1039 window.mouse_listeners.values_mut().for_each(Vec::clear);
1040
1041 // Clear focus state, because we determine what is focused when the new elements
1042 // in the upcoming frame are initialized.
1043 window.focus_listeners.clear();
1044 window.key_dispatch_stack.clear();
1045 window.focus_parents_by_child.clear();
1046 window.freeze_key_dispatch_stack = false;
1047 }
1048
1049 /// Dispatch a mouse or keyboard event on the window.
1050 fn dispatch_event(&mut self, event: InputEvent) -> bool {
1051 let event = match event {
1052 // Track the mouse position with our own state, since accessing the platform
1053 // API for the mouse position can only occur on the main thread.
1054 InputEvent::MouseMove(mouse_move) => {
1055 self.window.mouse_position = mouse_move.position;
1056 InputEvent::MouseMove(mouse_move)
1057 }
1058 // Translate dragging and dropping of external files from the operating system
1059 // to internal drag and drop events.
1060 InputEvent::FileDrop(file_drop) => match file_drop {
1061 FileDropEvent::Entered { position, files } => {
1062 self.window.mouse_position = position;
1063 if self.active_drag.is_none() {
1064 self.active_drag = Some(AnyDrag {
1065 view: self.build_view(|_| files).into(),
1066 cursor_offset: position,
1067 });
1068 }
1069 InputEvent::MouseDown(MouseDownEvent {
1070 position,
1071 button: MouseButton::Left,
1072 click_count: 1,
1073 modifiers: Modifiers::default(),
1074 })
1075 }
1076 FileDropEvent::Pending { position } => {
1077 self.window.mouse_position = position;
1078 InputEvent::MouseMove(MouseMoveEvent {
1079 position,
1080 pressed_button: Some(MouseButton::Left),
1081 modifiers: Modifiers::default(),
1082 })
1083 }
1084 FileDropEvent::Submit { position } => {
1085 self.window.mouse_position = position;
1086 InputEvent::MouseUp(MouseUpEvent {
1087 button: MouseButton::Left,
1088 position,
1089 modifiers: Modifiers::default(),
1090 click_count: 1,
1091 })
1092 }
1093 FileDropEvent::Exited => InputEvent::MouseUp(MouseUpEvent {
1094 button: MouseButton::Left,
1095 position: Point::default(),
1096 modifiers: Modifiers::default(),
1097 click_count: 1,
1098 }),
1099 },
1100 _ => event,
1101 };
1102
1103 if let Some(any_mouse_event) = event.mouse_event() {
1104 // Handlers may set this to false by calling `stop_propagation`
1105 self.app.propagate_event = true;
1106 self.window.default_prevented = false;
1107
1108 if let Some(mut handlers) = self
1109 .window
1110 .mouse_listeners
1111 .remove(&any_mouse_event.type_id())
1112 {
1113 // Because handlers may add other handlers, we sort every time.
1114 handlers.sort_by(|(a, _), (b, _)| a.cmp(b));
1115
1116 // Capture phase, events bubble from back to front. Handlers for this phase are used for
1117 // special purposes, such as detecting events outside of a given Bounds.
1118 for (_, handler) in &handlers {
1119 handler(any_mouse_event, DispatchPhase::Capture, self);
1120 if !self.app.propagate_event {
1121 break;
1122 }
1123 }
1124
1125 // Bubble phase, where most normal handlers do their work.
1126 if self.app.propagate_event {
1127 for (_, handler) in handlers.iter().rev() {
1128 handler(any_mouse_event, DispatchPhase::Bubble, self);
1129 if !self.app.propagate_event {
1130 break;
1131 }
1132 }
1133 }
1134
1135 if self.app.propagate_event
1136 && any_mouse_event.downcast_ref::<MouseUpEvent>().is_some()
1137 {
1138 self.active_drag = None;
1139 }
1140
1141 // Just in case any handlers added new handlers, which is weird, but possible.
