1use crate::{
2 key_dispatch::DispatchActionListener, px, size, transparent_black, Action, AnyDrag, AnyView,
3 AppContext, AsyncWindowContext, AvailableSpace, Bounds, BoxShadow, Context, Corners,
4 CursorStyle, DevicePixels, DispatchNodeId, DispatchTree, DisplayId, Edges, Effect, Entity,
5 EntityId, EventEmitter, FileDropEvent, Flatten, FocusEvent, FontId, GlobalElementId, GlyphId,
6 Hsla, ImageData, InputEvent, IsZero, KeyBinding, KeyContext, KeyDownEvent, KeystrokeEvent,
7 LayoutId, Model, ModelContext, Modifiers, MonochromeSprite, MouseButton, MouseMoveEvent,
8 MouseUpEvent, Path, Pixels, PlatformAtlas, PlatformDisplay, PlatformInputHandler,
9 PlatformWindow, Point, PolychromeSprite, PromptLevel, Quad, Render, RenderGlyphParams,
10 RenderImageParams, RenderSvgParams, ScaledPixels, Scene, SceneBuilder, Shadow, SharedString,
11 Size, Style, SubscriberSet, Subscription, Surface, TaffyLayoutEngine, Task, Underline,
12 UnderlineStyle, View, VisualContext, WeakView, WindowBounds, WindowOptions, SUBPIXEL_VARIANTS,
13};
14use anyhow::{anyhow, Context as _, Result};
15use collections::HashMap;
16use derive_more::{Deref, DerefMut};
17use futures::{
18 channel::{mpsc, oneshot},
19 StreamExt,
20};
21use media::core_video::CVImageBuffer;
22use parking_lot::RwLock;
23use slotmap::SlotMap;
24use smallvec::SmallVec;
25use std::{
26 any::{Any, TypeId},
27 borrow::{Borrow, BorrowMut, Cow},
28 fmt::Debug,
29 future::Future,
30 hash::{Hash, Hasher},
31 marker::PhantomData,
32 mem,
33 rc::Rc,
34 sync::{
35 atomic::{AtomicUsize, Ordering::SeqCst},
36 Arc,
37 },
38};
39use util::ResultExt;
40
41const ACTIVE_DRAG_Z_INDEX: u32 = 1;
42
43/// A global stacking order, which is created by stacking successive z-index values.
44/// Each z-index will always be interpreted in the context of its parent z-index.
45#[derive(Deref, DerefMut, Ord, PartialOrd, Eq, PartialEq, Clone, Default, Debug)]
46pub struct StackingOrder(pub(crate) SmallVec<[u32; 16]>);
47
48/// Represents the two different phases when dispatching events.
49#[derive(Default, Copy, Clone, Debug, Eq, PartialEq)]
50pub enum DispatchPhase {
51 /// After the capture phase comes the bubble phase, in which mouse event listeners are
52 /// invoked front to back and keyboard event listeners are invoked from the focused element
53 /// to the root of the element tree. This is the phase you'll most commonly want to use when
54 /// registering event listeners.
55 #[default]
56 Bubble,
57 /// During the initial capture phase, mouse event listeners are invoked back to front, and keyboard
58 /// listeners are invoked from the root of the tree downward toward the focused element. This phase
59 /// is used for special purposes such as clearing the "pressed" state for click events. If
60 /// you stop event propagation during this phase, you need to know what you're doing. Handlers
61 /// outside of the immediate region may rely on detecting non-local events during this phase.
62 Capture,
63}
64
65impl DispatchPhase {
66 pub fn bubble(self) -> bool {
67 self == DispatchPhase::Bubble
68 }
69
70 pub fn capture(self) -> bool {
71 self == DispatchPhase::Capture
72 }
73}
74
75type AnyObserver = Box<dyn FnMut(&mut WindowContext) -> bool + 'static>;
76type AnyMouseListener = Box<dyn FnMut(&dyn Any, DispatchPhase, &mut WindowContext) + 'static>;
77type AnyFocusListener = Box<dyn Fn(&FocusEvent, &mut WindowContext) + 'static>;
78type AnyWindowFocusListener = Box<dyn FnMut(&FocusEvent, &mut WindowContext) -> bool + 'static>;
79
80slotmap::new_key_type! { pub struct FocusId; }
81
82impl FocusId {
83 /// Obtains whether the element associated with this handle is currently focused.
84 pub fn is_focused(&self, cx: &WindowContext) -> bool {
85 cx.window.focus == Some(*self)
86 }
87
88 /// Obtains whether the element associated with this handle contains the focused
89 /// element or is itself focused.
90 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
91 cx.focused()
92 .map_or(false, |focused| self.contains(focused.id, cx))
93 }
94
95 /// Obtains whether the element associated with this handle is contained within the
96 /// focused element or is itself focused.
97 pub fn within_focused(&self, cx: &WindowContext) -> bool {
98 let focused = cx.focused();
99 focused.map_or(false, |focused| focused.id.contains(*self, cx))
100 }
101
102 /// Obtains whether this handle contains the given handle in the most recently rendered frame.
103 pub(crate) fn contains(&self, other: Self, cx: &WindowContext) -> bool {
104 cx.window
105 .rendered_frame
106 .dispatch_tree
107 .focus_contains(*self, other)
108 }
109}
110
111/// A handle which can be used to track and manipulate the focused element in a window.
112pub struct FocusHandle {
113 pub(crate) id: FocusId,
114 handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
115}
116
117impl std::fmt::Debug for FocusHandle {
118 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
119 f.write_fmt(format_args!("FocusHandle({:?})", self.id))
120 }
121}
122
123impl FocusHandle {
124 pub(crate) fn new(handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>) -> Self {
125 let id = handles.write().insert(AtomicUsize::new(1));
126 Self {
127 id,
128 handles: handles.clone(),
129 }
130 }
131
132 pub(crate) fn for_id(
133 id: FocusId,
134 handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
135 ) -> Option<Self> {
136 let lock = handles.read();
137 let ref_count = lock.get(id)?;
138 if ref_count.load(SeqCst) == 0 {
139 None
140 } else {
141 ref_count.fetch_add(1, SeqCst);
142 Some(Self {
143 id,
144 handles: handles.clone(),
145 })
146 }
147 }
148
149 /// Moves the focus to the element associated with this handle.
150 pub fn focus(&self, cx: &mut WindowContext) {
151 cx.focus(self)
152 }
153
154 /// Obtains whether the element associated with this handle is currently focused.
155 pub fn is_focused(&self, cx: &WindowContext) -> bool {
156 self.id.is_focused(cx)
157 }
158
159 /// Obtains whether the element associated with this handle contains the focused
160 /// element or is itself focused.
161 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
162 self.id.contains_focused(cx)
163 }
164
165 /// Obtains whether the element associated with this handle is contained within the
166 /// focused element or is itself focused.
167 pub fn within_focused(&self, cx: &WindowContext) -> bool {
168 self.id.within_focused(cx)
169 }
170
171 /// Obtains whether this handle contains the given handle in the most recently rendered frame.
172 pub fn contains(&self, other: &Self, cx: &WindowContext) -> bool {
173 self.id.contains(other.id, cx)
174 }
175}
176
177impl Clone for FocusHandle {
178 fn clone(&self) -> Self {
179 Self::for_id(self.id, &self.handles).unwrap()
180 }
181}
182
183impl PartialEq for FocusHandle {
184 fn eq(&self, other: &Self) -> bool {
185 self.id == other.id
186 }
187}
188
189impl Eq for FocusHandle {}
190
191impl Drop for FocusHandle {
192 fn drop(&mut self) {
193 self.handles
194 .read()
195 .get(self.id)
196 .unwrap()
197 .fetch_sub(1, SeqCst);
198 }
199}
200
201/// FocusableView allows users of your view to easily
202/// focus it (using cx.focus_view(view))
203pub trait FocusableView: 'static + Render {
204 fn focus_handle(&self, cx: &AppContext) -> FocusHandle;
205}
206
207/// ManagedView is a view (like a Modal, Popover, Menu, etc.)
208/// where the lifecycle of the view is handled by another view.
209pub trait ManagedView: FocusableView + EventEmitter<DismissEvent> {}
210
211impl<M: FocusableView + EventEmitter<DismissEvent>> ManagedView for M {}
212
213pub struct DismissEvent;
214
215// Holds the state for a specific window.
216pub struct Window {
217 pub(crate) handle: AnyWindowHandle,
218 pub(crate) removed: bool,
219 pub(crate) platform_window: Box<dyn PlatformWindow>,
220 display_id: DisplayId,
221 sprite_atlas: Arc<dyn PlatformAtlas>,
222 rem_size: Pixels,
223 viewport_size: Size<Pixels>,
224 layout_engine: Option<TaffyLayoutEngine>,
225 pub(crate) root_view: Option<AnyView>,
226 pub(crate) element_id_stack: GlobalElementId,
227 pub(crate) rendered_frame: Frame,
228 pub(crate) next_frame: Frame,
229 pub(crate) focus_handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
230 pub(crate) focus_listeners: SubscriberSet<(), AnyWindowFocusListener>,
231 pub(crate) blur_listeners: SubscriberSet<(), AnyObserver>,
232 default_prevented: bool,
233 mouse_position: Point<Pixels>,
234 modifiers: Modifiers,
235 requested_cursor_style: Option<CursorStyle>,
236 scale_factor: f32,
237 bounds: WindowBounds,
238 bounds_observers: SubscriberSet<(), AnyObserver>,
239 active: bool,
240 pub(crate) dirty: bool,
241 activation_observers: SubscriberSet<(), AnyObserver>,
242 pub(crate) last_blur: Option<Option<FocusId>>,
243 pub(crate) focus: Option<FocusId>,
244}
245
246pub(crate) struct ElementStateBox {
247 inner: Box<dyn Any>,
248 #[cfg(debug_assertions)]
249 type_name: &'static str,
250}
251
252// #[derive(Default)]
253pub(crate) struct Frame {
254 pub(crate) element_states: HashMap<GlobalElementId, ElementStateBox>,
255 mouse_listeners: HashMap<TypeId, Vec<(StackingOrder, AnyMouseListener)>>,
256 pub(crate) dispatch_tree: DispatchTree,
257 pub(crate) focus_listeners: Vec<AnyFocusListener>,
258 pub(crate) scene_builder: SceneBuilder,
259 pub(crate) depth_map: Vec<(StackingOrder, Bounds<Pixels>)>,
260 pub(crate) z_index_stack: StackingOrder,
261 content_mask_stack: Vec<ContentMask<Pixels>>,
262 element_offset_stack: Vec<Point<Pixels>>,
263}
264
265impl Frame {
266 fn new(dispatch_tree: DispatchTree) -> Self {
267 Frame {
268 element_states: HashMap::default(),
269 mouse_listeners: HashMap::default(),
270 dispatch_tree,
271 focus_listeners: Vec::new(),
272 scene_builder: SceneBuilder::default(),
273 z_index_stack: StackingOrder::default(),
274 depth_map: Default::default(),
275 content_mask_stack: Vec::new(),
276 element_offset_stack: Vec::new(),
277 }
278 }
279
280 fn clear(&mut self) {
281 self.element_states.clear();
282 self.mouse_listeners.values_mut().for_each(Vec::clear);
283 self.focus_listeners.clear();
284 self.dispatch_tree.clear();
285 self.depth_map.clear();
286 }
287}
288
289impl Window {
290 pub(crate) fn new(
291 handle: AnyWindowHandle,
292 options: WindowOptions,
293 cx: &mut AppContext,
294 ) -> Self {
295 let platform_window = cx.platform.open_window(
296 handle,
297 options,
298 Box::new({
299 let mut cx = cx.to_async();
300 move || handle.update(&mut cx, |_, cx| cx.draw())
301 }),
302 );
303 let display_id = platform_window.display().id();
304 let sprite_atlas = platform_window.sprite_atlas();
305 let mouse_position = platform_window.mouse_position();
306 let modifiers = platform_window.modifiers();
307 let content_size = platform_window.content_size();
308 let scale_factor = platform_window.scale_factor();
309 let bounds = platform_window.bounds();
310
311 platform_window.on_resize(Box::new({
312 let mut cx = cx.to_async();
313 move |_, _| {
314 handle
315 .update(&mut cx, |_, cx| cx.window_bounds_changed())
316 .log_err();
317 }
318 }));
319 platform_window.on_moved(Box::new({
320 let mut cx = cx.to_async();
321 move || {
322 handle
323 .update(&mut cx, |_, cx| cx.window_bounds_changed())
324 .log_err();
325 }
326 }));
327 platform_window.on_active_status_change(Box::new({
328 let mut cx = cx.to_async();
329 move |active| {
330 handle
331 .update(&mut cx, |_, cx| {
332 cx.window.active = active;
333 cx.window
334 .activation_observers
335 .clone()
336 .retain(&(), |callback| callback(cx));
337 })
338 .log_err();
339 }
340 }));
341
342 platform_window.on_input({
343 let mut cx = cx.to_async();
344 Box::new(move |event| {
345 handle
346 .update(&mut cx, |_, cx| cx.dispatch_event(event))
347 .log_err()
348 .unwrap_or(false)
349 })
350 });
351
352 Window {
353 handle,
354 removed: false,
355 platform_window,
356 display_id,
357 sprite_atlas,
358 rem_size: px(16.),
359 viewport_size: content_size,
360 layout_engine: Some(TaffyLayoutEngine::new()),
361 root_view: None,
362 element_id_stack: GlobalElementId::default(),
363 rendered_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
364 next_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
365 focus_handles: Arc::new(RwLock::new(SlotMap::with_key())),
366 focus_listeners: SubscriberSet::new(),
367 blur_listeners: SubscriberSet::new(),
368 default_prevented: true,
369 mouse_position,
370 modifiers,
371 requested_cursor_style: None,
372 scale_factor,
373 bounds,
374 bounds_observers: SubscriberSet::new(),
375 active: false,
376 dirty: false,
377 activation_observers: SubscriberSet::new(),
378 last_blur: None,
379 focus: None,
380 }
381 }
382}
383
384/// Indicates which region of the window is visible. Content falling outside of this mask will not be
385/// rendered. Currently, only rectangular content masks are supported, but we give the mask its own type
386/// to leave room to support more complex shapes in the future.
