1use crate::{
2 px, size, Action, AnyBox, AnyView, AppContext, AsyncWindowContext, AvailableSpace, Bounds,
3 BoxShadow, Context, Corners, DevicePixels, DispatchContext, DisplayId, Edges, Effect, Element,
4 EntityId, EventEmitter, FileDropEvent, FocusEvent, FontId, GlobalElementId, GlyphId, Handle,
5 Hsla, ImageData, InputEvent, IsZero, KeyListener, KeyMatch, KeyMatcher, Keystroke, LayoutId,
6 MainThread, MainThreadOnly, MonochromeSprite, MouseMoveEvent, MouseUpEvent, Path, Pixels,
7 PlatformAtlas, PlatformWindow, Point, PolychromeSprite, Quad, Reference, RenderGlyphParams,
8 RenderImageParams, RenderSvgParams, ScaledPixels, SceneBuilder, Shadow, SharedString, Size,
9 Style, Subscription, TaffyLayoutEngine, Task, Underline, UnderlineStyle, WeakHandle,
10 WindowOptions, SUBPIXEL_VARIANTS,
11};
12use anyhow::Result;
13use collections::HashMap;
14use derive_more::{Deref, DerefMut};
15use parking_lot::RwLock;
16use slotmap::SlotMap;
17use smallvec::SmallVec;
18use std::{
19 any::{Any, TypeId},
20 borrow::{Borrow, BorrowMut, Cow},
21 fmt::Debug,
22 future::Future,
23 marker::PhantomData,
24 mem,
25 sync::{
26 atomic::{AtomicUsize, Ordering::SeqCst},
27 Arc,
28 },
29};
30use util::ResultExt;
31
32#[derive(Deref, DerefMut, Ord, PartialOrd, Eq, PartialEq, Clone, Default)]
33pub struct StackingOrder(pub(crate) SmallVec<[u32; 16]>);
34
35#[derive(Default, Copy, Clone, Debug, Eq, PartialEq)]
36pub enum DispatchPhase {
37 /// After the capture phase comes the bubble phase, in which event handlers are
38 /// invoked front to back. This is the phase you'll usually want to use for event handlers.
39 #[default]
40 Bubble,
41 /// During the initial capture phase, event handlers are invoked back to front. This phase
42 /// is used for special purposes such as clearing the "pressed" state for click events. If
43 /// you stop event propagation during this phase, you need to know what you're doing. Handlers
44 /// outside of the immediate region may rely on detecting non-local events during this phase.
45 Capture,
46}
47
48type AnyListener = Arc<dyn Fn(&dyn Any, DispatchPhase, &mut WindowContext) + Send + Sync + 'static>;
49type AnyKeyListener = Arc<
50 dyn Fn(
51 &dyn Any,
52 &[&DispatchContext],
53 DispatchPhase,
54 &mut WindowContext,
55 ) -> Option<Box<dyn Action>>
56 + Send
57 + Sync
58 + 'static,
59>;
60type AnyFocusListener = Arc<dyn Fn(&FocusEvent, &mut WindowContext) + Send + Sync + 'static>;
61
62slotmap::new_key_type! { pub struct FocusId; }
63
64pub struct FocusHandle {
65 pub(crate) id: FocusId,
66 handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
67}
68
69impl FocusHandle {
70 pub(crate) fn new(handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>) -> Self {
71 let id = handles.write().insert(AtomicUsize::new(1));
72 Self {
73 id,
74 handles: handles.clone(),
75 }
76 }
77
78 pub(crate) fn for_id(
79 id: FocusId,
80 handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
81 ) -> Option<Self> {
82 let lock = handles.read();
83 let ref_count = lock.get(id)?;
84 if ref_count.load(SeqCst) == 0 {
85 None
86 } else {
87 ref_count.fetch_add(1, SeqCst);
88 Some(Self {
89 id,
90 handles: handles.clone(),
91 })
92 }
93 }
94
95 pub fn is_focused(&self, cx: &WindowContext) -> bool {
96 cx.window.focus == Some(self.id)
97 }
98
99 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
100 cx.focused()
101 .map_or(false, |focused| self.contains(&focused, cx))
102 }
103
104 pub fn within_focused(&self, cx: &WindowContext) -> bool {
105 let focused = cx.focused();
106 focused.map_or(false, |focused| focused.contains(self, cx))
107 }
108
109 pub(crate) fn contains(&self, other: &Self, cx: &WindowContext) -> bool {
110 let mut ancestor = Some(other.id);
111 while let Some(ancestor_id) = ancestor {
112 if self.id == ancestor_id {
113 return true;
114 } else {
115 ancestor = cx.window.focus_parents_by_child.get(&ancestor_id).copied();
116 }
117 }
118 false
119 }
120}
121
122impl Clone for FocusHandle {
123 fn clone(&self) -> Self {
124 Self::for_id(self.id, &self.handles).unwrap()
125 }
126}
127
128impl PartialEq for FocusHandle {
129 fn eq(&self, other: &Self) -> bool {
130 self.id == other.id
131 }
132}
133
134impl Eq for FocusHandle {}
135
136impl Drop for FocusHandle {
137 fn drop(&mut self) {
138 self.handles
139 .read()
140 .get(self.id)
141 .unwrap()
142 .fetch_sub(1, SeqCst);
143 }
144}
145
146pub struct Window {
147 handle: AnyWindowHandle,
148 platform_window: MainThreadOnly<Box<dyn PlatformWindow>>,
149 display_id: DisplayId,
150 sprite_atlas: Arc<dyn PlatformAtlas>,
151 rem_size: Pixels,
152 content_size: Size<Pixels>,
153 layout_engine: TaffyLayoutEngine,
154 pub(crate) root_view: Option<AnyView>,
155 pub(crate) element_id_stack: GlobalElementId,
156 prev_frame_element_states: HashMap<GlobalElementId, AnyBox>,
157 element_states: HashMap<GlobalElementId, AnyBox>,
158 prev_frame_key_matchers: HashMap<GlobalElementId, KeyMatcher>,
159 key_matchers: HashMap<GlobalElementId, KeyMatcher>,
160 z_index_stack: StackingOrder,
161 content_mask_stack: Vec<ContentMask<Pixels>>,
162 element_offset_stack: Vec<Point<Pixels>>,
163 mouse_listeners: HashMap<TypeId, Vec<(StackingOrder, AnyListener)>>,
164 key_dispatch_stack: Vec<KeyDispatchStackFrame>,
165 freeze_key_dispatch_stack: bool,
166 focus_stack: Vec<FocusId>,
167 focus_parents_by_child: HashMap<FocusId, FocusId>,
168 pub(crate) focus_listeners: Vec<AnyFocusListener>,
169 pub(crate) focus_handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
170 default_prevented: bool,
171 mouse_position: Point<Pixels>,
172 scale_factor: f32,
173 pub(crate) scene_builder: SceneBuilder,
174 pub(crate) dirty: bool,
175 pub(crate) last_blur: Option<Option<FocusId>>,
176 pub(crate) focus: Option<FocusId>,
177}
178
179impl Window {
180 pub(crate) fn new(
181 handle: AnyWindowHandle,
182 options: WindowOptions,