1142 handlers.extend(
1143 self.window
1144 .mouse_listeners
1145 .get_mut(&any_mouse_event.type_id())
1146 .into_iter()
1147 .flat_map(|handlers| handlers.drain(..)),
1148 );
1149 self.window
1150 .mouse_listeners
1151 .insert(any_mouse_event.type_id(), handlers);
1152 }
1153 } else if let Some(any_key_event) = event.keyboard_event() {
1154 let key_dispatch_stack = mem::take(&mut self.window.key_dispatch_stack);
1155 let key_event_type = any_key_event.type_id();
1156 let mut context_stack = SmallVec::<[&DispatchContext; 16]>::new();
1157
1158 for (ix, frame) in key_dispatch_stack.iter().enumerate() {
1159 match frame {
1160 KeyDispatchStackFrame::Listener {
1161 event_type,
1162 listener,
1163 } => {
1164 if key_event_type == *event_type {
1165 if let Some(action) = listener(
1166 any_key_event,
1167 &context_stack,
1168 DispatchPhase::Capture,
1169 self,
1170 ) {
1171 self.dispatch_action(action, &key_dispatch_stack[..ix]);
1172 }
1173 if !self.app.propagate_event {
1174 break;
1175 }
1176 }
1177 }
1178 KeyDispatchStackFrame::Context(context) => {
1179 context_stack.push(&context);
1180 }
1181 }
1182 }
1183
1184 if self.app.propagate_event {
1185 for (ix, frame) in key_dispatch_stack.iter().enumerate().rev() {
1186 match frame {
1187 KeyDispatchStackFrame::Listener {
1188 event_type,
1189 listener,
1190 } => {
1191 if key_event_type == *event_type {
1192 if let Some(action) = listener(
1193 any_key_event,
1194 &context_stack,
1195 DispatchPhase::Bubble,
1196 self,
1197 ) {
1198 self.dispatch_action(action, &key_dispatch_stack[..ix]);
1199 }
1200
1201 if !self.app.propagate_event {
1202 break;
1203 }
1204 }
1205 }
1206 KeyDispatchStackFrame::Context(_) => {
1207 context_stack.pop();
1208 }
1209 }
1210 }
1211 }
1212
1213 drop(context_stack);
1214 self.window.key_dispatch_stack = key_dispatch_stack;
1215 }
1216
1217 true
1218 }
1219
1220 /// Attempt to map a keystroke to an action based on the keymap.
1221 pub fn match_keystroke(
1222 &mut self,
1223 element_id: &GlobalElementId,
1224 keystroke: &Keystroke,
1225 context_stack: &[&DispatchContext],
1226 ) -> KeyMatch {
1227 let key_match = self
1228 .window
1229 .key_matchers
1230 .get_mut(element_id)
1231 .unwrap()
1232 .match_keystroke(keystroke, context_stack);
1233
1234 if key_match.is_some() {
1235 for matcher in self.window.key_matchers.values_mut() {
1236 matcher.clear_pending();
1237 }
1238 }
1239
1240 key_match
1241 }
1242
1243 /// Register the given handler to be invoked whenever the global of the given type
1244 /// is updated.
1245 pub fn observe_global<G: 'static>(
1246 &mut self,
1247 f: impl Fn(&mut WindowContext<'_>) + 'static,
1248 ) -> Subscription {
1249 let window_handle = self.window.handle;
1250 self.global_observers.insert(
1251 TypeId::of::<G>(),
1252 Box::new(move |cx| window_handle.update(cx, |_, cx| f(cx)).is_ok()),
1253 )
1254 }
1255
1256 pub fn activate_window(&self) {
1257 self.window.platform_window.activate();
1258 }
1259
1260 pub fn prompt(
1261 &self,
1262 level: PromptLevel,
1263 msg: &str,
1264 answers: &[&str],
1265 ) -> oneshot::Receiver<usize> {
1266 self.window.platform_window.prompt(level, msg, answers)
1267 }
1268
1269 fn dispatch_action(
1270 &mut self,
1271 action: Box<dyn Action>,
1272 dispatch_stack: &[KeyDispatchStackFrame],
1273 ) {
1274 let action_type = action.as_any().type_id();
1275
1276 if let Some(mut global_listeners) = self.app.global_action_listeners.remove(&action_type) {
1277 for listener in &global_listeners {
1278 listener(action.as_ref(), DispatchPhase::Capture, self);
1279 if !self.app.propagate_event {
1280 break;
1281 }
1282 }
1283 global_listeners.extend(
1284 self.global_action_listeners
1285 .remove(&action_type)
1286 .unwrap_or_default(),
1287 );
1288 self.global_action_listeners
1289 .insert(action_type, global_listeners);
1290 }
1291
1292 if self.app.propagate_event {
1293 for stack_frame in dispatch_stack {
1294 if let KeyDispatchStackFrame::Listener {
1295 event_type,
1296 listener,
1297 } = stack_frame
1298 {
1299 if action_type == *event_type {
1300 listener(action.as_any(), &[], DispatchPhase::Capture, self);
1301 if !self.app.propagate_event {
1302 break;
1303 }
1304 }
1305 }
1306 }
1307 }
1308
1309 if self.app.propagate_event {
1310 for stack_frame in dispatch_stack.iter().rev() {
1311 if let KeyDispatchStackFrame::Listener {
1312 event_type,
1313 listener,
1314 } = stack_frame
1315 {
1316 if action_type == *event_type {
1317 listener(action.as_any(), &[], DispatchPhase::Bubble, self);