387#[derive(Clone, Debug, Default, PartialEq, Eq)]
388#[repr(C)]
389pub struct ContentMask<P: Clone + Default + Debug> {
390 pub bounds: Bounds<P>,
391}
392
393impl ContentMask<Pixels> {
394 /// Scale the content mask's pixel units by the given scaling factor.
395 pub fn scale(&self, factor: f32) -> ContentMask<ScaledPixels> {
396 ContentMask {
397 bounds: self.bounds.scale(factor),
398 }
399 }
400
401 /// Intersect the content mask with the given content mask.
402 pub fn intersect(&self, other: &Self) -> Self {
403 let bounds = self.bounds.intersect(&other.bounds);
404 ContentMask { bounds }
405 }
406}
407
408/// Provides access to application state in the context of a single window. Derefs
409/// to an `AppContext`, so you can also pass a `WindowContext` to any method that takes
410/// an `AppContext` and call any `AppContext` methods.
411pub struct WindowContext<'a> {
412 pub(crate) app: &'a mut AppContext,
413 pub(crate) window: &'a mut Window,
414}
415
416impl<'a> WindowContext<'a> {
417 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window) -> Self {
418 Self { app, window }
419 }
420
421 /// Obtain a handle to the window that belongs to this context.
422 pub fn window_handle(&self) -> AnyWindowHandle {
423 self.window.handle
424 }
425
426 /// Mark the window as dirty, scheduling it to be redrawn on the next frame.
427 pub fn notify(&mut self) {
428 self.window.dirty = true;
429 }
430
431 /// Close this window.
432 pub fn remove_window(&mut self) {
433 self.window.removed = true;
434 }
435
436 /// Obtain a new `FocusHandle`, which allows you to track and manipulate the keyboard focus
437 /// for elements rendered within this window.
438 pub fn focus_handle(&mut self) -> FocusHandle {
439 FocusHandle::new(&self.window.focus_handles)
440 }
441
442 /// Obtain the currently focused `FocusHandle`. If no elements are focused, returns `None`.
443 pub fn focused(&self) -> Option<FocusHandle> {
444 self.window
445 .focus
446 .and_then(|id| FocusHandle::for_id(id, &self.window.focus_handles))
447 }
448
449 /// Move focus to the element associated with the given `FocusHandle`.
450 pub fn focus(&mut self, handle: &FocusHandle) {
451 if self.window.focus == Some(handle.id) {
452 return;
453 }
454
455 let focus_id = handle.id;
456
457 if self.window.last_blur.is_none() {
458 self.window.last_blur = Some(self.window.focus);
459 }
460
461 self.window.focus = Some(focus_id);
462 self.window
463 .rendered_frame
464 .dispatch_tree
465 .clear_pending_keystrokes();
466 self.app.push_effect(Effect::FocusChanged {
467 window_handle: self.window.handle,
468 focused: Some(focus_id),
469 });
470 self.notify();
471 }
472
473 /// Remove focus from all elements within this context's window.
474 pub fn blur(&mut self) {
475 if self.window.last_blur.is_none() {
476 self.window.last_blur = Some(self.window.focus);
477 }
478
479 self.window.focus = None;
480 self.app.push_effect(Effect::FocusChanged {
481 window_handle: self.window.handle,
482 focused: None,
483 });
484 self.notify();
485 }
486
487 pub fn dispatch_action(&mut self, action: Box<dyn Action>) {
488 let focus_handle = self.focused();
489
490 self.defer(move |cx| {
491 let node_id = focus_handle
492 .and_then(|handle| {
493 cx.window
494 .rendered_frame
495 .dispatch_tree
496 .focusable_node_id(handle.id)
497 })
498 .unwrap_or_else(|| cx.window.rendered_frame.dispatch_tree.root_node_id());
499
500 cx.propagate_event = true;
501 cx.dispatch_action_on_node(node_id, action);
502 })
503 }
504
505 pub(crate) fn dispatch_keystroke_observers(
506 &mut self,
507 event: &dyn Any,
508 action: Option<Box<dyn Action>>,
509 ) {
510 let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() else {
511 return;
512 };
513
514 self.keystroke_observers
515 .clone()
516 .retain(&(), move |callback| {
517 (callback)(
518 &KeystrokeEvent {
519 keystroke: key_down_event.keystroke.clone(),
520 action: action.as_ref().map(|action| action.boxed_clone()),
521 },
522 self,
523 );
524 true
525 });
526 }
527
528 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
529 /// that are currently on the stack to be returned to the app.
530 pub fn defer(&mut self, f: impl FnOnce(&mut WindowContext) + 'static) {
531 let handle = self.window.handle;
532 self.app.defer(move |cx| {
533 handle.update(cx, |_, cx| f(cx)).ok();
534 });
535 }
536
537 pub fn subscribe<Emitter, E, Evt>(
538 &mut self,
539 entity: &E,
540 mut on_event: impl FnMut(E, &Evt, &mut WindowContext<'_>) + 'static,
541 ) -> Subscription
542 where
543 Emitter: EventEmitter<Evt>,
544 E: Entity<Emitter>,
545 Evt: 'static,
546 {
547 let entity_id = entity.entity_id();
548 let entity = entity.downgrade();
549 let window_handle = self.window.handle;
550 let (subscription, activate) = self.app.event_listeners.insert(
551 entity_id,
552 (
553 TypeId::of::<Evt>(),
554 Box::new(move |event, cx| {
555 window_handle
556 .update(cx, |_, cx| {
557 if let Some(handle) = E::upgrade_from(&entity) {
558 let event = event.downcast_ref().expect("invalid event type");
559 on_event(handle, event, cx);
560 true
561 } else {
562 false
563 }
564 })
565 .unwrap_or(false)
566 }),
567 ),
568 );
569 self.app.defer(move |_| activate());
570 subscription
571 }
572
573 /// Create an `AsyncWindowContext`, which has a static lifetime and can be held across
574 /// await points in async code.
575 pub fn to_async(&self) -> AsyncWindowContext {
576 AsyncWindowContext::new(self.app.to_async(), self.window.handle)
577 }
578
579 /// Schedule the given closure to be run directly after the current frame is rendered.
580 pub fn on_next_frame(&mut self, callback: impl FnOnce(&mut WindowContext) + 'static) {
581 let handle = self.window.handle;
582 let display_id = self.window.display_id;
583
584 if !self.frame_consumers.contains_key(&display_id) {
585 let (tx, mut rx) = mpsc::unbounded::<()>();
586 self.platform.set_display_link_output_callback(
587 display_id,
588 Box::new(move |_current_time, _output_time| _ = tx.unbounded_send(())),
589 );
590
591 let consumer_task = self.app.spawn(|cx| async move {
592 while rx.next().await.is_some() {
593 cx.update(|cx| {
594 for callback in cx
595 .next_frame_callbacks
596 .get_mut(&display_id)
597 .unwrap()
598 .drain(..)
599 .collect::<SmallVec<[_; 32]>>()
600 {
601 callback(cx);
602 }
603 })
604 .ok();
605
606 // Flush effects, then stop the display link if no new next_frame_callbacks have been added.
607
608 cx.update(|cx| {
609 if cx.next_frame_callbacks.is_empty() {
610 cx.platform.stop_display_link(display_id);
611 }
612 })
613 .ok();
614 }
615 });
616 self.frame_consumers.insert(display_id, consumer_task);
617 }
618
619 if self.next_frame_callbacks.is_empty() {
620 self.platform.start_display_link(display_id);
621 }
622
623 self.next_frame_callbacks
624 .entry(display_id)
625 .or_default()
626 .push(Box::new(move |cx: &mut AppContext| {
627 cx.update_window(handle, |_root_view, cx| callback(cx)).ok();
628 }));
629 }
630
631 /// Spawn the future returned by the given closure on the application thread pool.
632 /// The closure is provided a handle to the current window and an `AsyncWindowContext` for
633 /// use within your future.
634 pub fn spawn<Fut, R>(&mut self, f: impl FnOnce(AsyncWindowContext) -> Fut) -> Task<R>
635 where
636 R: 'static,
637 Fut: Future<Output = R> + 'static,
638 {
639 self.app
640 .spawn(|app| f(AsyncWindowContext::new(app, self.window.handle)))
641 }
642
643 /// Update the global of the given type. The given closure is given simultaneous mutable
644 /// access both to the global and the context.
645 pub fn update_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
646 where
647 G: 'static,
648 {
649 let mut global = self.app.lease_global::<G>();
650 let result = f(&mut global, self);
651 self.app.end_global_lease(global);
652 result
653 }
654
655 #[must_use]
656 /// Add a node to the layout tree for the current frame. Takes the `Style` of the element for which
657 /// layout is being requested, along with the layout ids of any children. This method is called during
658 /// calls to the `Element::layout` trait method and enables any element to participate in layout.
659 pub fn request_layout(
660 &mut self,
661 style: &Style,
662 children: impl IntoIterator<Item = LayoutId>,
663 ) -> LayoutId {
664 self.app.layout_id_buffer.clear();
665 self.app.layout_id_buffer.extend(children.into_iter());
666 let rem_size = self.rem_size();
667
668 self.window.layout_engine.as_mut().unwrap().request_layout(
669 style,
670 rem_size,
671 &self.app.layout_id_buffer,
672 )
673 }
674
675 /// Add a node to the layout tree for the current frame. Instead of taking a `Style` and children,
676 /// this variant takes a function that is invoked during layout so you can use arbitrary logic to
677 /// determine the element's size. One place this is used internally is when measuring text.
678 ///
679 /// The given closure is invoked at layout time with the known dimensions and available space and
680 /// returns a `Size`.
681 pub fn request_measured_layout<
682 F: FnMut(Size<Option<Pixels>>, Size<AvailableSpace>, &mut WindowContext) -> Size<Pixels>
683 + 'static,
684 >(
685 &mut self,
686 style: Style,
687 measure: F,
688 ) -> LayoutId {
689 let rem_size = self.rem_size();
690 self.window
691 .layout_engine
692 .as_mut()
693 .unwrap()
694 .request_measured_layout(style, rem_size, measure)
695 }
696
697 pub fn compute_layout(&mut self, layout_id: LayoutId, available_space: Size<AvailableSpace>) {
698 let mut layout_engine = self.window.layout_engine.take().unwrap();
699 layout_engine.compute_layout(layout_id, available_space, self);
700 self.window.layout_engine = Some(layout_engine);
701 }
702
703 /// Obtain the bounds computed for the given LayoutId relative to the window. This method should not
704 /// be invoked until the paint phase begins, and will usually be invoked by GPUI itself automatically
705 /// in order to pass your element its `Bounds` automatically.
