1use crate::{
2 arena::{Arena, ArenaRef},
3 key_dispatch::DispatchActionListener,
4 px, size, transparent_black, Action, AnyDrag, AnyView, AppContext, AsyncWindowContext,
5 AvailableSpace, Bounds, BoxShadow, Context, Corners, CursorStyle, DevicePixels, DispatchNodeId,
6 DispatchTree, DisplayId, Edges, Effect, Entity, EntityId, EventEmitter, FileDropEvent, Flatten,
7 FontId, GlobalElementId, GlyphId, Hsla, ImageData, InputEvent, IsZero, KeyBinding, KeyContext,
8 KeyDownEvent, KeystrokeEvent, LayoutId, Model, ModelContext, Modifiers, MonochromeSprite,
9 MouseButton, MouseMoveEvent, MouseUpEvent, Path, Pixels, PlatformAtlas, PlatformDisplay,
10 PlatformInputHandler, PlatformWindow, Point, PolychromeSprite, PromptLevel, Quad, Render,
11 RenderGlyphParams, RenderImageParams, RenderSvgParams, ScaledPixels, Scene, SceneBuilder,
12 Shadow, SharedString, Size, Style, SubscriberSet, Subscription, Surface, TaffyLayoutEngine,
13 Task, Underline, UnderlineStyle, View, VisualContext, WeakView, WindowBounds, WindowOptions,
14 SUBPIXEL_VARIANTS,
15};
16use anyhow::{anyhow, Context as _, Result};
17use collections::FxHashMap;
18use derive_more::{Deref, DerefMut};
19use futures::{
20 channel::{mpsc, oneshot},
21 StreamExt,
22};
23use media::core_video::CVImageBuffer;
24use parking_lot::RwLock;
25use slotmap::SlotMap;
26use smallvec::SmallVec;
27use std::{
28 any::{Any, TypeId},
29 borrow::{Borrow, BorrowMut, Cow},
30 cell::RefCell,
31 fmt::Debug,
32 future::Future,
33 hash::{Hash, Hasher},
34 marker::PhantomData,
35 mem,
36 rc::Rc,
37 sync::{
38 atomic::{AtomicUsize, Ordering::SeqCst},
39 Arc,
40 },
41};
42use util::ResultExt;
43
44const ACTIVE_DRAG_Z_INDEX: u8 = 1;
45
46/// A global stacking order, which is created by stacking successive z-index values.
47/// Each z-index will always be interpreted in the context of its parent z-index.
48#[derive(Deref, DerefMut, Clone, Debug, Ord, PartialOrd, PartialEq, Eq)]
49pub struct StackingOrder {
50 #[deref]
51 #[deref_mut]
52 z_indices: SmallVec<[u8; 64]>,
53}
54
55impl Default for StackingOrder {
56 fn default() -> Self {
57 StackingOrder {
58 z_indices: SmallVec::new(),
59 }
60 }
61}
62
63/// Represents the two different phases when dispatching events.
64#[derive(Default, Copy, Clone, Debug, Eq, PartialEq)]
65pub enum DispatchPhase {
66 /// After the capture phase comes the bubble phase, in which mouse event listeners are
67 /// invoked front to back and keyboard event listeners are invoked from the focused element
68 /// to the root of the element tree. This is the phase you'll most commonly want to use when
69 /// registering event listeners.
70 #[default]
71 Bubble,
72 /// During the initial capture phase, mouse event listeners are invoked back to front, and keyboard
73 /// listeners are invoked from the root of the tree downward toward the focused element. This phase
74 /// is used for special purposes such as clearing the "pressed" state for click events. If
75 /// you stop event propagation during this phase, you need to know what you're doing. Handlers
76 /// outside of the immediate region may rely on detecting non-local events during this phase.
77 Capture,
78}
79
80impl DispatchPhase {
81 pub fn bubble(self) -> bool {
82 self == DispatchPhase::Bubble
83 }
84
85 pub fn capture(self) -> bool {
86 self == DispatchPhase::Capture
87 }
88}
89
90type AnyObserver = Box<dyn FnMut(&mut WindowContext) -> bool + 'static>;
91type AnyMouseListener = ArenaRef<dyn FnMut(&dyn Any, DispatchPhase, &mut WindowContext) + 'static>;
92type AnyWindowFocusListener = Box<dyn FnMut(&FocusEvent, &mut WindowContext) -> bool + 'static>;
93
94struct FocusEvent {
95 previous_focus_path: SmallVec<[FocusId; 8]>,
96 current_focus_path: SmallVec<[FocusId; 8]>,
97}
98
99slotmap::new_key_type! { pub struct FocusId; }
100
101thread_local! {
102 pub(crate) static ELEMENT_ARENA: RefCell<Arena> = RefCell::new(Arena::new(4 * 1024 * 1024));
103}
104
105impl FocusId {
106 /// Obtains whether the element associated with this handle is currently focused.
107 pub fn is_focused(&self, cx: &WindowContext) -> bool {
108 cx.window.focus == Some(*self)
109 }
110
111 /// Obtains whether the element associated with this handle contains the focused
112 /// element or is itself focused.
113 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
114 cx.focused()
115 .map_or(false, |focused| self.contains(focused.id, cx))
116 }
117
118 /// Obtains whether the element associated with this handle is contained within the
119 /// focused element or is itself focused.
120 pub fn within_focused(&self, cx: &WindowContext) -> bool {
121 let focused = cx.focused();
122 focused.map_or(false, |focused| focused.id.contains(*self, cx))
123 }
124
125 /// Obtains whether this handle contains the given handle in the most recently rendered frame.
126 pub(crate) fn contains(&self, other: Self, cx: &WindowContext) -> bool {
127 cx.window
128 .rendered_frame
129 .dispatch_tree
130 .focus_contains(*self, other)
131 }
132}
133
134/// A handle which can be used to track and manipulate the focused element in a window.
135pub struct FocusHandle {
136 pub(crate) id: FocusId,
137 handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
138}
139
140impl std::fmt::Debug for FocusHandle {
141 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
142 f.write_fmt(format_args!("FocusHandle({:?})", self.id))
143 }
144}
145
146impl FocusHandle {
147 pub(crate) fn new(handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>) -> Self {
148 let id = handles.write().insert(AtomicUsize::new(1));
149 Self {
150 id,
151 handles: handles.clone(),
152 }
153 }
154
155 pub(crate) fn for_id(
156 id: FocusId,
157 handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
158 ) -> Option<Self> {
159 let lock = handles.read();
160 let ref_count = lock.get(id)?;
161 if ref_count.load(SeqCst) == 0 {
162 None
163 } else {
164 ref_count.fetch_add(1, SeqCst);
165 Some(Self {
166 id,
167 handles: handles.clone(),
168 })
169 }
170 }
171
172 /// Moves the focus to the element associated with this handle.
173 pub fn focus(&self, cx: &mut WindowContext) {
174 cx.focus(self)
175 }
176
177 /// Obtains whether the element associated with this handle is currently focused.
178 pub fn is_focused(&self, cx: &WindowContext) -> bool {
179 self.id.is_focused(cx)
180 }
181
182 /// Obtains whether the element associated with this handle contains the focused
183 /// element or is itself focused.
184 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
185 self.id.contains_focused(cx)
186 }
187
188 /// Obtains whether the element associated with this handle is contained within the
189 /// focused element or is itself focused.
190 pub fn within_focused(&self, cx: &WindowContext) -> bool {
191 self.id.within_focused(cx)
192 }
193
194 /// Obtains whether this handle contains the given handle in the most recently rendered frame.
195 pub fn contains(&self, other: &Self, cx: &WindowContext) -> bool {
196 self.id.contains(other.id, cx)
197 }
198}
199
200impl Clone for FocusHandle {
201 fn clone(&self) -> Self {
202 Self::for_id(self.id, &self.handles).unwrap()
203 }
204}
205
206impl PartialEq for FocusHandle {
207 fn eq(&self, other: &Self) -> bool {
208 self.id == other.id
209 }
210}
211
212impl Eq for FocusHandle {}
213
214impl Drop for FocusHandle {
215 fn drop(&mut self) {
216 self.handles
217 .read()
218 .get(self.id)
219 .unwrap()
220 .fetch_sub(1, SeqCst);
221 }
222}
223
224/// FocusableView allows users of your view to easily
225/// focus it (using cx.focus_view(view))
226pub trait FocusableView: 'static + Render {
227 fn focus_handle(&self, cx: &AppContext) -> FocusHandle;
228}
229
230/// ManagedView is a view (like a Modal, Popover, Menu, etc.)
231/// where the lifecycle of the view is handled by another view.
232pub trait ManagedView: FocusableView + EventEmitter<DismissEvent> {}
233
234impl<M: FocusableView + EventEmitter<DismissEvent>> ManagedView for M {}
235
236pub struct DismissEvent;
237
238// Holds the state for a specific window.
239pub struct Window {
240 pub(crate) handle: AnyWindowHandle,
241 pub(crate) removed: bool,
242 pub(crate) platform_window: Box<dyn PlatformWindow>,
243 display_id: DisplayId,
244 sprite_atlas: Arc<dyn PlatformAtlas>,
245 rem_size: Pixels,
246 viewport_size: Size<Pixels>,
247 layout_engine: Option<TaffyLayoutEngine>,
248 pub(crate) root_view: Option<AnyView>,
249 pub(crate) element_id_stack: GlobalElementId,
250 pub(crate) rendered_frame: Frame,
251 pub(crate) next_frame: Frame,
252 frame_arena: Arena,
253 pub(crate) focus_handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
254 focus_listeners: SubscriberSet<(), AnyWindowFocusListener>,
255 blur_listeners: SubscriberSet<(), AnyObserver>,
256 default_prevented: bool,
257 mouse_position: Point<Pixels>,
258 modifiers: Modifiers,
259 requested_cursor_style: Option<CursorStyle>,
260 scale_factor: f32,
261 bounds: WindowBounds,
262 bounds_observers: SubscriberSet<(), AnyObserver>,
263 active: bool,
264 pub(crate) dirty: bool,
265 pub(crate) drawing: bool,
266 activation_observers: SubscriberSet<(), AnyObserver>,
267 pub(crate) focus: Option<FocusId>,
268
269 #[cfg(any(test, feature = "test-support"))]
270 pub(crate) focus_invalidated: bool,
271}
272
273pub(crate) struct ElementStateBox {
274 inner: Box<dyn Any>,
275 #[cfg(debug_assertions)]
276 type_name: &'static str,
277}
278
279pub(crate) struct Frame {
280 focus: Option<FocusId>,
281 pub(crate) element_states: FxHashMap<GlobalElementId, ElementStateBox>,
282 mouse_listeners: FxHashMap<TypeId, Vec<(StackingOrder, AnyMouseListener)>>,
283 pub(crate) dispatch_tree: DispatchTree,
284 pub(crate) scene_builder: SceneBuilder,
285 pub(crate) depth_map: Vec<(StackingOrder, Bounds<Pixels>)>,
286 pub(crate) z_index_stack: StackingOrder,
287 content_mask_stack: Vec<ContentMask<Pixels>>,
288 element_offset_stack: Vec<Point<Pixels>>,
289}
290
291impl Frame {
292 fn new(dispatch_tree: DispatchTree) -> Self {
293 Frame {
294 focus: None,
295 element_states: FxHashMap::default(),
296 mouse_listeners: FxHashMap::default(),
297 dispatch_tree,
298 scene_builder: SceneBuilder::default(),
299 z_index_stack: StackingOrder::default(),
300 depth_map: Default::default(),
301 content_mask_stack: Vec::new(),
302 element_offset_stack: Vec::new(),
303 }
304 }
305
306 fn clear(&mut self) {
307 self.element_states.clear();
308 self.mouse_listeners.values_mut().for_each(Vec::clear);
309 self.dispatch_tree.clear();
310 self.depth_map.clear();
311 }
312
313 fn focus_path(&self) -> SmallVec<[FocusId; 8]> {
314 self.focus
315 .map(|focus_id| self.dispatch_tree.focus_path(focus_id))
316 .unwrap_or_default()
317 }
318}
319
320impl Window {
321 pub(crate) fn new(
322 handle: AnyWindowHandle,
323 options: WindowOptions,
324 cx: &mut AppContext,
325 ) -> Self {
326 let platform_window = cx.platform.open_window(
327 handle,
328 options,
329 Box::new({
330 let mut cx = cx.to_async();
331 move || handle.update(&mut cx, |_, cx| cx.draw())
332 }),
333 );
334 let display_id = platform_window.display().id();
335 let sprite_atlas = platform_window.sprite_atlas();
336 let mouse_position = platform_window.mouse_position();
337 let modifiers = platform_window.modifiers();
338 let content_size = platform_window.content_size();
339 let scale_factor = platform_window.scale_factor();
340 let bounds = platform_window.bounds();
341
342 platform_window.on_resize(Box::new({
343 let mut cx = cx.to_async();
344 move |_, _| {
345 handle
346 .update(&mut cx, |_, cx| cx.window_bounds_changed())
347 .log_err();
348 }
349 }));
350 platform_window.on_moved(Box::new({
351 let mut cx = cx.to_async();
352 move || {
353 handle
354 .update(&mut cx, |_, cx| cx.window_bounds_changed())
355 .log_err();
356 }
357 }));
358 platform_window.on_active_status_change(Box::new({
359 let mut cx = cx.to_async();
360 move |active| {
361 handle
362 .update(&mut cx, |_, cx| {
363 cx.window.active = active;
364 cx.window
365 .activation_observers
366 .clone()
367 .retain(&(), |callback| callback(cx));
368 })
369 .log_err();
370 }
371 }));
372
373 platform_window.on_input({
374 let mut cx = cx.to_async();
375 Box::new(move |event| {
376 handle
377 .update(&mut cx, |_, cx| cx.dispatch_event(event))
378 .log_err()
379 .unwrap_or(false)
380 })
381 });
382
383 Window {
384 handle,
385 removed: false,
386 platform_window,
387 display_id,
388 sprite_atlas,
389 rem_size: px(16.),
390 viewport_size: content_size,
391 layout_engine: Some(TaffyLayoutEngine::new()),
392 root_view: None,
393 element_id_stack: GlobalElementId::default(),
394 rendered_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
395 next_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
396 frame_arena: Arena::new(1 * 1024 * 1024),
397 focus_handles: Arc::new(RwLock::new(SlotMap::with_key())),
398 focus_listeners: SubscriberSet::new(),
399 blur_listeners: SubscriberSet::new(),
400 default_prevented: true,
401 mouse_position,
402 modifiers,
403 requested_cursor_style: None,
404 scale_factor,
405 bounds,
406 bounds_observers: SubscriberSet::new(),
407 active: false,
408 dirty: false,
409 drawing: false,
410 activation_observers: SubscriberSet::new(),
411 focus: None,
412
413 #[cfg(any(test, feature = "test-support"))]
414 focus_invalidated: false,
415 }
416 }
417}
418
419/// Indicates which region of the window is visible. Content falling outside of this mask will not be
420/// rendered. Currently, only rectangular content masks are supported, but we give the mask its own type
421/// to leave room to support more complex shapes in the future.
