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 set_window_edited(&mut self, edited: bool) {
777 self.window.platform_window.set_edited(edited);
778 }
779
780 pub fn display(&self) -> Option<Rc<dyn PlatformDisplay>> {
781 self.platform
782 .displays()
783 .into_iter()
784 .find(|display| display.id() == self.window.display_id)
785 }
786
787 pub fn show_character_palette(&self) {
788 self.window.platform_window.show_character_palette();
789 }
790
791 /// The scale factor of the display associated with the window. For example, it could
792 /// return 2.0 for a "retina" display, indicating that each logical pixel should actually
793 /// be rendered as two pixels on screen.
794 pub fn scale_factor(&self) -> f32 {
795 self.window.scale_factor
796 }
797
798 /// The size of an em for the base font of the application. Adjusting this value allows the
799 /// UI to scale, just like zooming a web page.
800 pub fn rem_size(&self) -> Pixels {
801 self.window.rem_size
802 }
803
804 /// Sets the size of an em for the base font of the application. Adjusting this value allows the
805 /// UI to scale, just like zooming a web page.
806 pub fn set_rem_size(&mut self, rem_size: impl Into<Pixels>) {
807 self.window.rem_size = rem_size.into();
808 }
809
810 /// The line height associated with the current text style.
811 pub fn line_height(&self) -> Pixels {
812 let rem_size = self.rem_size();
813 let text_style = self.text_style();
814 text_style
815 .line_height
816 .to_pixels(text_style.font_size.into(), rem_size)
817 }
818
819 /// Call to prevent the default action of an event. Currently only used to prevent
820 /// parent elements from becoming focused on mouse down.
821 pub fn prevent_default(&mut self) {
822 self.window.default_prevented = true;
823 }
824
825 /// Obtain whether default has been prevented for the event currently being dispatched.
826 pub fn default_prevented(&self) -> bool {
827 self.window.default_prevented
828 }
829
830 /// Register a mouse event listener on the window for the next frame. The type of event
831 /// is determined by the first parameter of the given listener. When the next frame is rendered
832 /// the listener will be cleared.
833 pub fn on_mouse_event<Event: 'static>(
834 &mut self,
835 mut handler: impl FnMut(&Event, DispatchPhase, &mut WindowContext) + 'static,
836 ) {
837 let order = self.window.next_frame.z_index_stack.clone();
838 let handler = self
839 .window
840 .frame_arena
841 .alloc(|| {
842 move |event: &dyn Any, phase: DispatchPhase, cx: &mut WindowContext<'_>| {
843 handler(event.downcast_ref().unwrap(), phase, cx)
844 }
845 })
846 .map(|handler| handler as _);
847 self.window
848 .next_frame
849 .mouse_listeners
850 .entry(TypeId::of::<Event>())
851 .or_default()
852 .push((order, handler))
853 }
854
855 /// Register a key event listener on the window for the next frame. The type of event
856 /// is determined by the first parameter of the given listener. When the next frame is rendered
857 /// the listener will be cleared.
858 ///
859 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
860 /// a specific need to register a global listener.
861 pub fn on_key_event<Event: 'static>(
862 &mut self,
863 listener: impl Fn(&Event, DispatchPhase, &mut WindowContext) + 'static,
864 ) {
865 let listener = self
866 .window
867 .frame_arena
868 .alloc(|| {
869 move |event: &dyn Any, phase, cx: &mut WindowContext<'_>| {
870 if let Some(event) = event.downcast_ref::<Event>() {
871 listener(event, phase, cx)
872 }
873 }
874 })
875 .map(|handler| handler as _);
876 self.window.next_frame.dispatch_tree.on_key_event(listener);
877 }
878
879 /// Register an action listener on the window for the next frame. The type of action
880 /// is determined by the first parameter of the given listener. When the next frame is rendered
881 /// the listener will be cleared.
882 ///
883 /// This is a fairly low-level method, so prefer using action handlers on elements unless you have
884 /// a specific need to register a global listener.
885 pub fn on_action(
886 &mut self,
887 action_type: TypeId,
888 listener: impl Fn(&dyn Any, DispatchPhase, &mut WindowContext) + 'static,
889 ) {
890 let listener = self
891 .window
892 .frame_arena
893 .alloc(|| listener)
894 .map(|handler| handler as _);
895 self.window
896 .next_frame
897 .dispatch_tree
898 .on_action(action_type, listener);
899 }
900
901 pub fn is_action_available(&self, action: &dyn Action) -> bool {
902 let target = self
903 .focused()
904 .and_then(|focused_handle| {
905 self.window
906 .rendered_frame
907 .dispatch_tree
908 .focusable_node_id(focused_handle.id)
909 })
910 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
911 self.window
912 .rendered_frame
913 .dispatch_tree
914 .is_action_available(action, target)
915 }
916
917 /// The position of the mouse relative to the window.
918 pub fn mouse_position(&self) -> Point<Pixels> {
919 self.window.mouse_position
920 }
921
922 /// The current state of the keyboard's modifiers
923 pub fn modifiers(&self) -> Modifiers {
924 self.window.modifiers
925 }
926
927 pub fn set_cursor_style(&mut self, style: CursorStyle) {
928 self.window.requested_cursor_style = Some(style)
929 }
930
931 /// Called during painting to invoke the given closure in a new stacking context. The given
932 /// z-index is interpreted relative to the previous call to `stack`.