183 cx: &mut MainThread<AppContext>,
184 ) -> Self {
185 let platform_window = cx.platform().open_window(handle, options);
186 let display_id = platform_window.display().id();
187 let sprite_atlas = platform_window.sprite_atlas();
188 let mouse_position = platform_window.mouse_position();
189 let content_size = platform_window.content_size();
190 let scale_factor = platform_window.scale_factor();
191 platform_window.on_resize(Box::new({
192 let cx = cx.to_async();
193 move |content_size, scale_factor| {
194 cx.update_window(handle, |cx| {
195 cx.window.scale_factor = scale_factor;
196 cx.window.scene_builder = SceneBuilder::new();
197 cx.window.content_size = content_size;
198 cx.window.display_id = cx
199 .window
200 .platform_window
201 .borrow_on_main_thread()
202 .display()
203 .id();
204 cx.window.dirty = true;
205 })
206 .log_err();
207 }
208 }));
209
210 platform_window.on_input({
211 let cx = cx.to_async();
212 Box::new(move |event| {
213 cx.update_window(handle, |cx| cx.dispatch_event(event))
214 .log_err()
215 .unwrap_or(true)
216 })
217 });
218
219 let platform_window = MainThreadOnly::new(Arc::new(platform_window), cx.executor.clone());
220
221 Window {
222 handle,
223 platform_window,
224 display_id,
225 sprite_atlas,
226 rem_size: px(16.),
227 content_size,
228 layout_engine: TaffyLayoutEngine::new(),
229 root_view: None,
230 element_id_stack: GlobalElementId::default(),
231 prev_frame_element_states: HashMap::default(),
232 element_states: HashMap::default(),
233 prev_frame_key_matchers: HashMap::default(),
234 key_matchers: HashMap::default(),
235 z_index_stack: StackingOrder(SmallVec::new()),
236 content_mask_stack: Vec::new(),
237 element_offset_stack: Vec::new(),
238 mouse_listeners: HashMap::default(),
239 key_dispatch_stack: Vec::new(),
240 freeze_key_dispatch_stack: false,
241 focus_stack: Vec::new(),
242 focus_parents_by_child: HashMap::default(),
243 focus_listeners: Vec::new(),
244 focus_handles: Arc::new(RwLock::new(SlotMap::with_key())),
245 default_prevented: true,
246 mouse_position,
247 scale_factor,
248 scene_builder: SceneBuilder::new(),
249 dirty: true,
250 last_blur: None,
251 focus: None,
252 }
253 }
254}
255
256enum KeyDispatchStackFrame {
257 Listener {
258 event_type: TypeId,
259 listener: AnyKeyListener,
260 },
261 Context(DispatchContext),
262}
263
264#[derive(Clone, Debug, Default, PartialEq, Eq)]
265#[repr(C)]
266pub struct ContentMask<P: Clone + Default + Debug> {
267 pub bounds: Bounds<P>,
268}
269
270impl ContentMask<Pixels> {
271 pub fn scale(&self, factor: f32) -> ContentMask<ScaledPixels> {
272 ContentMask {
273 bounds: self.bounds.scale(factor),
274 }
275 }
276
277 pub fn intersect(&self, other: &Self) -> Self {
278 let bounds = self.bounds.intersect(&other.bounds);
279 ContentMask { bounds }
280 }
281}
282
283pub struct WindowContext<'a, 'w> {
284 app: Reference<'a, AppContext>,
285 pub(crate) window: Reference<'w, Window>,
286}
287
288impl<'a, 'w> WindowContext<'a, 'w> {
289 pub(crate) fn immutable(app: &'a AppContext, window: &'w Window) -> Self {
290 Self {
291 app: Reference::Immutable(app),
292 window: Reference::Immutable(window),
293 }
294 }
295
296 pub(crate) fn mutable(app: &'a mut AppContext, window: &'w mut Window) -> Self {
297 Self {
298 app: Reference::Mutable(app),
299 window: Reference::Mutable(window),
300 }
301 }
302
303 pub fn window_handle(&self) -> AnyWindowHandle {
304 self.window.handle
305 }
306
307 pub fn notify(&mut self) {
308 self.window.dirty = true;
309 }
310
311 pub fn focus_handle(&mut self) -> FocusHandle {
312 FocusHandle::new(&self.window.focus_handles)
313 }
314
315 pub fn focused(&self) -> Option<FocusHandle> {
316 self.window
317 .focus
318 .and_then(|id| FocusHandle::for_id(id, &self.window.focus_handles))
319 }
320
321 pub fn focus(&mut self, handle: &FocusHandle) {
322 if self.window.last_blur.is_none() {
323 self.window.last_blur = Some(self.window.focus);
324 }
325
326 let window_id = self.window.handle.id;
327 self.window.focus = Some(handle.id);
328 self.app.push_effect(Effect::FocusChanged {
329 window_id,
330 focused: Some(handle.id),
331 });
332 self.notify();
333 }
334
335 pub fn blur(&mut self) {
336 if self.window.last_blur.is_none() {
337 self.window.last_blur = Some(self.window.focus);
338 }
339
340 let window_id = self.window.handle.id;
341 self.window.focus = None;
342 self.app.push_effect(Effect::FocusChanged {
343 window_id,
344 focused: None,
345 });
346 self.notify();
347 }
348
349 pub fn run_on_main<R>(
350 &mut self,
351 f: impl FnOnce(&mut MainThread<WindowContext<'_, '_>>) -> R + Send + 'static,
352 ) -> Task<Result<R>>
353 where
354 R: Send + 'static,
355 {
356 if self.executor.is_main_thread() {
357 Task::ready(Ok(f(unsafe {
358 mem::transmute::<&mut Self, &mut MainThread<Self>>(self)
359 })))
360 } else {
361 let id = self.window.handle.id;
362 self.app.run_on_main(move |cx| cx.update_window(id, f))
363 }
364 }
365
366 pub fn to_async(&self) -> AsyncWindowContext {
367 AsyncWindowContext::new(self.app.to_async(), self.window.handle)
368 }
369
370 pub fn on_next_frame(&mut self, f: impl FnOnce(&mut WindowContext) + Send + 'static) {
371 let f = Box::new(f);
372 let display_id = self.window.display_id;
373 self.run_on_main(move |cx| {
374 if let Some(callbacks) = cx.next_frame_callbacks.get_mut(&display_id) {
375 callbacks.push(f);
376 // If there was already a callback, it means that we already scheduled a frame.
377 if callbacks.len() > 1 {
378 return;
379 }
380 } else {
381 let async_cx = cx.to_async();
382 cx.next_frame_callbacks.insert(display_id, vec![f]);
383 cx.platform().set_display_link_output_callback(
384 display_id,
385 Box::new(move |_current_time, _output_time| {
386 let _ = async_cx.update(|cx| {
387 let callbacks = cx
388 .next_frame_callbacks
389 .get_mut(&display_id)
390 .unwrap()
391 .drain(..)