706 pub fn layout_bounds(&mut self, layout_id: LayoutId) -> Bounds<Pixels> {
707 let mut bounds = self
708 .window
709 .layout_engine
710 .as_mut()
711 .unwrap()
712 .layout_bounds(layout_id)
713 .map(Into::into);
714 bounds.origin += self.element_offset();
715 bounds
716 }
717
718 fn window_bounds_changed(&mut self) {
719 self.window.scale_factor = self.window.platform_window.scale_factor();
720 self.window.viewport_size = self.window.platform_window.content_size();
721 self.window.bounds = self.window.platform_window.bounds();
722 self.window.display_id = self.window.platform_window.display().id();
723 self.notify();
724
725 self.window
726 .bounds_observers
727 .clone()
728 .retain(&(), |callback| callback(self));
729 }
730
731 pub fn window_bounds(&self) -> WindowBounds {
732 self.window.bounds
733 }
734
735 pub fn viewport_size(&self) -> Size<Pixels> {
736 self.window.viewport_size
737 }
738
739 pub fn is_window_active(&self) -> bool {
740 self.window.active
741 }
742
743 pub fn zoom_window(&self) {
744 self.window.platform_window.zoom();
745 }
746
747 pub fn set_window_title(&mut self, title: &str) {
748 self.window.platform_window.set_title(title);
749 }
750
751 pub fn display(&self) -> Option<Rc<dyn PlatformDisplay>> {
752 self.platform
753 .displays()
754 .into_iter()
755 .find(|display| display.id() == self.window.display_id)
756 }
757
758 pub fn show_character_palette(&self) {
759 self.window.platform_window.show_character_palette();
760 }
761
762 /// The scale factor of the display associated with the window. For example, it could
763 /// return 2.0 for a "retina" display, indicating that each logical pixel should actually
764 /// be rendered as two pixels on screen.
765 pub fn scale_factor(&self) -> f32 {
766 self.window.scale_factor
767 }
768
769 /// The size of an em for the base font of the application. Adjusting this value allows the
770 /// UI to scale, just like zooming a web page.
771 pub fn rem_size(&self) -> Pixels {
772 self.window.rem_size
773 }
774
775 /// Sets the size of an em for the base font of the application. Adjusting this value allows the
776 /// UI to scale, just like zooming a web page.
777 pub fn set_rem_size(&mut self, rem_size: impl Into<Pixels>) {
778 self.window.rem_size = rem_size.into();
779 }
780
781 /// The line height associated with the current text style.
782 pub fn line_height(&self) -> Pixels {
783 let rem_size = self.rem_size();
784 let text_style = self.text_style();
785 text_style
786 .line_height
787 .to_pixels(text_style.font_size.into(), rem_size)
788 }
789
790 /// Call to prevent the default action of an event. Currently only used to prevent
791 /// parent elements from becoming focused on mouse down.
792 pub fn prevent_default(&mut self) {
793 self.window.default_prevented = true;
794 }
795
796 /// Obtain whether default has been prevented for the event currently being dispatched.
797 pub fn default_prevented(&self) -> bool {
798 self.window.default_prevented
799 }
800
801 /// Register a mouse event listener on the window for the next frame. The type of event
802 /// is determined by the first parameter of the given listener. When the next frame is rendered
803 /// the listener will be cleared.
804 ///
805 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
806 /// a specific need to register a global listener.
807 pub fn on_mouse_event<Event: 'static>(
808 &mut self,
809 mut handler: impl FnMut(&Event, DispatchPhase, &mut WindowContext) + 'static,
810 ) {
811 let order = self.window.next_frame.z_index_stack.clone();
812 self.window
813 .next_frame
814 .mouse_listeners
815 .entry(TypeId::of::<Event>())
816 .or_default()
817 .push((
818 order,
819 Box::new(move |event: &dyn Any, phase, cx| {
820 handler(event.downcast_ref().unwrap(), phase, cx)
821 }),
822 ))
823 }
824
825 /// Register a key event listener on the window for the next frame. The type of event
826 /// is determined by the first parameter of the given listener. When the next frame is rendered
827 /// the listener will be cleared.
828 ///
829 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
830 /// a specific need to register a global listener.
831 pub fn on_key_event<Event: 'static>(
832 &mut self,
833 handler: impl Fn(&Event, DispatchPhase, &mut WindowContext) + 'static,
834 ) {
835 self.window
836 .next_frame
837 .dispatch_tree
838 .on_key_event(Rc::new(move |event, phase, cx| {
839 if let Some(event) = event.downcast_ref::<Event>() {
840 handler(event, phase, cx)
841 }
842 }));
843 }
844
845 /// Register an action listener on the window for the next frame. The type of action
846 /// is determined by the first parameter of the given listener. When the next frame is rendered
847 /// the listener will be cleared.
848 ///
849 /// This is a fairly low-level method, so prefer using action handlers on elements unless you have
850 /// a specific need to register a global listener.
851 pub fn on_action(
852 &mut self,
853 action_type: TypeId,
854 handler: impl Fn(&dyn Any, DispatchPhase, &mut WindowContext) + 'static,
855 ) {
856 self.window.next_frame.dispatch_tree.on_action(
857 action_type,
858 Rc::new(move |action, phase, cx| handler(action, phase, cx)),
859 );
860 }
861
862 pub fn is_action_available(&self, action: &dyn Action) -> bool {
863 let target = self
864 .focused()
865 .and_then(|focused_handle| {
866 self.window
867 .rendered_frame
868 .dispatch_tree
869 .focusable_node_id(focused_handle.id)
870 })
871 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
872 self.window
873 .rendered_frame
874 .dispatch_tree
875 .is_action_available(action, target)
876 }
877
878 /// The position of the mouse relative to the window.
879 pub fn mouse_position(&self) -> Point<Pixels> {
880 self.window.mouse_position
881 }
882
883 /// The current state of the keyboard's modifiers
884 pub fn modifiers(&self) -> Modifiers {
885 self.window.modifiers
886 }
887
888 pub fn set_cursor_style(&mut self, style: CursorStyle) {
889 self.window.requested_cursor_style = Some(style)
890 }
891
892 /// Called during painting to invoke the given closure in a new stacking context. The given
893 /// z-index is interpreted relative to the previous call to `stack`.
894 pub fn with_z_index<R>(&mut self, z_index: u32, f: impl FnOnce(&mut Self) -> R) -> R {
895 self.window.next_frame.z_index_stack.push(z_index);
896 let result = f(self);
897 self.window.next_frame.z_index_stack.pop();
898 result
899 }
900
901 /// Called during painting to track which z-index is on top at each pixel position
902 pub fn add_opaque_layer(&mut self, bounds: Bounds<Pixels>) {
903 let stacking_order = self.window.next_frame.z_index_stack.clone();
904 let depth_map = &mut self.window.next_frame.depth_map;
905 match depth_map.binary_search_by(|(level, _)| stacking_order.cmp(&level)) {
906 Ok(i) | Err(i) => depth_map.insert(i, (stacking_order, bounds)),
907 }
908 }
909
910 /// Returns true if the top-most opaque layer painted over this point was part of the
911 /// same layer as the given stacking order.
912 pub fn was_top_layer(&self, point: &Point<Pixels>, level: &StackingOrder) -> bool {
913 for (stack, bounds) in self.window.rendered_frame.depth_map.iter() {
914 if bounds.contains(point) {
915 return level.starts_with(stack) || stack.starts_with(level);
916 }
917 }
918
919 false
920 }
921
922 pub fn was_top_layer_under_active_drag(
923 &self,
924 point: &Point<Pixels>,
925 level: &StackingOrder,
926 ) -> bool {
927 for (stack, bounds) in self.window.rendered_frame.depth_map.iter() {
928 if stack.starts_with(&[ACTIVE_DRAG_Z_INDEX]) {
929 continue;
930 }
931 if bounds.contains(point) {
932 return level.starts_with(stack) || stack.starts_with(level);
933 }
934 }
935
936 false
937 }
938
939 /// Called during painting to get the current stacking order.
940 pub fn stacking_order(&self) -> &StackingOrder {
941 &self.window.next_frame.z_index_stack
942 }
943
944 /// Paint one or more drop shadows into the scene for the next frame at the current z-index.
945 pub fn paint_shadows(
946 &mut self,
947 bounds: Bounds<Pixels>,
948 corner_radii: Corners<Pixels>,
949 shadows: &[BoxShadow],
950 ) {
951 let scale_factor = self.scale_factor();
952 let content_mask = self.content_mask();
953 let window = &mut *self.window;
954 for shadow in shadows {
955 let mut shadow_bounds = bounds;
956 shadow_bounds.origin += shadow.offset;
957 shadow_bounds.dilate(shadow.spread_radius);
958 window.next_frame.scene_builder.insert(
959 &window.next_frame.z_index_stack,
960 Shadow {
961 order: 0,
962 bounds: shadow_bounds.scale(scale_factor),
963 content_mask: content_mask.scale(scale_factor),
964 corner_radii: corner_radii.scale(scale_factor),
965 color: shadow.color,
966 blur_radius: shadow.blur_radius.scale(scale_factor),
967 },
968 );
969 }
970 }
971
972 /// Paint one or more quads into the scene for the next frame at the current stacking context.
973 /// Quads are colored rectangular regions with an optional background, border, and corner radius.
974 /// see [`fill`], [`outline`], and [`quad`] to construct this type.
975 pub fn paint_quad(&mut self, quad: PaintQuad) {
976 let scale_factor = self.scale_factor();
977 let content_mask = self.content_mask();
978
979 let window = &mut *self.window;
980 window.next_frame.scene_builder.insert(
981 &window.next_frame.z_index_stack,
982 Quad {
983 order: 0,
984 bounds: quad.bounds.scale(scale_factor),
985 content_mask: content_mask.scale(scale_factor),
986 background: quad.background,
987 border_color: quad.border_color,
988 corner_radii: quad.corner_radii.scale(scale_factor),
989 border_widths: quad.border_widths.scale(scale_factor),
990 },
991 );
992 }
993
994 /// Paint the given `Path` into the scene for the next frame at the current z-index.
995 pub fn paint_path(&mut self, mut path: Path<Pixels>, color: impl Into<Hsla>) {
996 let scale_factor = self.scale_factor();
997 let content_mask = self.content_mask();
998 path.content_mask = content_mask;
999 path.color = color.into();
1000 let window = &mut *self.window;
1001 window
1002 .next_frame
1003 .scene_builder
1004 .insert(&window.next_frame.z_index_stack, path.scale(scale_factor));
1005 }
1006
1007 /// Paint an underline into the scene for the next frame at the current z-index.
1008 pub fn paint_underline(
1009 &mut self,
1010 origin: Point<Pixels>,
1011 width: Pixels,
1012 style: &UnderlineStyle,
1013 ) {
1014 let scale_factor = self.scale_factor();
1015 let height = if style.wavy {
1016 style.thickness * 3.
1017 } else {
1018 style.thickness
1019 };
1020 let bounds = Bounds {
1021 origin,
1022 size: size(width, height),
1023 };
1024 let content_mask = self.content_mask();
1025 let window = &mut *self.window;
1026 window.next_frame.scene_builder.insert(
1027 &window.next_frame.z_index_stack,
1028 Underline {
1029 order: 0,
1030 bounds: bounds.scale(scale_factor),
1031 content_mask: content_mask.scale(scale_factor),
1032 thickness: style.thickness.scale(scale_factor),
1033 color: style.color.unwrap_or_default(),
1034 wavy: style.wavy,
1035 },
1036 );
1037 }
1038
1039 /// Paint a monochrome (non-emoji) glyph into the scene for the next frame at the current z-index.
1040 /// The y component of the origin is the baseline of the glyph.
1041 pub fn paint_glyph(
1042 &mut self,
1043 origin: Point<Pixels>,
1044 font_id: FontId,
1045 glyph_id: GlyphId,
1046 font_size: Pixels,
1047 color: Hsla,
1048 ) -> Result<()> {
1049 let scale_factor = self.scale_factor();
1050 let glyph_origin = origin.scale(scale_factor);
1051 let subpixel_variant = Point {
1052 x: (glyph_origin.x.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
1053 y: (glyph_origin.y.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
1054 };
1055 let params = RenderGlyphParams {
1056 font_id,
1057 glyph_id,
1058 font_size,
1059 subpixel_variant,
1060 scale_factor,
1061 is_emoji: false,
1062 };
1063
1064 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
1065 if !raster_bounds.is_zero() {
1066 let tile =
1067 self.window
1068 .sprite_atlas
1069 .get_or_insert_with(¶ms.clone().into(), &mut || {
1070 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
1071 Ok((size, Cow::Owned(bytes)))
1072 })?;
1073 let bounds = Bounds {
1074 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
1075 size: tile.bounds.size.map(Into::into),
1076 };
1077 let content_mask = self.content_mask().scale(scale_factor);
1078 let window = &mut *self.window;
1079 window.next_frame.scene_builder.insert(
1080 &window.next_frame.z_index_stack,
1081 MonochromeSprite {
1082 order: 0,
1083 bounds,
1084 content_mask,
1085 color,
1086 tile,
1087 },
1088 );
1089 }
1090 Ok(())
1091 }
1092
1093 /// Paint an emoji glyph into the scene for the next frame at the current z-index.
1094 /// The y component of the origin is the baseline of the glyph.