933 pub fn with_z_index<R>(&mut self, z_index: u8, f: impl FnOnce(&mut Self) -> R) -> R {
934 self.window.next_frame.z_index_stack.push(z_index);
935 let result = f(self);
936 self.window.next_frame.z_index_stack.pop();
937 result
938 }
939
940 /// Called during painting to track which z-index is on top at each pixel position
941 pub fn add_opaque_layer(&mut self, bounds: Bounds<Pixels>) {
942 let stacking_order = self.window.next_frame.z_index_stack.clone();
943 let depth_map = &mut self.window.next_frame.depth_map;
944 match depth_map.binary_search_by(|(level, _)| stacking_order.cmp(&level)) {
945 Ok(i) | Err(i) => depth_map.insert(i, (stacking_order, bounds)),
946 }
947 }
948
949 /// Returns true if there is no opaque layer containing the given point
950 /// on top of the given level. Layers whose level is an extension of the
951 /// level are not considered to be on top of the level.
952 pub fn was_top_layer(&self, point: &Point<Pixels>, level: &StackingOrder) -> bool {
953 for (opaque_level, bounds) in self.window.rendered_frame.depth_map.iter() {
954 if level >= opaque_level {
955 break;
956 }
957
958 if bounds.contains(point) && !opaque_level.starts_with(level) {
959 return false;
960 }
961 }
962 true
963 }
964
965 pub fn was_top_layer_under_active_drag(
966 &self,
967 point: &Point<Pixels>,
968 level: &StackingOrder,
969 ) -> bool {
970 for (opaque_level, bounds) in self.window.rendered_frame.depth_map.iter() {
971 if level >= opaque_level {
972 break;
973 }
974 if opaque_level.starts_with(&[ACTIVE_DRAG_Z_INDEX]) {
975 continue;
976 }
977
978 if bounds.contains(point) && !opaque_level.starts_with(level) {
979 return false;
980 }
981 }
982 true
983 }
984
985 /// Called during painting to get the current stacking order.
986 pub fn stacking_order(&self) -> &StackingOrder {
987 &self.window.next_frame.z_index_stack
988 }
989
990 /// Paint one or more drop shadows into the scene for the next frame at the current z-index.
991 pub fn paint_shadows(
992 &mut self,
993 bounds: Bounds<Pixels>,
994 corner_radii: Corners<Pixels>,
995 shadows: &[BoxShadow],
996 ) {
997 let scale_factor = self.scale_factor();
998 let content_mask = self.content_mask();
999 let window = &mut *self.window;
1000 for shadow in shadows {
1001 let mut shadow_bounds = bounds;
1002 shadow_bounds.origin += shadow.offset;
1003 shadow_bounds.dilate(shadow.spread_radius);
1004 window.next_frame.scene_builder.insert(
1005 &window.next_frame.z_index_stack,
1006 Shadow {
1007 order: 0,
1008 bounds: shadow_bounds.scale(scale_factor),
1009 content_mask: content_mask.scale(scale_factor),
1010 corner_radii: corner_radii.scale(scale_factor),
1011 color: shadow.color,
1012 blur_radius: shadow.blur_radius.scale(scale_factor),
1013 },
1014 );
1015 }
1016 }
1017
1018 /// Paint one or more quads into the scene for the next frame at the current stacking context.
1019 /// Quads are colored rectangular regions with an optional background, border, and corner radius.
1020 /// see [`fill`], [`outline`], and [`quad`] to construct this type.
1021 pub fn paint_quad(&mut self, quad: PaintQuad) {
1022 let scale_factor = self.scale_factor();
1023 let content_mask = self.content_mask();
1024
1025 let window = &mut *self.window;
1026 window.next_frame.scene_builder.insert(
1027 &window.next_frame.z_index_stack,
1028 Quad {
1029 order: 0,
1030 bounds: quad.bounds.scale(scale_factor),
1031 content_mask: content_mask.scale(scale_factor),
1032 background: quad.background,
1033 border_color: quad.border_color,
1034 corner_radii: quad.corner_radii.scale(scale_factor),
1035 border_widths: quad.border_widths.scale(scale_factor),
1036 },
1037 );
1038 }
1039
1040 /// Paint the given `Path` into the scene for the next frame at the current z-index.
1041 pub fn paint_path(&mut self, mut path: Path<Pixels>, color: impl Into<Hsla>) {
1042 let scale_factor = self.scale_factor();
1043 let content_mask = self.content_mask();
1044 path.content_mask = content_mask;
1045 path.color = color.into();
1046 let window = &mut *self.window;
1047 window
1048 .next_frame
1049 .scene_builder
1050 .insert(&window.next_frame.z_index_stack, path.scale(scale_factor));
1051 }
1052
1053 /// Paint an underline into the scene for the next frame at the current z-index.
1054 pub fn paint_underline(
1055 &mut self,
1056 origin: Point<Pixels>,
1057 width: Pixels,
1058 style: &UnderlineStyle,
1059 ) {
1060 let scale_factor = self.scale_factor();
1061 let height = if style.wavy {
1062 style.thickness * 3.
1063 } else {
1064 style.thickness
1065 };
1066 let bounds = Bounds {
1067 origin,
1068 size: size(width, height),
1069 };
1070 let content_mask = self.content_mask();
1071 let window = &mut *self.window;
1072 window.next_frame.scene_builder.insert(
1073 &window.next_frame.z_index_stack,
1074 Underline {
1075 order: 0,
1076 bounds: bounds.scale(scale_factor),
1077 content_mask: content_mask.scale(scale_factor),
1078 thickness: style.thickness.scale(scale_factor),
1079 color: style.color.unwrap_or_default(),
1080 wavy: style.wavy,
1081 },
1082 );
1083 }
1084
1085 /// Paint a monochrome (non-emoji) glyph into the scene for the next frame at the current z-index.
1086 /// The y component of the origin is the baseline of the glyph.