422#[derive(Clone, Debug, Default, PartialEq, Eq)]
423#[repr(C)]
424pub struct ContentMask<P: Clone + Default + Debug> {
425 pub bounds: Bounds<P>,
426}
427
428impl ContentMask<Pixels> {
429 /// Scale the content mask's pixel units by the given scaling factor.
430 pub fn scale(&self, factor: f32) -> ContentMask<ScaledPixels> {
431 ContentMask {
432 bounds: self.bounds.scale(factor),
433 }
434 }
435
436 /// Intersect the content mask with the given content mask.
437 pub fn intersect(&self, other: &Self) -> Self {
438 let bounds = self.bounds.intersect(&other.bounds);
439 ContentMask { bounds }
440 }
441}
442
443/// Provides access to application state in the context of a single window. Derefs
444/// to an `AppContext`, so you can also pass a `WindowContext` to any method that takes
445/// an `AppContext` and call any `AppContext` methods.
446pub struct WindowContext<'a> {
447 pub(crate) app: &'a mut AppContext,
448 pub(crate) window: &'a mut Window,
449}
450
451impl<'a> WindowContext<'a> {
452 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window) -> Self {
453 Self { app, window }
454 }
455
456 /// Obtain a handle to the window that belongs to this context.
457 pub fn window_handle(&self) -> AnyWindowHandle {
458 self.window.handle
459 }
460
461 /// Mark the window as dirty, scheduling it to be redrawn on the next frame.
462 pub fn notify(&mut self) {
463 if !self.window.drawing {
464 self.window.dirty = true;
465 }
466 }
467
468 /// Close this window.
469 pub fn remove_window(&mut self) {
470 self.window.removed = true;
471 }
472
473 /// Obtain a new `FocusHandle`, which allows you to track and manipulate the keyboard focus
474 /// for elements rendered within this window.
475 pub fn focus_handle(&mut self) -> FocusHandle {
476 FocusHandle::new(&self.window.focus_handles)
477 }
478
479 /// Obtain the currently focused `FocusHandle`. If no elements are focused, returns `None`.
480 pub fn focused(&self) -> Option<FocusHandle> {
481 self.window
482 .focus
483 .and_then(|id| FocusHandle::for_id(id, &self.window.focus_handles))
484 }
485
486 /// Move focus to the element associated with the given `FocusHandle`.
487 pub fn focus(&mut self, handle: &FocusHandle) {
488 if self.window.focus == Some(handle.id) {
489 return;
490 }
491
492 self.window.focus = Some(handle.id);
493 self.window
494 .rendered_frame
495 .dispatch_tree
496 .clear_pending_keystrokes();
497
498 #[cfg(any(test, feature = "test-support"))]
499 {
500 self.window.focus_invalidated = true;
501 }
502
503 self.notify();
504 }
505
506 /// Remove focus from all elements within this context's window.
507 pub fn blur(&mut self) {
508 self.window.focus = None;
509 self.notify();
510 }
511
512 pub fn dispatch_action(&mut self, action: Box<dyn Action>) {
513 let focus_handle = self.focused();
514
515 self.defer(move |cx| {
516 let node_id = focus_handle
517 .and_then(|handle| {
518 cx.window
519 .rendered_frame
520 .dispatch_tree
521 .focusable_node_id(handle.id)
522 })
523 .unwrap_or_else(|| cx.window.rendered_frame.dispatch_tree.root_node_id());
524
525 cx.propagate_event = true;
526 cx.dispatch_action_on_node(node_id, action);
527 })
528 }
529
530 pub(crate) fn dispatch_keystroke_observers(
531 &mut self,
532 event: &dyn Any,
533 action: Option<Box<dyn Action>>,
534 ) {
535 let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() else {
536 return;
537 };
538
539 self.keystroke_observers
540 .clone()
541 .retain(&(), move |callback| {
542 (callback)(
543 &KeystrokeEvent {
544 keystroke: key_down_event.keystroke.clone(),
545 action: action.as_ref().map(|action| action.boxed_clone()),
546 },
547 self,
548 );
549 true
550 });
551 }
552
553 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
554 /// that are currently on the stack to be returned to the app.
555 pub fn defer(&mut self, f: impl FnOnce(&mut WindowContext) + 'static) {
556 let handle = self.window.handle;
557 self.app.defer(move |cx| {
558 handle.update(cx, |_, cx| f(cx)).ok();
559 });
560 }
561
562 pub fn subscribe<Emitter, E, Evt>(
563 &mut self,
564 entity: &E,
565 mut on_event: impl FnMut(E, &Evt, &mut WindowContext<'_>) + 'static,
566 ) -> Subscription
567 where
568 Emitter: EventEmitter<Evt>,
569 E: Entity<Emitter>,
570 Evt: 'static,
571 {
572 let entity_id = entity.entity_id();
573 let entity = entity.downgrade();
574 let window_handle = self.window.handle;
575 let (subscription, activate) = self.app.event_listeners.insert(
576 entity_id,
577 (
578 TypeId::of::<Evt>(),
579 Box::new(move |event, cx| {
580 window_handle
581 .update(cx, |_, cx| {
582 if let Some(handle) = E::upgrade_from(&entity) {
583 let event = event.downcast_ref().expect("invalid event type");
584 on_event(handle, event, cx);
585 true
586 } else {
587 false
588 }
589 })
590 .unwrap_or(false)
591 }),
592 ),
593 );
594 self.app.defer(move |_| activate());
595 subscription
596 }
597
598 /// Create an `AsyncWindowContext`, which has a static lifetime and can be held across
599 /// await points in async code.
600 pub fn to_async(&self) -> AsyncWindowContext {
601 AsyncWindowContext::new(self.app.to_async(), self.window.handle)
602 }
603
604 /// Schedule the given closure to be run directly after the current frame is rendered.
605 pub fn on_next_frame(&mut self, callback: impl FnOnce(&mut WindowContext) + 'static) {
606 let handle = self.window.handle;
607 let display_id = self.window.display_id;
608
609 if !self.frame_consumers.contains_key(&display_id) {
610 let (tx, mut rx) = mpsc::unbounded::<()>();
611 self.platform.set_display_link_output_callback(
612 display_id,
613 Box::new(move |_current_time, _output_time| _ = tx.unbounded_send(())),
614 );
615
616 let consumer_task = self.app.spawn(|cx| async move {
617 while rx.next().await.is_some() {
618 cx.update(|cx| {
619 for callback in cx
620 .next_frame_callbacks
621 .get_mut(&display_id)
622 .unwrap()
623 .drain(..)
624 .collect::<SmallVec<[_; 32]>>()
625 {
626 callback(cx);
627 }
628 })
629 .ok();
630
631 // Flush effects, then stop the display link if no new next_frame_callbacks have been added.
632
633 cx.update(|cx| {
634 if cx.next_frame_callbacks.is_empty() {
635 cx.platform.stop_display_link(display_id);
636 }
637 })
638 .ok();
639 }
640 });
641 self.frame_consumers.insert(display_id, consumer_task);
642 }
643
644 if self.next_frame_callbacks.is_empty() {
645 self.platform.start_display_link(display_id);
646 }
647
648 self.next_frame_callbacks
649 .entry(display_id)
650 .or_default()
651 .push(Box::new(move |cx: &mut AppContext| {
652 cx.update_window(handle, |_root_view, cx| callback(cx)).ok();
653 }));
654 }
655
656 /// Spawn the future returned by the given closure on the application thread pool.
657 /// The closure is provided a handle to the current window and an `AsyncWindowContext` for
658 /// use within your future.
659 pub fn spawn<Fut, R>(&mut self, f: impl FnOnce(AsyncWindowContext) -> Fut) -> Task<R>
660 where
661 R: 'static,
662 Fut: Future<Output = R> + 'static,
663 {
664 self.app
665 .spawn(|app| f(AsyncWindowContext::new(app, self.window.handle)))
666 }
667
668 /// Update the global of the given type. The given closure is given simultaneous mutable
669 /// access both to the global and the context.
670 pub fn update_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
671 where
672 G: 'static,
673 {
674 let mut global = self.app.lease_global::<G>();
675 let result = f(&mut global, self);
676 self.app.end_global_lease(global);
677 result
678 }
679
680 #[must_use]
681 /// Add a node to the layout tree for the current frame. Takes the `Style` of the element for which
682 /// layout is being requested, along with the layout ids of any children. This method is called during
683 /// calls to the `Element::layout` trait method and enables any element to participate in layout.
684 pub fn request_layout(
685 &mut self,
686 style: &Style,
687 children: impl IntoIterator<Item = LayoutId>,
688 ) -> LayoutId {
689 self.app.layout_id_buffer.clear();
690 self.app.layout_id_buffer.extend(children.into_iter());
691 let rem_size = self.rem_size();
692
693 self.window.layout_engine.as_mut().unwrap().request_layout(
694 style,
695 rem_size,
696 &self.app.layout_id_buffer,
697 )
698 }
699
700 /// Add a node to the layout tree for the current frame. Instead of taking a `Style` and children,
701 /// this variant takes a function that is invoked during layout so you can use arbitrary logic to
702 /// determine the element's size. One place this is used internally is when measuring text.
703 ///
704 /// The given closure is invoked at layout time with the known dimensions and available space and
705 /// returns a `Size`.
706 pub fn request_measured_layout<
707 F: FnMut(Size<Option<Pixels>>, Size<AvailableSpace>, &mut WindowContext) -> Size<Pixels>
708 + 'static,
709 >(
710 &mut self,
711 style: Style,
712 measure: F,
713 ) -> LayoutId {
714 let rem_size = self.rem_size();
715 self.window
716 .layout_engine
717 .as_mut()
718 .unwrap()
719 .request_measured_layout(style, rem_size, measure)
720 }
721
722 pub fn compute_layout(&mut self, layout_id: LayoutId, available_space: Size<AvailableSpace>) {
723 let mut layout_engine = self.window.layout_engine.take().unwrap();
724 layout_engine.compute_layout(layout_id, available_space, self);
725 self.window.layout_engine = Some(layout_engine);
726 }
727
728 /// Obtain the bounds computed for the given LayoutId relative to the window. This method should not
729 /// be invoked until the paint phase begins, and will usually be invoked by GPUI itself automatically
730 /// in order to pass your element its `Bounds` automatically.