392 .collect::<Vec<_>>();
393 for callback in callbacks {
394 callback(cx);
395 }
396
397 cx.run_on_main(move |cx| {
398 if cx.next_frame_callbacks.get(&display_id).unwrap().is_empty() {
399 cx.platform().stop_display_link(display_id);
400 }
401 })
402 .detach();
403 });
404 }),
405 );
406 }
407
408 cx.platform().start_display_link(display_id);
409 })
410 .detach();
411 }
412
413 pub fn spawn<Fut, R>(
414 &mut self,
415 f: impl FnOnce(AnyWindowHandle, AsyncWindowContext) -> Fut + Send + 'static,
416 ) -> Task<R>
417 where
418 R: Send + 'static,
419 Fut: Future<Output = R> + Send + 'static,
420 {
421 let window = self.window.handle;
422 self.app.spawn(move |app| {
423 let cx = AsyncWindowContext::new(app, window);
424 let future = f(window, cx);
425 async move { future.await }
426 })
427 }
428
429 pub fn update_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
430 where
431 G: 'static + Send + Sync,
432 {
433 let mut global = self.app.lease_global::<G>();
434 let result = f(global.as_mut(), self);
435 self.app.set_global(global);
436 result
437 }
438
439 pub fn request_layout(
440 &mut self,
441 style: &Style,
442 children: impl IntoIterator<Item = LayoutId>,
443 ) -> LayoutId {
444 self.app.layout_id_buffer.clear();
445 self.app.layout_id_buffer.extend(children.into_iter());
446 let rem_size = self.rem_size();
447
448 self.window
449 .layout_engine
450 .request_layout(style, rem_size, &self.app.layout_id_buffer)
451 }
452
453 pub fn request_measured_layout<
454 F: Fn(Size<Option<Pixels>>, Size<AvailableSpace>) -> Size<Pixels> + Send + Sync + 'static,
455 >(
456 &mut self,
457 style: Style,
458 rem_size: Pixels,
459 measure: F,
460 ) -> LayoutId {
461 self.window
462 .layout_engine
463 .request_measured_layout(style, rem_size, measure)
464 }
465
466 pub fn layout_bounds(&mut self, layout_id: LayoutId) -> Bounds<Pixels> {
467 let mut bounds = self
468 .window
469 .layout_engine
470 .layout_bounds(layout_id)
471 .map(Into::into);
472 bounds.origin += self.element_offset();
473 bounds
474 }
475
476 pub fn scale_factor(&self) -> f32 {
477 self.window.scale_factor
478 }
479
480 pub fn rem_size(&self) -> Pixels {
481 self.window.rem_size
482 }
483
484 pub fn line_height(&self) -> Pixels {
485 let rem_size = self.rem_size();
486 let text_style = self.text_style();
487 text_style
488 .line_height
489 .to_pixels(text_style.font_size.into(), rem_size)
490 }
491
492 pub fn prevent_default(&mut self) {
493 self.window.default_prevented = true;
494 }
495
496 pub fn default_prevented(&self) -> bool {
497 self.window.default_prevented
498 }
499
500 pub fn on_mouse_event<Event: 'static>(
501 &mut self,
502 handler: impl Fn(&Event, DispatchPhase, &mut WindowContext) + Send + Sync + 'static,
503 ) {
504 let order = self.window.z_index_stack.clone();
505 self.window
506 .mouse_listeners
507 .entry(TypeId::of::<Event>())
508 .or_default()
509 .push((
510 order,
511 Arc::new(move |event: &dyn Any, phase, cx| {
512 handler(event.downcast_ref().unwrap(), phase, cx)
513 }),
514 ))
515 }
516
517 pub fn mouse_position(&self) -> Point<Pixels> {
518 self.window.mouse_position
519 }
520
521 pub fn stack<R>(&mut self, order: u32, f: impl FnOnce(&mut Self) -> R) -> R {
522 self.window.z_index_stack.push(order);
523 let result = f(self);
524 self.window.z_index_stack.pop();
525 result
526 }
527
528 pub fn paint_shadows(
529 &mut self,
530 bounds: Bounds<Pixels>,
531 corner_radii: Corners<Pixels>,
532 shadows: &[BoxShadow],
533 ) {
534 let scale_factor = self.scale_factor();
535 let content_mask = self.content_mask();
536 let window = &mut *self.window;
537 for shadow in shadows {
538 let mut shadow_bounds = bounds;
539 shadow_bounds.origin += shadow.offset;
540 shadow_bounds.dilate(shadow.spread_radius);
541 window.scene_builder.insert(
542 &window.z_index_stack,
543 Shadow {
544 order: 0,
545 bounds: shadow_bounds.scale(scale_factor),
546 content_mask: content_mask.scale(scale_factor),
547 corner_radii: corner_radii.scale(scale_factor),
548 color: shadow.color,
549 blur_radius: shadow.blur_radius.scale(scale_factor),
550 },
551 );
552 }
553 }
554
555 pub fn paint_quad(
556 &mut self,
557 bounds: Bounds<Pixels>,
558 corner_radii: Corners<Pixels>,
559 background: impl Into<Hsla>,
560 border_widths: Edges<Pixels>,
561 border_color: impl Into<Hsla>,
562 ) {
563 let scale_factor = self.scale_factor();
564 let content_mask = self.content_mask();
565
566 let window = &mut *self.window;
567 window.scene_builder.insert(
568 &window.z_index_stack,
569 Quad {
570 order: 0,
571 bounds: bounds.scale(scale_factor),
572 content_mask: content_mask.scale(scale_factor),
573 background: background.into(),
574 border_color: border_color.into(),
575 corner_radii: corner_radii.scale(scale_factor),
576 border_widths: border_widths.scale(scale_factor),
577 },
578 );
579 }
580
581 pub fn paint_path(&mut self, mut path: Path<Pixels>, color: impl Into<Hsla>) {
582 let scale_factor = self.scale_factor();
583 let content_mask = self.content_mask();
584 path.content_mask = content_mask;
585 path.color = color.into();
586 let window = &mut *self.window;
587 window
588 .scene_builder
589 .insert(&window.z_index_stack, path.scale(scale_factor));
590 }
591
592 pub fn paint_underline(
593 &mut self,
594 origin: Point<Pixels>,
595 width: Pixels,
596 style: &UnderlineStyle,
597 ) -> Result<()> {
598 let scale_factor = self.scale_factor();
599 let height = if style.wavy {
600 style.thickness * 3.
601 } else {
602 style.thickness
603 };
604 let bounds = Bounds {
605 origin,
606 size: size(width, height),
607 };
608 let content_mask = self.content_mask();
609 let window = &mut *self.window;
610 window.scene_builder.insert(
611 &window.z_index_stack,
612 Underline {
613 order: 0,
614 bounds: bounds.scale(scale_factor),
615 content_mask: content_mask.scale(scale_factor),
616 thickness: style.thickness.scale(scale_factor),
617 color: style.color.unwrap_or_default(),
618 wavy: style.wavy,
619 },
620 );
621 Ok(())
622 }
623
624 pub fn paint_glyph(
625 &mut self,
626 origin: Point<Pixels>,
627 font_id: FontId,
628 glyph_id: GlyphId,
629 font_size: Pixels,
630 color: Hsla,
631 ) -> Result<()> {
632 let scale_factor = self.scale_factor();
633 let glyph_origin = origin.scale(scale_factor);
634 let subpixel_variant = Point {
635 x: (glyph_origin.x.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
636 y: (glyph_origin.y.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
637 };
638 let params = RenderGlyphParams {
639 font_id,
640 glyph_id,
641 font_size,
642 subpixel_variant,
643 scale_factor,
644 is_emoji: false,
645 };
646
647 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
648 if !raster_bounds.is_zero() {
649 let tile =
650 self.window
651 .sprite_atlas
652 .get_or_insert_with(¶ms.clone().into(), &mut || {
653 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
654 Ok((size, Cow::Owned(bytes)))
655 })?;
656 let bounds = Bounds {
657 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
658 size: tile.bounds.size.map(Into::into),
659 };
660 let content_mask = self.content_mask().scale(scale_factor);
661 let window = &mut *self.window;
662 window.scene_builder.insert(
663 &window.z_index_stack,
664 MonochromeSprite {
665 order: 0,
666 bounds,
667 content_mask,
668 color,
669 tile,
670 },
671 );
672 }
673 Ok(())
674 }
675
676 pub fn paint_emoji(
677 &mut self,
678 origin: Point<Pixels>,
679 font_id: FontId,
680 glyph_id: GlyphId,
681 font_size: Pixels,
682 ) -> Result<()> {
683 let scale_factor = self.scale_factor();
684 let glyph_origin = origin.scale(scale_factor);
685 let params = RenderGlyphParams {
686 font_id,
687 glyph_id,
688 font_size,
689 // We don't render emojis with subpixel variants.