1087 pub fn paint_glyph(
1088 &mut self,
1089 origin: Point<Pixels>,
1090 font_id: FontId,
1091 glyph_id: GlyphId,
1092 font_size: Pixels,
1093 color: Hsla,
1094 ) -> Result<()> {
1095 let scale_factor = self.scale_factor();
1096 let glyph_origin = origin.scale(scale_factor);
1097 let subpixel_variant = Point {
1098 x: (glyph_origin.x.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
1099 y: (glyph_origin.y.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
1100 };
1101 let params = RenderGlyphParams {
1102 font_id,
1103 glyph_id,
1104 font_size,
1105 subpixel_variant,
1106 scale_factor,
1107 is_emoji: false,
1108 };
1109
1110 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
1111 if !raster_bounds.is_zero() {
1112 let tile =
1113 self.window
1114 .sprite_atlas
1115 .get_or_insert_with(¶ms.clone().into(), &mut || {
1116 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
1117 Ok((size, Cow::Owned(bytes)))
1118 })?;
1119 let bounds = Bounds {
1120 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
1121 size: tile.bounds.size.map(Into::into),
1122 };
1123 let content_mask = self.content_mask().scale(scale_factor);
1124 let window = &mut *self.window;
1125 window.next_frame.scene_builder.insert(
1126 &window.next_frame.z_index_stack,
1127 MonochromeSprite {
1128 order: 0,
1129 bounds,
1130 content_mask,
1131 color,
1132 tile,
1133 },
1134 );
1135 }
1136 Ok(())
1137 }
1138
1139 /// Paint an emoji glyph into the scene for the next frame at the current z-index.
1140 /// The y component of the origin is the baseline of the glyph.
1141 pub fn paint_emoji(
1142 &mut self,
1143 origin: Point<Pixels>,
1144 font_id: FontId,
1145 glyph_id: GlyphId,
1146 font_size: Pixels,
1147 ) -> Result<()> {
1148 let scale_factor = self.scale_factor();
1149 let glyph_origin = origin.scale(scale_factor);
1150 let params = RenderGlyphParams {
1151 font_id,
1152 glyph_id,
1153 font_size,
1154 // We don't render emojis with subpixel variants.
1155 subpixel_variant: Default::default(),
1156 scale_factor,
1157 is_emoji: true,
1158 };
1159
1160 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
1161 if !raster_bounds.is_zero() {
1162 let tile =
1163 self.window
1164 .sprite_atlas
1165 .get_or_insert_with(¶ms.clone().into(), &mut || {
1166 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
1167 Ok((size, Cow::Owned(bytes)))
1168 })?;
1169 let bounds = Bounds {
1170 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
1171 size: tile.bounds.size.map(Into::into),
1172 };
1173 let content_mask = self.content_mask().scale(scale_factor);
1174 let window = &mut *self.window;
1175
1176 window.next_frame.scene_builder.insert(
1177 &window.next_frame.z_index_stack,
1178 PolychromeSprite {
1179 order: 0,
1180 bounds,
1181 corner_radii: Default::default(),
1182 content_mask,
1183 tile,
1184 grayscale: false,
1185 },
1186 );
1187 }
1188 Ok(())
1189 }
1190
1191 /// Paint a monochrome SVG into the scene for the next frame at the current stacking context.
1192 pub fn paint_svg(
1193 &mut self,
1194 bounds: Bounds<Pixels>,
1195 path: SharedString,
1196 color: Hsla,
1197 ) -> Result<()> {
1198 let scale_factor = self.scale_factor();
1199 let bounds = bounds.scale(scale_factor);
1200 // Render the SVG at twice the size to get a higher quality result.
1201 let params = RenderSvgParams {
1202 path,
1203 size: bounds
1204 .size
1205 .map(|pixels| DevicePixels::from((pixels.0 * 2.).ceil() as i32)),
1206 };
1207
1208 let tile =
1209 self.window
1210 .sprite_atlas
1211 .get_or_insert_with(¶ms.clone().into(), &mut || {
1212 let bytes = self.svg_renderer.render(¶ms)?;
1213 Ok((params.size, Cow::Owned(bytes)))
1214 })?;
1215 let content_mask = self.content_mask().scale(scale_factor);
1216
1217 let window = &mut *self.window;
1218 window.next_frame.scene_builder.insert(
1219 &window.next_frame.z_index_stack,
1220 MonochromeSprite {
1221 order: 0,
1222 bounds,
1223 content_mask,
1224 color,
1225 tile,
1226 },
1227 );
1228
1229 Ok(())
1230 }
1231
1232 /// Paint an image into the scene for the next frame at the current z-index.
1233 pub fn paint_image(
1234 &mut self,
1235 bounds: Bounds<Pixels>,
1236 corner_radii: Corners<Pixels>,
1237 data: Arc<ImageData>,
1238 grayscale: bool,
1239 ) -> Result<()> {
1240 let scale_factor = self.scale_factor();
1241 let bounds = bounds.scale(scale_factor);
1242 let params = RenderImageParams { image_id: data.id };
1243
1244 let tile = self
1245 .window
1246 .sprite_atlas
1247 .get_or_insert_with(¶ms.clone().into(), &mut || {
1248 Ok((data.size(), Cow::Borrowed(data.as_bytes())))
1249 })?;
1250 let content_mask = self.content_mask().scale(scale_factor);
1251 let corner_radii = corner_radii.scale(scale_factor);
1252
1253 let window = &mut *self.window;
1254 window.next_frame.scene_builder.insert(
1255 &window.next_frame.z_index_stack,
1256 PolychromeSprite {
1257 order: 0,
1258 bounds,
1259 content_mask,
1260 corner_radii,
1261 tile,
1262 grayscale,
1263 },
1264 );
1265 Ok(())
1266 }
1267
1268 /// Paint a surface into the scene for the next frame at the current z-index.