1318 if !self.app.propagate_event {
1319 break;
1320 }
1321 }
1322 }
1323 }
1324 }
1325
1326 if self.app.propagate_event {
1327 if let Some(mut global_listeners) =
1328 self.app.global_action_listeners.remove(&action_type)
1329 {
1330 for listener in global_listeners.iter().rev() {
1331 listener(action.as_ref(), DispatchPhase::Bubble, self);
1332 if !self.app.propagate_event {
1333 break;
1334 }
1335 }
1336 global_listeners.extend(
1337 self.global_action_listeners
1338 .remove(&action_type)
1339 .unwrap_or_default(),
1340 );
1341 self.global_action_listeners
1342 .insert(action_type, global_listeners);
1343 }
1344 }
1345 }
1346}
1347
1348impl Context for WindowContext<'_> {
1349 type Result<T> = T;
1350
1351 fn build_model<T>(
1352 &mut self,
1353 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
1354 ) -> Model<T>
1355 where
1356 T: 'static,
1357 {
1358 let slot = self.app.entities.reserve();
1359 let model = build_model(&mut ModelContext::new(&mut *self.app, slot.downgrade()));
1360 self.entities.insert(slot, model)
1361 }
1362
1363 fn update_model<T: 'static, R>(
1364 &mut self,
1365 model: &Model<T>,
1366 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
1367 ) -> R {
1368 let mut entity = self.entities.lease(model);
1369 let result = update(
1370 &mut *entity,
1371 &mut ModelContext::new(&mut *self.app, model.downgrade()),
1372 );
1373 self.entities.end_lease(entity);
1374 result
1375 }
1376
1377 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
1378 where
1379 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
1380 {
1381 if window == self.window.handle {
1382 let root_view = self.window.root_view.clone().unwrap();
1383 Ok(update(root_view, self))
1384 } else {
1385 window.update(self.app, update)
1386 }
1387 }
1388}
1389
1390impl VisualContext for WindowContext<'_> {
1391 fn build_view<V>(
1392 &mut self,
1393 build_view_state: impl FnOnce(&mut ViewContext<'_, V>) -> V,
1394 ) -> Self::Result<View<V>>
1395 where
1396 V: 'static,
1397 {
1398 let slot = self.app.entities.reserve();
1399 let view = View {
1400 model: slot.clone(),
1401 };
1402 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
1403 let entity = build_view_state(&mut cx);
1404 self.entities.insert(slot, entity);
1405 view
1406 }
1407
1408 /// Update the given view. Prefer calling `View::update` instead, which calls this method.
1409 fn update_view<T: 'static, R>(
1410 &mut self,
1411 view: &View<T>,
1412 update: impl FnOnce(&mut T, &mut ViewContext<'_, T>) -> R,
1413 ) -> Self::Result<R> {
1414 let mut lease = self.app.entities.lease(&view.model);
1415 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
1416 let result = update(&mut *lease, &mut cx);
1417 cx.app.entities.end_lease(lease);
1418 result
1419 }
1420
1421 fn replace_root_view<V>(
1422 &mut self,
1423 build_view: impl FnOnce(&mut ViewContext<'_, V>) -> V,
1424 ) -> Self::Result<View<V>>
1425 where
1426 V: Render,
1427 {
1428 let slot = self.app.entities.reserve();
1429 let view = View {
1430 model: slot.clone(),
1431 };
1432 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
1433 let entity = build_view(&mut cx);
1434 self.entities.insert(slot, entity);
1435 self.window.root_view = Some(view.clone().into());
1436 view
1437 }
1438}
1439
1440impl<'a> std::ops::Deref for WindowContext<'a> {
1441 type Target = AppContext;
1442
1443 fn deref(&self) -> &Self::Target {
1444 &self.app
1445 }
1446}
1447
1448impl<'a> std::ops::DerefMut for WindowContext<'a> {
1449 fn deref_mut(&mut self) -> &mut Self::Target {
1450 &mut self.app
1451 }
1452}
1453
1454impl<'a> Borrow<AppContext> for WindowContext<'a> {
1455 fn borrow(&self) -> &AppContext {
1456 &self.app
1457 }
1458}
1459
1460impl<'a> BorrowMut<AppContext> for WindowContext<'a> {
1461 fn borrow_mut(&mut self) -> &mut AppContext {
1462 &mut self.app
1463 }
1464}
1465
1466pub trait BorrowWindow: BorrowMut<Window> + BorrowMut<AppContext> {
1467 fn app_mut(&mut self) -> &mut AppContext {
1468 self.borrow_mut()
1469 }
1470
1471 fn window(&self) -> &Window {
1472 self.borrow()
1473 }
1474
1475 fn window_mut(&mut self) -> &mut Window {
1476 self.borrow_mut()
1477 }
1478
1479 /// Pushes the given element id onto the global stack and invokes the given closure
1480 /// with a `GlobalElementId`, which disambiguates the given id in the context of its ancestor
1481 /// ids. Because elements are discarded and recreated on each frame, the `GlobalElementId` is
1482 /// used to associate state with identified elements across separate frames.