690 subpixel_variant: Default::default(),
691 scale_factor,
692 is_emoji: true,
693 };
694
695 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
696 if !raster_bounds.is_zero() {
697 let tile =
698 self.window
699 .sprite_atlas
700 .get_or_insert_with(¶ms.clone().into(), &mut || {
701 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
702 Ok((size, Cow::Owned(bytes)))
703 })?;
704 let bounds = Bounds {
705 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
706 size: tile.bounds.size.map(Into::into),
707 };
708 let content_mask = self.content_mask().scale(scale_factor);
709 let window = &mut *self.window;
710
711 window.scene_builder.insert(
712 &window.z_index_stack,
713 PolychromeSprite {
714 order: 0,
715 bounds,
716 corner_radii: Default::default(),
717 content_mask,
718 tile,
719 grayscale: false,
720 },
721 );
722 }
723 Ok(())
724 }
725
726 pub fn paint_svg(
727 &mut self,
728 bounds: Bounds<Pixels>,
729 path: SharedString,
730 color: Hsla,
731 ) -> Result<()> {
732 let scale_factor = self.scale_factor();
733 let bounds = bounds.scale(scale_factor);
734 // Render the SVG at twice the size to get a higher quality result.
735 let params = RenderSvgParams {
736 path,
737 size: bounds
738 .size
739 .map(|pixels| DevicePixels::from((pixels.0 * 2.).ceil() as i32)),
740 };
741
742 let tile =
743 self.window
744 .sprite_atlas
745 .get_or_insert_with(¶ms.clone().into(), &mut || {
746 let bytes = self.svg_renderer.render(¶ms)?;
747 Ok((params.size, Cow::Owned(bytes)))
748 })?;
749 let content_mask = self.content_mask().scale(scale_factor);
750
751 let window = &mut *self.window;
752 window.scene_builder.insert(
753 &window.z_index_stack,
754 MonochromeSprite {
755 order: 0,
756 bounds,
757 content_mask,
758 color,
759 tile,
760 },
761 );
762
763 Ok(())
764 }
765
766 pub fn paint_image(
767 &mut self,
768 bounds: Bounds<Pixels>,
769 corner_radii: Corners<Pixels>,
770 data: Arc<ImageData>,
771 grayscale: bool,
772 ) -> Result<()> {
773 let scale_factor = self.scale_factor();
774 let bounds = bounds.scale(scale_factor);
775 let params = RenderImageParams { image_id: data.id };
776
777 let tile = self
778 .window
779 .sprite_atlas
780 .get_or_insert_with(¶ms.clone().into(), &mut || {
781 Ok((data.size(), Cow::Borrowed(data.as_bytes())))
782 })?;
783 let content_mask = self.content_mask().scale(scale_factor);
784 let corner_radii = corner_radii.scale(scale_factor);
785
786 let window = &mut *self.window;
787 window.scene_builder.insert(
788 &window.z_index_stack,
789 PolychromeSprite {
790 order: 0,
791 bounds,
792 content_mask,
793 corner_radii,
794 tile,
795 grayscale,
796 },
797 );
798 Ok(())
799 }
800
801 pub(crate) fn draw(&mut self) {
802 let unit_entity = self.unit_entity.clone();
803 self.update_entity(&unit_entity, |view, cx| {
804 cx.start_frame();
805
806 let mut root_view = cx.window.root_view.take().unwrap();
807
808 cx.stack(0, |cx| {
809 let available_space = cx.window.content_size.map(Into::into);
810 draw_any_view(&mut root_view, available_space, cx);
811 });
812
813 if let Some(mut active_drag) = cx.active_drag.take() {
814 cx.stack(1, |cx| {
815 let offset = cx.mouse_position() - active_drag.cursor_offset;
816 cx.with_element_offset(Some(offset), |cx| {
817 let available_space =
818 size(AvailableSpace::MinContent, AvailableSpace::MinContent);
819 draw_any_view(&mut active_drag.drag_handle_view, available_space, cx);
820 cx.active_drag = Some(active_drag);
821 });
822 });
823 }
824
825 cx.window.root_view = Some(root_view);
826 let scene = cx.window.scene_builder.build();
827
828 cx.run_on_main(view, |_, cx| {
829 cx.window
830 .platform_window
831 .borrow_on_main_thread()
832 .draw(scene);
833 cx.window.dirty = false;
834 })
835 .detach();
836 });
837
838 fn draw_any_view(
839 view: &mut AnyView,
840 available_space: Size<AvailableSpace>,
841 cx: &mut ViewContext<()>,
842 ) {
843 cx.with_optional_element_state(view.id(), |element_state, cx| {
844 let mut element_state = view.initialize(&mut (), element_state, cx);
845 let layout_id = view.layout(&mut (), &mut element_state, cx);
846 cx.window
847 .layout_engine
848 .compute_layout(layout_id, available_space);
849 let bounds = cx.window.layout_engine.layout_bounds(layout_id);
850 view.paint(bounds, &mut (), &mut element_state, cx);
851 ((), element_state)
852 });
853 }
854 }
855
856 fn start_frame(&mut self) {
857 self.text_system().start_frame();
858
859 let window = &mut *self.window;
860
861 // Move the current frame element states to the previous frame.
862 // The new empty element states map will be populated for any element states we
863 // reference during the upcoming frame.
864 mem::swap(
865 &mut window.element_states,
866 &mut window.prev_frame_element_states,
867 );
868 window.element_states.clear();
869
870 // Make the current key matchers the previous, and then clear the current.
871 // An empty key matcher map will be created for every identified element in the
872 // upcoming frame.
873 mem::swap(
874 &mut window.key_matchers,
875 &mut window.prev_frame_key_matchers,
876 );
877 window.key_matchers.clear();
878
879 // Clear mouse event listeners, because elements add new element listeners
880 // when the upcoming frame is painted.
881 window.mouse_listeners.values_mut().for_each(Vec::clear);
882
883 // Clear focus state, because we determine what is focused when the new elements
884 // in the upcoming frame are initialized.
885 window.focus_listeners.clear();
886 window.key_dispatch_stack.clear();
887 window.focus_parents_by_child.clear();
888 window.freeze_key_dispatch_stack = false;
889 }
890
891 fn dispatch_event(&mut self, event: InputEvent) -> bool {
892 if let Some(any_mouse_event) = event.mouse_event() {
893 if let Some(MouseMoveEvent { position, .. }) = any_mouse_event.downcast_ref() {
894 self.window.mouse_position = *position;
895 }
896
897 match any_mouse_event.downcast_ref() {
898 Some(FileDropEvent::Pending { position }) => {
899 dbg!("FileDropEvent::Pending", position);
900 return true;
901 }
902 Some(FileDropEvent::Submit { position, paths }) => {
903 dbg!("FileDropEvent::Submit", position, paths);
904 return true;
905 }
906 Some(FileDropEvent::End) => {
907 self.active_drag = None;
908 return true;
909 }
910 _ => {}
911 }
912
913 // Handlers may set this to false by calling `stop_propagation`
914 self.app.propagate_event = true;
915 self.window.default_prevented = false;
916
917 if let Some(mut handlers) = self
918 .window
919 .mouse_listeners
920 .remove(&any_mouse_event.type_id())
921 {
922 // Because handlers may add other handlers, we sort every time.