1269 pub fn paint_surface(&mut self, bounds: Bounds<Pixels>, image_buffer: CVImageBuffer) {
1270 let scale_factor = self.scale_factor();
1271 let bounds = bounds.scale(scale_factor);
1272 let content_mask = self.content_mask().scale(scale_factor);
1273 let window = &mut *self.window;
1274 window.next_frame.scene_builder.insert(
1275 &window.next_frame.z_index_stack,
1276 Surface {
1277 order: 0,
1278 bounds,
1279 content_mask,
1280 image_buffer,
1281 },
1282 );
1283 }
1284
1285 /// Draw pixels to the display for this window based on the contents of its scene.
1286 pub(crate) fn draw(&mut self) -> Scene {
1287 self.window.dirty = false;
1288 self.window.drawing = true;
1289
1290 #[cfg(any(test, feature = "test-support"))]
1291 {
1292 self.window.focus_invalidated = false;
1293 }
1294
1295 self.text_system().start_frame();
1296 self.window.platform_window.clear_input_handler();
1297 self.window.layout_engine.as_mut().unwrap().clear();
1298 self.window.next_frame.clear();
1299 self.window.frame_arena.clear();
1300 let root_view = self.window.root_view.take().unwrap();
1301
1302 self.with_z_index(0, |cx| {
1303 cx.with_key_dispatch(Some(KeyContext::default()), None, |_, cx| {
1304 for (action_type, action_listeners) in &cx.app.global_action_listeners {
1305 for action_listener in action_listeners.iter().cloned() {
1306 let listener = cx
1307 .window
1308 .frame_arena
1309 .alloc(|| {
1310 move |action: &dyn Any, phase, cx: &mut WindowContext<'_>| {
1311 action_listener(action, phase, cx)
1312 }
1313 })
1314 .map(|listener| listener as _);
1315 cx.window
1316 .next_frame
1317 .dispatch_tree
1318 .on_action(*action_type, listener)
1319 }
1320 }
1321
1322 let available_space = cx.window.viewport_size.map(Into::into);
1323 root_view.draw(Point::default(), available_space, cx);
1324 })
1325 });
1326
1327 if let Some(active_drag) = self.app.active_drag.take() {
1328 self.with_z_index(ACTIVE_DRAG_Z_INDEX, |cx| {
1329 let offset = cx.mouse_position() - active_drag.cursor_offset;
1330 let available_space = size(AvailableSpace::MinContent, AvailableSpace::MinContent);
1331 active_drag.view.draw(offset, available_space, cx);
1332 });
1333 self.active_drag = Some(active_drag);
1334 } else if let Some(active_tooltip) = self.app.active_tooltip.take() {
1335 self.with_z_index(1, |cx| {
1336 let available_space = size(AvailableSpace::MinContent, AvailableSpace::MinContent);
1337 active_tooltip
1338 .view
1339 .draw(active_tooltip.cursor_offset, available_space, cx);
1340 });
1341 }
1342
1343 self.window
1344 .next_frame
1345 .dispatch_tree
1346 .preserve_pending_keystrokes(
1347 &mut self.window.rendered_frame.dispatch_tree,
1348 self.window.focus,
1349 );
1350 self.window.next_frame.focus = self.window.focus;
1351 self.window.root_view = Some(root_view);
1352
1353 let previous_focus_path = self.window.rendered_frame.focus_path();
1354 mem::swap(&mut self.window.rendered_frame, &mut self.window.next_frame);
1355 let current_focus_path = self.window.rendered_frame.focus_path();
1356
1357 if previous_focus_path != current_focus_path {
1358 if !previous_focus_path.is_empty() && current_focus_path.is_empty() {
1359 self.window
1360 .blur_listeners
1361 .clone()
1362 .retain(&(), |listener| listener(self));
1363 }
1364
1365 let event = FocusEvent {
1366 previous_focus_path,
1367 current_focus_path,
1368 };
1369 self.window
1370 .focus_listeners
1371 .clone()
1372 .retain(&(), |listener| listener(&event, self));
1373 }
1374
1375 let scene = self.window.rendered_frame.scene_builder.build();
1376
1377 // Set the cursor only if we're the active window.
1378 let cursor_style = self
1379 .window
1380 .requested_cursor_style
1381 .take()
1382 .unwrap_or(CursorStyle::Arrow);
1383 if self.is_window_active() {
1384 self.platform.set_cursor_style(cursor_style);
1385 }
1386
1387 self.window.drawing = false;
1388 ELEMENT_ARENA.with_borrow_mut(|element_arena| element_arena.clear());
1389
1390 scene
1391 }
1392
1393 /// Dispatch a mouse or keyboard event on the window.
1394 pub fn dispatch_event(&mut self, event: InputEvent) -> bool {
1395 // Handlers may set this to false by calling `stop_propagation`.
1396 self.app.propagate_event = true;
1397 // Handlers may set this to true by calling `prevent_default`.
1398 self.window.default_prevented = false;
1399
1400 let event = match event {
1401 // Track the mouse position with our own state, since accessing the platform
1402 // API for the mouse position can only occur on the main thread.
1403 InputEvent::MouseMove(mouse_move) => {
1404 self.window.mouse_position = mouse_move.position;
1405 self.window.modifiers = mouse_move.modifiers;
1406 InputEvent::MouseMove(mouse_move)
1407 }
1408 InputEvent::MouseDown(mouse_down) => {
1409 self.window.mouse_position = mouse_down.position;
1410 self.window.modifiers = mouse_down.modifiers;
1411 InputEvent::MouseDown(mouse_down)
1412 }
1413 InputEvent::MouseUp(mouse_up) => {
1414 self.window.mouse_position = mouse_up.position;
1415 self.window.modifiers = mouse_up.modifiers;
1416 InputEvent::MouseUp(mouse_up)
1417 }
1418 InputEvent::MouseExited(mouse_exited) => {
1419 // todo!("Should we record that the mouse is outside of the window somehow? Or are these global pixels?")