1095 pub fn paint_emoji(
1096 &mut self,
1097 origin: Point<Pixels>,
1098 font_id: FontId,
1099 glyph_id: GlyphId,
1100 font_size: Pixels,
1101 ) -> Result<()> {
1102 let scale_factor = self.scale_factor();
1103 let glyph_origin = origin.scale(scale_factor);
1104 let params = RenderGlyphParams {
1105 font_id,
1106 glyph_id,
1107 font_size,
1108 // We don't render emojis with subpixel variants.
1109 subpixel_variant: Default::default(),
1110 scale_factor,
1111 is_emoji: true,
1112 };
1113
1114 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
1115 if !raster_bounds.is_zero() {
1116 let tile =
1117 self.window
1118 .sprite_atlas
1119 .get_or_insert_with(¶ms.clone().into(), &mut || {
1120 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
1121 Ok((size, Cow::Owned(bytes)))
1122 })?;
1123 let bounds = Bounds {
1124 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
1125 size: tile.bounds.size.map(Into::into),
1126 };
1127 let content_mask = self.content_mask().scale(scale_factor);
1128 let window = &mut *self.window;
1129
1130 window.next_frame.scene_builder.insert(
1131 &window.next_frame.z_index_stack,
1132 PolychromeSprite {
1133 order: 0,
1134 bounds,
1135 corner_radii: Default::default(),
1136 content_mask,
1137 tile,
1138 grayscale: false,
1139 },
1140 );
1141 }
1142 Ok(())
1143 }
1144
1145 /// Paint a monochrome SVG into the scene for the next frame at the current stacking context.
1146 pub fn paint_svg(
1147 &mut self,
1148 bounds: Bounds<Pixels>,
1149 path: SharedString,
1150 color: Hsla,
1151 ) -> Result<()> {
1152 let scale_factor = self.scale_factor();
1153 let bounds = bounds.scale(scale_factor);
1154 // Render the SVG at twice the size to get a higher quality result.
1155 let params = RenderSvgParams {
1156 path,
1157 size: bounds
1158 .size
1159 .map(|pixels| DevicePixels::from((pixels.0 * 2.).ceil() as i32)),
1160 };
1161
1162 let tile =
1163 self.window
1164 .sprite_atlas
1165 .get_or_insert_with(¶ms.clone().into(), &mut || {
1166 let bytes = self.svg_renderer.render(¶ms)?;
1167 Ok((params.size, Cow::Owned(bytes)))
1168 })?;
1169 let content_mask = self.content_mask().scale(scale_factor);
1170
1171 let window = &mut *self.window;
1172 window.next_frame.scene_builder.insert(
1173 &window.next_frame.z_index_stack,
1174 MonochromeSprite {
1175 order: 0,
1176 bounds,
1177 content_mask,
1178 color,
1179 tile,
1180 },
1181 );
1182
1183 Ok(())
1184 }
1185
1186 /// Paint an image into the scene for the next frame at the current z-index.
1187 pub fn paint_image(
1188 &mut self,
1189 bounds: Bounds<Pixels>,
1190 corner_radii: Corners<Pixels>,
1191 data: Arc<ImageData>,
1192 grayscale: bool,
1193 ) -> Result<()> {
1194 let scale_factor = self.scale_factor();
1195 let bounds = bounds.scale(scale_factor);
1196 let params = RenderImageParams { image_id: data.id };
1197
1198 let tile = self
1199 .window
1200 .sprite_atlas
1201 .get_or_insert_with(¶ms.clone().into(), &mut || {
1202 Ok((data.size(), Cow::Borrowed(data.as_bytes())))
1203 })?;
1204 let content_mask = self.content_mask().scale(scale_factor);
1205 let corner_radii = corner_radii.scale(scale_factor);
1206
1207 let window = &mut *self.window;
1208 window.next_frame.scene_builder.insert(
1209 &window.next_frame.z_index_stack,
1210 PolychromeSprite {
1211 order: 0,
1212 bounds,
1213 content_mask,
1214 corner_radii,
1215 tile,
1216 grayscale,
1217 },
1218 );
1219 Ok(())
1220 }
1221
1222 /// Paint a surface into the scene for the next frame at the current z-index.
1223 pub fn paint_surface(&mut self, bounds: Bounds<Pixels>, image_buffer: CVImageBuffer) {
1224 let scale_factor = self.scale_factor();
1225 let bounds = bounds.scale(scale_factor);
1226 let content_mask = self.content_mask().scale(scale_factor);
1227 let window = &mut *self.window;
1228 window.next_frame.scene_builder.insert(
1229 &window.next_frame.z_index_stack,
1230 Surface {
1231 order: 0,
1232 bounds,
1233 content_mask,
1234 image_buffer,
1235 },
1236 );
1237 }
1238
1239 /// Draw pixels to the display for this window based on the contents of its scene.
1240 pub(crate) fn draw(&mut self) -> Scene {
1241 let window_was_focused = self
1242 .window
1243 .focus
1244 .and_then(|focus_id| {
1245 self.window
1246 .rendered_frame
1247 .dispatch_tree
1248 .focusable_node_id(focus_id)
1249 })
1250 .is_some();
1251 self.text_system().start_frame();
1252 self.window.platform_window.clear_input_handler();
1253 self.window.layout_engine.as_mut().unwrap().clear();
1254 self.window.next_frame.clear();
1255 let root_view = self.window.root_view.take().unwrap();
1256
1257 self.with_z_index(0, |cx| {
1258 cx.with_key_dispatch(Some(KeyContext::default()), None, |_, cx| {
1259 for (action_type, action_listeners) in &cx.app.global_action_listeners {
1260 for action_listener in action_listeners.iter().cloned() {
1261 cx.window.next_frame.dispatch_tree.on_action(
1262 *action_type,
1263 Rc::new(move |action, phase, cx| action_listener(action, phase, cx)),
1264 )
1265 }
1266 }
1267
1268 let available_space = cx.window.viewport_size.map(Into::into);
1269 root_view.draw(Point::default(), available_space, cx);
1270 })
1271 });
1272
1273 if let Some(active_drag) = self.app.active_drag.take() {
1274 self.with_z_index(ACTIVE_DRAG_Z_INDEX, |cx| {
1275 let offset = cx.mouse_position() - active_drag.cursor_offset;
1276 let available_space = size(AvailableSpace::MinContent, AvailableSpace::MinContent);
1277 active_drag.view.draw(offset, available_space, cx);
1278 });
1279 self.active_drag = Some(active_drag);
1280 } else if let Some(active_tooltip) = self.app.active_tooltip.take() {
1281 self.with_z_index(1, |cx| {
1282 let available_space = size(AvailableSpace::MinContent, AvailableSpace::MinContent);
1283 active_tooltip
1284 .view
1285 .draw(active_tooltip.cursor_offset, available_space, cx);
1286 });
1287 }
1288
1289 let window_is_focused = self
1290 .window
1291 .focus
1292 .and_then(|focus_id| {
1293 self.window
1294 .next_frame
1295 .dispatch_tree
1296 .focusable_node_id(focus_id)
1297 })
1298 .is_some();
1299 if window_was_focused && !window_is_focused {
1300 self.window
1301 .blur_listeners
1302 .clone()
1303 .retain(&(), |listener| listener(self));
1304 }
1305
1306 self.window
1307 .next_frame
1308 .dispatch_tree
1309 .preserve_pending_keystrokes(
1310 &mut self.window.rendered_frame.dispatch_tree,
1311 self.window.focus,
1312 );
1313 self.window.root_view = Some(root_view);
1314
1315 let window = &mut self.window;
1316 mem::swap(&mut window.rendered_frame, &mut window.next_frame);
1317
1318 let scene = self.window.rendered_frame.scene_builder.build();
1319
1320 // Set the cursor only if we're the active window.
1321 let cursor_style = self
1322 .window
1323 .requested_cursor_style
1324 .take()
1325 .unwrap_or(CursorStyle::Arrow);
1326 if self.is_window_active() {
1327 self.platform.set_cursor_style(cursor_style);
1328 }
1329
1330 self.window.dirty = false;
1331
1332 scene
1333 }
1334
1335 /// Dispatch a mouse or keyboard event on the window.
1336 pub fn dispatch_event(&mut self, event: InputEvent) -> bool {
1337 // Handlers may set this to false by calling `stop_propagation`.
1338 self.app.propagate_event = true;
1339 // Handlers may set this to true by calling `prevent_default`.
1340 self.window.default_prevented = false;
1341
1342 let event = match event {
1343 // Track the mouse position with our own state, since accessing the platform
1344 // API for the mouse position can only occur on the main thread.
1345 InputEvent::MouseMove(mouse_move) => {
1346 self.window.mouse_position = mouse_move.position;
1347 self.window.modifiers = mouse_move.modifiers;
1348 InputEvent::MouseMove(mouse_move)
1349 }
1350 InputEvent::MouseDown(mouse_down) => {
1351 self.window.mouse_position = mouse_down.position;
1352 self.window.modifiers = mouse_down.modifiers;
1353 InputEvent::MouseDown(mouse_down)
1354 }
1355 InputEvent::MouseUp(mouse_up) => {
1356 self.window.mouse_position = mouse_up.position;
1357 self.window.modifiers = mouse_up.modifiers;
1358 InputEvent::MouseUp(mouse_up)
1359 }
1360 InputEvent::MouseExited(mouse_exited) => {
1361 // todo!("Should we record that the mouse is outside of the window somehow? Or are these global pixels?")
1362 self.window.modifiers = mouse_exited.modifiers;
1363
1364 InputEvent::MouseExited(mouse_exited)
1365 }
1366 InputEvent::ModifiersChanged(modifiers_changed) => {
1367 self.window.modifiers = modifiers_changed.modifiers;
1368 InputEvent::ModifiersChanged(modifiers_changed)
1369 }
1370 InputEvent::ScrollWheel(scroll_wheel) => {
1371 self.window.mouse_position = scroll_wheel.position;
1372 self.window.modifiers = scroll_wheel.modifiers;
1373 InputEvent::ScrollWheel(scroll_wheel)
1374 }
1375 // Translate dragging and dropping of external files from the operating system
1376 // to internal drag and drop events.
1377 InputEvent::FileDrop(file_drop) => match file_drop {
1378 FileDropEvent::Entered { position, files } => {
1379 self.window.mouse_position = position;
1380 if self.active_drag.is_none() {
1381 self.active_drag = Some(AnyDrag {
1382 value: Box::new(files.clone()),
1383 view: self.build_view(|_| files).into(),
1384 cursor_offset: position,
1385 });
1386 }
1387 InputEvent::MouseMove(MouseMoveEvent {
1388 position,
1389 pressed_button: Some(MouseButton::Left),
1390 modifiers: Modifiers::default(),
1391 })
1392 }
1393 FileDropEvent::Pending { position } => {
1394 self.window.mouse_position = position;
1395 InputEvent::MouseMove(MouseMoveEvent {
1396 position,
1397 pressed_button: Some(MouseButton::Left),
1398 modifiers: Modifiers::default(),
1399 })
1400 }
1401 FileDropEvent::Submit { position } => {
1402 self.activate(true);
1403 self.window.mouse_position = position;
1404 InputEvent::MouseUp(MouseUpEvent {
1405 button: MouseButton::Left,
1406 position,
1407 modifiers: Modifiers::default(),
1408 click_count: 1,
1409 })
1410 }
1411 FileDropEvent::Exited => InputEvent::MouseUp(MouseUpEvent {
1412 button: MouseButton::Left,
1413 position: Point::default(),
1414 modifiers: Modifiers::default(),
1415 click_count: 1,
1416 }),
1417 },
1418 InputEvent::KeyDown(_) | InputEvent::KeyUp(_) => event,
1419 };
1420
1421 if let Some(any_mouse_event) = event.mouse_event() {
1422 self.dispatch_mouse_event(any_mouse_event);
1423 } else if let Some(any_key_event) = event.keyboard_event() {
1424 self.dispatch_key_event(any_key_event);
1425 }
1426
1427 !self.app.propagate_event
1428 }
1429
1430 fn dispatch_mouse_event(&mut self, event: &dyn Any) {
1431 if let Some(mut handlers) = self
1432 .window
1433 .rendered_frame
1434 .mouse_listeners
1435 .remove(&event.type_id())
1436 {
1437 // Because handlers may add other handlers, we sort every time.
1438 handlers.sort_by(|(a, _), (b, _)| a.cmp(b));
1439
1440 // Capture phase, events bubble from back to front. Handlers for this phase are used for
1441 // special purposes, such as detecting events outside of a given Bounds.
1442 for (_, handler) in &mut handlers {
1443 handler(event, DispatchPhase::Capture, self);
1444 if !self.app.propagate_event {
1445 break;
1446 }
1447 }
1448
1449 // Bubble phase, where most normal handlers do their work.