1483 fn with_element_id<R>(
1484 &mut self,
1485 id: impl Into<ElementId>,
1486 f: impl FnOnce(GlobalElementId, &mut Self) -> R,
1487 ) -> R {
1488 let keymap = self.app_mut().keymap.clone();
1489 let window = self.window_mut();
1490 window.element_id_stack.push(id.into());
1491 let global_id = window.element_id_stack.clone();
1492
1493 if window.key_matchers.get(&global_id).is_none() {
1494 window.key_matchers.insert(
1495 global_id.clone(),
1496 window
1497 .prev_frame_key_matchers
1498 .remove(&global_id)
1499 .unwrap_or_else(|| KeyMatcher::new(keymap)),
1500 );
1501 }
1502
1503 let result = f(global_id, self);
1504 let window: &mut Window = self.borrow_mut();
1505 window.element_id_stack.pop();
1506 result
1507 }
1508
1509 /// Invoke the given function with the given content mask after intersecting it
1510 /// with the current mask.
1511 fn with_content_mask<R>(
1512 &mut self,
1513 mask: ContentMask<Pixels>,
1514 f: impl FnOnce(&mut Self) -> R,
1515 ) -> R {
1516 let mask = mask.intersect(&self.content_mask());
1517 self.window_mut().content_mask_stack.push(mask);
1518 let result = f(self);
1519 self.window_mut().content_mask_stack.pop();
1520 result
1521 }
1522
1523 /// Update the global element offset based on the given offset. This is used to implement
1524 /// scrolling and position drag handles.
1525 fn with_element_offset<R>(
1526 &mut self,
1527 offset: Option<Point<Pixels>>,
1528 f: impl FnOnce(&mut Self) -> R,
1529 ) -> R {
1530 let Some(offset) = offset else {
1531 return f(self);
1532 };
1533
1534 let offset = self.element_offset() + offset;
1535 self.window_mut().element_offset_stack.push(offset);
1536 let result = f(self);
1537 self.window_mut().element_offset_stack.pop();
1538 result
1539 }
1540
1541 /// Obtain the current element offset.
1542 fn element_offset(&self) -> Point<Pixels> {
1543 self.window()
1544 .element_offset_stack
1545 .last()
1546 .copied()
1547 .unwrap_or_default()
1548 }
1549
1550 /// Update or intialize state for an element with the given id that lives across multiple
1551 /// frames. If an element with this id existed in the previous frame, its state will be passed
1552 /// to the given closure. The state returned by the closure will be stored so it can be referenced
1553 /// when drawing the next frame.
1554 fn with_element_state<S, R>(
1555 &mut self,
1556 id: ElementId,
1557 f: impl FnOnce(Option<S>, &mut Self) -> (R, S),
1558 ) -> R
1559 where
1560 S: 'static,
1561 {
1562 self.with_element_id(id, |global_id, cx| {
1563 if let Some(any) = cx
1564 .window_mut()
1565 .element_states
1566 .remove(&global_id)
1567 .or_else(|| cx.window_mut().prev_frame_element_states.remove(&global_id))
1568 {
1569 // Using the extra inner option to avoid needing to reallocate a new box.
1570 let mut state_box = any
1571 .downcast::<Option<S>>()
1572 .expect("invalid element state type for id");
1573 let state = state_box
1574 .take()
1575 .expect("element state is already on the stack");
1576 let (result, state) = f(Some(state), cx);
1577 state_box.replace(state);
1578 cx.window_mut().element_states.insert(global_id, state_box);
1579 result
1580 } else {
1581 let (result, state) = f(None, cx);
1582 cx.window_mut()
1583 .element_states
1584 .insert(global_id, Box::new(Some(state)));
1585 result
1586 }
1587 })
1588 }
1589
1590 /// Like `with_element_state`, but for situations where the element_id is optional. If the
1591 /// id is `None`, no state will be retrieved or stored.
1592 fn with_optional_element_state<S, R>(
1593 &mut self,
1594 element_id: Option<ElementId>,
1595 f: impl FnOnce(Option<S>, &mut Self) -> (R, S),
1596 ) -> R
1597 where
1598 S: 'static,
1599 {
1600 if let Some(element_id) = element_id {
1601 self.with_element_state(element_id, f)
1602 } else {
1603 f(None, self).0
1604 }
1605 }
1606
1607 /// Obtain the current content mask.
1608 fn content_mask(&self) -> ContentMask<Pixels> {
1609 self.window()
1610 .content_mask_stack
1611 .last()
1612 .cloned()
1613 .unwrap_or_else(|| ContentMask {
1614 bounds: Bounds {
1615 origin: Point::default(),
1616 size: self.window().content_size,
1617 },
1618 })
1619 }
1620
1621 /// The size of an em for the base font of the application. Adjusting this value allows the
1622 /// UI to scale, just like zooming a web page.