1420 self.window.modifiers = mouse_exited.modifiers;
1421
1422 InputEvent::MouseExited(mouse_exited)
1423 }
1424 InputEvent::ModifiersChanged(modifiers_changed) => {
1425 self.window.modifiers = modifiers_changed.modifiers;
1426 InputEvent::ModifiersChanged(modifiers_changed)
1427 }
1428 InputEvent::ScrollWheel(scroll_wheel) => {
1429 self.window.mouse_position = scroll_wheel.position;
1430 self.window.modifiers = scroll_wheel.modifiers;
1431 InputEvent::ScrollWheel(scroll_wheel)
1432 }
1433 // Translate dragging and dropping of external files from the operating system
1434 // to internal drag and drop events.
1435 InputEvent::FileDrop(file_drop) => match file_drop {
1436 FileDropEvent::Entered { position, files } => {
1437 self.window.mouse_position = position;
1438 if self.active_drag.is_none() {
1439 self.active_drag = Some(AnyDrag {
1440 value: Box::new(files.clone()),
1441 view: self.build_view(|_| files).into(),
1442 cursor_offset: position,
1443 });
1444 }
1445 InputEvent::MouseMove(MouseMoveEvent {
1446 position,
1447 pressed_button: Some(MouseButton::Left),
1448 modifiers: Modifiers::default(),
1449 })
1450 }
1451 FileDropEvent::Pending { position } => {
1452 self.window.mouse_position = position;
1453 InputEvent::MouseMove(MouseMoveEvent {
1454 position,
1455 pressed_button: Some(MouseButton::Left),
1456 modifiers: Modifiers::default(),
1457 })
1458 }
1459 FileDropEvent::Submit { position } => {
1460 self.activate(true);
1461 self.window.mouse_position = position;
1462 InputEvent::MouseUp(MouseUpEvent {
1463 button: MouseButton::Left,
1464 position,
1465 modifiers: Modifiers::default(),
1466 click_count: 1,
1467 })
1468 }
1469 FileDropEvent::Exited => InputEvent::MouseUp(MouseUpEvent {
1470 button: MouseButton::Left,
1471 position: Point::default(),
1472 modifiers: Modifiers::default(),
1473 click_count: 1,
1474 }),
1475 },
1476 InputEvent::KeyDown(_) | InputEvent::KeyUp(_) => event,
1477 };
1478
1479 if let Some(any_mouse_event) = event.mouse_event() {
1480 self.dispatch_mouse_event(any_mouse_event);
1481 } else if let Some(any_key_event) = event.keyboard_event() {
1482 self.dispatch_key_event(any_key_event);
1483 }
1484
1485 !self.app.propagate_event
1486 }
1487
1488 fn dispatch_mouse_event(&mut self, event: &dyn Any) {
1489 if let Some(mut handlers) = self
1490 .window
1491 .rendered_frame
1492 .mouse_listeners
1493 .remove(&event.type_id())
1494 {
1495 // Because handlers may add other handlers, we sort every time.
1496 handlers.sort_by(|(a, _), (b, _)| a.cmp(b));
1497
1498 // Capture phase, events bubble from back to front. Handlers for this phase are used for
1499 // special purposes, such as detecting events outside of a given Bounds.
1500 for (_, handler) in &mut handlers {
1501 handler(event, DispatchPhase::Capture, self);
1502 if !self.app.propagate_event {
1503 break;
1504 }
1505 }
1506
1507 // Bubble phase, where most normal handlers do their work.
1508 if self.app.propagate_event {
1509 for (_, handler) in handlers.iter_mut().rev() {
1510 handler(event, DispatchPhase::Bubble, self);
1511 if !self.app.propagate_event {
1512 break;
1513 }
1514 }
1515 }
1516
1517 if self.app.propagate_event && event.downcast_ref::<MouseUpEvent>().is_some() {
1518 self.active_drag = None;
1519 }
1520
1521 self.window
1522 .rendered_frame
1523 .mouse_listeners
1524 .insert(event.type_id(), handlers);
1525 }
1526 }
1527
1528 fn dispatch_key_event(&mut self, event: &dyn Any) {
1529 let node_id = self
1530 .window
1531 .focus
1532 .and_then(|focus_id| {
1533 self.window
1534 .rendered_frame
1535 .dispatch_tree
1536 .focusable_node_id(focus_id)
1537 })
1538 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
1539
1540 let dispatch_path = self
1541 .window
1542 .rendered_frame
1543 .dispatch_tree
1544 .dispatch_path(node_id);
1545
1546 let mut actions: Vec<Box<dyn Action>> = Vec::new();
1547
1548 // Capture phase
1549 let mut context_stack: SmallVec<[KeyContext; 16]> = SmallVec::new();
1550 self.propagate_event = true;
1551
1552 for node_id in &dispatch_path {
1553 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1554
1555 if let Some(context) = node.context.clone() {
1556 context_stack.push(context);
1557 }
1558
1559 for key_listener in node.key_listeners.clone() {
1560 key_listener(event, DispatchPhase::Capture, self);
1561 if !self.propagate_event {
1562 return;
1563 }
1564 }
1565 }
1566
1567 // Bubble phase
1568 for node_id in dispatch_path.iter().rev() {
1569 // Handle low level key events
1570 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1571 for key_listener in node.key_listeners.clone() {
1572 key_listener(event, DispatchPhase::Bubble, self);
1573 if !self.propagate_event {
1574 return;
1575 }
1576 }
1577
1578 // Match keystrokes
1579 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1580 if node.context.is_some() {
1581 if let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() {
1582 let mut new_actions = self
1583 .window
1584 .rendered_frame
1585 .dispatch_tree
1586 .dispatch_key(&key_down_event.keystroke, &context_stack);
1587 actions.append(&mut new_actions);
1588 }
1589
1590 context_stack.pop();
1591 }
1592 }
1593
1594 for action in actions {
1595 self.dispatch_action_on_node(node_id, action.boxed_clone());
1596 if !self.propagate_event {