1450 if self.app.propagate_event {
1451 for (_, handler) in handlers.iter_mut().rev() {
1452 handler(event, DispatchPhase::Bubble, self);
1453 if !self.app.propagate_event {
1454 break;
1455 }
1456 }
1457 }
1458
1459 if self.app.propagate_event && event.downcast_ref::<MouseUpEvent>().is_some() {
1460 self.active_drag = None;
1461 }
1462
1463 self.window
1464 .rendered_frame
1465 .mouse_listeners
1466 .insert(event.type_id(), handlers);
1467 }
1468 }
1469
1470 fn dispatch_key_event(&mut self, event: &dyn Any) {
1471 let node_id = self
1472 .window
1473 .focus
1474 .and_then(|focus_id| {
1475 self.window
1476 .rendered_frame
1477 .dispatch_tree
1478 .focusable_node_id(focus_id)
1479 })
1480 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
1481
1482 let dispatch_path = self
1483 .window
1484 .rendered_frame
1485 .dispatch_tree
1486 .dispatch_path(node_id);
1487
1488 let mut actions: Vec<Box<dyn Action>> = Vec::new();
1489
1490 // Capture phase
1491 let mut context_stack: SmallVec<[KeyContext; 16]> = SmallVec::new();
1492 self.propagate_event = true;
1493
1494 for node_id in &dispatch_path {
1495 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1496
1497 if let Some(context) = node.context.clone() {
1498 context_stack.push(context);
1499 }
1500
1501 for key_listener in node.key_listeners.clone() {
1502 key_listener(event, DispatchPhase::Capture, self);
1503 if !self.propagate_event {
1504 return;
1505 }
1506 }
1507 }
1508
1509 // Bubble phase
1510 for node_id in dispatch_path.iter().rev() {
1511 // Handle low level key events
1512 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1513 for key_listener in node.key_listeners.clone() {
1514 key_listener(event, DispatchPhase::Bubble, self);
1515 if !self.propagate_event {
1516 return;
1517 }
1518 }
1519
1520 // Match keystrokes
1521 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1522 if node.context.is_some() {
1523 if let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() {
1524 let mut new_actions = self
1525 .window
1526 .rendered_frame
1527 .dispatch_tree
1528 .dispatch_key(&key_down_event.keystroke, &context_stack);
1529 actions.append(&mut new_actions);
1530 }
1531
1532 context_stack.pop();
1533 }
1534 }
1535
1536 for action in actions {
1537 self.dispatch_action_on_node(node_id, action.boxed_clone());
1538 if !self.propagate_event {
1539 self.dispatch_keystroke_observers(event, Some(action));
1540 return;
1541 }
1542 }
1543 self.dispatch_keystroke_observers(event, None);
1544 }
1545
1546 pub fn has_pending_keystrokes(&self) -> bool {
1547 self.window
1548 .rendered_frame
1549 .dispatch_tree
1550 .has_pending_keystrokes()
1551 }
1552
1553 fn dispatch_action_on_node(&mut self, node_id: DispatchNodeId, action: Box<dyn Action>) {
1554 let dispatch_path = self
1555 .window
1556 .rendered_frame
1557 .dispatch_tree
1558 .dispatch_path(node_id);
1559
1560 // Capture phase
1561 for node_id in &dispatch_path {
1562 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1563 for DispatchActionListener {
1564 action_type,
1565 listener,
1566 } in node.action_listeners.clone()
1567 {
1568 let any_action = action.as_any();
1569 if action_type == any_action.type_id() {
1570 listener(any_action, DispatchPhase::Capture, self);
1571 if !self.propagate_event {
1572 return;
1573 }
1574 }
1575 }
1576 }
1577 // Bubble phase
1578 for node_id in dispatch_path.iter().rev() {
1579 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1580 for DispatchActionListener {
1581 action_type,
1582 listener,
1583 } in node.action_listeners.clone()
1584 {
1585 let any_action = action.as_any();
1586 if action_type == any_action.type_id() {
1587 self.propagate_event = false; // Actions stop propagation by default during the bubble phase
1588 listener(any_action, DispatchPhase::Bubble, self);
1589 if !self.propagate_event {
1590 return;
1591 }
1592 }
1593 }
1594 }
1595 }
1596
1597 /// Register the given handler to be invoked whenever the global of the given type
1598 /// is updated.
1599 pub fn observe_global<G: 'static>(
1600 &mut self,
1601 f: impl Fn(&mut WindowContext<'_>) + 'static,
1602 ) -> Subscription {
1603 let window_handle = self.window.handle;
1604 let (subscription, activate) = self.global_observers.insert(
1605 TypeId::of::<G>(),
1606 Box::new(move |cx| window_handle.update(cx, |_, cx| f(cx)).is_ok()),
1607 );
1608 self.app.defer(move |_| activate());
1609 subscription
1610 }
1611
1612 pub fn activate_window(&self) {
1613 self.window.platform_window.activate();
1614 }
1615
1616 pub fn minimize_window(&self) {
1617 self.window.platform_window.minimize();
1618 }
1619
1620 pub fn toggle_full_screen(&self) {
1621 self.window.platform_window.toggle_full_screen();
1622 }
1623
1624 pub fn prompt(
1625 &self,
1626 level: PromptLevel,
1627 msg: &str,
1628 answers: &[&str],
1629 ) -> oneshot::Receiver<usize> {
1630 self.window.platform_window.prompt(level, msg, answers)
1631 }
1632
1633 pub fn available_actions(&self) -> Vec<Box<dyn Action>> {
1634 let node_id = self
1635 .window
1636 .focus
1637 .and_then(|focus_id| {
1638 self.window
1639 .rendered_frame
1640 .dispatch_tree
1641 .focusable_node_id(focus_id)
1642 })
1643 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
1644
1645 self.window
1646 .rendered_frame
1647 .dispatch_tree
1648 .available_actions(node_id)
1649 }
1650
1651 pub fn bindings_for_action(&self, action: &dyn Action) -> Vec<KeyBinding> {
1652 self.window
1653 .rendered_frame
1654 .dispatch_tree
1655 .bindings_for_action(
1656 action,
1657 &self.window.rendered_frame.dispatch_tree.context_stack,
1658 )
1659 }
1660
1661 pub fn bindings_for_action_in(
1662 &self,
1663 action: &dyn Action,
1664 focus_handle: &FocusHandle,
1665 ) -> Vec<KeyBinding> {
1666 let dispatch_tree = &self.window.rendered_frame.dispatch_tree;
1667
1668 let Some(node_id) = dispatch_tree.focusable_node_id(focus_handle.id) else {
1669 return vec![];
1670 };
1671 let context_stack = dispatch_tree
1672 .dispatch_path(node_id)
1673 .into_iter()
1674 .filter_map(|node_id| dispatch_tree.node(node_id).context.clone())
1675 .collect();
1676 dispatch_tree.bindings_for_action(action, &context_stack)
1677 }
1678
1679 pub fn listener_for<V: Render, E>(
1680 &self,
1681 view: &View<V>,
1682 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
1683 ) -> impl Fn(&E, &mut WindowContext) + 'static {
1684 let view = view.downgrade();
1685 move |e: &E, cx: &mut WindowContext| {
1686 view.update(cx, |view, cx| f(view, e, cx)).ok();
1687 }
1688 }
1689
1690 pub fn handler_for<V: Render>(
1691 &self,
1692 view: &View<V>,
1693 f: impl Fn(&mut V, &mut ViewContext<V>) + 'static,
1694 ) -> impl Fn(&mut WindowContext) {
1695 let view = view.downgrade();
1696 move |cx: &mut WindowContext| {
1697 view.update(cx, |view, cx| f(view, cx)).ok();
1698 }
1699 }
1700
1701 //========== ELEMENT RELATED FUNCTIONS ===========
1702 pub fn with_key_dispatch<R>(
1703 &mut self,
1704 context: Option<KeyContext>,
1705 focus_handle: Option<FocusHandle>,
1706 f: impl FnOnce(Option<FocusHandle>, &mut Self) -> R,
1707 ) -> R {
1708 let window = &mut self.window;
1709 window.next_frame.dispatch_tree.push_node(context.clone());
1710 if let Some(focus_handle) = focus_handle.as_ref() {
1711 window
1712 .next_frame
1713 .dispatch_tree
1714 .make_focusable(focus_handle.id);
1715 }
1716 let result = f(focus_handle, self);
1717
1718 self.window.next_frame.dispatch_tree.pop_node();
1719
1720 result
1721 }
1722
1723 /// Register a focus listener for the next frame only. It will be cleared
1724 /// on the next frame render. You should use this method only from within elements,
1725 /// and we may want to enforce that better via a different context type.
1726 // todo!() Move this to `FrameContext` to emphasize its individuality?
1727 pub fn on_focus_changed(
1728 &mut self,
1729 listener: impl Fn(&FocusEvent, &mut WindowContext) + 'static,
1730 ) {
1731 self.window
1732 .next_frame
1733 .focus_listeners
1734 .push(Box::new(move |event, cx| {
1735 listener(event, cx);
1736 }));
1737 }
1738
1739 /// Set an input handler, such as [ElementInputHandler], which interfaces with the
1740 /// platform to receive textual input with proper integration with concerns such
1741 /// as IME interactions.
1742 pub fn handle_input(
1743 &mut self,
1744 focus_handle: &FocusHandle,
1745 input_handler: impl PlatformInputHandler,
1746 ) {
1747 if focus_handle.is_focused(self) {
1748 self.window
1749 .platform_window
1750 .set_input_handler(Box::new(input_handler));
1751 }
1752 }
1753
1754 pub fn on_window_should_close(&mut self, f: impl Fn(&mut WindowContext) -> bool + 'static) {
1755 let mut this = self.to_async();
1756 self.window
1757 .platform_window
1758 .on_should_close(Box::new(move || this.update(|_, cx| f(cx)).unwrap_or(true)))
1759 }
1760}
1761
1762impl Context for WindowContext<'_> {
1763 type Result<T> = T;
1764
1765 fn build_model<T>(
1766 &mut self,
1767 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
1768 ) -> Model<T>
1769 where
1770 T: 'static,
1771 {
1772 let slot = self.app.entities.reserve();
1773 let model = build_model(&mut ModelContext::new(&mut *self.app, slot.downgrade()));
1774 self.entities.insert(slot, model)
1775 }
1776
1777 fn update_model<T: 'static, R>(
1778 &mut self,
1779 model: &Model<T>,
1780 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
1781 ) -> R {
1782 let mut entity = self.entities.lease(model);
1783 let result = update(
1784 &mut *entity,
1785 &mut ModelContext::new(&mut *self.app, model.downgrade()),
1786 );
1787 self.entities.end_lease(entity);
1788 result
1789 }
1790
1791 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
1792 where
1793 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
1794 {
1795 if window == self.window.handle {
1796 let root_view = self.window.root_view.clone().unwrap();
1797 Ok(update(root_view, self))
1798 } else {
1799 window.update(self.app, update)
1800 }
1801 }
1802
1803 fn read_model<T, R>(
1804 &self,
1805 handle: &Model<T>,
1806 read: impl FnOnce(&T, &AppContext) -> R,
1807 ) -> Self::Result<R>
1808 where
1809 T: 'static,
1810 {
1811 let entity = self.entities.read(handle);
1812 read(&*entity, &*self.app)
1813 }
1814
1815 fn read_window<T, R>(
1816 &self,
1817 window: &WindowHandle<T>,
1818 read: impl FnOnce(View<T>, &AppContext) -> R,
1819 ) -> Result<R>
1820 where
1821 T: 'static,
1822 {
1823 if window.any_handle == self.window.handle {
1824 let root_view = self
1825 .window
1826 .root_view
1827 .clone()
1828 .unwrap()
1829 .downcast::<T>()
1830 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
1831 Ok(read(root_view, self))
1832 } else {
1833 self.app.read_window(window, read)
1834 }
1835 }
1836}
1837
1838impl VisualContext for WindowContext<'_> {
1839 fn build_view<V>(
1840 &mut self,
1841 build_view_state: impl FnOnce(&mut ViewContext<'_, V>) -> V,
1842 ) -> Self::Result<View<V>>
1843 where
1844 V: 'static + Render,
1845 {
1846 let slot = self.app.entities.reserve();
1847 let view = View {
1848 model: slot.clone(),
1849 };
1850 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
1851 let entity = build_view_state(&mut cx);
1852 cx.entities.insert(slot, entity);
1853
1854 cx.new_view_observers
1855 .clone()
1856 .retain(&TypeId::of::<V>(), |observer| {
1857 let any_view = AnyView::from(view.clone());
1858 (observer)(any_view, self);
1859 true
1860 });
1861
1862 view
1863 }
1864
1865 /// Update the given view. Prefer calling `View::update` instead, which calls this method.