731 pub fn layout_bounds(&mut self, layout_id: LayoutId) -> Bounds<Pixels> {
732 let mut bounds = self
733 .window
734 .layout_engine
735 .as_mut()
736 .unwrap()
737 .layout_bounds(layout_id)
738 .map(Into::into);
739 bounds.origin += self.element_offset();
740 bounds
741 }
742
743 fn window_bounds_changed(&mut self) {
744 self.window.scale_factor = self.window.platform_window.scale_factor();
745 self.window.viewport_size = self.window.platform_window.content_size();
746 self.window.bounds = self.window.platform_window.bounds();
747 self.window.display_id = self.window.platform_window.display().id();
748 self.notify();
749
750 self.window
751 .bounds_observers
752 .clone()
753 .retain(&(), |callback| callback(self));
754 }
755
756 pub fn window_bounds(&self) -> WindowBounds {
757 self.window.bounds
758 }
759
760 pub fn viewport_size(&self) -> Size<Pixels> {
761 self.window.viewport_size
762 }
763
764 pub fn is_window_active(&self) -> bool {
765 self.window.active
766 }
767
768 pub fn zoom_window(&self) {
769 self.window.platform_window.zoom();
770 }
771
772 pub fn set_window_title(&mut self, title: &str) {
773 self.window.platform_window.set_title(title);
774 }
775
776 pub fn display(&self) -> Option<Rc<dyn PlatformDisplay>> {
777 self.platform
778 .displays()
779 .into_iter()
780 .find(|display| display.id() == self.window.display_id)
781 }
782
783 pub fn show_character_palette(&self) {
784 self.window.platform_window.show_character_palette();
785 }
786
787 /// The scale factor of the display associated with the window. For example, it could
788 /// return 2.0 for a "retina" display, indicating that each logical pixel should actually
789 /// be rendered as two pixels on screen.
790 pub fn scale_factor(&self) -> f32 {
791 self.window.scale_factor
792 }
793
794 /// The size of an em for the base font of the application. Adjusting this value allows the
795 /// UI to scale, just like zooming a web page.
796 pub fn rem_size(&self) -> Pixels {
797 self.window.rem_size
798 }
799
800 /// Sets the size of an em for the base font of the application. Adjusting this value allows the
801 /// UI to scale, just like zooming a web page.
802 pub fn set_rem_size(&mut self, rem_size: impl Into<Pixels>) {
803 self.window.rem_size = rem_size.into();
804 }
805
806 /// The line height associated with the current text style.
807 pub fn line_height(&self) -> Pixels {
808 let rem_size = self.rem_size();
809 let text_style = self.text_style();
810 text_style
811 .line_height
812 .to_pixels(text_style.font_size.into(), rem_size)
813 }
814
815 /// Call to prevent the default action of an event. Currently only used to prevent
816 /// parent elements from becoming focused on mouse down.
817 pub fn prevent_default(&mut self) {
818 self.window.default_prevented = true;
819 }
820
821 /// Obtain whether default has been prevented for the event currently being dispatched.
822 pub fn default_prevented(&self) -> bool {
823 self.window.default_prevented
824 }
825
826 /// Register a mouse event listener on the window for the next frame. The type of event
827 /// is determined by the first parameter of the given listener. When the next frame is rendered
828 /// the listener will be cleared.
829 pub fn on_mouse_event<Event: 'static>(
830 &mut self,
831 mut handler: impl FnMut(&Event, DispatchPhase, &mut WindowContext) + 'static,
832 ) {
833 let order = self.window.next_frame.z_index_stack.clone();
834 let handler = self
835 .window
836 .frame_arena
837 .alloc(|| {
838 move |event: &dyn Any, phase: DispatchPhase, cx: &mut WindowContext<'_>| {
839 handler(event.downcast_ref().unwrap(), phase, cx)
840 }
841 })
842 .map(|handler| handler as _);
843 self.window
844 .next_frame
845 .mouse_listeners
846 .entry(TypeId::of::<Event>())
847 .or_default()
848 .push((order, handler))
849 }
850
851 /// Register a key event listener on the window for the next frame. The type of event
852 /// is determined by the first parameter of the given listener. When the next frame is rendered
853 /// the listener will be cleared.
854 ///
855 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
856 /// a specific need to register a global listener.
857 pub fn on_key_event<Event: 'static>(
858 &mut self,
859 listener: impl Fn(&Event, DispatchPhase, &mut WindowContext) + 'static,
860 ) {
861 let listener = self
862 .window
863 .frame_arena
864 .alloc(|| {
865 move |event: &dyn Any, phase, cx: &mut WindowContext<'_>| {
866 if let Some(event) = event.downcast_ref::<Event>() {
867 listener(event, phase, cx)
868 }
869 }
870 })
871 .map(|handler| handler as _);
872 self.window.next_frame.dispatch_tree.on_key_event(listener);
873 }
874
875 /// Register an action listener on the window for the next frame. The type of action
876 /// is determined by the first parameter of the given listener. When the next frame is rendered
877 /// the listener will be cleared.
878 ///
879 /// This is a fairly low-level method, so prefer using action handlers on elements unless you have
880 /// a specific need to register a global listener.
881 pub fn on_action(
882 &mut self,
883 action_type: TypeId,
884 listener: impl Fn(&dyn Any, DispatchPhase, &mut WindowContext) + 'static,
885 ) {
886 let listener = self
887 .window
888 .frame_arena
889 .alloc(|| listener)
890 .map(|handler| handler as _);
891 self.window
892 .next_frame
893 .dispatch_tree
894 .on_action(action_type, listener);
895 }
896
897 pub fn is_action_available(&self, action: &dyn Action) -> bool {
898 let target = self
899 .focused()
900 .and_then(|focused_handle| {
901 self.window
902 .rendered_frame
903 .dispatch_tree
904 .focusable_node_id(focused_handle.id)
905 })
906 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
907 self.window
908 .rendered_frame
909 .dispatch_tree
910 .is_action_available(action, target)
911 }
912
913 /// The position of the mouse relative to the window.
914 pub fn mouse_position(&self) -> Point<Pixels> {
915 self.window.mouse_position
916 }
917
918 /// The current state of the keyboard's modifiers
919 pub fn modifiers(&self) -> Modifiers {
920 self.window.modifiers
921 }
922
923 pub fn set_cursor_style(&mut self, style: CursorStyle) {
924 self.window.requested_cursor_style = Some(style)
925 }
926
927 /// Called during painting to invoke the given closure in a new stacking context. The given
928 /// z-index is interpreted relative to the previous call to `stack`.
929 pub fn with_z_index<R>(&mut self, z_index: u8, f: impl FnOnce(&mut Self) -> R) -> R {
930 self.window.next_frame.z_index_stack.push(z_index);
931 let result = f(self);
932 self.window.next_frame.z_index_stack.pop();
933 result
934 }
935
936 /// Called during painting to track which z-index is on top at each pixel position
937 pub fn add_opaque_layer(&mut self, bounds: Bounds<Pixels>) {
938 let stacking_order = self.window.next_frame.z_index_stack.clone();
939 let depth_map = &mut self.window.next_frame.depth_map;
940 match depth_map.binary_search_by(|(level, _)| stacking_order.cmp(&level)) {
941 Ok(i) | Err(i) => depth_map.insert(i, (stacking_order, bounds)),
942 }
943 }
944
945 /// Returns true if the top-most opaque layer painted over this point was part of the
946 /// same layer as the given stacking order.
947 pub fn was_top_layer(&self, point: &Point<Pixels>, level: &StackingOrder) -> bool {
948 for (stack, bounds) in self.window.rendered_frame.depth_map.iter() {
949 if bounds.contains(point) {
950 return level.starts_with(stack) || stack.starts_with(level);
951 }
952 }
953
954 false
955 }
956
957 pub fn was_top_layer_under_active_drag(
958 &self,
959 point: &Point<Pixels>,
960 level: &StackingOrder,
961 ) -> bool {
962 for (stack, bounds) in self.window.rendered_frame.depth_map.iter() {
963 if stack.starts_with(&[ACTIVE_DRAG_Z_INDEX]) {
964 continue;
965 }
966 if bounds.contains(point) {
967 return level.starts_with(stack) || stack.starts_with(level);
968 }
969 }
970
971 false
972 }
973
974 /// Called during painting to get the current stacking order.
975 pub fn stacking_order(&self) -> &StackingOrder {
976 &self.window.next_frame.z_index_stack
977 }
978
979 /// Paint one or more drop shadows into the scene for the next frame at the current z-index.
980 pub fn paint_shadows(
981 &mut self,
982 bounds: Bounds<Pixels>,
983 corner_radii: Corners<Pixels>,
984 shadows: &[BoxShadow],
985 ) {
986 let scale_factor = self.scale_factor();
987 let content_mask = self.content_mask();
988 let window = &mut *self.window;
989 for shadow in shadows {
990 let mut shadow_bounds = bounds;
991 shadow_bounds.origin += shadow.offset;
992 shadow_bounds.dilate(shadow.spread_radius);
993 window.next_frame.scene_builder.insert(
994 &window.next_frame.z_index_stack,
995 Shadow {
996 order: 0,
997 bounds: shadow_bounds.scale(scale_factor),
998 content_mask: content_mask.scale(scale_factor),
999 corner_radii: corner_radii.scale(scale_factor),
1000 color: shadow.color,
1001 blur_radius: shadow.blur_radius.scale(scale_factor),
1002 },
1003 );
1004 }
1005 }
1006
1007 /// Paint one or more quads into the scene for the next frame at the current stacking context.
1008 /// Quads are colored rectangular regions with an optional background, border, and corner radius.
1009 /// see [`fill`], [`outline`], and [`quad`] to construct this type.
1010 pub fn paint_quad(&mut self, quad: PaintQuad) {
1011 let scale_factor = self.scale_factor();
1012 let content_mask = self.content_mask();
1013
1014 let window = &mut *self.window;
1015 window.next_frame.scene_builder.insert(
1016 &window.next_frame.z_index_stack,
1017 Quad {
1018 order: 0,
1019 bounds: quad.bounds.scale(scale_factor),
1020 content_mask: content_mask.scale(scale_factor),
1021 background: quad.background,
1022 border_color: quad.border_color,
1023 corner_radii: quad.corner_radii.scale(scale_factor),
1024 border_widths: quad.border_widths.scale(scale_factor),
1025 },
1026 );
1027 }
1028
1029 /// Paint the given `Path` into the scene for the next frame at the current z-index.
1030 pub fn paint_path(&mut self, mut path: Path<Pixels>, color: impl Into<Hsla>) {
1031 let scale_factor = self.scale_factor();
1032 let content_mask = self.content_mask();
1033 path.content_mask = content_mask;
1034 path.color = color.into();
1035 let window = &mut *self.window;
1036 window
1037 .next_frame
1038 .scene_builder
1039 .insert(&window.next_frame.z_index_stack, path.scale(scale_factor));
1040 }
1041
1042 /// Paint an underline into the scene for the next frame at the current z-index.
1043 pub fn paint_underline(
1044 &mut self,
1045 origin: Point<Pixels>,
1046 width: Pixels,
1047 style: &UnderlineStyle,
1048 ) {
1049 let scale_factor = self.scale_factor();
1050 let height = if style.wavy {
1051 style.thickness * 3.
1052 } else {
1053 style.thickness
1054 };
1055 let bounds = Bounds {
1056 origin,
1057 size: size(width, height),
1058 };
1059 let content_mask = self.content_mask();
1060 let window = &mut *self.window;
1061 window.next_frame.scene_builder.insert(
1062 &window.next_frame.z_index_stack,
1063 Underline {
1064 order: 0,
1065 bounds: bounds.scale(scale_factor),
1066 content_mask: content_mask.scale(scale_factor),
1067 thickness: style.thickness.scale(scale_factor),
1068 color: style.color.unwrap_or_default(),
1069 wavy: style.wavy,
1070 },
1071 );
1072 }
1073
1074 /// Paint a monochrome (non-emoji) glyph into the scene for the next frame at the current z-index.
1075 /// The y component of the origin is the baseline of the glyph.
1076 pub fn paint_glyph(
1077 &mut self,
1078 origin: Point<Pixels>,
1079 font_id: FontId,
1080 glyph_id: GlyphId,
1081 font_size: Pixels,
1082 color: Hsla,
1083 ) -> Result<()> {
1084 let scale_factor = self.scale_factor();
1085 let glyph_origin = origin.scale(scale_factor);
1086 let subpixel_variant = Point {
1087 x: (glyph_origin.x.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
1088 y: (glyph_origin.y.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
1089 };
1090 let params = RenderGlyphParams {
1091 font_id,
1092 glyph_id,
1093 font_size,
1094 subpixel_variant,
1095 scale_factor,
1096 is_emoji: false,
1097 };
1098
1099 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
1100 if !raster_bounds.is_zero() {
1101 let tile =
1102 self.window
1103 .sprite_atlas
1104 .get_or_insert_with(¶ms.clone().into(), &mut || {
1105 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
1106 Ok((size, Cow::Owned(bytes)))
1107 })?;
1108 let bounds = Bounds {
1109 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
1110 size: tile.bounds.size.map(Into::into),
1111 };
1112 let content_mask = self.content_mask().scale(scale_factor);
1113 let window = &mut *self.window;
1114 window.next_frame.scene_builder.insert(
1115 &window.next_frame.z_index_stack,
1116 MonochromeSprite {
1117 order: 0,
1118 bounds,
1119 content_mask,
1120 color,
1121 tile,
1122 },
1123 );
1124 }
1125 Ok(())
1126 }
1127
1128 /// Paint an emoji glyph into the scene for the next frame at the current z-index.