1597 self.dispatch_keystroke_observers(event, Some(action));
1598 return;
1599 }
1600 }
1601 self.dispatch_keystroke_observers(event, None);
1602 }
1603
1604 pub fn has_pending_keystrokes(&self) -> bool {
1605 self.window
1606 .rendered_frame
1607 .dispatch_tree
1608 .has_pending_keystrokes()
1609 }
1610
1611 fn dispatch_action_on_node(&mut self, node_id: DispatchNodeId, action: Box<dyn Action>) {
1612 let dispatch_path = self
1613 .window
1614 .rendered_frame
1615 .dispatch_tree
1616 .dispatch_path(node_id);
1617
1618 // Capture phase
1619 for node_id in &dispatch_path {
1620 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1621 for DispatchActionListener {
1622 action_type,
1623 listener,
1624 } in node.action_listeners.clone()
1625 {
1626 let any_action = action.as_any();
1627 if action_type == any_action.type_id() {
1628 listener(any_action, DispatchPhase::Capture, self);
1629 if !self.propagate_event {
1630 return;
1631 }
1632 }
1633 }
1634 }
1635 // Bubble phase
1636 for node_id in dispatch_path.iter().rev() {
1637 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1638 for DispatchActionListener {
1639 action_type,
1640 listener,
1641 } in node.action_listeners.clone()
1642 {
1643 let any_action = action.as_any();
1644 if action_type == any_action.type_id() {
1645 self.propagate_event = false; // Actions stop propagation by default during the bubble phase
1646 listener(any_action, DispatchPhase::Bubble, self);
1647 if !self.propagate_event {
1648 return;
1649 }
1650 }
1651 }
1652 }
1653 }
1654
1655 /// Register the given handler to be invoked whenever the global of the given type
1656 /// is updated.
1657 pub fn observe_global<G: 'static>(
1658 &mut self,
1659 f: impl Fn(&mut WindowContext<'_>) + 'static,
1660 ) -> Subscription {
1661 let window_handle = self.window.handle;
1662 let (subscription, activate) = self.global_observers.insert(
1663 TypeId::of::<G>(),
1664 Box::new(move |cx| window_handle.update(cx, |_, cx| f(cx)).is_ok()),
1665 );
1666 self.app.defer(move |_| activate());
1667 subscription
1668 }
1669
1670 pub fn activate_window(&self) {
1671 self.window.platform_window.activate();
1672 }
1673
1674 pub fn minimize_window(&self) {
1675 self.window.platform_window.minimize();
1676 }
1677
1678 pub fn toggle_full_screen(&self) {
1679 self.window.platform_window.toggle_full_screen();
1680 }
1681
1682 pub fn prompt(
1683 &self,
1684 level: PromptLevel,
1685 msg: &str,
1686 answers: &[&str],
1687 ) -> oneshot::Receiver<usize> {
1688 self.window.platform_window.prompt(level, msg, answers)
1689 }
1690
1691 pub fn available_actions(&self) -> Vec<Box<dyn Action>> {
1692 let node_id = self
1693 .window
1694 .focus
1695 .and_then(|focus_id| {
1696 self.window
1697 .rendered_frame
1698 .dispatch_tree
1699 .focusable_node_id(focus_id)
1700 })
1701 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
1702
1703 self.window
1704 .rendered_frame
1705 .dispatch_tree
1706 .available_actions(node_id)
1707 }
1708
1709 pub fn bindings_for_action(&self, action: &dyn Action) -> Vec<KeyBinding> {
1710 self.window
1711 .rendered_frame
1712 .dispatch_tree
1713 .bindings_for_action(
1714 action,
1715 &self.window.rendered_frame.dispatch_tree.context_stack,
1716 )
1717 }
1718
1719 pub fn bindings_for_action_in(
1720 &self,
1721 action: &dyn Action,
1722 focus_handle: &FocusHandle,
1723 ) -> Vec<KeyBinding> {
1724 let dispatch_tree = &self.window.rendered_frame.dispatch_tree;
1725
1726 let Some(node_id) = dispatch_tree.focusable_node_id(focus_handle.id) else {
1727 return vec![];
1728 };
1729 let context_stack = dispatch_tree
1730 .dispatch_path(node_id)
1731 .into_iter()
1732 .filter_map(|node_id| dispatch_tree.node(node_id).context.clone())
1733 .collect();
1734 dispatch_tree.bindings_for_action(action, &context_stack)
1735 }
1736
1737 pub fn listener_for<V: Render, E>(
1738 &self,
1739 view: &View<V>,
1740 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
1741 ) -> impl Fn(&E, &mut WindowContext) + 'static {
1742 let view = view.downgrade();
1743 move |e: &E, cx: &mut WindowContext| {
1744 view.update(cx, |view, cx| f(view, e, cx)).ok();
1745 }
1746 }
1747
1748 pub fn handler_for<V: Render>(
1749 &self,
1750 view: &View<V>,
1751 f: impl Fn(&mut V, &mut ViewContext<V>) + 'static,
1752 ) -> impl Fn(&mut WindowContext) {
1753 let view = view.downgrade();
1754 move |cx: &mut WindowContext| {
1755 view.update(cx, |view, cx| f(view, cx)).ok();
1756 }
1757 }
1758
1759 //========== ELEMENT RELATED FUNCTIONS ===========
1760 pub fn with_key_dispatch<R>(
1761 &mut self,
1762 context: Option<KeyContext>,
1763 focus_handle: Option<FocusHandle>,
1764 f: impl FnOnce(Option<FocusHandle>, &mut Self) -> R,
1765 ) -> R {
1766 let window = &mut self.window;
1767 window.next_frame.dispatch_tree.push_node(context.clone());
1768 if let Some(focus_handle) = focus_handle.as_ref() {
1769 window
1770 .next_frame
1771 .dispatch_tree
1772 .make_focusable(focus_handle.id);
1773 }
1774 let result = f(focus_handle, self);
1775
1776 self.window.next_frame.dispatch_tree.pop_node();
1777
1778 result
1779 }
1780
1781 /// Set an input handler, such as [ElementInputHandler], which interfaces with the
1782 /// platform to receive textual input with proper integration with concerns such
1783 /// as IME interactions.