923 handlers.sort_by(|(a, _), (b, _)| a.cmp(b));
924
925 // Capture phase, events bubble from back to front. Handlers for this phase are used for
926 // special purposes, such as detecting events outside of a given Bounds.
927 for (_, handler) in &handlers {
928 handler(any_mouse_event, DispatchPhase::Capture, self);
929 if !self.app.propagate_event {
930 break;
931 }
932 }
933
934 // Bubble phase, where most normal handlers do their work.
935 if self.app.propagate_event {
936 for (_, handler) in handlers.iter().rev() {
937 handler(any_mouse_event, DispatchPhase::Bubble, self);
938 if !self.app.propagate_event {
939 break;
940 }
941 }
942 }
943
944 if self.app.propagate_event
945 && any_mouse_event.downcast_ref::<MouseUpEvent>().is_some()
946 {
947 self.active_drag = None;
948 }
949
950 // Just in case any handlers added new handlers, which is weird, but possible.
951 handlers.extend(
952 self.window
953 .mouse_listeners
954 .get_mut(&any_mouse_event.type_id())
955 .into_iter()
956 .flat_map(|handlers| handlers.drain(..)),
957 );
958 self.window
959 .mouse_listeners
960 .insert(any_mouse_event.type_id(), handlers);
961 }
962 } else if let Some(any_key_event) = event.keyboard_event() {
963 let key_dispatch_stack = mem::take(&mut self.window.key_dispatch_stack);
964 let key_event_type = any_key_event.type_id();
965 let mut context_stack = SmallVec::<[&DispatchContext; 16]>::new();
966
967 for (ix, frame) in key_dispatch_stack.iter().enumerate() {
968 match frame {
969 KeyDispatchStackFrame::Listener {
970 event_type,
971 listener,
972 } => {
973 if key_event_type == *event_type {
974 if let Some(action) = listener(
975 any_key_event,
976 &context_stack,
977 DispatchPhase::Capture,
978 self,
979 ) {
980 self.dispatch_action(action, &key_dispatch_stack[..ix]);
981 }
982 if !self.app.propagate_event {
983 break;
984 }
985 }
986 }
987 KeyDispatchStackFrame::Context(context) => {
988 context_stack.push(&context);
989 }
990 }
991 }
992
993 if self.app.propagate_event {
994 for (ix, frame) in key_dispatch_stack.iter().enumerate().rev() {
995 match frame {
996 KeyDispatchStackFrame::Listener {
997 event_type,
998 listener,
999 } => {
1000 if key_event_type == *event_type {
1001 if let Some(action) = listener(
1002 any_key_event,
1003 &context_stack,
1004 DispatchPhase::Bubble,
1005 self,
1006 ) {
1007 self.dispatch_action(action, &key_dispatch_stack[..ix]);
1008 }
1009
1010 if !self.app.propagate_event {
1011 break;
1012 }
1013 }
1014 }
1015 KeyDispatchStackFrame::Context(_) => {
1016 context_stack.pop();
1017 }
1018 }
1019 }
1020 }
1021
1022 drop(context_stack);
1023 self.window.key_dispatch_stack = key_dispatch_stack;
1024 }
1025
1026 true
1027 }
1028
1029 pub fn match_keystroke(
1030 &mut self,
1031 element_id: &GlobalElementId,
1032 keystroke: &Keystroke,
1033 context_stack: &[&DispatchContext],
1034 ) -> KeyMatch {
1035 let key_match = self
1036 .window
1037 .key_matchers
1038 .get_mut(element_id)
1039 .unwrap()
1040 .match_keystroke(keystroke, context_stack);
1041
1042 if key_match.is_some() {
1043 for matcher in self.window.key_matchers.values_mut() {
1044 matcher.clear_pending();
1045 }
1046 }
1047
1048 key_match
1049 }
1050
1051 pub fn observe_global<G: 'static>(
1052 &mut self,
1053 f: impl Fn(&mut WindowContext<'_, '_>) + Send + Sync + 'static,
1054 ) -> Subscription {
1055 let window_id = self.window.handle.id;
1056 self.global_observers.insert(
1057 TypeId::of::<G>(),
1058 Box::new(move |cx| cx.update_window(window_id, |cx| f(cx)).is_ok()),
1059 )
1060 }
1061
1062 fn dispatch_action(
1063 &mut self,
1064 action: Box<dyn Action>,
1065 dispatch_stack: &[KeyDispatchStackFrame],
1066 ) {
1067 let action_type = action.as_any().type_id();
1068
1069 if let Some(mut global_listeners) = self.app.global_action_listeners.remove(&action_type) {
1070 for listener in &global_listeners {
1071 listener(action.as_ref(), DispatchPhase::Capture, self);
1072 if !self.app.propagate_event {
1073 break;
1074 }
1075 }
1076 global_listeners.extend(
1077 self.global_action_listeners
1078 .remove(&action_type)
1079 .unwrap_or_default(),
1080 );
1081 self.global_action_listeners
1082 .insert(action_type, global_listeners);
1083 }
1084
1085 if self.app.propagate_event {
1086 for stack_frame in dispatch_stack {
1087 if let KeyDispatchStackFrame::Listener {
1088 event_type,
1089 listener,
1090 } = stack_frame
1091 {
1092 if action_type == *event_type {
1093 listener(action.as_any(), &[], DispatchPhase::Capture, self);
1094 if !self.app.propagate_event {
1095 break;
1096 }
1097 }
1098 }
1099 }
1100 }
1101
1102 if self.app.propagate_event {
1103 for stack_frame in dispatch_stack.iter().rev() {
1104 if let KeyDispatchStackFrame::Listener {
1105 event_type,
1106 listener,
1107 } = stack_frame
1108 {
1109 if action_type == *event_type {
1110 listener(action.as_any(), &[], DispatchPhase::Bubble, self);
1111 if !self.app.propagate_event {
1112 break;
1113 }
1114 }
1115 }
1116 }
1117 }
1118
1119 if self.app.propagate_event {
1120 if let Some(mut global_listeners) =
1121 self.app.global_action_listeners.remove(&action_type)
1122 {
1123 for listener in global_listeners.iter().rev() {
1124 listener(action.as_ref(), DispatchPhase::Bubble, self);
1125 if !self.app.propagate_event {
1126 break;
1127 }
1128 }
1129 global_listeners.extend(
1130 self.global_action_listeners
1131 .remove(&action_type)
1132 .unwrap_or_default(),
1133 );
1134 self.global_action_listeners
1135 .insert(action_type, global_listeners);
1136 }
1137 }
1138 }
1139}
1140
1141impl Context for WindowContext<'_, '_> {
1142 type EntityContext<'a, 'w, T: 'static + Send + Sync> = ViewContext<'a, 'w, T>;
1143 type Result<T> = T;
1144
1145 fn entity<T: Send + Sync + 'static>(
1146 &mut self,
1147 build_entity: impl FnOnce(&mut Self::EntityContext<'_, '_, T>) -> T,
1148 ) -> Handle<T> {
1149 let slot = self.app.entities.reserve();
1150 let entity = build_entity(&mut ViewContext::mutable(