1129 /// The y component of the origin is the baseline of the glyph.
1130 pub fn paint_emoji(
1131 &mut self,
1132 origin: Point<Pixels>,
1133 font_id: FontId,
1134 glyph_id: GlyphId,
1135 font_size: Pixels,
1136 ) -> Result<()> {
1137 let scale_factor = self.scale_factor();
1138 let glyph_origin = origin.scale(scale_factor);
1139 let params = RenderGlyphParams {
1140 font_id,
1141 glyph_id,
1142 font_size,
1143 // We don't render emojis with subpixel variants.
1144 subpixel_variant: Default::default(),
1145 scale_factor,
1146 is_emoji: true,
1147 };
1148
1149 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
1150 if !raster_bounds.is_zero() {
1151 let tile =
1152 self.window
1153 .sprite_atlas
1154 .get_or_insert_with(¶ms.clone().into(), &mut || {
1155 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
1156 Ok((size, Cow::Owned(bytes)))
1157 })?;
1158 let bounds = Bounds {
1159 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
1160 size: tile.bounds.size.map(Into::into),
1161 };
1162 let content_mask = self.content_mask().scale(scale_factor);
1163 let window = &mut *self.window;
1164
1165 window.next_frame.scene_builder.insert(
1166 &window.next_frame.z_index_stack,
1167 PolychromeSprite {
1168 order: 0,
1169 bounds,
1170 corner_radii: Default::default(),
1171 content_mask,
1172 tile,
1173 grayscale: false,
1174 },
1175 );
1176 }
1177 Ok(())
1178 }
1179
1180 /// Paint a monochrome SVG into the scene for the next frame at the current stacking context.
1181 pub fn paint_svg(
1182 &mut self,
1183 bounds: Bounds<Pixels>,
1184 path: SharedString,
1185 color: Hsla,
1186 ) -> Result<()> {
1187 let scale_factor = self.scale_factor();
1188 let bounds = bounds.scale(scale_factor);
1189 // Render the SVG at twice the size to get a higher quality result.
1190 let params = RenderSvgParams {
1191 path,
1192 size: bounds
1193 .size
1194 .map(|pixels| DevicePixels::from((pixels.0 * 2.).ceil() as i32)),
1195 };
1196
1197 let tile =
1198 self.window
1199 .sprite_atlas
1200 .get_or_insert_with(¶ms.clone().into(), &mut || {
1201 let bytes = self.svg_renderer.render(¶ms)?;
1202 Ok((params.size, Cow::Owned(bytes)))
1203 })?;
1204 let content_mask = self.content_mask().scale(scale_factor);
1205
1206 let window = &mut *self.window;
1207 window.next_frame.scene_builder.insert(
1208 &window.next_frame.z_index_stack,
1209 MonochromeSprite {
1210 order: 0,
1211 bounds,
1212 content_mask,
1213 color,
1214 tile,
1215 },
1216 );
1217
1218 Ok(())
1219 }
1220
1221 /// Paint an image into the scene for the next frame at the current z-index.
1222 pub fn paint_image(
1223 &mut self,
1224 bounds: Bounds<Pixels>,
1225 corner_radii: Corners<Pixels>,
1226 data: Arc<ImageData>,
1227 grayscale: bool,
1228 ) -> Result<()> {
1229 let scale_factor = self.scale_factor();
1230 let bounds = bounds.scale(scale_factor);
1231 let params = RenderImageParams { image_id: data.id };
1232
1233 let tile = self
1234 .window
1235 .sprite_atlas
1236 .get_or_insert_with(¶ms.clone().into(), &mut || {
1237 Ok((data.size(), Cow::Borrowed(data.as_bytes())))
1238 })?;
1239 let content_mask = self.content_mask().scale(scale_factor);
1240 let corner_radii = corner_radii.scale(scale_factor);
1241
1242 let window = &mut *self.window;
1243 window.next_frame.scene_builder.insert(
1244 &window.next_frame.z_index_stack,
1245 PolychromeSprite {
1246 order: 0,
1247 bounds,
1248 content_mask,
1249 corner_radii,
1250 tile,
1251 grayscale,
1252 },
1253 );
1254 Ok(())
1255 }
1256
1257 /// Paint a surface into the scene for the next frame at the current z-index.
1258 pub fn paint_surface(&mut self, bounds: Bounds<Pixels>, image_buffer: CVImageBuffer) {
1259 let scale_factor = self.scale_factor();
1260 let bounds = bounds.scale(scale_factor);
1261 let content_mask = self.content_mask().scale(scale_factor);
1262 let window = &mut *self.window;
1263 window.next_frame.scene_builder.insert(
1264 &window.next_frame.z_index_stack,
1265 Surface {
1266 order: 0,
1267 bounds,
1268 content_mask,
1269 image_buffer,
1270 },
1271 );
1272 }
1273
1274 /// Draw pixels to the display for this window based on the contents of its scene.
1275 pub(crate) fn draw(&mut self) -> Scene {
1276 self.window.dirty = false;
1277 self.window.drawing = true;
1278
1279 #[cfg(any(test, feature = "test-support"))]
1280 {
1281 self.window.focus_invalidated = false;
1282 }
1283
1284 self.text_system().start_frame();
1285 self.window.platform_window.clear_input_handler();
1286 self.window.layout_engine.as_mut().unwrap().clear();
1287 self.window.next_frame.clear();
1288 self.window.frame_arena.clear();
1289 let root_view = self.window.root_view.take().unwrap();
1290
1291 self.with_z_index(0, |cx| {
1292 cx.with_key_dispatch(Some(KeyContext::default()), None, |_, cx| {
1293 for (action_type, action_listeners) in &cx.app.global_action_listeners {
1294 for action_listener in action_listeners.iter().cloned() {
1295 let listener = cx
1296 .window
1297 .frame_arena
1298 .alloc(|| {
1299 move |action: &dyn Any, phase, cx: &mut WindowContext<'_>| {
1300 action_listener(action, phase, cx)
1301 }
1302 })
1303 .map(|listener| listener as _);
1304 cx.window
1305 .next_frame
1306 .dispatch_tree
1307 .on_action(*action_type, listener)
1308 }
1309 }
1310
1311 let available_space = cx.window.viewport_size.map(Into::into);
1312 root_view.draw(Point::default(), available_space, cx);
1313 })
1314 });
1315
1316 if let Some(active_drag) = self.app.active_drag.take() {
1317 self.with_z_index(ACTIVE_DRAG_Z_INDEX, |cx| {
1318 let offset = cx.mouse_position() - active_drag.cursor_offset;
1319 let available_space = size(AvailableSpace::MinContent, AvailableSpace::MinContent);
1320 active_drag.view.draw(offset, available_space, cx);
1321 });
1322 self.active_drag = Some(active_drag);
1323 } else if let Some(active_tooltip) = self.app.active_tooltip.take() {
1324 self.with_z_index(1, |cx| {
1325 let available_space = size(AvailableSpace::MinContent, AvailableSpace::MinContent);
1326 active_tooltip
1327 .view
1328 .draw(active_tooltip.cursor_offset, available_space, cx);
1329 });
1330 }
1331
1332 self.window
1333 .next_frame
1334 .dispatch_tree
1335 .preserve_pending_keystrokes(
1336 &mut self.window.rendered_frame.dispatch_tree,
1337 self.window.focus,
1338 );
1339 self.window.next_frame.focus = self.window.focus;
1340 self.window.root_view = Some(root_view);
1341
1342 let previous_focus_path = self.window.rendered_frame.focus_path();
1343 mem::swap(&mut self.window.rendered_frame, &mut self.window.next_frame);
1344 let current_focus_path = self.window.rendered_frame.focus_path();
1345
1346 if previous_focus_path != current_focus_path {
1347 if !previous_focus_path.is_empty() && current_focus_path.is_empty() {
1348 self.window
1349 .blur_listeners
1350 .clone()
1351 .retain(&(), |listener| listener(self));
1352 }
1353
1354 let event = FocusEvent {
1355 previous_focus_path,
1356 current_focus_path,
1357 };
1358 self.window
1359 .focus_listeners
1360 .clone()
1361 .retain(&(), |listener| listener(&event, self));
1362 }
1363
1364 let scene = self.window.rendered_frame.scene_builder.build();
1365
1366 // Set the cursor only if we're the active window.
1367 let cursor_style = self
1368 .window
1369 .requested_cursor_style
1370 .take()
1371 .unwrap_or(CursorStyle::Arrow);
1372 if self.is_window_active() {
1373 self.platform.set_cursor_style(cursor_style);
1374 }
1375
1376 self.window.drawing = false;
1377 ELEMENT_ARENA.with_borrow_mut(|element_arena| element_arena.clear());
1378
1379 scene
1380 }
1381
1382 /// Dispatch a mouse or keyboard event on the window.
1383 pub fn dispatch_event(&mut self, event: InputEvent) -> bool {
1384 // Handlers may set this to false by calling `stop_propagation`.
1385 self.app.propagate_event = true;
1386 // Handlers may set this to true by calling `prevent_default`.
1387 self.window.default_prevented = false;
1388
1389 let event = match event {
1390 // Track the mouse position with our own state, since accessing the platform
1391 // API for the mouse position can only occur on the main thread.
1392 InputEvent::MouseMove(mouse_move) => {
1393 self.window.mouse_position = mouse_move.position;
1394 self.window.modifiers = mouse_move.modifiers;
1395 InputEvent::MouseMove(mouse_move)
1396 }
1397 InputEvent::MouseDown(mouse_down) => {
1398 self.window.mouse_position = mouse_down.position;
1399 self.window.modifiers = mouse_down.modifiers;
1400 InputEvent::MouseDown(mouse_down)
1401 }
1402 InputEvent::MouseUp(mouse_up) => {
1403 self.window.mouse_position = mouse_up.position;
1404 self.window.modifiers = mouse_up.modifiers;
1405 InputEvent::MouseUp(mouse_up)
1406 }
1407 InputEvent::MouseExited(mouse_exited) => {
1408 // todo!("Should we record that the mouse is outside of the window somehow? Or are these global pixels?")
1409 self.window.modifiers = mouse_exited.modifiers;
1410
1411 InputEvent::MouseExited(mouse_exited)
1412 }
1413 InputEvent::ModifiersChanged(modifiers_changed) => {
1414 self.window.modifiers = modifiers_changed.modifiers;
1415 InputEvent::ModifiersChanged(modifiers_changed)
1416 }
1417 InputEvent::ScrollWheel(scroll_wheel) => {
1418 self.window.mouse_position = scroll_wheel.position;
1419 self.window.modifiers = scroll_wheel.modifiers;
1420 InputEvent::ScrollWheel(scroll_wheel)
1421 }
1422 // Translate dragging and dropping of external files from the operating system
1423 // to internal drag and drop events.
1424 InputEvent::FileDrop(file_drop) => match file_drop {
1425 FileDropEvent::Entered { position, files } => {
1426 self.window.mouse_position = position;
1427 if self.active_drag.is_none() {
1428 self.active_drag = Some(AnyDrag {
1429 value: Box::new(files.clone()),
1430 view: self.build_view(|_| files).into(),
1431 cursor_offset: position,
1432 });
1433 }
1434 InputEvent::MouseMove(MouseMoveEvent {
1435 position,
1436 pressed_button: Some(MouseButton::Left),
1437 modifiers: Modifiers::default(),
1438 })
1439 }
1440 FileDropEvent::Pending { position } => {
1441 self.window.mouse_position = position;
1442 InputEvent::MouseMove(MouseMoveEvent {
1443 position,
1444 pressed_button: Some(MouseButton::Left),
1445 modifiers: Modifiers::default(),
1446 })
1447 }
1448 FileDropEvent::Submit { position } => {
1449 self.activate(true);
1450 self.window.mouse_position = position;
1451 InputEvent::MouseUp(MouseUpEvent {
1452 button: MouseButton::Left,
1453 position,
1454 modifiers: Modifiers::default(),
1455 click_count: 1,
1456 })
1457 }
1458 FileDropEvent::Exited => InputEvent::MouseUp(MouseUpEvent {
1459 button: MouseButton::Left,
1460 position: Point::default(),
1461 modifiers: Modifiers::default(),
1462 click_count: 1,
1463 }),
1464 },
1465 InputEvent::KeyDown(_) | InputEvent::KeyUp(_) => event,
1466 };
1467
1468 if let Some(any_mouse_event) = event.mouse_event() {
1469 self.dispatch_mouse_event(any_mouse_event);
1470 } else if let Some(any_key_event) = event.keyboard_event() {
1471 self.dispatch_key_event(any_key_event);
1472 }
1473
1474 !self.app.propagate_event
1475 }
1476
1477 fn dispatch_mouse_event(&mut self, event: &dyn Any) {
1478 if let Some(mut handlers) = self
1479 .window
1480 .rendered_frame
1481 .mouse_listeners
1482 .remove(&event.type_id())
1483 {
1484 // Because handlers may add other handlers, we sort every time.