1784 pub fn handle_input(
1785 &mut self,
1786 focus_handle: &FocusHandle,
1787 input_handler: impl PlatformInputHandler,
1788 ) {
1789 if focus_handle.is_focused(self) {
1790 self.window
1791 .platform_window
1792 .set_input_handler(Box::new(input_handler));
1793 }
1794 }
1795
1796 pub fn on_window_should_close(&mut self, f: impl Fn(&mut WindowContext) -> bool + 'static) {
1797 let mut this = self.to_async();
1798 self.window
1799 .platform_window
1800 .on_should_close(Box::new(move || this.update(|_, cx| f(cx)).unwrap_or(true)))
1801 }
1802}
1803
1804impl Context for WindowContext<'_> {
1805 type Result<T> = T;
1806
1807 fn build_model<T>(
1808 &mut self,
1809 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
1810 ) -> Model<T>
1811 where
1812 T: 'static,
1813 {
1814 let slot = self.app.entities.reserve();
1815 let model = build_model(&mut ModelContext::new(&mut *self.app, slot.downgrade()));
1816 self.entities.insert(slot, model)
1817 }
1818
1819 fn update_model<T: 'static, R>(
1820 &mut self,
1821 model: &Model<T>,
1822 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
1823 ) -> R {
1824 let mut entity = self.entities.lease(model);
1825 let result = update(
1826 &mut *entity,
1827 &mut ModelContext::new(&mut *self.app, model.downgrade()),
1828 );
1829 self.entities.end_lease(entity);
1830 result
1831 }
1832
1833 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
1834 where
1835 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
1836 {
1837 if window == self.window.handle {
1838 let root_view = self.window.root_view.clone().unwrap();
1839 Ok(update(root_view, self))
1840 } else {
1841 window.update(self.app, update)
1842 }
1843 }
1844
1845 fn read_model<T, R>(
1846 &self,
1847 handle: &Model<T>,
1848 read: impl FnOnce(&T, &AppContext) -> R,
1849 ) -> Self::Result<R>
1850 where
1851 T: 'static,
1852 {
1853 let entity = self.entities.read(handle);
1854 read(&*entity, &*self.app)
1855 }
1856
1857 fn read_window<T, R>(
1858 &self,
1859 window: &WindowHandle<T>,
1860 read: impl FnOnce(View<T>, &AppContext) -> R,
1861 ) -> Result<R>
1862 where
1863 T: 'static,
1864 {
1865 if window.any_handle == self.window.handle {
1866 let root_view = self
1867 .window
1868 .root_view
1869 .clone()
1870 .unwrap()
1871 .downcast::<T>()
1872 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
1873 Ok(read(root_view, self))
1874 } else {
1875 self.app.read_window(window, read)
1876 }
1877 }
1878}
1879
1880impl VisualContext for WindowContext<'_> {
1881 fn build_view<V>(
1882 &mut self,
1883 build_view_state: impl FnOnce(&mut ViewContext<'_, V>) -> V,
1884 ) -> Self::Result<View<V>>
1885 where
1886 V: 'static + Render,
1887 {
1888 let slot = self.app.entities.reserve();
1889 let view = View {
1890 model: slot.clone(),
1891 };
1892 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
1893 let entity = build_view_state(&mut cx);
1894 cx.entities.insert(slot, entity);
1895
1896 cx.new_view_observers
1897 .clone()
1898 .retain(&TypeId::of::<V>(), |observer| {
1899 let any_view = AnyView::from(view.clone());
1900 (observer)(any_view, self);
1901 true
1902 });
1903
1904 view
1905 }
1906
1907 /// Update the given view. Prefer calling `View::update` instead, which calls this method.