1623 fn rem_size(&self) -> Pixels {
1624 self.window().rem_size
1625 }
1626}
1627
1628impl Borrow<Window> for WindowContext<'_> {
1629 fn borrow(&self) -> &Window {
1630 &self.window
1631 }
1632}
1633
1634impl BorrowMut<Window> for WindowContext<'_> {
1635 fn borrow_mut(&mut self) -> &mut Window {
1636 &mut self.window
1637 }
1638}
1639
1640impl<T> BorrowWindow for T where T: BorrowMut<AppContext> + BorrowMut<Window> {}
1641
1642pub struct ViewContext<'a, V> {
1643 window_cx: WindowContext<'a>,
1644 view: &'a View<V>,
1645}
1646
1647impl<V> Borrow<AppContext> for ViewContext<'_, V> {
1648 fn borrow(&self) -> &AppContext {
1649 &*self.window_cx.app
1650 }
1651}
1652
1653impl<V> BorrowMut<AppContext> for ViewContext<'_, V> {
1654 fn borrow_mut(&mut self) -> &mut AppContext {
1655 &mut *self.window_cx.app
1656 }
1657}
1658
1659impl<V> Borrow<Window> for ViewContext<'_, V> {
1660 fn borrow(&self) -> &Window {
1661 &*self.window_cx.window
1662 }
1663}
1664
1665impl<V> BorrowMut<Window> for ViewContext<'_, V> {
1666 fn borrow_mut(&mut self) -> &mut Window {
1667 &mut *self.window_cx.window
1668 }
1669}
1670
1671impl<'a, V: 'static> ViewContext<'a, V> {
1672 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window, view: &'a View<V>) -> Self {
1673 Self {
1674 window_cx: WindowContext::new(app, window),
1675 view,
1676 }
1677 }
1678
1679 // todo!("change this to return a reference");
1680 pub fn view(&self) -> View<V> {
1681 self.view.clone()
1682 }
1683
1684 pub fn model(&self) -> Model<V> {
1685 self.view.model.clone()
1686 }
1687
1688 /// Access the underlying window context.
1689 pub fn window_context(&mut self) -> &mut WindowContext<'a> {
1690 &mut self.window_cx
1691 }
1692
1693 pub fn stack<R>(&mut self, order: u32, f: impl FnOnce(&mut Self) -> R) -> R {
1694 self.window.z_index_stack.push(order);
1695 let result = f(self);
1696 self.window.z_index_stack.pop();
1697 result
1698 }
1699
1700 pub fn on_next_frame(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static)
1701 where
1702 V: 'static,
1703 {
1704 let view = self.view();
1705 self.window_cx.on_next_frame(move |cx| view.update(cx, f));
1706 }
1707
1708 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
1709 /// that are currently on the stack to be returned to the app.
1710 pub fn defer(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static) {
1711 let view = self.view().downgrade();
1712 self.window_cx.defer(move |cx| {
1713 view.update(cx, f).ok();
1714 });
1715 }
1716
1717 pub fn observe<V2, E>(
1718 &mut self,
1719 entity: &E,
1720 mut on_notify: impl FnMut(&mut V, E, &mut ViewContext<'_, V>) + 'static,
1721 ) -> Subscription
1722 where
1723 V2: 'static,
1724 V: 'static,
1725 E: Entity<V2>,
1726 {
1727 let view = self.view().downgrade();
1728 let entity_id = entity.entity_id();
1729 let entity = entity.downgrade();
1730 let window_handle = self.window.handle;
1731 self.app.observers.insert(
1732 entity_id,
1733 Box::new(move |cx| {
1734 window_handle
1735 .update(cx, |_, cx| {
1736 if let Some(handle) = E::upgrade_from(&entity) {
1737 view.update(cx, |this, cx| on_notify(this, handle, cx))
1738 .is_ok()
1739 } else {
1740 false
1741 }
1742 })
1743 .unwrap_or(false)
1744 }),
1745 )
1746 }
1747
1748 pub fn subscribe<V2, E>(
1749 &mut self,
1750 entity: &E,
1751 mut on_event: impl FnMut(&mut V, E, &V2::Event, &mut ViewContext<'_, V>) + 'static,
1752 ) -> Subscription
1753 where
1754 V2: EventEmitter,
1755 E: Entity<V2>,
1756 {
1757 let view = self.view().downgrade();
1758 let entity_id = entity.entity_id();
1759 let handle = entity.downgrade();
1760 let window_handle = self.window.handle;
1761 self.app.event_listeners.insert(
1762 entity_id,
1763 Box::new(move |event, cx| {
1764 window_handle
1765 .update(cx, |_, cx| {
1766 if let Some(handle) = E::upgrade_from(&handle) {
1767 let event = event.downcast_ref().expect("invalid event type");
1768 view.update(cx, |this, cx| on_event(this, handle, event, cx))
1769 .is_ok()
1770 } else {
1771 false
1772 }
1773 })
1774 .unwrap_or(false)
1775 }),
1776 )
1777 }
1778
1779 pub fn on_release(
1780 &mut self,
1781 on_release: impl FnOnce(&mut V, &mut WindowContext) + 'static,
1782 ) -> Subscription {
1783 let window_handle = self.window.handle;
1784 self.app.release_listeners.insert(