1485 handlers.sort_by(|(a, _), (b, _)| a.cmp(b));
1486
1487 // Capture phase, events bubble from back to front. Handlers for this phase are used for
1488 // special purposes, such as detecting events outside of a given Bounds.
1489 for (_, handler) in &mut handlers {
1490 handler(event, DispatchPhase::Capture, self);
1491 if !self.app.propagate_event {
1492 break;
1493 }
1494 }
1495
1496 // Bubble phase, where most normal handlers do their work.
1497 if self.app.propagate_event {
1498 for (_, handler) in handlers.iter_mut().rev() {
1499 handler(event, DispatchPhase::Bubble, self);
1500 if !self.app.propagate_event {
1501 break;
1502 }
1503 }
1504 }
1505
1506 if self.app.propagate_event && event.downcast_ref::<MouseUpEvent>().is_some() {
1507 self.active_drag = None;
1508 }
1509
1510 self.window
1511 .rendered_frame
1512 .mouse_listeners
1513 .insert(event.type_id(), handlers);
1514 }
1515 }
1516
1517 fn dispatch_key_event(&mut self, event: &dyn Any) {
1518 let node_id = self
1519 .window
1520 .focus
1521 .and_then(|focus_id| {
1522 self.window
1523 .rendered_frame
1524 .dispatch_tree
1525 .focusable_node_id(focus_id)
1526 })
1527 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
1528
1529 let dispatch_path = self
1530 .window
1531 .rendered_frame
1532 .dispatch_tree
1533 .dispatch_path(node_id);
1534
1535 let mut actions: Vec<Box<dyn Action>> = Vec::new();
1536
1537 // Capture phase
1538 let mut context_stack: SmallVec<[KeyContext; 16]> = SmallVec::new();
1539 self.propagate_event = true;
1540
1541 for node_id in &dispatch_path {
1542 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1543
1544 if let Some(context) = node.context.clone() {
1545 context_stack.push(context);
1546 }
1547
1548 for key_listener in node.key_listeners.clone() {
1549 key_listener(event, DispatchPhase::Capture, self);
1550 if !self.propagate_event {
1551 return;
1552 }
1553 }
1554 }
1555
1556 // Bubble phase
1557 for node_id in dispatch_path.iter().rev() {
1558 // Handle low level key events
1559 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1560 for key_listener in node.key_listeners.clone() {
1561 key_listener(event, DispatchPhase::Bubble, self);
1562 if !self.propagate_event {
1563 return;
1564 }
1565 }
1566
1567 // Match keystrokes
1568 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1569 if node.context.is_some() {
1570 if let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() {
1571 let mut new_actions = self
1572 .window
1573 .rendered_frame
1574 .dispatch_tree
1575 .dispatch_key(&key_down_event.keystroke, &context_stack);
1576 actions.append(&mut new_actions);
1577 }
1578
1579 context_stack.pop();
1580 }
1581 }
1582
1583 for action in actions {
1584 self.dispatch_action_on_node(node_id, action.boxed_clone());
1585 if !self.propagate_event {
1586 self.dispatch_keystroke_observers(event, Some(action));
1587 return;
1588 }
1589 }
1590 self.dispatch_keystroke_observers(event, None);
1591 }
1592
1593 pub fn has_pending_keystrokes(&self) -> bool {
1594 self.window
1595 .rendered_frame
1596 .dispatch_tree
1597 .has_pending_keystrokes()
1598 }
1599
1600 fn dispatch_action_on_node(&mut self, node_id: DispatchNodeId, action: Box<dyn Action>) {
1601 let dispatch_path = self
1602 .window
1603 .rendered_frame
1604 .dispatch_tree
1605 .dispatch_path(node_id);
1606
1607 // Capture phase
1608 for node_id in &dispatch_path {
1609 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1610 for DispatchActionListener {
1611 action_type,
1612 listener,
1613 } in node.action_listeners.clone()
1614 {
1615 let any_action = action.as_any();
1616 if action_type == any_action.type_id() {
1617 listener(any_action, DispatchPhase::Capture, self);
1618 if !self.propagate_event {
1619 return;
1620 }
1621 }
1622 }
1623 }
1624 // Bubble phase
1625 for node_id in dispatch_path.iter().rev() {
1626 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1627 for DispatchActionListener {
1628 action_type,
1629 listener,
1630 } in node.action_listeners.clone()
1631 {
1632 let any_action = action.as_any();
1633 if action_type == any_action.type_id() {
1634 self.propagate_event = false; // Actions stop propagation by default during the bubble phase
1635 listener(any_action, DispatchPhase::Bubble, self);
1636 if !self.propagate_event {
1637 return;
1638 }
1639 }
1640 }
1641 }
1642 }
1643
1644 /// Register the given handler to be invoked whenever the global of the given type
1645 /// is updated.
1646 pub fn observe_global<G: 'static>(
1647 &mut self,
1648 f: impl Fn(&mut WindowContext<'_>) + 'static,
1649 ) -> Subscription {
1650 let window_handle = self.window.handle;
1651 let (subscription, activate) = self.global_observers.insert(
1652 TypeId::of::<G>(),
1653 Box::new(move |cx| window_handle.update(cx, |_, cx| f(cx)).is_ok()),
1654 );
1655 self.app.defer(move |_| activate());
1656 subscription
1657 }
1658
1659 pub fn activate_window(&self) {
1660 self.window.platform_window.activate();
1661 }
1662
1663 pub fn minimize_window(&self) {
1664 self.window.platform_window.minimize();
1665 }
1666
1667 pub fn toggle_full_screen(&self) {
1668 self.window.platform_window.toggle_full_screen();
1669 }
1670
1671 pub fn prompt(
1672 &self,
1673 level: PromptLevel,
1674 msg: &str,
1675 answers: &[&str],
1676 ) -> oneshot::Receiver<usize> {
1677 self.window.platform_window.prompt(level, msg, answers)
1678 }
1679
1680 pub fn available_actions(&self) -> Vec<Box<dyn Action>> {
1681 let node_id = self
1682 .window
1683 .focus
1684 .and_then(|focus_id| {
1685 self.window
1686 .rendered_frame
1687 .dispatch_tree
1688 .focusable_node_id(focus_id)
1689 })
1690 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
1691
1692 self.window
1693 .rendered_frame
1694 .dispatch_tree
1695 .available_actions(node_id)
1696 }
1697
1698 pub fn bindings_for_action(&self, action: &dyn Action) -> Vec<KeyBinding> {
1699 self.window
1700 .rendered_frame
1701 .dispatch_tree
1702 .bindings_for_action(
1703 action,
1704 &self.window.rendered_frame.dispatch_tree.context_stack,
1705 )
1706 }
1707
1708 pub fn bindings_for_action_in(
1709 &self,
1710 action: &dyn Action,
1711 focus_handle: &FocusHandle,
1712 ) -> Vec<KeyBinding> {
1713 let dispatch_tree = &self.window.rendered_frame.dispatch_tree;
1714
1715 let Some(node_id) = dispatch_tree.focusable_node_id(focus_handle.id) else {
1716 return vec![];
1717 };
1718 let context_stack = dispatch_tree
1719 .dispatch_path(node_id)
1720 .into_iter()
1721 .filter_map(|node_id| dispatch_tree.node(node_id).context.clone())
1722 .collect();
1723 dispatch_tree.bindings_for_action(action, &context_stack)
1724 }
1725
1726 pub fn listener_for<V: Render, E>(
1727 &self,
1728 view: &View<V>,
1729 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
1730 ) -> impl Fn(&E, &mut WindowContext) + 'static {
1731 let view = view.downgrade();
1732 move |e: &E, cx: &mut WindowContext| {
1733 view.update(cx, |view, cx| f(view, e, cx)).ok();
1734 }
1735 }
1736
1737 pub fn handler_for<V: Render>(
1738 &self,
1739 view: &View<V>,
1740 f: impl Fn(&mut V, &mut ViewContext<V>) + 'static,
1741 ) -> impl Fn(&mut WindowContext) {
1742 let view = view.downgrade();
1743 move |cx: &mut WindowContext| {
1744 view.update(cx, |view, cx| f(view, cx)).ok();
1745 }
1746 }
1747
1748 //========== ELEMENT RELATED FUNCTIONS ===========
1749 pub fn with_key_dispatch<R>(
1750 &mut self,
1751 context: Option<KeyContext>,
1752 focus_handle: Option<FocusHandle>,
1753 f: impl FnOnce(Option<FocusHandle>, &mut Self) -> R,
1754 ) -> R {
1755 let window = &mut self.window;
1756 window.next_frame.dispatch_tree.push_node(context.clone());
1757 if let Some(focus_handle) = focus_handle.as_ref() {
1758 window
1759 .next_frame
1760 .dispatch_tree
1761 .make_focusable(focus_handle.id);
1762 }
1763 let result = f(focus_handle, self);
1764
1765 self.window.next_frame.dispatch_tree.pop_node();
1766
1767 result
1768 }
1769
1770 /// Set an input handler, such as [ElementInputHandler], which interfaces with the
1771 /// platform to receive textual input with proper integration with concerns such
1772 /// as IME interactions.
1773 pub fn handle_input(
1774 &mut self,
1775 focus_handle: &FocusHandle,
1776 input_handler: impl PlatformInputHandler,
1777 ) {
1778 if focus_handle.is_focused(self) {
1779 self.window
1780 .platform_window
1781 .set_input_handler(Box::new(input_handler));
1782 }
1783 }
1784
1785 pub fn on_window_should_close(&mut self, f: impl Fn(&mut WindowContext) -> bool + 'static) {
1786 let mut this = self.to_async();
1787 self.window
1788 .platform_window
1789 .on_should_close(Box::new(move || this.update(|_, cx| f(cx)).unwrap_or(true)))
1790 }
1791}
1792
1793impl Context for WindowContext<'_> {
1794 type Result<T> = T;
1795
1796 fn build_model<T>(
1797 &mut self,
1798 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
1799 ) -> Model<T>
1800 where
1801 T: 'static,
1802 {
1803 let slot = self.app.entities.reserve();
1804 let model = build_model(&mut ModelContext::new(&mut *self.app, slot.downgrade()));
1805 self.entities.insert(slot, model)
1806 }
1807
1808 fn update_model<T: 'static, R>(
1809 &mut self,
1810 model: &Model<T>,
1811 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
1812 ) -> R {
1813 let mut entity = self.entities.lease(model);
1814 let result = update(
1815 &mut *entity,
1816 &mut ModelContext::new(&mut *self.app, model.downgrade()),
1817 );
1818 self.entities.end_lease(entity);
1819 result
1820 }
1821
1822 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
1823 where
1824 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
1825 {
1826 if window == self.window.handle {
1827 let root_view = self.window.root_view.clone().unwrap();
1828 Ok(update(root_view, self))
1829 } else {
1830 window.update(self.app, update)
1831 }
1832 }
1833
1834 fn read_model<T, R>(
1835 &self,
1836 handle: &Model<T>,
1837 read: impl FnOnce(&T, &AppContext) -> R,
1838 ) -> Self::Result<R>
1839 where
1840 T: 'static,
1841 {
1842 let entity = self.entities.read(handle);
1843 read(&*entity, &*self.app)
1844 }
1845
1846 fn read_window<T, R>(
1847 &self,
1848 window: &WindowHandle<T>,
1849 read: impl FnOnce(View<T>, &AppContext) -> R,
1850 ) -> Result<R>
1851 where
1852 T: 'static,
1853 {
1854 if window.any_handle == self.window.handle {
1855 let root_view = self
1856 .window
1857 .root_view
1858 .clone()
1859 .unwrap()
1860 .downcast::<T>()
1861 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
1862 Ok(read(root_view, self))
1863 } else {
1864 self.app.read_window(window, read)
1865 }
1866 }
1867}
1868
1869impl VisualContext for WindowContext<'_> {
1870 fn build_view<V>(
1871 &mut self,
1872 build_view_state: impl FnOnce(&mut ViewContext<'_, V>) -> V,
1873 ) -> Self::Result<View<V>>
1874 where
1875 V: 'static + Render,
1876 {
1877 let slot = self.app.entities.reserve();
1878 let view = View {
1879 model: slot.clone(),
1880 };
1881 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
1882 let entity = build_view_state(&mut cx);
1883 cx.entities.insert(slot, entity);
1884
1885 cx.new_view_observers
1886 .clone()
1887 .retain(&TypeId::of::<V>(), |observer| {
1888 let any_view = AnyView::from(view.clone());
1889 (observer)(any_view, self);
1890 true
1891 });
1892
1893 view
1894 }
1895
1896 /// Update the given view. Prefer calling `View::update` instead, which calls this method.