1866 fn update_view<T: 'static, R>(
1867 &mut self,
1868 view: &View<T>,
1869 update: impl FnOnce(&mut T, &mut ViewContext<'_, T>) -> R,
1870 ) -> Self::Result<R> {
1871 let mut lease = self.app.entities.lease(&view.model);
1872 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
1873 let result = update(&mut *lease, &mut cx);
1874 cx.app.entities.end_lease(lease);
1875 result
1876 }
1877
1878 fn replace_root_view<V>(
1879 &mut self,
1880 build_view: impl FnOnce(&mut ViewContext<'_, V>) -> V,
1881 ) -> Self::Result<View<V>>
1882 where
1883 V: 'static + Render,
1884 {
1885 let slot = self.app.entities.reserve();
1886 let view = View {
1887 model: slot.clone(),
1888 };
1889 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
1890 let entity = build_view(&mut cx);
1891 self.entities.insert(slot, entity);
1892 self.window.root_view = Some(view.clone().into());
1893 view
1894 }
1895
1896 fn focus_view<V: crate::FocusableView>(&mut self, view: &View<V>) -> Self::Result<()> {
1897 self.update_view(view, |view, cx| {
1898 view.focus_handle(cx).clone().focus(cx);
1899 })
1900 }
1901
1902 fn dismiss_view<V>(&mut self, view: &View<V>) -> Self::Result<()>
1903 where
1904 V: ManagedView,
1905 {
1906 self.update_view(view, |_, cx| cx.emit(DismissEvent))
1907 }
1908}
1909
1910impl<'a> std::ops::Deref for WindowContext<'a> {
1911 type Target = AppContext;
1912
1913 fn deref(&self) -> &Self::Target {
1914 &self.app
1915 }
1916}
1917
1918impl<'a> std::ops::DerefMut for WindowContext<'a> {
1919 fn deref_mut(&mut self) -> &mut Self::Target {
1920 &mut self.app
1921 }
1922}
1923
1924impl<'a> Borrow<AppContext> for WindowContext<'a> {
1925 fn borrow(&self) -> &AppContext {
1926 &self.app
1927 }
1928}
1929
1930impl<'a> BorrowMut<AppContext> for WindowContext<'a> {
1931 fn borrow_mut(&mut self) -> &mut AppContext {
1932 &mut self.app
1933 }
1934}
1935
1936pub trait BorrowWindow: BorrowMut<Window> + BorrowMut<AppContext> {
1937 fn app_mut(&mut self) -> &mut AppContext {
1938 self.borrow_mut()
1939 }
1940
1941 fn app(&self) -> &AppContext {
1942 self.borrow()
1943 }
1944
1945 fn window(&self) -> &Window {
1946 self.borrow()
1947 }
1948
1949 fn window_mut(&mut self) -> &mut Window {
1950 self.borrow_mut()
1951 }
1952
1953 /// Pushes the given element id onto the global stack and invokes the given closure
1954 /// with a `GlobalElementId`, which disambiguates the given id in the context of its ancestor
1955 /// ids. Because elements are discarded and recreated on each frame, the `GlobalElementId` is
1956 /// used to associate state with identified elements across separate frames.
1957 fn with_element_id<R>(
1958 &mut self,
1959 id: Option<impl Into<ElementId>>,
1960 f: impl FnOnce(&mut Self) -> R,
1961 ) -> R {
1962 if let Some(id) = id.map(Into::into) {
1963 let window = self.window_mut();
1964 window.element_id_stack.push(id.into());
1965 let result = f(self);
1966 let window: &mut Window = self.borrow_mut();
1967 window.element_id_stack.pop();
1968 result
1969 } else {
1970 f(self)
1971 }
1972 }
1973
1974 /// Invoke the given function with the given content mask after intersecting it
1975 /// with the current mask.
1976 fn with_content_mask<R>(
1977 &mut self,
1978 mask: Option<ContentMask<Pixels>>,
1979 f: impl FnOnce(&mut Self) -> R,
1980 ) -> R {
1981 if let Some(mask) = mask {
1982 let mask = mask.intersect(&self.content_mask());
1983 self.window_mut().next_frame.content_mask_stack.push(mask);
1984 let result = f(self);
1985 self.window_mut().next_frame.content_mask_stack.pop();
1986 result
1987 } else {
1988 f(self)
1989 }
1990 }
1991
1992 /// Invoke the given function with the content mask reset to that
1993 /// of the window.
1994 fn break_content_mask<R>(&mut self, f: impl FnOnce(&mut Self) -> R) -> R {
1995 let mask = ContentMask {
1996 bounds: Bounds {
1997 origin: Point::default(),
1998 size: self.window().viewport_size,
1999 },
2000 };
2001 self.window_mut().next_frame.content_mask_stack.push(mask);
2002 let result = f(self);
2003 self.window_mut().next_frame.content_mask_stack.pop();
2004 result
2005 }
2006
2007 /// Update the global element offset relative to the current offset. This is used to implement
2008 /// scrolling.
2009 fn with_element_offset<R>(
2010 &mut self,
2011 offset: Point<Pixels>,
2012 f: impl FnOnce(&mut Self) -> R,
2013 ) -> R {
2014 if offset.is_zero() {
2015 return f(self);
2016 };
2017
2018 let abs_offset = self.element_offset() + offset;
2019 self.with_absolute_element_offset(abs_offset, f)
2020 }
2021
2022 /// Update the global element offset based on the given offset. This is used to implement
2023 /// drag handles and other manual painting of elements.
2024 fn with_absolute_element_offset<R>(
2025 &mut self,
2026 offset: Point<Pixels>,
2027 f: impl FnOnce(&mut Self) -> R,
2028 ) -> R {
2029 self.window_mut()
2030 .next_frame
2031 .element_offset_stack
2032 .push(offset);
2033 let result = f(self);
2034 self.window_mut().next_frame.element_offset_stack.pop();
2035 result
2036 }
2037
2038 /// Obtain the current element offset.
2039 fn element_offset(&self) -> Point<Pixels> {
2040 self.window()
2041 .next_frame
2042 .element_offset_stack
2043 .last()
2044 .copied()
2045 .unwrap_or_default()
2046 }
2047
2048 /// Update or initialize state for an element with the given id that lives across multiple
2049 /// frames. If an element with this id existed in the rendered frame, its state will be passed
2050 /// to the given closure. The state returned by the closure will be stored so it can be referenced
2051 /// when drawing the next frame.
2052 fn with_element_state<S, R>(
2053 &mut self,
2054 id: ElementId,
2055 f: impl FnOnce(Option<S>, &mut Self) -> (R, S),
2056 ) -> R
2057 where
2058 S: 'static,
2059 {
2060 self.with_element_id(Some(id), |cx| {
2061 let global_id = cx.window().element_id_stack.clone();
2062
2063 if let Some(any) = cx
2064 .window_mut()
2065 .next_frame
2066 .element_states
2067 .remove(&global_id)
2068 .or_else(|| {
2069 cx.window_mut()
2070 .rendered_frame
2071 .element_states
2072 .remove(&global_id)
2073 })
2074 {
2075 let ElementStateBox {
2076 inner,
2077
2078 #[cfg(debug_assertions)]
2079 type_name
2080 } = any;
2081 // Using the extra inner option to avoid needing to reallocate a new box.
2082 let mut state_box = inner
2083 .downcast::<Option<S>>()
2084 .map_err(|_| {
2085 #[cfg(debug_assertions)]
2086 {
2087 anyhow!(
2088 "invalid element state type for id, requested_type {:?}, actual type: {:?}",
2089 std::any::type_name::<S>(),
2090 type_name
2091 )
2092 }
2093
2094 #[cfg(not(debug_assertions))]
2095 {
2096 anyhow!(
2097 "invalid element state type for id, requested_type {:?}",
2098 std::any::type_name::<S>(),
2099 )
2100 }
2101 })
2102 .unwrap();
2103
2104 // Actual: Option<AnyElement> <- View
2105 // Requested: () <- AnyElemet
2106 let state = state_box
2107 .take()
2108 .expect("element state is already on the stack");
2109 let (result, state) = f(Some(state), cx);
2110 state_box.replace(state);
2111 cx.window_mut()
2112 .next_frame
2113 .element_states
2114 .insert(global_id, ElementStateBox {
2115 inner: state_box,
2116
2117 #[cfg(debug_assertions)]
2118 type_name
2119 });
2120 result
2121 } else {
2122 let (result, state) = f(None, cx);
2123 cx.window_mut()
2124 .next_frame
2125 .element_states
2126 .insert(global_id,
2127 ElementStateBox {
2128 inner: Box::new(Some(state)),
2129
2130 #[cfg(debug_assertions)]
2131 type_name: std::any::type_name::<S>()
2132 }
2133
2134 );
2135 result
2136 }
2137 })
2138 }
2139
2140 /// Obtain the current content mask.
2141 fn content_mask(&self) -> ContentMask<Pixels> {
2142 self.window()
2143 .next_frame
2144 .content_mask_stack
2145 .last()
2146 .cloned()
2147 .unwrap_or_else(|| ContentMask {
2148 bounds: Bounds {
2149 origin: Point::default(),
2150 size: self.window().viewport_size,
2151 },
2152 })
2153 }
2154
2155 /// The size of an em for the base font of the application. Adjusting this value allows the
2156 /// UI to scale, just like zooming a web page.
2157 fn rem_size(&self) -> Pixels {
2158 self.window().rem_size
2159 }
2160}
2161
2162impl Borrow<Window> for WindowContext<'_> {
2163 fn borrow(&self) -> &Window {
2164 &self.window
2165 }
2166}
2167
2168impl BorrowMut<Window> for WindowContext<'_> {
2169 fn borrow_mut(&mut self) -> &mut Window {
2170 &mut self.window
2171 }
2172}
2173
2174impl<T> BorrowWindow for T where T: BorrowMut<AppContext> + BorrowMut<Window> {}
2175
2176pub struct ViewContext<'a, V> {
2177 window_cx: WindowContext<'a>,
2178 view: &'a View<V>,
2179}
2180
2181impl<V> Borrow<AppContext> for ViewContext<'_, V> {
2182 fn borrow(&self) -> &AppContext {
2183 &*self.window_cx.app
2184 }
2185}
2186
2187impl<V> BorrowMut<AppContext> for ViewContext<'_, V> {
2188 fn borrow_mut(&mut self) -> &mut AppContext {
2189 &mut *self.window_cx.app
2190 }
2191}
2192
2193impl<V> Borrow<Window> for ViewContext<'_, V> {
2194 fn borrow(&self) -> &Window {
2195 &*self.window_cx.window
2196 }
2197}
2198
2199impl<V> BorrowMut<Window> for ViewContext<'_, V> {
2200 fn borrow_mut(&mut self) -> &mut Window {
2201 &mut *self.window_cx.window
2202 }
2203}
2204
2205impl<'a, V: 'static> ViewContext<'a, V> {
2206 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window, view: &'a View<V>) -> Self {
2207 Self {
2208 window_cx: WindowContext::new(app, window),
2209 view,
2210 }
2211 }
2212
2213 pub fn entity_id(&self) -> EntityId {
2214 self.view.entity_id()
2215 }
2216
2217 pub fn view(&self) -> &View<V> {
2218 self.view
2219 }
2220
2221 pub fn model(&self) -> &Model<V> {
2222 &self.view.model
2223 }
2224
2225 /// Access the underlying window context.
2226 pub fn window_context(&mut self) -> &mut WindowContext<'a> {
2227 &mut self.window_cx
2228 }
2229
2230 pub fn with_z_index<R>(&mut self, z_index: u32, f: impl FnOnce(&mut Self) -> R) -> R {
2231 self.window.next_frame.z_index_stack.push(z_index);
2232 let result = f(self);
2233 self.window.next_frame.z_index_stack.pop();
2234 result
2235 }
2236
2237 pub fn on_next_frame(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static)
2238 where
2239 V: 'static,
2240 {
2241 let view = self.view().clone();
2242 self.window_cx.on_next_frame(move |cx| view.update(cx, f));
2243 }
2244
2245 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
2246 /// that are currently on the stack to be returned to the app.