1785 self.view.model.entity_id,
1786 Box::new(move |this, cx| {
1787 let this = this.downcast_mut().expect("invalid entity type");
1788 let _ = window_handle.update(cx, |_, cx| on_release(this, cx));
1789 }),
1790 )
1791 }
1792
1793 pub fn observe_release<V2, E>(
1794 &mut self,
1795 entity: &E,
1796 mut on_release: impl FnMut(&mut V, &mut V2, &mut ViewContext<'_, V>) + 'static,
1797 ) -> Subscription
1798 where
1799 V: 'static,
1800 V2: 'static,
1801 E: Entity<V2>,
1802 {
1803 let view = self.view().downgrade();
1804 let entity_id = entity.entity_id();
1805 let window_handle = self.window.handle;
1806 self.app.release_listeners.insert(
1807 entity_id,
1808 Box::new(move |entity, cx| {
1809 let entity = entity.downcast_mut().expect("invalid entity type");
1810 let _ = window_handle.update(cx, |_, cx| {
1811 view.update(cx, |this, cx| on_release(this, entity, cx))
1812 });
1813 }),
1814 )
1815 }
1816
1817 pub fn notify(&mut self) {
1818 self.window_cx.notify();
1819 self.window_cx.app.push_effect(Effect::Notify {
1820 emitter: self.view.model.entity_id,
1821 });
1822 }
1823
1824 pub fn observe_window_bounds(
1825 &mut self,
1826 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
1827 ) -> Subscription {
1828 let view = self.view.downgrade();
1829 self.window.bounds_observers.insert(
1830 (),
1831 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
1832 )
1833 }
1834
1835 pub fn observe_window_activation(
1836 &mut self,
1837 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
1838 ) -> Subscription {
1839 let view = self.view.downgrade();
1840 self.window.activation_observers.insert(
1841 (),
1842 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
1843 )
1844 }
1845
1846 pub fn on_focus_changed(
1847 &mut self,
1848 listener: impl Fn(&mut V, &FocusEvent, &mut ViewContext<V>) + 'static,
1849 ) {
1850 let handle = self.view().downgrade();
1851 self.window.focus_listeners.push(Box::new(move |event, cx| {
1852 handle
1853 .update(cx, |view, cx| listener(view, event, cx))
1854 .log_err();
1855 }));
1856 }
1857
1858 pub fn with_key_listeners<R>(
1859 &mut self,
1860 key_listeners: impl IntoIterator<Item = (TypeId, KeyListener<V>)>,
1861 f: impl FnOnce(&mut Self) -> R,
1862 ) -> R {
1863 let old_stack_len = self.window.key_dispatch_stack.len();
1864 if !self.window.freeze_key_dispatch_stack {
1865 for (event_type, listener) in key_listeners {
1866 let handle = self.view().downgrade();
1867 let listener = Box::new(
1868 move |event: &dyn Any,
1869 context_stack: &[&DispatchContext],
1870 phase: DispatchPhase,
1871 cx: &mut WindowContext<'_>| {
1872 handle
1873 .update(cx, |view, cx| {
1874 listener(view, event, context_stack, phase, cx)
1875 })
1876 .log_err()
1877 .flatten()
1878 },
1879 );
1880 self.window
1881 .key_dispatch_stack
1882 .push(KeyDispatchStackFrame::Listener {
1883 event_type,
1884 listener,
1885 });
1886 }
1887 }
1888
1889 let result = f(self);
1890
1891 if !self.window.freeze_key_dispatch_stack {
1892 self.window.key_dispatch_stack.truncate(old_stack_len);
1893 }
1894
1895 result
1896 }
1897
1898 pub fn with_key_dispatch_context<R>(
1899 &mut self,
1900 context: DispatchContext,
1901 f: impl FnOnce(&mut Self) -> R,
1902 ) -> R {
1903 if context.is_empty() {
1904 return f(self);
1905 }
1906
1907 if !self.window.freeze_key_dispatch_stack {
1908 self.window
1909 .key_dispatch_stack
1910 .push(KeyDispatchStackFrame::Context(context));
1911 }
1912
1913 let result = f(self);
1914
1915 if !self.window.freeze_key_dispatch_stack {
1916 self.window.key_dispatch_stack.pop();
1917 }
1918
1919 result
1920 }
1921
1922 pub fn with_focus<R>(
1923 &mut self,
1924 focus_handle: FocusHandle,
1925 f: impl FnOnce(&mut Self) -> R,
1926 ) -> R {
1927 if let Some(parent_focus_id) = self.window.focus_stack.last().copied() {
1928 self.window
1929 .focus_parents_by_child
1930 .insert(focus_handle.id, parent_focus_id);
1931 }
1932 self.window.focus_stack.push(focus_handle.id);
1933
1934 if Some(focus_handle.id) == self.window.focus {
1935 self.window.freeze_key_dispatch_stack = true;
1936 }
1937
1938 let result = f(self);
1939
1940 self.window.focus_stack.pop();
1941 result
1942 }
1943
1944 pub fn spawn<Fut, R>(
1945 &mut self,
1946 f: impl FnOnce(WeakView<V>, AsyncWindowContext) -> Fut,
1947 ) -> Task<R>
1948 where