1897 fn update_view<T: 'static, R>(
1898 &mut self,
1899 view: &View<T>,
1900 update: impl FnOnce(&mut T, &mut ViewContext<'_, T>) -> R,
1901 ) -> Self::Result<R> {
1902 let mut lease = self.app.entities.lease(&view.model);
1903 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
1904 let result = update(&mut *lease, &mut cx);
1905 cx.app.entities.end_lease(lease);
1906 result
1907 }
1908
1909 fn replace_root_view<V>(
1910 &mut self,
1911 build_view: impl FnOnce(&mut ViewContext<'_, V>) -> V,
1912 ) -> Self::Result<View<V>>
1913 where
1914 V: 'static + Render,
1915 {
1916 let slot = self.app.entities.reserve();
1917 let view = View {
1918 model: slot.clone(),
1919 };
1920 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
1921 let entity = build_view(&mut cx);
1922 self.entities.insert(slot, entity);
1923 self.window.root_view = Some(view.clone().into());
1924 view
1925 }
1926
1927 fn focus_view<V: crate::FocusableView>(&mut self, view: &View<V>) -> Self::Result<()> {
1928 self.update_view(view, |view, cx| {
1929 view.focus_handle(cx).clone().focus(cx);
1930 })
1931 }
1932
1933 fn dismiss_view<V>(&mut self, view: &View<V>) -> Self::Result<()>
1934 where
1935 V: ManagedView,
1936 {
1937 self.update_view(view, |_, cx| cx.emit(DismissEvent))
1938 }
1939}
1940
1941impl<'a> std::ops::Deref for WindowContext<'a> {
1942 type Target = AppContext;
1943
1944 fn deref(&self) -> &Self::Target {
1945 &self.app
1946 }
1947}
1948
1949impl<'a> std::ops::DerefMut for WindowContext<'a> {
1950 fn deref_mut(&mut self) -> &mut Self::Target {
1951 &mut self.app
1952 }
1953}
1954
1955impl<'a> Borrow<AppContext> for WindowContext<'a> {
1956 fn borrow(&self) -> &AppContext {
1957 &self.app
1958 }
1959}
1960
1961impl<'a> BorrowMut<AppContext> for WindowContext<'a> {
1962 fn borrow_mut(&mut self) -> &mut AppContext {
1963 &mut self.app
1964 }
1965}
1966
1967pub trait BorrowWindow: BorrowMut<Window> + BorrowMut<AppContext> {
1968 fn app_mut(&mut self) -> &mut AppContext {
1969 self.borrow_mut()
1970 }
1971
1972 fn app(&self) -> &AppContext {
1973 self.borrow()
1974 }
1975
1976 fn window(&self) -> &Window {
1977 self.borrow()
1978 }
1979
1980 fn window_mut(&mut self) -> &mut Window {
1981 self.borrow_mut()
1982 }
1983
1984 /// Pushes the given element id onto the global stack and invokes the given closure
1985 /// with a `GlobalElementId`, which disambiguates the given id in the context of its ancestor
1986 /// ids. Because elements are discarded and recreated on each frame, the `GlobalElementId` is
1987 /// used to associate state with identified elements across separate frames.
1988 fn with_element_id<R>(
1989 &mut self,
1990 id: Option<impl Into<ElementId>>,
1991 f: impl FnOnce(&mut Self) -> R,
1992 ) -> R {
1993 if let Some(id) = id.map(Into::into) {
1994 let window = self.window_mut();
1995 window.element_id_stack.push(id.into());
1996 let result = f(self);
1997 let window: &mut Window = self.borrow_mut();
1998 window.element_id_stack.pop();
1999 result
2000 } else {
2001 f(self)
2002 }
2003 }
2004
2005 /// Invoke the given function with the given content mask after intersecting it
2006 /// with the current mask.
2007 fn with_content_mask<R>(
2008 &mut self,
2009 mask: Option<ContentMask<Pixels>>,
2010 f: impl FnOnce(&mut Self) -> R,
2011 ) -> R {
2012 if let Some(mask) = mask {
2013 let mask = mask.intersect(&self.content_mask());
2014 self.window_mut().next_frame.content_mask_stack.push(mask);
2015 let result = f(self);
2016 self.window_mut().next_frame.content_mask_stack.pop();
2017 result
2018 } else {
2019 f(self)
2020 }
2021 }
2022
2023 /// Invoke the given function with the content mask reset to that
2024 /// of the window.
2025 fn break_content_mask<R>(&mut self, f: impl FnOnce(&mut Self) -> R) -> R {
2026 let mask = ContentMask {
2027 bounds: Bounds {
2028 origin: Point::default(),
2029 size: self.window().viewport_size,
2030 },
2031 };
2032 self.window_mut().next_frame.content_mask_stack.push(mask);
2033 let result = f(self);
2034 self.window_mut().next_frame.content_mask_stack.pop();
2035 result
2036 }
2037
2038 /// Update the global element offset relative to the current offset. This is used to implement
2039 /// scrolling.
2040 fn with_element_offset<R>(
2041 &mut self,
2042 offset: Point<Pixels>,
2043 f: impl FnOnce(&mut Self) -> R,
2044 ) -> R {
2045 if offset.is_zero() {
2046 return f(self);
2047 };
2048
2049 let abs_offset = self.element_offset() + offset;
2050 self.with_absolute_element_offset(abs_offset, f)
2051 }
2052
2053 /// Update the global element offset based on the given offset. This is used to implement
2054 /// drag handles and other manual painting of elements.
2055 fn with_absolute_element_offset<R>(
2056 &mut self,
2057 offset: Point<Pixels>,
2058 f: impl FnOnce(&mut Self) -> R,
2059 ) -> R {
2060 self.window_mut()
2061 .next_frame
2062 .element_offset_stack
2063 .push(offset);
2064 let result = f(self);
2065 self.window_mut().next_frame.element_offset_stack.pop();
2066 result
2067 }
2068
2069 /// Obtain the current element offset.
2070 fn element_offset(&self) -> Point<Pixels> {
2071 self.window()
2072 .next_frame
2073 .element_offset_stack
2074 .last()
2075 .copied()
2076 .unwrap_or_default()
2077 }
2078
2079 /// Update or initialize state for an element with the given id that lives across multiple
2080 /// frames. If an element with this id existed in the rendered frame, its state will be passed
2081 /// to the given closure. The state returned by the closure will be stored so it can be referenced
2082 /// when drawing the next frame.
2083 fn with_element_state<S, R>(
2084 &mut self,
2085 id: ElementId,
2086 f: impl FnOnce(Option<S>, &mut Self) -> (R, S),
2087 ) -> R
2088 where
2089 S: 'static,
2090 {
2091 self.with_element_id(Some(id), |cx| {
2092 let global_id = cx.window().element_id_stack.clone();
2093
2094 if let Some(any) = cx
2095 .window_mut()
2096 .next_frame
2097 .element_states
2098 .remove(&global_id)
2099 .or_else(|| {
2100 cx.window_mut()
2101 .rendered_frame
2102 .element_states
2103 .remove(&global_id)
2104 })
2105 {
2106 let ElementStateBox {
2107 inner,
2108
2109 #[cfg(debug_assertions)]
2110 type_name
2111 } = any;
2112 // Using the extra inner option to avoid needing to reallocate a new box.
2113 let mut state_box = inner
2114 .downcast::<Option<S>>()
2115 .map_err(|_| {
2116 #[cfg(debug_assertions)]
2117 {
2118 anyhow!(
2119 "invalid element state type for id, requested_type {:?}, actual type: {:?}",
2120 std::any::type_name::<S>(),
2121 type_name
2122 )
2123 }
2124
2125 #[cfg(not(debug_assertions))]
2126 {
2127 anyhow!(
2128 "invalid element state type for id, requested_type {:?}",
2129 std::any::type_name::<S>(),
2130 )
2131 }
2132 })
2133 .unwrap();
2134
2135 // Actual: Option<AnyElement> <- View
2136 // Requested: () <- AnyElemet
2137 let state = state_box
2138 .take()
2139 .expect("element state is already on the stack");
2140 let (result, state) = f(Some(state), cx);
2141 state_box.replace(state);
2142 cx.window_mut()
2143 .next_frame
2144 .element_states
2145 .insert(global_id, ElementStateBox {
2146 inner: state_box,
2147
2148 #[cfg(debug_assertions)]
2149 type_name
2150 });
2151 result
2152 } else {
2153 let (result, state) = f(None, cx);
2154 cx.window_mut()
2155 .next_frame
2156 .element_states
2157 .insert(global_id,
2158 ElementStateBox {
2159 inner: Box::new(Some(state)),
2160
2161 #[cfg(debug_assertions)]
2162 type_name: std::any::type_name::<S>()
2163 }
2164
2165 );
2166 result
2167 }
2168 })
2169 }
2170
2171 /// Obtain the current content mask.
2172 fn content_mask(&self) -> ContentMask<Pixels> {
2173 self.window()
2174 .next_frame
2175 .content_mask_stack
2176 .last()
2177 .cloned()
2178 .unwrap_or_else(|| ContentMask {
2179 bounds: Bounds {
2180 origin: Point::default(),
2181 size: self.window().viewport_size,
2182 },
2183 })
2184 }
2185
2186 /// The size of an em for the base font of the application. Adjusting this value allows the
2187 /// UI to scale, just like zooming a web page.
2188 fn rem_size(&self) -> Pixels {
2189 self.window().rem_size
2190 }
2191}
2192
2193impl Borrow<Window> for WindowContext<'_> {
2194 fn borrow(&self) -> &Window {
2195 &self.window
2196 }
2197}
2198
2199impl BorrowMut<Window> for WindowContext<'_> {
2200 fn borrow_mut(&mut self) -> &mut Window {
2201 &mut self.window
2202 }
2203}
2204
2205impl<T> BorrowWindow for T where T: BorrowMut<AppContext> + BorrowMut<Window> {}
2206
2207pub struct ViewContext<'a, V> {
2208 window_cx: WindowContext<'a>,
2209 view: &'a View<V>,
2210}
2211
2212impl<V> Borrow<AppContext> for ViewContext<'_, V> {
2213 fn borrow(&self) -> &AppContext {
2214 &*self.window_cx.app
2215 }
2216}
2217
2218impl<V> BorrowMut<AppContext> for ViewContext<'_, V> {
2219 fn borrow_mut(&mut self) -> &mut AppContext {
2220 &mut *self.window_cx.app
2221 }
2222}
2223
2224impl<V> Borrow<Window> for ViewContext<'_, V> {
2225 fn borrow(&self) -> &Window {
2226 &*self.window_cx.window
2227 }
2228}
2229
2230impl<V> BorrowMut<Window> for ViewContext<'_, V> {
2231 fn borrow_mut(&mut self) -> &mut Window {
2232 &mut *self.window_cx.window
2233 }
2234}
2235
2236impl<'a, V: 'static> ViewContext<'a, V> {
2237 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window, view: &'a View<V>) -> Self {
2238 Self {
2239 window_cx: WindowContext::new(app, window),
2240 view,
2241 }
2242 }
2243
2244 pub fn entity_id(&self) -> EntityId {
2245 self.view.entity_id()
2246 }
2247
2248 pub fn view(&self) -> &View<V> {
2249 self.view
2250 }
2251
2252 pub fn model(&self) -> &Model<V> {
2253 &self.view.model
2254 }
2255
2256 /// Access the underlying window context.
2257 pub fn window_context(&mut self) -> &mut WindowContext<'a> {
2258 &mut self.window_cx
2259 }
2260
2261 pub fn with_z_index<R>(&mut self, z_index: u8, f: impl FnOnce(&mut Self) -> R) -> R {
2262 self.window.next_frame.z_index_stack.push(z_index);
2263 let result = f(self);
2264 self.window.next_frame.z_index_stack.pop();
2265 result
2266 }
2267
2268 pub fn on_next_frame(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static)
2269 where
2270 V: 'static,
2271 {
2272 let view = self.view().clone();
2273 self.window_cx.on_next_frame(move |cx| view.update(cx, f));
2274 }
2275
2276 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
2277 /// that are currently on the stack to be returned to the app.