1151 &mut *self.app,
1152 &mut self.window,
1153 slot.entity_id,
1154 ));
1155 self.entities.insert(slot, entity)
1156 }
1157
1158 fn update_entity<T: Send + Sync + 'static, R>(
1159 &mut self,
1160 handle: &Handle<T>,
1161 update: impl FnOnce(&mut T, &mut Self::EntityContext<'_, '_, T>) -> R,
1162 ) -> R {
1163 let mut entity = self.entities.lease(handle);
1164 let result = update(
1165 &mut *entity,
1166 &mut ViewContext::mutable(&mut *self.app, &mut *self.window, handle.entity_id),
1167 );
1168 self.entities.end_lease(entity);
1169 result
1170 }
1171}
1172
1173impl<'a, 'w> std::ops::Deref for WindowContext<'a, 'w> {
1174 type Target = AppContext;
1175
1176 fn deref(&self) -> &Self::Target {
1177 &self.app
1178 }
1179}
1180
1181impl<'a, 'w> std::ops::DerefMut for WindowContext<'a, 'w> {
1182 fn deref_mut(&mut self) -> &mut Self::Target {
1183 &mut self.app
1184 }
1185}
1186
1187impl<'a, 'w> Borrow<AppContext> for WindowContext<'a, 'w> {
1188 fn borrow(&self) -> &AppContext {
1189 &self.app
1190 }
1191}
1192
1193impl<'a, 'w> BorrowMut<AppContext> for WindowContext<'a, 'w> {
1194 fn borrow_mut(&mut self) -> &mut AppContext {
1195 &mut self.app
1196 }
1197}
1198
1199pub trait BorrowWindow: BorrowMut<Window> + BorrowMut<AppContext> {
1200 fn app_mut(&mut self) -> &mut AppContext {
1201 self.borrow_mut()
1202 }
1203
1204 fn window(&self) -> &Window {
1205 self.borrow()
1206 }
1207
1208 fn window_mut(&mut self) -> &mut Window {
1209 self.borrow_mut()
1210 }
1211
1212 fn with_element_id<R>(
1213 &mut self,
1214 id: impl Into<ElementId>,
1215 f: impl FnOnce(GlobalElementId, &mut Self) -> R,
1216 ) -> R {
1217 let keymap = self.app_mut().keymap.clone();
1218 let window = self.window_mut();
1219 window.element_id_stack.push(id.into());
1220 let global_id = window.element_id_stack.clone();
1221
1222 if window.key_matchers.get(&global_id).is_none() {
1223 window.key_matchers.insert(
1224 global_id.clone(),
1225 window
1226 .prev_frame_key_matchers
1227 .remove(&global_id)
1228 .unwrap_or_else(|| KeyMatcher::new(keymap)),
1229 );
1230 }
1231
1232 let result = f(global_id, self);
1233 let window: &mut Window = self.borrow_mut();
1234 window.element_id_stack.pop();
1235 result
1236 }
1237
1238 fn with_content_mask<R>(
1239 &mut self,
1240 mask: ContentMask<Pixels>,
1241 f: impl FnOnce(&mut Self) -> R,
1242 ) -> R {
1243 let mask = mask.intersect(&self.content_mask());
1244 self.window_mut().content_mask_stack.push(mask);
1245 let result = f(self);
1246 self.window_mut().content_mask_stack.pop();
1247 result
1248 }
1249
1250 fn with_element_offset<R>(
1251 &mut self,
1252 offset: Option<Point<Pixels>>,
1253 f: impl FnOnce(&mut Self) -> R,
1254 ) -> R {
1255 let Some(offset) = offset else {
1256 return f(self);
1257 };
1258
1259 let offset = self.element_offset() + offset;
1260 self.window_mut().element_offset_stack.push(offset);
1261 let result = f(self);
1262 self.window_mut().element_offset_stack.pop();
1263 result
1264 }
1265
1266 fn element_offset(&self) -> Point<Pixels> {
1267 self.window()
1268 .element_offset_stack
1269 .last()
1270 .copied()
1271 .unwrap_or_default()
1272 }
1273
1274 fn with_element_state<S: 'static + Send + Sync, R>(
1275 &mut self,
1276 id: ElementId,
1277 f: impl FnOnce(Option<S>, &mut Self) -> (R, S),
1278 ) -> R {
1279 self.with_element_id(id, |global_id, cx| {
1280 if let Some(any) = cx
1281 .window_mut()
1282 .element_states
1283 .remove(&global_id)
1284 .or_else(|| cx.window_mut().prev_frame_element_states.remove(&global_id))
1285 {
1286 // Using the extra inner option to avoid needing to reallocate a new box.
1287 let mut state_box = any
1288 .downcast::<Option<S>>()
1289 .expect("invalid element state type for id");
1290 let state = state_box
1291 .take()
1292 .expect("element state is already on the stack");
1293 let (result, state) = f(Some(state), cx);
1294 state_box.replace(state);
1295 cx.window_mut().element_states.insert(global_id, state_box);
1296 result
1297 } else {
1298 let (result, state) = f(None, cx);
1299 cx.window_mut()
1300 .element_states
1301 .insert(global_id, Box::new(Some(state)));
1302 result
1303 }
1304 })
1305 }
1306
1307 fn with_optional_element_state<S: 'static + Send + Sync, R>(
1308 &mut self,
1309 element_id: Option<ElementId>,
1310 f: impl FnOnce(Option<S>, &mut Self) -> (R, S),
1311 ) -> R {
1312 if let Some(element_id) = element_id {
1313 self.with_element_state(element_id, f)
1314 } else {
1315 f(None, self).0
1316 }
1317 }
1318
1319 fn content_mask(&self) -> ContentMask<Pixels> {
1320 self.window()
1321 .content_mask_stack
1322 .last()
1323 .cloned()
1324 .unwrap_or_else(|| ContentMask {
1325 bounds: Bounds {
1326 origin: Point::default(),
1327 size: self.window().content_size,
1328 },
1329 })
1330 }
1331
1332 fn rem_size(&self) -> Pixels {
1333 self.window().rem_size
1334 }
1335}
1336
1337impl Borrow<Window> for WindowContext<'_, '_> {
1338 fn borrow(&self) -> &Window {
1339 &self.window
1340 }
1341}
1342
1343impl BorrowMut<Window> for WindowContext<'_, '_> {
1344 fn borrow_mut(&mut self) -> &mut Window {
1345 &mut self.window
1346 }
1347}
1348
1349impl<T> BorrowWindow for T where T: BorrowMut<AppContext> + BorrowMut<Window> {}
1350
1351pub struct ViewContext<'a, 'w, V> {
1352 window_cx: WindowContext<'a, 'w>,
1353 entity_type: PhantomData<V>,
1354 entity_id: EntityId,
1355}
1356
1357impl<V> Borrow<AppContext> for ViewContext<'_, '_, V> {
1358 fn borrow(&self) -> &AppContext {
1359 &*self.window_cx.app
1360 }
1361}
1362
1363impl<V> BorrowMut<AppContext> for ViewContext<'_, '_, V> {
1364 fn borrow_mut(&mut self) -> &mut AppContext {
1365 &mut *self.window_cx.app
1366 }
1367}
1368
1369impl<V> Borrow<Window> for ViewContext<'_, '_, V> {
1370 fn borrow(&self) -> &Window {
1371 &*self.window_cx.window
1372 }
1373}
1374
1375impl<V> BorrowMut<Window> for ViewContext<'_, '_, V> {
1376 fn borrow_mut(&mut self) -> &mut Window {
1377 &mut *self.window_cx.window