1949 R: 'static,
1950 Fut: Future<Output = R> + 'static,
1951 {
1952 let view = self.view().downgrade();
1953 self.window_cx.spawn(|cx| f(view, cx))
1954 }
1955
1956 pub fn update_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
1957 where
1958 G: 'static,
1959 {
1960 let mut global = self.app.lease_global::<G>();
1961 let result = f(&mut global, self);
1962 self.app.end_global_lease(global);
1963 result
1964 }
1965
1966 pub fn observe_global<G: 'static>(
1967 &mut self,
1968 f: impl Fn(&mut V, &mut ViewContext<'_, V>) + 'static,
1969 ) -> Subscription {
1970 let window_handle = self.window.handle;
1971 let view = self.view().downgrade();
1972 self.global_observers.insert(
1973 TypeId::of::<G>(),
1974 Box::new(move |cx| {
1975 window_handle
1976 .update(cx, |_, cx| view.update(cx, |view, cx| f(view, cx)).is_ok())
1977 .unwrap_or(false)
1978 }),
1979 )
1980 }
1981
1982 pub fn on_mouse_event<Event: 'static>(
1983 &mut self,
1984 handler: impl Fn(&mut V, &Event, DispatchPhase, &mut ViewContext<V>) + 'static,
1985 ) {
1986 let handle = self.view();
1987 self.window_cx.on_mouse_event(move |event, phase, cx| {
1988 handle.update(cx, |view, cx| {
1989 handler(view, event, phase, cx);
1990 })
1991 });
1992 }
1993}
1994
1995impl<V> ViewContext<'_, V>
1996where
1997 V: EventEmitter,
1998 V::Event: 'static,
1999{
2000 pub fn emit(&mut self, event: V::Event) {
2001 let emitter = self.view.model.entity_id;
2002 self.app.push_effect(Effect::Emit {
2003 emitter,
2004 event: Box::new(event),
2005 });
2006 }
2007}
2008
2009impl<V> Context for ViewContext<'_, V> {
2010 type Result<U> = U;
2011
2012 fn build_model<T: 'static>(
2013 &mut self,
2014 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
2015 ) -> Model<T> {
2016 self.window_cx.build_model(build_model)
2017 }
2018
2019 fn update_model<T: 'static, R>(
2020 &mut self,
2021 model: &Model<T>,
2022 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
2023 ) -> R {
2024 self.window_cx.update_model(model, update)
2025 }
2026
2027 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
2028 where
2029 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
2030 {
2031 self.window_cx.update_window(window, update)
2032 }
2033}
2034
2035impl<V: 'static> VisualContext for ViewContext<'_, V> {
2036 fn build_view<W: 'static>(
2037 &mut self,
2038 build_view: impl FnOnce(&mut ViewContext<'_, W>) -> W,
2039 ) -> Self::Result<View<W>> {
2040 self.window_cx.build_view(build_view)
2041 }
2042
2043 fn update_view<V2: 'static, R>(
2044 &mut self,
2045 view: &View<V2>,
2046 update: impl FnOnce(&mut V2, &mut ViewContext<'_, V2>) -> R,
2047 ) -> Self::Result<R> {
2048 self.window_cx.update_view(view, update)
2049 }
2050
2051 fn replace_root_view<W>(
2052 &mut self,
2053 build_view: impl FnOnce(&mut ViewContext<'_, W>) -> W,
2054 ) -> Self::Result<View<W>>
2055 where
2056 W: Render,
2057 {
2058 self.window_cx.replace_root_view(build_view)
2059 }
2060}
2061
2062impl<'a, V> std::ops::Deref for ViewContext<'a, V> {
2063 type Target = WindowContext<'a>;
2064
2065 fn deref(&self) -> &Self::Target {
2066 &self.window_cx
2067 }
2068}
2069
2070impl<'a, V> std::ops::DerefMut for ViewContext<'a, V> {
2071 fn deref_mut(&mut self) -> &mut Self::Target {
2072 &mut self.window_cx
2073 }
2074}
2075
2076// #[derive(Clone, Copy, Eq, PartialEq, Hash)]
2077slotmap::new_key_type! { pub struct WindowId; }
2078
2079impl WindowId {
2080 pub fn as_u64(&self) -> u64 {
2081 self.0.as_ffi()
2082 }
2083}
2084
2085#[derive(Deref, DerefMut)]
2086pub struct WindowHandle<V> {
2087 #[deref]
2088 #[deref_mut]
2089 pub(crate) any_handle: AnyWindowHandle,
2090 state_type: PhantomData<V>,
2091}
2092
2093impl<V: 'static + Render> WindowHandle<V> {
2094 pub fn new(id: WindowId) -> Self {
2095 WindowHandle {
2096 any_handle: AnyWindowHandle {
2097 id,
2098 state_type: TypeId::of::<V>(),
2099 },
2100 state_type: PhantomData,
2101 }
2102 }
2103
2104 pub fn update<C, R>(
2105 self,
2106 cx: &mut C,
2107 update: impl FnOnce(&mut V, &mut ViewContext<'_, V>) -> R,
2108 ) -> Result<R>
2109 where
2110 C: Context,
2111 {
2112 cx.update_window(self.any_handle, |root_view, cx| {
2113 let view = root_view
2114 .downcast::<V>()
2115 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
2116 Ok(cx.update_view(&view, update))
2117 })?