2278 pub fn defer(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static) {
2279 let view = self.view().downgrade();
2280 self.window_cx.defer(move |cx| {
2281 view.update(cx, f).ok();
2282 });
2283 }
2284
2285 pub fn observe<V2, E>(
2286 &mut self,
2287 entity: &E,
2288 mut on_notify: impl FnMut(&mut V, E, &mut ViewContext<'_, V>) + 'static,
2289 ) -> Subscription
2290 where
2291 V2: 'static,
2292 V: 'static,
2293 E: Entity<V2>,
2294 {
2295 let view = self.view().downgrade();
2296 let entity_id = entity.entity_id();
2297 let entity = entity.downgrade();
2298 let window_handle = self.window.handle;
2299 let (subscription, activate) = self.app.observers.insert(
2300 entity_id,
2301 Box::new(move |cx| {
2302 window_handle
2303 .update(cx, |_, cx| {
2304 if let Some(handle) = E::upgrade_from(&entity) {
2305 view.update(cx, |this, cx| on_notify(this, handle, cx))
2306 .is_ok()
2307 } else {
2308 false
2309 }
2310 })
2311 .unwrap_or(false)
2312 }),
2313 );
2314 self.app.defer(move |_| activate());
2315 subscription
2316 }
2317
2318 pub fn subscribe<V2, E, Evt>(
2319 &mut self,
2320 entity: &E,
2321 mut on_event: impl FnMut(&mut V, E, &Evt, &mut ViewContext<'_, V>) + 'static,
2322 ) -> Subscription
2323 where
2324 V2: EventEmitter<Evt>,
2325 E: Entity<V2>,
2326 Evt: 'static,
2327 {
2328 let view = self.view().downgrade();
2329 let entity_id = entity.entity_id();
2330 let handle = entity.downgrade();
2331 let window_handle = self.window.handle;
2332 let (subscription, activate) = self.app.event_listeners.insert(
2333 entity_id,
2334 (
2335 TypeId::of::<Evt>(),
2336 Box::new(move |event, cx| {
2337 window_handle
2338 .update(cx, |_, cx| {
2339 if let Some(handle) = E::upgrade_from(&handle) {
2340 let event = event.downcast_ref().expect("invalid event type");
2341 view.update(cx, |this, cx| on_event(this, handle, event, cx))
2342 .is_ok()
2343 } else {
2344 false
2345 }
2346 })
2347 .unwrap_or(false)
2348 }),
2349 ),
2350 );
2351 self.app.defer(move |_| activate());
2352 subscription
2353 }
2354
2355 pub fn on_release(
2356 &mut self,
2357 on_release: impl FnOnce(&mut V, &mut WindowContext) + 'static,
2358 ) -> Subscription {
2359 let window_handle = self.window.handle;
2360 let (subscription, activate) = self.app.release_listeners.insert(
2361 self.view.model.entity_id,
2362 Box::new(move |this, cx| {
2363 let this = this.downcast_mut().expect("invalid entity type");
2364 let _ = window_handle.update(cx, |_, cx| on_release(this, cx));
2365 }),
2366 );
2367 activate();
2368 subscription
2369 }
2370
2371 pub fn observe_release<V2, E>(
2372 &mut self,
2373 entity: &E,
2374 mut on_release: impl FnMut(&mut V, &mut V2, &mut ViewContext<'_, V>) + 'static,
2375 ) -> Subscription
2376 where
2377 V: 'static,
2378 V2: 'static,
2379 E: Entity<V2>,
2380 {
2381 let view = self.view().downgrade();
2382 let entity_id = entity.entity_id();
2383 let window_handle = self.window.handle;
2384 let (subscription, activate) = self.app.release_listeners.insert(
2385 entity_id,
2386 Box::new(move |entity, cx| {
2387 let entity = entity.downcast_mut().expect("invalid entity type");
2388 let _ = window_handle.update(cx, |_, cx| {
2389 view.update(cx, |this, cx| on_release(this, entity, cx))
2390 });
2391 }),
2392 );
2393 activate();
2394 subscription
2395 }
2396
2397 pub fn notify(&mut self) {
2398 if !self.window.drawing {
2399 self.window_cx.notify();
2400 self.window_cx.app.push_effect(Effect::Notify {
2401 emitter: self.view.model.entity_id,
2402 });
2403 }
2404 }
2405
2406 pub fn observe_window_bounds(
2407 &mut self,
2408 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2409 ) -> Subscription {
2410 let view = self.view.downgrade();
2411 let (subscription, activate) = self.window.bounds_observers.insert(
2412 (),
2413 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
2414 );
2415 activate();
2416 subscription
2417 }
2418
2419 pub fn observe_window_activation(
2420 &mut self,
2421 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2422 ) -> Subscription {
2423 let view = self.view.downgrade();
2424 let (subscription, activate) = self.window.activation_observers.insert(
2425 (),
2426 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
2427 );
2428 activate();
2429 subscription
2430 }
2431
2432 /// Register a listener to be called when the given focus handle receives focus.
2433 /// Unlike [on_focus_changed], returns a subscription and persists until the subscription
2434 /// is dropped.
2435 pub fn on_focus(
2436 &mut self,
2437 handle: &FocusHandle,
2438 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2439 ) -> Subscription {
2440 let view = self.view.downgrade();
2441 let focus_id = handle.id;
2442 let (subscription, activate) = self.window.focus_listeners.insert(
2443 (),
2444 Box::new(move |event, cx| {
2445 view.update(cx, |view, cx| {
2446 if event.previous_focus_path.last() != Some(&focus_id)
2447 && event.current_focus_path.last() == Some(&focus_id)
2448 {
2449 listener(view, cx)
2450 }
2451 })
2452 .is_ok()
2453 }),
2454 );
2455 self.app.defer(move |_| activate());
2456 subscription
2457 }
2458
2459 /// Register a listener to be called when the given focus handle or one of its descendants receives focus.
2460 /// Unlike [on_focus_changed], returns a subscription and persists until the subscription
2461 /// is dropped.
2462 pub fn on_focus_in(
2463 &mut self,
2464 handle: &FocusHandle,
2465 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2466 ) -> Subscription {
2467 let view = self.view.downgrade();
2468 let focus_id = handle.id;
2469 let (subscription, activate) = self.window.focus_listeners.insert(
2470 (),
2471 Box::new(move |event, cx| {
2472 view.update(cx, |view, cx| {
2473 if !event.previous_focus_path.contains(&focus_id)
2474 && event.current_focus_path.contains(&focus_id)
2475 {
2476 listener(view, cx)
2477 }
2478 })
2479 .is_ok()
2480 }),
2481 );
2482 self.app.defer(move |_| activate());
2483 subscription
2484 }
2485
2486 /// Register a listener to be called when the given focus handle loses focus.
2487 /// Unlike [on_focus_changed], returns a subscription and persists until the subscription
2488 /// is dropped.
2489 pub fn on_blur(
2490 &mut self,
2491 handle: &FocusHandle,
2492 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2493 ) -> Subscription {
2494 let view = self.view.downgrade();
2495 let focus_id = handle.id;
2496 let (subscription, activate) = self.window.focus_listeners.insert(
2497 (),
2498 Box::new(move |event, cx| {
2499 view.update(cx, |view, cx| {
2500 if event.previous_focus_path.last() == Some(&focus_id)
2501 && event.current_focus_path.last() != Some(&focus_id)
2502 {
2503 listener(view, cx)
2504 }
2505 })
2506 .is_ok()
2507 }),
2508 );
2509 self.app.defer(move |_| activate());
2510 subscription
2511 }
2512
2513 /// Register a listener to be called when the window loses focus.
2514 /// Unlike [on_focus_changed], returns a subscription and persists until the subscription
2515 /// is dropped.
2516 pub fn on_blur_window(
2517 &mut self,
2518 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2519 ) -> Subscription {
2520 let view = self.view.downgrade();
2521 let (subscription, activate) = self.window.blur_listeners.insert(
2522 (),
2523 Box::new(move |cx| view.update(cx, |view, cx| listener(view, cx)).is_ok()),
2524 );
2525 activate();
2526 subscription
2527 }
2528
2529 /// Register a listener to be called when the given focus handle or one of its descendants loses focus.
2530 /// Unlike [on_focus_changed], returns a subscription and persists until the subscription
2531 /// is dropped.
2532 pub fn on_focus_out(
2533 &mut self,
2534 handle: &FocusHandle,
2535 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2536 ) -> Subscription {
2537 let view = self.view.downgrade();
2538 let focus_id = handle.id;
2539 let (subscription, activate) = self.window.focus_listeners.insert(
2540 (),
2541 Box::new(move |event, cx| {
2542 view.update(cx, |view, cx| {
2543 if event.previous_focus_path.contains(&focus_id)
2544 && !event.current_focus_path.contains(&focus_id)
2545 {
2546 listener(view, cx)
2547 }
2548 })
2549 .is_ok()
2550 }),
2551 );
2552 self.app.defer(move |_| activate());
2553 subscription
2554 }
2555
2556 pub fn spawn<Fut, R>(
2557 &mut self,
2558 f: impl FnOnce(WeakView<V>, AsyncWindowContext) -> Fut,
2559 ) -> Task<R>
2560 where
2561 R: 'static,
2562 Fut: Future<Output = R> + 'static,
2563 {
2564 let view = self.view().downgrade();
2565 self.window_cx.spawn(|cx| f(view, cx))
2566 }
2567
2568 pub fn update_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
2569 where
2570 G: 'static,
2571 {
2572 let mut global = self.app.lease_global::<G>();
2573 let result = f(&mut global, self);
2574 self.app.end_global_lease(global);
2575 result
2576 }
2577
2578 pub fn observe_global<G: 'static>(
2579 &mut self,
2580 mut f: impl FnMut(&mut V, &mut ViewContext<'_, V>) + 'static,
2581 ) -> Subscription {
2582 let window_handle = self.window.handle;
2583 let view = self.view().downgrade();
2584 let (subscription, activate) = self.global_observers.insert(
2585 TypeId::of::<G>(),
2586 Box::new(move |cx| {
2587 window_handle
2588 .update(cx, |_, cx| view.update(cx, |view, cx| f(view, cx)).is_ok())
2589 .unwrap_or(false)
2590 }),
2591 );
2592 self.app.defer(move |_| activate());
2593 subscription
2594 }
2595
2596 pub fn on_mouse_event<Event: 'static>(
2597 &mut self,
2598 handler: impl Fn(&mut V, &Event, DispatchPhase, &mut ViewContext<V>) + 'static,
2599 ) {
2600 let handle = self.view().clone();
2601 self.window_cx.on_mouse_event(move |event, phase, cx| {
2602 handle.update(cx, |view, cx| {
2603 handler(view, event, phase, cx);
2604 })
2605 });
2606 }
2607
2608 pub fn on_key_event<Event: 'static>(
2609 &mut self,
2610 handler: impl Fn(&mut V, &Event, DispatchPhase, &mut ViewContext<V>) + 'static,
2611 ) {
2612 let handle = self.view().clone();
2613 self.window_cx.on_key_event(move |event, phase, cx| {
2614 handle.update(cx, |view, cx| {
2615 handler(view, event, phase, cx);
2616 })
2617 });
2618 }
2619
2620 pub fn on_action(
2621 &mut self,
2622 action_type: TypeId,
2623 listener: impl Fn(&mut V, &dyn Any, DispatchPhase, &mut ViewContext<V>) + 'static,
2624 ) {
2625 let handle = self.view().clone();
2626 self.window_cx
2627 .on_action(action_type, move |action, phase, cx| {
2628 handle.update(cx, |view, cx| {
2629 listener(view, action, phase, cx);
2630 })
2631 });
2632 }
2633
2634 pub fn emit<Evt>(&mut self, event: Evt)
2635 where
2636 Evt: 'static,
2637 V: EventEmitter<Evt>,
2638 {
2639 let emitter = self.view.model.entity_id;
2640 self.app.push_effect(Effect::Emit {
2641 emitter,
2642 event_type: TypeId::of::<Evt>(),
2643 event: Box::new(event),
2644 });
2645 }
2646
2647 pub fn focus_self(&mut self)
2648 where
2649 V: FocusableView,
2650 {
2651 self.defer(|view, cx| view.focus_handle(cx).focus(cx))
2652 }
2653
2654 pub fn dismiss_self(&mut self)
2655 where
2656 V: ManagedView,
2657 {
2658 self.defer(|_, cx| cx.emit(DismissEvent))
2659 }
2660
2661 pub fn listener<E>(
2662 &self,
2663 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
2664 ) -> impl Fn(&E, &mut WindowContext) + 'static {
2665 let view = self.view().downgrade();