1378 }
1379}
1380
1381impl<'a, 'w, V: Send + Sync + 'static> ViewContext<'a, 'w, V> {
1382 fn mutable(app: &'a mut AppContext, window: &'w mut Window, entity_id: EntityId) -> Self {
1383 Self {
1384 window_cx: WindowContext::mutable(app, window),
1385 entity_id,
1386 entity_type: PhantomData,
1387 }
1388 }
1389
1390 pub fn handle(&self) -> WeakHandle<V> {
1391 self.entities.weak_handle(self.entity_id)
1392 }
1393
1394 pub fn stack<R>(&mut self, order: u32, f: impl FnOnce(&mut Self) -> R) -> R {
1395 self.window.z_index_stack.push(order);
1396 let result = f(self);
1397 self.window.z_index_stack.pop();
1398 result
1399 }
1400
1401 pub fn on_next_frame(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + Send + 'static) {
1402 let entity = self.handle();
1403 self.window_cx.on_next_frame(move |cx| {
1404 entity.update(cx, f).ok();
1405 });
1406 }
1407
1408 pub fn observe<E: Send + Sync + 'static>(
1409 &mut self,
1410 handle: &Handle<E>,
1411 on_notify: impl Fn(&mut V, Handle<E>, &mut ViewContext<'_, '_, V>) + Send + Sync + 'static,
1412 ) -> Subscription {
1413 let this = self.handle();
1414 let handle = handle.downgrade();
1415 let window_handle = self.window.handle;
1416 self.app.observers.insert(
1417 handle.entity_id,
1418 Box::new(move |cx| {
1419 cx.update_window(window_handle.id, |cx| {
1420 if let Some(handle) = handle.upgrade() {
1421 this.update(cx, |this, cx| on_notify(this, handle, cx))
1422 .is_ok()
1423 } else {
1424 false
1425 }
1426 })
1427 .unwrap_or(false)
1428 }),
1429 )
1430 }
1431
1432 pub fn subscribe<E: EventEmitter + Send + Sync + 'static>(
1433 &mut self,
1434 handle: &Handle<E>,
1435 on_event: impl Fn(&mut V, Handle<E>, &E::Event, &mut ViewContext<'_, '_, V>)
1436 + Send
1437 + Sync
1438 + 'static,
1439 ) -> Subscription {
1440 let this = self.handle();
1441 let handle = handle.downgrade();
1442 let window_handle = self.window.handle;
1443 self.app.event_listeners.insert(
1444 handle.entity_id,
1445 Box::new(move |event, cx| {
1446 cx.update_window(window_handle.id, |cx| {
1447 if let Some(handle) = handle.upgrade() {
1448 let event = event.downcast_ref().expect("invalid event type");
1449 this.update(cx, |this, cx| on_event(this, handle, event, cx))
1450 .is_ok()
1451 } else {
1452 false
1453 }
1454 })
1455 .unwrap_or(false)
1456 }),
1457 )
1458 }
1459
1460 pub fn on_release(
1461 &mut self,
1462 on_release: impl Fn(&mut V, &mut WindowContext) + Send + Sync + 'static,
1463 ) -> Subscription {
1464 let window_handle = self.window.handle;
1465 self.app.release_listeners.insert(
1466 self.entity_id,
1467 Box::new(move |this, cx| {
1468 let this = this.downcast_mut().expect("invalid entity type");
1469 // todo!("are we okay with silently swallowing the error?")
1470 let _ = cx.update_window(window_handle.id, |cx| on_release(this, cx));
1471 }),
1472 )
1473 }
1474
1475 pub fn observe_release<E: Send + Sync + 'static>(
1476 &mut self,
1477 handle: &Handle<E>,
1478 on_release: impl Fn(&mut V, &mut E, &mut ViewContext<'_, '_, V>) + Send + Sync + 'static,
1479 ) -> Subscription {
1480 let this = self.handle();
1481 let window_handle = self.window.handle;
1482 self.app.release_listeners.insert(
1483 handle.entity_id,
1484 Box::new(move |entity, cx| {
1485 let entity = entity.downcast_mut().expect("invalid entity type");
1486 // todo!("are we okay with silently swallowing the error?")
1487 let _ = cx.update_window(window_handle.id, |cx| {
1488 this.update(cx, |this, cx| on_release(this, entity, cx))
1489 });
1490 }),
1491 )
1492 }
1493
1494 pub fn notify(&mut self) {
1495 self.window_cx.notify();
1496 self.window_cx.app.push_effect(Effect::Notify {
1497 emitter: self.entity_id,
1498 });
1499 }
1500
1501 pub fn on_focus_changed(
1502 &mut self,
1503 listener: impl Fn(&mut V, &FocusEvent, &mut ViewContext<V>) + Send + Sync + 'static,
1504 ) {
1505 let handle = self.handle();
1506 self.window.focus_listeners.push(Arc::new(move |event, cx| {
1507 handle
1508 .update(cx, |view, cx| listener(view, event, cx))
1509 .log_err();
1510 }));
1511 }
1512
1513 pub fn with_key_listeners<R>(
1514 &mut self,
1515 key_listeners: &[(TypeId, KeyListener<V>)],
1516 f: impl FnOnce(&mut Self) -> R,
1517 ) -> R {
1518 if !self.window.freeze_key_dispatch_stack {
1519 for (event_type, listener) in key_listeners.iter().cloned() {
1520 let handle = self.handle();
1521 let listener = Arc::new(
1522 move |event: &dyn Any,
1523 context_stack: &[&DispatchContext],
1524 phase: DispatchPhase,
1525 cx: &mut WindowContext<'_, '_>| {
1526 handle
1527 .update(cx, |view, cx| {
1528 listener(view, event, context_stack, phase, cx)
1529 })
1530 .log_err()
1531 .flatten()
1532 },
1533 );
1534 self.window
1535 .key_dispatch_stack
1536 .push(KeyDispatchStackFrame::Listener {
1537 event_type,
1538 listener,
1539 });
1540 }
1541 }
1542
1543 let result = f(self);
1544
1545 if !self.window.freeze_key_dispatch_stack {
1546 let prev_len = self.window.key_dispatch_stack.len() - key_listeners.len();
1547 self.window.key_dispatch_stack.truncate(prev_len);
1548 }
1549
1550 result
1551 }
1552
1553 pub fn with_key_dispatch_context<R>(
1554 &mut self,
1555 context: DispatchContext,
1556 f: impl FnOnce(&mut Self) -> R,
1557 ) -> R {
1558 if context.is_empty() {
1559 return f(self);
1560 }
1561
1562 if !self.window.freeze_key_dispatch_stack {
1563 self.window
1564 .key_dispatch_stack
1565 .push(KeyDispatchStackFrame::Context(context));
1566 }
1567
1568 let result = f(self);
1569
1570 if !self.window.freeze_key_dispatch_stack {
1571 self.window.key_dispatch_stack.pop();
1572 }
1573
1574 result
1575 }
1576
1577 pub fn with_focus<R>(
1578 &mut self,
1579 focus_handle: FocusHandle,
1580 f: impl FnOnce(&mut Self) -> R,
1581 ) -> R {
1582 if let Some(parent_focus_id) = self.window.focus_stack.last().copied() {
1583 self.window
1584 .focus_parents_by_child
1585 .insert(focus_handle.id, parent_focus_id);
1586 }
1587 self.window.focus_stack.push(focus_handle.id);