2118 }
2119}
2120
2121impl<V> Copy for WindowHandle<V> {}
2122
2123impl<V> Clone for WindowHandle<V> {
2124 fn clone(&self) -> Self {
2125 WindowHandle {
2126 any_handle: self.any_handle,
2127 state_type: PhantomData,
2128 }
2129 }
2130}
2131
2132impl<V> PartialEq for WindowHandle<V> {
2133 fn eq(&self, other: &Self) -> bool {
2134 self.any_handle == other.any_handle
2135 }
2136}
2137
2138impl<V> Eq for WindowHandle<V> {}
2139
2140impl<V> Hash for WindowHandle<V> {
2141 fn hash<H: Hasher>(&self, state: &mut H) {
2142 self.any_handle.hash(state);
2143 }
2144}
2145
2146impl<V: 'static> Into<AnyWindowHandle> for WindowHandle<V> {
2147 fn into(self) -> AnyWindowHandle {
2148 self.any_handle
2149 }
2150}
2151
2152#[derive(Copy, Clone, PartialEq, Eq, Hash)]
2153pub struct AnyWindowHandle {
2154 pub(crate) id: WindowId,
2155 state_type: TypeId,
2156}
2157
2158impl AnyWindowHandle {
2159 pub fn window_id(&self) -> WindowId {
2160 self.id
2161 }
2162
2163 pub fn downcast<T: 'static>(&self) -> Option<WindowHandle<T>> {
2164 if TypeId::of::<T>() == self.state_type {
2165 Some(WindowHandle {
2166 any_handle: *self,
2167 state_type: PhantomData,
2168 })
2169 } else {
2170 None
2171 }
2172 }
2173
2174 pub fn update<C, R>(
2175 self,
2176 cx: &mut C,
2177 update: impl FnOnce(AnyView, &mut WindowContext<'_>) -> R,
2178 ) -> Result<R>
2179 where
2180 C: Context,
2181 {
2182 cx.update_window(self, update)
2183 }
2184}
2185
2186#[cfg(any(test, feature = "test-support"))]
2187impl From<SmallVec<[u32; 16]>> for StackingOrder {
2188 fn from(small_vec: SmallVec<[u32; 16]>) -> Self {
2189 StackingOrder(small_vec)
2190 }
2191}
2192
2193#[derive(Clone, Debug, Eq, PartialEq, Hash)]
2194pub enum ElementId {
2195 View(EntityId),
2196 Number(usize),
2197 Name(SharedString),
2198 FocusHandle(FocusId),
2199}
2200
2201impl From<EntityId> for ElementId {
2202 fn from(id: EntityId) -> Self {
2203 ElementId::View(id)
2204 }
2205}
2206
2207impl From<usize> for ElementId {
2208 fn from(id: usize) -> Self {
2209 ElementId::Number(id)
2210 }
2211}
2212
2213impl From<i32> for ElementId {
2214 fn from(id: i32) -> Self {
2215 Self::Number(id as usize)
2216 }
2217}
2218
2219impl From<SharedString> for ElementId {
2220 fn from(name: SharedString) -> Self {
2221 ElementId::Name(name)
2222 }
2223}
2224
2225impl From<&'static str> for ElementId {
2226 fn from(name: &'static str) -> Self {
2227 ElementId::Name(name.into())
2228 }
2229}
2230
2231impl<'a> From<&'a FocusHandle> for ElementId {
2232 fn from(handle: &'a FocusHandle) -> Self {
2233 ElementId::FocusHandle(handle.id)
2234 }
2235}