2666 move |e: &E, cx: &mut WindowContext| {
2667 view.update(cx, |view, cx| f(view, e, cx)).ok();
2668 }
2669 }
2670}
2671
2672impl<V> Context for ViewContext<'_, V> {
2673 type Result<U> = U;
2674
2675 fn build_model<T: 'static>(
2676 &mut self,
2677 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
2678 ) -> Model<T> {
2679 self.window_cx.build_model(build_model)
2680 }
2681
2682 fn update_model<T: 'static, R>(
2683 &mut self,
2684 model: &Model<T>,
2685 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
2686 ) -> R {
2687 self.window_cx.update_model(model, update)
2688 }
2689
2690 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
2691 where
2692 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
2693 {
2694 self.window_cx.update_window(window, update)
2695 }
2696
2697 fn read_model<T, R>(
2698 &self,
2699 handle: &Model<T>,
2700 read: impl FnOnce(&T, &AppContext) -> R,
2701 ) -> Self::Result<R>
2702 where
2703 T: 'static,
2704 {
2705 self.window_cx.read_model(handle, read)
2706 }
2707
2708 fn read_window<T, R>(
2709 &self,
2710 window: &WindowHandle<T>,
2711 read: impl FnOnce(View<T>, &AppContext) -> R,
2712 ) -> Result<R>
2713 where
2714 T: 'static,
2715 {
2716 self.window_cx.read_window(window, read)
2717 }
2718}
2719
2720impl<V: 'static> VisualContext for ViewContext<'_, V> {
2721 fn build_view<W: Render + 'static>(
2722 &mut self,
2723 build_view_state: impl FnOnce(&mut ViewContext<'_, W>) -> W,
2724 ) -> Self::Result<View<W>> {
2725 self.window_cx.build_view(build_view_state)
2726 }
2727
2728 fn update_view<V2: 'static, R>(
2729 &mut self,
2730 view: &View<V2>,
2731 update: impl FnOnce(&mut V2, &mut ViewContext<'_, V2>) -> R,
2732 ) -> Self::Result<R> {
2733 self.window_cx.update_view(view, update)
2734 }
2735
2736 fn replace_root_view<W>(
2737 &mut self,
2738 build_view: impl FnOnce(&mut ViewContext<'_, W>) -> W,
2739 ) -> Self::Result<View<W>>
2740 where
2741 W: 'static + Render,
2742 {
2743 self.window_cx.replace_root_view(build_view)
2744 }
2745
2746 fn focus_view<W: FocusableView>(&mut self, view: &View<W>) -> Self::Result<()> {
2747 self.window_cx.focus_view(view)
2748 }
2749
2750 fn dismiss_view<W: ManagedView>(&mut self, view: &View<W>) -> Self::Result<()> {
2751 self.window_cx.dismiss_view(view)
2752 }
2753}
2754
2755impl<'a, V> std::ops::Deref for ViewContext<'a, V> {
2756 type Target = WindowContext<'a>;
2757
2758 fn deref(&self) -> &Self::Target {
2759 &self.window_cx
2760 }
2761}
2762
2763impl<'a, V> std::ops::DerefMut for ViewContext<'a, V> {
2764 fn deref_mut(&mut self) -> &mut Self::Target {
2765 &mut self.window_cx
2766 }
2767}
2768
2769// #[derive(Clone, Copy, Eq, PartialEq, Hash)]
2770slotmap::new_key_type! { pub struct WindowId; }
2771
2772impl WindowId {
2773 pub fn as_u64(&self) -> u64 {
2774 self.0.as_ffi()
2775 }
2776}
2777
2778#[derive(Deref, DerefMut)]
2779pub struct WindowHandle<V> {
2780 #[deref]
2781 #[deref_mut]
2782 pub(crate) any_handle: AnyWindowHandle,
2783 state_type: PhantomData<V>,
2784}
2785
2786impl<V: 'static + Render> WindowHandle<V> {
2787 pub fn new(id: WindowId) -> Self {
2788 WindowHandle {
2789 any_handle: AnyWindowHandle {
2790 id,
2791 state_type: TypeId::of::<V>(),
2792 },
2793 state_type: PhantomData,
2794 }
2795 }
2796
2797 pub fn root<C>(&self, cx: &mut C) -> Result<View<V>>
2798 where
2799 C: Context,
2800 {
2801 Flatten::flatten(cx.update_window(self.any_handle, |root_view, _| {
2802 root_view
2803 .downcast::<V>()
2804 .map_err(|_| anyhow!("the type of the window's root view has changed"))
2805 }))
2806 }
2807
2808 pub fn update<C, R>(
2809 &self,
2810 cx: &mut C,
2811 update: impl FnOnce(&mut V, &mut ViewContext<'_, V>) -> R,
2812 ) -> Result<R>
2813 where
2814 C: Context,
2815 {
2816 cx.update_window(self.any_handle, |root_view, cx| {
2817 let view = root_view
2818 .downcast::<V>()
2819 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
2820 Ok(cx.update_view(&view, update))
2821 })?
2822 }
2823
2824 pub fn read<'a>(&self, cx: &'a AppContext) -> Result<&'a V> {
2825 let x = cx
2826 .windows
2827 .get(self.id)
2828 .and_then(|window| {
2829 window
2830 .as_ref()
2831 .and_then(|window| window.root_view.clone())
2832 .map(|root_view| root_view.downcast::<V>())
2833 })
2834 .ok_or_else(|| anyhow!("window not found"))?
2835 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
2836
2837 Ok(x.read(cx))
2838 }
2839
2840 pub fn read_with<C, R>(&self, cx: &C, read_with: impl FnOnce(&V, &AppContext) -> R) -> Result<R>
2841 where
2842 C: Context,
2843 {
2844 cx.read_window(self, |root_view, cx| read_with(root_view.read(cx), cx))
2845 }
2846
2847 pub fn root_view<C>(&self, cx: &C) -> Result<View<V>>
2848 where
2849 C: Context,
2850 {
2851 cx.read_window(self, |root_view, _cx| root_view.clone())
2852 }
2853
2854 pub fn is_active(&self, cx: &AppContext) -> Option<bool> {
2855 cx.windows
2856 .get(self.id)
2857 .and_then(|window| window.as_ref().map(|window| window.active))
2858 }
2859}
2860
2861impl<V> Copy for WindowHandle<V> {}
2862
2863impl<V> Clone for WindowHandle<V> {
2864 fn clone(&self) -> Self {
2865 WindowHandle {
2866 any_handle: self.any_handle,
2867 state_type: PhantomData,
2868 }
2869 }
2870}
2871
2872impl<V> PartialEq for WindowHandle<V> {
2873 fn eq(&self, other: &Self) -> bool {
2874 self.any_handle == other.any_handle
2875 }
2876}
2877
2878impl<V> Eq for WindowHandle<V> {}
2879
2880impl<V> Hash for WindowHandle<V> {
2881 fn hash<H: Hasher>(&self, state: &mut H) {
2882 self.any_handle.hash(state);
2883 }
2884}
2885
2886impl<V: 'static> Into<AnyWindowHandle> for WindowHandle<V> {
2887 fn into(self) -> AnyWindowHandle {
2888 self.any_handle
2889 }
2890}
2891
2892#[derive(Copy, Clone, PartialEq, Eq, Hash)]
2893pub struct AnyWindowHandle {
2894 pub(crate) id: WindowId,
2895 state_type: TypeId,
2896}
2897
2898impl AnyWindowHandle {
2899 pub fn window_id(&self) -> WindowId {
2900 self.id
2901 }
2902
2903 pub fn downcast<T: 'static>(&self) -> Option<WindowHandle<T>> {
2904 if TypeId::of::<T>() == self.state_type {
2905 Some(WindowHandle {
2906 any_handle: *self,
2907 state_type: PhantomData,
2908 })
2909 } else {
2910 None
2911 }
2912 }
2913
2914 pub fn update<C, R>(
2915 self,
2916 cx: &mut C,
2917 update: impl FnOnce(AnyView, &mut WindowContext<'_>) -> R,
2918 ) -> Result<R>
2919 where
2920 C: Context,
2921 {
2922 cx.update_window(self, update)
2923 }
2924
2925 pub fn read<T, C, R>(self, cx: &C, read: impl FnOnce(View<T>, &AppContext) -> R) -> Result<R>
2926 where
2927 C: Context,
2928 T: 'static,
2929 {
2930 let view = self
2931 .downcast::<T>()
2932 .context("the type of the window's root view has changed")?;
2933
2934 cx.read_window(&view, read)
2935 }
2936}
2937
2938// #[cfg(any(test, feature = "test-support"))]
2939// impl From<SmallVec<[u32; 16]>> for StackingOrder {
2940// fn from(small_vec: SmallVec<[u32; 16]>) -> Self {
2941// StackingOrder(small_vec)
2942// }
2943// }
2944
2945#[derive(Clone, Debug, Eq, PartialEq, Hash)]
2946pub enum ElementId {
2947 View(EntityId),
2948 Integer(usize),
2949 Name(SharedString),
2950 FocusHandle(FocusId),
2951 NamedInteger(SharedString, usize),
2952}
2953
2954impl ElementId {
2955 pub(crate) fn from_entity_id(entity_id: EntityId) -> Self {
2956 ElementId::View(entity_id)
2957 }
2958}
2959
2960impl TryInto<SharedString> for ElementId {
2961 type Error = anyhow::Error;
2962
2963 fn try_into(self) -> anyhow::Result<SharedString> {
2964 if let ElementId::Name(name) = self {
2965 Ok(name)
2966 } else {
2967 Err(anyhow!("element id is not string"))
2968 }
2969 }
2970}
2971
2972impl From<usize> for ElementId {
2973 fn from(id: usize) -> Self {
2974 ElementId::Integer(id)
2975 }
2976}
2977
2978impl From<i32> for ElementId {
2979 fn from(id: i32) -> Self {
2980 Self::Integer(id as usize)
2981 }
2982}
2983
2984impl From<SharedString> for ElementId {
2985 fn from(name: SharedString) -> Self {
2986 ElementId::Name(name)
2987 }
2988}
2989
2990impl From<&'static str> for ElementId {
2991 fn from(name: &'static str) -> Self {
2992 ElementId::Name(name.into())
2993 }
2994}
2995
2996impl<'a> From<&'a FocusHandle> for ElementId {
2997 fn from(handle: &'a FocusHandle) -> Self {
2998 ElementId::FocusHandle(handle.id)
2999 }
3000}
3001
3002impl From<(&'static str, EntityId)> for ElementId {
3003 fn from((name, id): (&'static str, EntityId)) -> Self {
3004 ElementId::NamedInteger(name.into(), id.as_u64() as usize)
3005 }
3006}
3007
3008impl From<(&'static str, usize)> for ElementId {
3009 fn from((name, id): (&'static str, usize)) -> Self {
3010 ElementId::NamedInteger(name.into(), id)
3011 }
3012}
3013
3014impl From<(&'static str, u64)> for ElementId {
3015 fn from((name, id): (&'static str, u64)) -> Self {
3016 ElementId::NamedInteger(name.into(), id as usize)
3017 }
3018}
3019
3020/// A rectangle, to be rendered on the screen by GPUI at the given position and size.
3021pub struct PaintQuad {
3022 bounds: Bounds<Pixels>,
3023 corner_radii: Corners<Pixels>,
3024 background: Hsla,
3025 border_widths: Edges<Pixels>,
3026 border_color: Hsla,
3027}
3028
3029impl PaintQuad {
3030 /// Set the corner radii of the quad.
3031 pub fn corner_radii(self, corner_radii: impl Into<Corners<Pixels>>) -> Self {
3032 PaintQuad {
3033 corner_radii: corner_radii.into(),
3034 ..self
3035 }
3036 }
3037
3038 /// Set the border widths of the quad.
3039 pub fn border_widths(self, border_widths: impl Into<Edges<Pixels>>) -> Self {
3040 PaintQuad {
3041 border_widths: border_widths.into(),
3042 ..self
3043 }
3044 }
3045
3046 /// Set the border color of the quad.
3047 pub fn border_color(self, border_color: impl Into<Hsla>) -> Self {
3048 PaintQuad {
3049 border_color: border_color.into(),
3050 ..self
3051 }
3052 }
3053
3054 /// Set the background color of the quad.
3055 pub fn background(self, background: impl Into<Hsla>) -> Self {
3056 PaintQuad {
3057 background: background.into(),
3058 ..self
3059 }
3060 }
3061}
3062
3063/// Create a quad with the given parameters.
3064pub fn quad(
3065 bounds: Bounds<Pixels>,
3066 corner_radii: impl Into<Corners<Pixels>>,
3067 background: impl Into<Hsla>,
3068 border_widths: impl Into<Edges<Pixels>>,
3069 border_color: impl Into<Hsla>,
3070) -> PaintQuad {
3071 PaintQuad {
3072 bounds,
3073 corner_radii: corner_radii.into(),
3074 background: background.into(),
3075 border_widths: border_widths.into(),
3076 border_color: border_color.into(),
3077 }
3078}
3079
3080/// Create a filled quad with the given bounds and background color.
3081pub fn fill(bounds: impl Into<Bounds<Pixels>>, background: impl Into<Hsla>) -> PaintQuad {
3082 PaintQuad {
3083 bounds: bounds.into(),
3084 corner_radii: (0.).into(),
3085 background: background.into(),
3086 border_widths: (0.).into(),
3087 border_color: transparent_black(),
3088 }
3089}
3090
3091/// Create a rectangle outline with the given bounds, border color, and a 1px border width
3092pub fn outline(bounds: impl Into<Bounds<Pixels>>, border_color: impl Into<Hsla>) -> PaintQuad {
3093 PaintQuad {
3094 bounds: bounds.into(),
3095 corner_radii: (0.).into(),
3096 background: transparent_black(),
3097 border_widths: (1.).into(),
3098 border_color: border_color.into(),
3099 }
3100}