1588
1589 if Some(focus_handle.id) == self.window.focus {
1590 self.window.freeze_key_dispatch_stack = true;
1591 }
1592
1593 let result = f(self);
1594
1595 self.window.focus_stack.pop();
1596 result
1597 }
1598
1599 pub fn run_on_main<R>(
1600 &mut self,
1601 view: &mut V,
1602 f: impl FnOnce(&mut V, &mut MainThread<ViewContext<'_, '_, V>>) -> R + Send + 'static,
1603 ) -> Task<Result<R>>
1604 where
1605 R: Send + 'static,
1606 {
1607 if self.executor.is_main_thread() {
1608 let cx = unsafe { mem::transmute::<&mut Self, &mut MainThread<Self>>(self) };
1609 Task::ready(Ok(f(view, cx)))
1610 } else {
1611 let handle = self.handle().upgrade().unwrap();
1612 self.window_cx.run_on_main(move |cx| handle.update(cx, f))
1613 }
1614 }
1615
1616 pub fn spawn<Fut, R>(
1617 &mut self,
1618 f: impl FnOnce(WeakHandle<V>, AsyncWindowContext) -> Fut + Send + 'static,
1619 ) -> Task<R>
1620 where
1621 R: Send + 'static,
1622 Fut: Future<Output = R> + Send + 'static,
1623 {
1624 let handle = self.handle();
1625 self.window_cx.spawn(move |_, cx| {
1626 let result = f(handle, cx);
1627 async move { result.await }
1628 })
1629 }
1630
1631 pub fn update_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
1632 where
1633 G: 'static + Send + Sync,
1634 {
1635 let mut global = self.app.lease_global::<G>();
1636 let result = f(global.as_mut(), self);
1637 self.app.restore_global(global);
1638 result
1639 }
1640
1641 pub fn observe_global<G: 'static>(
1642 &mut self,
1643 f: impl Fn(&mut V, &mut ViewContext<'_, '_, V>) + Send + Sync + 'static,
1644 ) -> Subscription {
1645 let window_id = self.window.handle.id;
1646 let handle = self.handle();
1647 self.global_observers.insert(
1648 TypeId::of::<G>(),
1649 Box::new(move |cx| {
1650 cx.update_window(window_id, |cx| {
1651 handle.update(cx, |view, cx| f(view, cx)).is_ok()
1652 })
1653 .unwrap_or(false)
1654 }),
1655 )
1656 }
1657
1658 pub fn on_mouse_event<Event: 'static>(
1659 &mut self,
1660 handler: impl Fn(&mut V, &Event, DispatchPhase, &mut ViewContext<V>) + Send + Sync + 'static,
1661 ) {
1662 let handle = self.handle().upgrade().unwrap();
1663 self.window_cx.on_mouse_event(move |event, phase, cx| {
1664 handle.update(cx, |view, cx| {
1665 handler(view, event, phase, cx);
1666 })
1667 });
1668 }
1669}
1670
1671impl<'a, 'w, V: EventEmitter + Send + Sync + 'static> ViewContext<'a, 'w, V> {
1672 pub fn emit(&mut self, event: V::Event) {
1673 let emitter = self.entity_id;
1674 self.app.push_effect(Effect::Emit {
1675 emitter,
1676 event: Box::new(event),
1677 });
1678 }
1679}
1680
1681impl<'a, 'w, V> Context for ViewContext<'a, 'w, V>
1682where
1683 V: 'static + Send + Sync,
1684{
1685 type EntityContext<'b, 'c, U: 'static + Send + Sync> = ViewContext<'b, 'c, U>;
1686 type Result<U> = U;
1687
1688 fn entity<T2: Send + Sync + 'static>(
1689 &mut self,
1690 build_entity: impl FnOnce(&mut Self::EntityContext<'_, '_, T2>) -> T2,
1691 ) -> Handle<T2> {
1692 self.window_cx.entity(build_entity)
1693 }
1694
1695 fn update_entity<U: 'static + Send + Sync, R>(
1696 &mut self,
1697 handle: &Handle<U>,
1698 update: impl FnOnce(&mut U, &mut Self::EntityContext<'_, '_, U>) -> R,
1699 ) -> R {
1700 self.window_cx.update_entity(handle, update)
1701 }
1702}
1703
1704impl<'a, 'w, S: 'static> std::ops::Deref for ViewContext<'a, 'w, S> {
1705 type Target = WindowContext<'a, 'w>;
1706
1707 fn deref(&self) -> &Self::Target {
1708 &self.window_cx
1709 }
1710}
1711
1712impl<'a, 'w, S: 'static> std::ops::DerefMut for ViewContext<'a, 'w, S> {
1713 fn deref_mut(&mut self) -> &mut Self::Target {
1714 &mut self.window_cx
1715 }
1716}
1717
1718// #[derive(Clone, Copy, Eq, PartialEq, Hash)]
1719slotmap::new_key_type! { pub struct WindowId; }
1720
1721impl WindowId {
1722 pub fn as_u64(&self) -> u64 {
1723 self.0.as_ffi()
1724 }
1725}
1726
1727#[derive(PartialEq, Eq)]
1728pub struct WindowHandle<S> {
1729 id: WindowId,
1730 state_type: PhantomData<S>,
1731}
1732
1733impl<S> Copy for WindowHandle<S> {}
1734
1735impl<S> Clone for WindowHandle<S> {
1736 fn clone(&self) -> Self {
1737 WindowHandle {
1738 id: self.id,
1739 state_type: PhantomData,
1740 }
1741 }
1742}
1743
1744impl<S> WindowHandle<S> {
1745 pub fn new(id: WindowId) -> Self {
1746 WindowHandle {
1747 id,
1748 state_type: PhantomData,
1749 }
1750 }
1751}
1752
1753impl<S: 'static> Into<AnyWindowHandle> for WindowHandle<S> {
1754 fn into(self) -> AnyWindowHandle {
1755 AnyWindowHandle {
1756 id: self.id,
1757 state_type: TypeId::of::<S>(),
1758 }
1759 }
1760}
1761
1762#[derive(Copy, Clone, PartialEq, Eq)]
1763pub struct AnyWindowHandle {
1764 pub(crate) id: WindowId,
1765 state_type: TypeId,
1766}
1767
1768impl AnyWindowHandle {
1769 pub fn window_id(&self) -> WindowId {
1770 self.id
1771 }
1772}
1773
1774#[cfg(any(test, feature = "test"))]
1775impl From<SmallVec<[u32; 16]>> for StackingOrder {
1776 fn from(small_vec: SmallVec<[u32; 16]>) -> Self {
1777 StackingOrder(small_vec)
1778 }
1779}
1780
1781#[derive(Clone, Debug, Eq, PartialEq, Hash)]
1782pub enum ElementId {
1783 View(EntityId),
1784 Number(usize),
1785 Name(SharedString),
1786 FocusHandle(FocusId),
1787}
1788
1789impl From<EntityId> for ElementId {
1790 fn from(id: EntityId) -> Self {
1791 ElementId::View(id)
1792 }
1793}
1794
1795impl From<usize> for ElementId {
1796 fn from(id: usize) -> Self {
1797 ElementId::Number(id)
1798 }
1799}
1800
1801impl From<i32> for ElementId {
1802 fn from(id: i32) -> Self {
1803 Self::Number(id as usize)
1804 }
1805}
1806
1807impl From<SharedString> for ElementId {
1808 fn from(name: SharedString) -> Self {
1809 ElementId::Name(name)
1810 }
1811}
1812
1813impl From<&'static str> for ElementId {
1814 fn from(name: &'static str) -> Self {
1815 ElementId::Name(name.into())
1816 }
1817}
1818
1819impl<'a> From<&'a FocusHandle> for ElementId {
1820 fn from(handle: &'a FocusHandle) -> Self {
1821 ElementId::FocusHandle(handle.id)
1822 }
1823}