2247 pub fn defer(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static) {
2248 let view = self.view().downgrade();
2249 self.window_cx.defer(move |cx| {
2250 view.update(cx, f).ok();
2251 });
2252 }
2253
2254 pub fn observe<V2, E>(
2255 &mut self,
2256 entity: &E,
2257 mut on_notify: impl FnMut(&mut V, E, &mut ViewContext<'_, V>) + 'static,
2258 ) -> Subscription
2259 where
2260 V2: 'static,
2261 V: 'static,
2262 E: Entity<V2>,
2263 {
2264 let view = self.view().downgrade();
2265 let entity_id = entity.entity_id();
2266 let entity = entity.downgrade();
2267 let window_handle = self.window.handle;
2268 let (subscription, activate) = self.app.observers.insert(
2269 entity_id,
2270 Box::new(move |cx| {
2271 window_handle
2272 .update(cx, |_, cx| {
2273 if let Some(handle) = E::upgrade_from(&entity) {
2274 view.update(cx, |this, cx| on_notify(this, handle, cx))
2275 .is_ok()
2276 } else {
2277 false
2278 }
2279 })
2280 .unwrap_or(false)
2281 }),
2282 );
2283 self.app.defer(move |_| activate());
2284 subscription
2285 }
2286
2287 pub fn subscribe<V2, E, Evt>(
2288 &mut self,
2289 entity: &E,
2290 mut on_event: impl FnMut(&mut V, E, &Evt, &mut ViewContext<'_, V>) + 'static,
2291 ) -> Subscription
2292 where
2293 V2: EventEmitter<Evt>,
2294 E: Entity<V2>,
2295 Evt: 'static,
2296 {
2297 let view = self.view().downgrade();
2298 let entity_id = entity.entity_id();
2299 let handle = entity.downgrade();
2300 let window_handle = self.window.handle;
2301 let (subscription, activate) = self.app.event_listeners.insert(
2302 entity_id,
2303 (
2304 TypeId::of::<Evt>(),
2305 Box::new(move |event, cx| {
2306 window_handle
2307 .update(cx, |_, cx| {
2308 if let Some(handle) = E::upgrade_from(&handle) {
2309 let event = event.downcast_ref().expect("invalid event type");
2310 view.update(cx, |this, cx| on_event(this, handle, event, cx))
2311 .is_ok()
2312 } else {
2313 false
2314 }
2315 })
2316 .unwrap_or(false)
2317 }),
2318 ),
2319 );
2320 self.app.defer(move |_| activate());
2321 subscription
2322 }
2323
2324 pub fn on_release(
2325 &mut self,
2326 on_release: impl FnOnce(&mut V, &mut WindowContext) + 'static,
2327 ) -> Subscription {
2328 let window_handle = self.window.handle;
2329 let (subscription, activate) = self.app.release_listeners.insert(
2330 self.view.model.entity_id,
2331 Box::new(move |this, cx| {
2332 let this = this.downcast_mut().expect("invalid entity type");
2333 let _ = window_handle.update(cx, |_, cx| on_release(this, cx));
2334 }),
2335 );
2336 activate();
2337 subscription
2338 }
2339
2340 pub fn observe_release<V2, E>(
2341 &mut self,
2342 entity: &E,
2343 mut on_release: impl FnMut(&mut V, &mut V2, &mut ViewContext<'_, V>) + 'static,
2344 ) -> Subscription
2345 where
2346 V: 'static,
2347 V2: 'static,
2348 E: Entity<V2>,
2349 {
2350 let view = self.view().downgrade();
2351 let entity_id = entity.entity_id();
2352 let window_handle = self.window.handle;
2353 let (subscription, activate) = self.app.release_listeners.insert(
2354 entity_id,
2355 Box::new(move |entity, cx| {
2356 let entity = entity.downcast_mut().expect("invalid entity type");
2357 let _ = window_handle.update(cx, |_, cx| {
2358 view.update(cx, |this, cx| on_release(this, entity, cx))
2359 });
2360 }),
2361 );
2362 activate();
2363 subscription
2364 }
2365
2366 pub fn notify(&mut self) {
2367 self.window_cx.notify();
2368 self.window_cx.app.push_effect(Effect::Notify {
2369 emitter: self.view.model.entity_id,
2370 });
2371 }
2372
2373 pub fn observe_window_bounds(
2374 &mut self,
2375 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2376 ) -> Subscription {
2377 let view = self.view.downgrade();
2378 let (subscription, activate) = self.window.bounds_observers.insert(
2379 (),
2380 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
2381 );
2382 activate();
2383 subscription
2384 }
2385
2386 pub fn observe_window_activation(
2387 &mut self,
2388 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2389 ) -> Subscription {
2390 let view = self.view.downgrade();
2391 let (subscription, activate) = self.window.activation_observers.insert(
2392 (),
2393 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
2394 );
2395 activate();
2396 subscription
2397 }
2398
2399 /// Register a listener to be called when the given focus handle receives focus.
2400 /// Unlike [on_focus_changed], returns a subscription and persists until the subscription
2401 /// is dropped.
2402 pub fn on_focus(
2403 &mut self,
2404 handle: &FocusHandle,
2405 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2406 ) -> Subscription {
2407 let view = self.view.downgrade();
2408 let focus_id = handle.id;
2409 let (subscription, activate) = self.window.focus_listeners.insert(
2410 (),
2411 Box::new(move |event, cx| {
2412 view.update(cx, |view, cx| {
2413 if event.focused.as_ref().map(|focused| focused.id) == Some(focus_id) {
2414 listener(view, cx)
2415 }
2416 })
2417 .is_ok()
2418 }),
2419 );
2420 self.app.defer(move |_| activate());
2421 subscription
2422 }
2423
2424 /// Register a listener to be called when the given focus handle or one of its descendants receives focus.
2425 /// Unlike [on_focus_changed], returns a subscription and persists until the subscription
2426 /// is dropped.
2427 pub fn on_focus_in(
2428 &mut self,
2429 handle: &FocusHandle,
2430 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2431 ) -> Subscription {
2432 let view = self.view.downgrade();
2433 let focus_id = handle.id;
2434 let (subscription, activate) = self.window.focus_listeners.insert(
2435 (),
2436 Box::new(move |event, cx| {
2437 view.update(cx, |view, cx| {
2438 if event
2439 .focused
2440 .as_ref()
2441 .map_or(false, |focused| focus_id.contains(focused.id, cx))
2442 {
2443 listener(view, cx)
2444 }
2445 })
2446 .is_ok()
2447 }),
2448 );
2449 self.app.defer(move |_| activate());
2450 subscription
2451 }
2452
2453 /// Register a listener to be called when the given focus handle loses focus.
2454 /// Unlike [on_focus_changed], returns a subscription and persists until the subscription
2455 /// is dropped.
2456 pub fn on_blur(
2457 &mut self,
2458 handle: &FocusHandle,
2459 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2460 ) -> Subscription {
2461 let view = self.view.downgrade();
2462 let focus_id = handle.id;
2463 let (subscription, activate) = self.window.focus_listeners.insert(
2464 (),
2465 Box::new(move |event, cx| {
2466 view.update(cx, |view, cx| {
2467 if event.blurred.as_ref().map(|blurred| blurred.id) == Some(focus_id) {
2468 listener(view, cx)
2469 }
2470 })
2471 .is_ok()
2472 }),
2473 );
2474 self.app.defer(move |_| activate());
2475 subscription
2476 }
2477
2478 /// Register a listener to be called when the window loses focus.
2479 /// Unlike [on_focus_changed], returns a subscription and persists until the subscription
2480 /// is dropped.
2481 pub fn on_blur_window(
2482 &mut self,
2483 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2484 ) -> Subscription {
2485 let view = self.view.downgrade();
2486 let (subscription, activate) = self.window.blur_listeners.insert(
2487 (),
2488 Box::new(move |cx| view.update(cx, |view, cx| listener(view, cx)).is_ok()),
2489 );
2490 activate();
2491 subscription
2492 }
2493
2494 /// Register a listener to be called when the given focus handle or one of its descendants loses focus.
2495 /// Unlike [on_focus_changed], returns a subscription and persists until the subscription
2496 /// is dropped.
2497 pub fn on_focus_out(
2498 &mut self,
2499 handle: &FocusHandle,
2500 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2501 ) -> Subscription {
2502 let view = self.view.downgrade();
2503 let focus_id = handle.id;
2504 let (subscription, activate) = self.window.focus_listeners.insert(
2505 (),
2506 Box::new(move |event, cx| {
2507 view.update(cx, |view, cx| {
2508 if event
2509 .blurred
2510 .as_ref()
2511 .map_or(false, |blurred| focus_id.contains(blurred.id, cx))
2512 {
2513 listener(view, cx)
2514 }
2515 })
2516 .is_ok()
2517 }),
2518 );
2519 self.app.defer(move |_| activate());
2520 subscription
2521 }
2522
2523 pub fn spawn<Fut, R>(
2524 &mut self,
2525 f: impl FnOnce(WeakView<V>, AsyncWindowContext) -> Fut,
2526 ) -> Task<R>
2527 where
2528 R: 'static,
2529 Fut: Future<Output = R> + 'static,
2530 {
2531 let view = self.view().downgrade();
2532 self.window_cx.spawn(|cx| f(view, cx))
2533 }
2534
2535 pub fn update_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
2536 where
2537 G: 'static,
2538 {
2539 let mut global = self.app.lease_global::<G>();
2540 let result = f(&mut global, self);
2541 self.app.end_global_lease(global);
2542 result
2543 }
2544
2545 pub fn observe_global<G: 'static>(
2546 &mut self,
2547 mut f: impl FnMut(&mut V, &mut ViewContext<'_, V>) + 'static,
2548 ) -> Subscription {
2549 let window_handle = self.window.handle;
2550 let view = self.view().downgrade();
2551 let (subscription, activate) = self.global_observers.insert(
2552 TypeId::of::<G>(),
2553 Box::new(move |cx| {
2554 window_handle
2555 .update(cx, |_, cx| view.update(cx, |view, cx| f(view, cx)).is_ok())
2556 .unwrap_or(false)
2557 }),
2558 );
2559 self.app.defer(move |_| activate());
2560 subscription
2561 }
2562
2563 pub fn on_mouse_event<Event: 'static>(
2564 &mut self,
2565 handler: impl Fn(&mut V, &Event, DispatchPhase, &mut ViewContext<V>) + 'static,
2566 ) {
2567 let handle = self.view().clone();
2568 self.window_cx.on_mouse_event(move |event, phase, cx| {
2569 handle.update(cx, |view, cx| {
2570 handler(view, event, phase, cx);
2571 })
2572 });
2573 }
2574
2575 pub fn on_key_event<Event: 'static>(
2576 &mut self,
2577 handler: impl Fn(&mut V, &Event, DispatchPhase, &mut ViewContext<V>) + 'static,
2578 ) {
2579 let handle = self.view().clone();
2580 self.window_cx.on_key_event(move |event, phase, cx| {
2581 handle.update(cx, |view, cx| {
2582 handler(view, event, phase, cx);
2583 })
2584 });
2585 }
2586
2587 pub fn on_action(
2588 &mut self,
2589 action_type: TypeId,
2590 handler: impl Fn(&mut V, &dyn Any, DispatchPhase, &mut ViewContext<V>) + 'static,
2591 ) {
2592 let handle = self.view().clone();
2593 self.window_cx
2594 .on_action(action_type, move |action, phase, cx| {
2595 handle.update(cx, |view, cx| {
2596 handler(view, action, phase, cx);
2597 })
2598 });
2599 }
2600
2601 pub fn emit<Evt>(&mut self, event: Evt)
2602 where
2603 Evt: 'static,
2604 V: EventEmitter<Evt>,
2605 {
2606 let emitter = self.view.model.entity_id;
2607 self.app.push_effect(Effect::Emit {
2608 emitter,
2609 event_type: TypeId::of::<Evt>(),
2610 event: Box::new(event),
2611 });
2612 }
2613
2614 pub fn focus_self(&mut self)
2615 where
2616 V: FocusableView,
2617 {
2618 self.defer(|view, cx| view.focus_handle(cx).focus(cx))
2619 }
2620
2621 pub fn dismiss_self(&mut self)
2622 where
2623 V: ManagedView,
2624 {
2625 self.defer(|_, cx| cx.emit(DismissEvent))
2626 }
2627
2628 pub fn listener<E>(
2629 &self,
2630 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
2631 ) -> impl Fn(&E, &mut WindowContext) + 'static {
2632 let view = self.view().downgrade();
2633 move |e: &E, cx: &mut WindowContext| {
2634 view.update(cx, |view, cx| f(view, e, cx)).ok();
2635 }
2636 }
2637}
2638
2639impl<V> Context for ViewContext<'_, V> {
2640 type Result<U> = U;
2641
2642 fn build_model<T: 'static>(
2643 &mut self,
2644 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
2645 ) -> Model<T> {
2646 self.window_cx.build_model(build_model)
2647 }
2648
2649 fn update_model<T: 'static, R>(
2650 &mut self,
2651 model: &Model<T>,
2652 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
2653 ) -> R {
2654 self.window_cx.update_model(model, update)
2655 }
2656
2657 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
2658 where
2659 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
2660 {
2661 self.window_cx.update_window(window, update)
2662 }
2663
2664 fn read_model<T, R>(
2665 &self,
2666 handle: &Model<T>,
2667 read: impl FnOnce(&T, &AppContext) -> R,
2668 ) -> Self::Result<R>
2669 where
2670 T: 'static,
2671 {
2672 self.window_cx.read_model(handle, read)
2673 }
2674
2675 fn read_window<T, R>(
2676 &self,
2677 window: &WindowHandle<T>,
2678 read: impl FnOnce(View<T>, &AppContext) -> R,
2679 ) -> Result<R>
2680 where
2681 T: 'static,
2682 {
2683 self.window_cx.read_window(window, read)
2684 }
2685}
2686
2687impl<V: 'static> VisualContext for ViewContext<'_, V> {
2688 fn build_view<W: Render + 'static>(
2689 &mut self,
2690 build_view_state: impl FnOnce(&mut ViewContext<'_, W>) -> W,
2691 ) -> Self::Result<View<W>> {
2692 self.window_cx.build_view(build_view_state)
2693 }
2694
2695 fn update_view<V2: 'static, R>(
2696 &mut self,
2697 view: &View<V2>,
2698 update: impl FnOnce(&mut V2, &mut ViewContext<'_, V2>) -> R,
2699 ) -> Self::Result<R> {
2700 self.window_cx.update_view(view, update)
2701 }
2702
2703 fn replace_root_view<W>(
2704 &mut self,
2705 build_view: impl FnOnce(&mut ViewContext<'_, W>) -> W,
2706 ) -> Self::Result<View<W>>
2707 where
2708 W: 'static + Render,
2709 {
2710 self.window_cx.replace_root_view(build_view)
2711 }
2712
2713 fn focus_view<W: FocusableView>(&mut self, view: &View<W>) -> Self::Result<()> {
2714 self.window_cx.focus_view(view)
2715 }
2716
2717 fn dismiss_view<W: ManagedView>(&mut self, view: &View<W>) -> Self::Result<()> {
2718 self.window_cx.dismiss_view(view)
2719 }
2720}
2721
2722impl<'a, V> std::ops::Deref for ViewContext<'a, V> {
2723 type Target = WindowContext<'a>;
2724
2725 fn deref(&self) -> &Self::Target {
2726 &self.window_cx
2727 }
2728}
2729
2730impl<'a, V> std::ops::DerefMut for ViewContext<'a, V> {
2731 fn deref_mut(&mut self) -> &mut Self::Target {
2732 &mut self.window_cx
2733 }
2734}
2735
2736// #[derive(Clone, Copy, Eq, PartialEq, Hash)]
2737slotmap::new_key_type! { pub struct WindowId; }
2738
2739impl WindowId {
2740 pub fn as_u64(&self) -> u64 {
2741 self.0.as_ffi()
2742 }
2743}
2744
2745#[derive(Deref, DerefMut)]
2746pub struct WindowHandle<V> {
2747 #[deref]
2748 #[deref_mut]
2749 pub(crate) any_handle: AnyWindowHandle,
2750 state_type: PhantomData<V>,
2751}
2752
2753impl<V: 'static + Render> WindowHandle<V> {
2754 pub fn new(id: WindowId) -> Self {
2755 WindowHandle {
2756 any_handle: AnyWindowHandle {
2757 id,
2758 state_type: TypeId::of::<V>(),
2759 },
2760 state_type: PhantomData,
2761 }
2762 }
2763
2764 pub fn root<C>(&self, cx: &mut C) -> Result<View<V>>
2765 where
2766 C: Context,
2767 {
2768 Flatten::flatten(cx.update_window(self.any_handle, |root_view, _| {
2769 root_view
2770 .downcast::<V>()
2771 .map_err(|_| anyhow!("the type of the window's root view has changed"))
2772 }))
2773 }
2774
2775 pub fn update<C, R>(
2776 &self,
2777 cx: &mut C,
2778 update: impl FnOnce(&mut V, &mut ViewContext<'_, V>) -> R,
2779 ) -> Result<R>
2780 where
2781 C: Context,
2782 {
2783 cx.update_window(self.any_handle, |root_view, cx| {
2784 let view = root_view
2785 .downcast::<V>()
2786 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
2787 Ok(cx.update_view(&view, update))
2788 })?
2789 }
2790
2791 pub fn read<'a>(&self, cx: &'a AppContext) -> Result<&'a V> {
2792 let x = cx
2793 .windows
2794 .get(self.id)
2795 .and_then(|window| {
2796 window
2797 .as_ref()
2798 .and_then(|window| window.root_view.clone())
2799 .map(|root_view| root_view.downcast::<V>())
2800 })
2801 .ok_or_else(|| anyhow!("window not found"))?
2802 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
2803
2804 Ok(x.read(cx))
2805 }
2806
2807 pub fn read_with<C, R>(&self, cx: &C, read_with: impl FnOnce(&V, &AppContext) -> R) -> Result<R>
2808 where
2809 C: Context,
2810 {
2811 cx.read_window(self, |root_view, cx| read_with(root_view.read(cx), cx))
2812 }
2813
2814 pub fn root_view<C>(&self, cx: &C) -> Result<View<V>>
2815 where
2816 C: Context,
2817 {
2818 cx.read_window(self, |root_view, _cx| root_view.clone())
2819 }
2820
2821 pub fn is_active(&self, cx: &AppContext) -> Option<bool> {
2822 cx.windows
2823 .get(self.id)
2824 .and_then(|window| window.as_ref().map(|window| window.active))
2825 }
2826}
2827
2828impl<V> Copy for WindowHandle<V> {}
2829
2830impl<V> Clone for WindowHandle<V> {
2831 fn clone(&self) -> Self {
2832 WindowHandle {
2833 any_handle: self.any_handle,
2834 state_type: PhantomData,
2835 }
2836 }
2837}
2838
2839impl<V> PartialEq for WindowHandle<V> {
2840 fn eq(&self, other: &Self) -> bool {
2841 self.any_handle == other.any_handle
2842 }
2843}
2844
2845impl<V> Eq for WindowHandle<V> {}
2846
2847impl<V> Hash for WindowHandle<V> {
2848 fn hash<H: Hasher>(&self, state: &mut H) {
2849 self.any_handle.hash(state);
2850 }
2851}
2852
2853impl<V: 'static> Into<AnyWindowHandle> for WindowHandle<V> {
2854 fn into(self) -> AnyWindowHandle {
2855 self.any_handle
2856 }
2857}
2858
2859#[derive(Copy, Clone, PartialEq, Eq, Hash)]
2860pub struct AnyWindowHandle {
2861 pub(crate) id: WindowId,
2862 state_type: TypeId,
2863}
2864
2865impl AnyWindowHandle {
2866 pub fn window_id(&self) -> WindowId {
2867 self.id
2868 }
2869
2870 pub fn downcast<T: 'static>(&self) -> Option<WindowHandle<T>> {
2871 if TypeId::of::<T>() == self.state_type {
2872 Some(WindowHandle {
2873 any_handle: *self,
2874 state_type: PhantomData,
2875 })
2876 } else {
2877 None
2878 }
2879 }
2880
2881 pub fn update<C, R>(
2882 self,
2883 cx: &mut C,
2884 update: impl FnOnce(AnyView, &mut WindowContext<'_>) -> R,
2885 ) -> Result<R>
2886 where
2887 C: Context,
2888 {
2889 cx.update_window(self, update)
2890 }
2891
2892 pub fn read<T, C, R>(self, cx: &C, read: impl FnOnce(View<T>, &AppContext) -> R) -> Result<R>
2893 where
2894 C: Context,
2895 T: 'static,
2896 {
2897 let view = self
2898 .downcast::<T>()
2899 .context("the type of the window's root view has changed")?;
2900
2901 cx.read_window(&view, read)
2902 }
2903}
2904
2905#[cfg(any(test, feature = "test-support"))]
2906impl From<SmallVec<[u32; 16]>> for StackingOrder {
2907 fn from(small_vec: SmallVec<[u32; 16]>) -> Self {
2908 StackingOrder(small_vec)
2909 }
2910}
2911
2912#[derive(Clone, Debug, Eq, PartialEq, Hash)]
2913pub enum ElementId {
2914 View(EntityId),
2915 Integer(usize),
2916 Name(SharedString),
2917 FocusHandle(FocusId),
2918 NamedInteger(SharedString, usize),
2919}
2920
2921impl ElementId {
2922 pub(crate) fn from_entity_id(entity_id: EntityId) -> Self {
2923 ElementId::View(entity_id)
2924 }
2925}
2926
2927impl TryInto<SharedString> for ElementId {
2928 type Error = anyhow::Error;
2929
2930 fn try_into(self) -> anyhow::Result<SharedString> {
2931 if let ElementId::Name(name) = self {
2932 Ok(name)
2933 } else {
2934 Err(anyhow!("element id is not string"))
2935 }
2936 }
2937}
2938
2939impl From<usize> for ElementId {
2940 fn from(id: usize) -> Self {
2941 ElementId::Integer(id)
2942 }
2943}
2944
2945impl From<i32> for ElementId {
2946 fn from(id: i32) -> Self {
2947 Self::Integer(id as usize)
2948 }
2949}
2950
2951impl From<SharedString> for ElementId {
2952 fn from(name: SharedString) -> Self {
2953 ElementId::Name(name)
2954 }
2955}
2956
2957impl From<&'static str> for ElementId {
2958 fn from(name: &'static str) -> Self {
2959 ElementId::Name(name.into())
2960 }
2961}
2962
2963impl<'a> From<&'a FocusHandle> for ElementId {
2964 fn from(handle: &'a FocusHandle) -> Self {
2965 ElementId::FocusHandle(handle.id)
2966 }
2967}
2968
2969impl From<(&'static str, EntityId)> for ElementId {
2970 fn from((name, id): (&'static str, EntityId)) -> Self {
2971 ElementId::NamedInteger(name.into(), id.as_u64() as usize)
2972 }
2973}
2974
2975impl From<(&'static str, usize)> for ElementId {
2976 fn from((name, id): (&'static str, usize)) -> Self {
2977 ElementId::NamedInteger(name.into(), id)
2978 }
2979}
2980
2981impl From<(&'static str, u64)> for ElementId {
2982 fn from((name, id): (&'static str, u64)) -> Self {
2983 ElementId::NamedInteger(name.into(), id as usize)
2984 }
2985}
2986
2987/// A rectangle, to be rendered on the screen by GPUI at the given position and size.
2988pub struct PaintQuad {
2989 bounds: Bounds<Pixels>,
2990 corner_radii: Corners<Pixels>,
2991 background: Hsla,
2992 border_widths: Edges<Pixels>,
2993 border_color: Hsla,
2994}
2995
2996impl PaintQuad {
2997 /// Set the corner radii of the quad.
2998 pub fn corner_radii(self, corner_radii: impl Into<Corners<Pixels>>) -> Self {
2999 PaintQuad {
3000 corner_radii: corner_radii.into(),
3001 ..self
3002 }
3003 }
3004
3005 /// Set the border widths of the quad.
3006 pub fn border_widths(self, border_widths: impl Into<Edges<Pixels>>) -> Self {
3007 PaintQuad {
3008 border_widths: border_widths.into(),
3009 ..self
3010 }
3011 }
3012
3013 /// Set the border color of the quad.
3014 pub fn border_color(self, border_color: impl Into<Hsla>) -> Self {
3015 PaintQuad {
3016 border_color: border_color.into(),
3017 ..self
3018 }
3019 }
3020
3021 /// Set the background color of the quad.
3022 pub fn background(self, background: impl Into<Hsla>) -> Self {
3023 PaintQuad {
3024 background: background.into(),
3025 ..self
3026 }
3027 }
3028}
3029
3030/// Create a quad with the given parameters.
3031pub fn quad(
3032 bounds: Bounds<Pixels>,
3033 corner_radii: impl Into<Corners<Pixels>>,
3034 background: impl Into<Hsla>,
3035 border_widths: impl Into<Edges<Pixels>>,
3036 border_color: impl Into<Hsla>,
3037) -> PaintQuad {
3038 PaintQuad {
3039 bounds,
3040 corner_radii: corner_radii.into(),
3041 background: background.into(),
3042 border_widths: border_widths.into(),
3043 border_color: border_color.into(),
3044 }
3045}
3046
3047/// Create a filled quad with the given bounds and background color.
3048pub fn fill(bounds: impl Into<Bounds<Pixels>>, background: impl Into<Hsla>) -> PaintQuad {
3049 PaintQuad {
3050 bounds: bounds.into(),
3051 corner_radii: (0.).into(),
3052 background: background.into(),
3053 border_widths: (0.).into(),
3054 border_color: transparent_black(),
3055 }
3056}
3057
3058/// Create a rectangle outline with the given bounds, border color, and a 1px border width
3059pub fn outline(bounds: impl Into<Bounds<Pixels>>, border_color: impl Into<Hsla>) -> PaintQuad {
3060 PaintQuad {
3061 bounds: bounds.into(),
3062 corner_radii: (0.).into(),
3063 background: transparent_black(),
3064 border_widths: (1.).into(),
3065 border_color: border_color.into(),
3066 }
3067}