1908 fn update_view<T: 'static, R>(
1909 &mut self,
1910 view: &View<T>,
1911 update: impl FnOnce(&mut T, &mut ViewContext<'_, T>) -> R,
1912 ) -> Self::Result<R> {
1913 let mut lease = self.app.entities.lease(&view.model);
1914 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
1915 let result = update(&mut *lease, &mut cx);
1916 cx.app.entities.end_lease(lease);
1917 result
1918 }
1919
1920 fn replace_root_view<V>(
1921 &mut self,
1922 build_view: impl FnOnce(&mut ViewContext<'_, V>) -> V,
1923 ) -> Self::Result<View<V>>
1924 where
1925 V: 'static + Render,
1926 {
1927 let slot = self.app.entities.reserve();
1928 let view = View {
1929 model: slot.clone(),
1930 };
1931 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
1932 let entity = build_view(&mut cx);
1933 self.entities.insert(slot, entity);
1934 self.window.root_view = Some(view.clone().into());
1935 view
1936 }
1937
1938 fn focus_view<V: crate::FocusableView>(&mut self, view: &View<V>) -> Self::Result<()> {
1939 self.update_view(view, |view, cx| {
1940 view.focus_handle(cx).clone().focus(cx);
1941 })
1942 }
1943
1944 fn dismiss_view<V>(&mut self, view: &View<V>) -> Self::Result<()>
1945 where
1946 V: ManagedView,
1947 {
1948 self.update_view(view, |_, cx| cx.emit(DismissEvent))
1949 }
1950}
1951
1952impl<'a> std::ops::Deref for WindowContext<'a> {
1953 type Target = AppContext;
1954
1955 fn deref(&self) -> &Self::Target {
1956 &self.app
1957 }
1958}
1959
1960impl<'a> std::ops::DerefMut for WindowContext<'a> {
1961 fn deref_mut(&mut self) -> &mut Self::Target {
1962 &mut self.app
1963 }
1964}
1965
1966impl<'a> Borrow<AppContext> for WindowContext<'a> {
1967 fn borrow(&self) -> &AppContext {
1968 &self.app
1969 }
1970}
1971
1972impl<'a> BorrowMut<AppContext> for WindowContext<'a> {
1973 fn borrow_mut(&mut self) -> &mut AppContext {
1974 &mut self.app
1975 }
1976}
1977
1978pub trait BorrowWindow: BorrowMut<Window> + BorrowMut<AppContext> {
1979 fn app_mut(&mut self) -> &mut AppContext {
1980 self.borrow_mut()
1981 }
1982
1983 fn app(&self) -> &AppContext {
1984 self.borrow()
1985 }
1986
1987 fn window(&self) -> &Window {
1988 self.borrow()
1989 }
1990
1991 fn window_mut(&mut self) -> &mut Window {
1992 self.borrow_mut()
1993 }
1994
1995 /// Pushes the given element id onto the global stack and invokes the given closure
1996 /// with a `GlobalElementId`, which disambiguates the given id in the context of its ancestor
1997 /// ids. Because elements are discarded and recreated on each frame, the `GlobalElementId` is
1998 /// used to associate state with identified elements across separate frames.
1999 fn with_element_id<R>(
2000 &mut self,
2001 id: Option<impl Into<ElementId>>,
2002 f: impl FnOnce(&mut Self) -> R,
2003 ) -> R {
2004 if let Some(id) = id.map(Into::into) {
2005 let window = self.window_mut();
2006 window.element_id_stack.push(id.into());
2007 let result = f(self);
2008 let window: &mut Window = self.borrow_mut();
2009 window.element_id_stack.pop();
2010 result
2011 } else {
2012 f(self)
2013 }
2014 }
2015
2016 /// Invoke the given function with the given content mask after intersecting it
2017 /// with the current mask.
2018 fn with_content_mask<R>(
2019 &mut self,
2020 mask: Option<ContentMask<Pixels>>,
2021 f: impl FnOnce(&mut Self) -> R,
2022 ) -> R {
2023 if let Some(mask) = mask {
2024 let mask = mask.intersect(&self.content_mask());
2025 self.window_mut().next_frame.content_mask_stack.push(mask);
2026 let result = f(self);
2027 self.window_mut().next_frame.content_mask_stack.pop();
2028 result
2029 } else {
2030 f(self)
2031 }
2032 }
2033
2034 /// Invoke the given function with the content mask reset to that
2035 /// of the window.
2036 fn break_content_mask<R>(&mut self, f: impl FnOnce(&mut Self) -> R) -> R {
2037 let mask = ContentMask {
2038 bounds: Bounds {
2039 origin: Point::default(),
2040 size: self.window().viewport_size,
2041 },
2042 };
2043 self.window_mut().next_frame.content_mask_stack.push(mask);
2044 let result = f(self);
2045 self.window_mut().next_frame.content_mask_stack.pop();
2046 result
2047 }
2048
2049 /// Update the global element offset relative to the current offset. This is used to implement
2050 /// scrolling.
2051 fn with_element_offset<R>(
2052 &mut self,
2053 offset: Point<Pixels>,
2054 f: impl FnOnce(&mut Self) -> R,
2055 ) -> R {
2056 if offset.is_zero() {
2057 return f(self);
2058 };
2059
2060 let abs_offset = self.element_offset() + offset;
2061 self.with_absolute_element_offset(abs_offset, f)
2062 }
2063
2064 /// Update the global element offset based on the given offset. This is used to implement
2065 /// drag handles and other manual painting of elements.
2066 fn with_absolute_element_offset<R>(
2067 &mut self,
2068 offset: Point<Pixels>,
2069 f: impl FnOnce(&mut Self) -> R,
2070 ) -> R {
2071 self.window_mut()
2072 .next_frame
2073 .element_offset_stack
2074 .push(offset);
2075 let result = f(self);
2076 self.window_mut().next_frame.element_offset_stack.pop();
2077 result
2078 }
2079
2080 /// Obtain the current element offset.
2081 fn element_offset(&self) -> Point<Pixels> {
2082 self.window()
2083 .next_frame
2084 .element_offset_stack
2085 .last()
2086 .copied()
2087 .unwrap_or_default()
2088 }
2089
2090 /// Update or initialize state for an element with the given id that lives across multiple
2091 /// frames. If an element with this id existed in the rendered frame, its state will be passed
2092 /// to the given closure. The state returned by the closure will be stored so it can be referenced
2093 /// when drawing the next frame.
2094 fn with_element_state<S, R>(
2095 &mut self,
2096 id: ElementId,
2097 f: impl FnOnce(Option<S>, &mut Self) -> (R, S),
2098 ) -> R
2099 where
2100 S: 'static,
2101 {
2102 self.with_element_id(Some(id), |cx| {
2103 let global_id = cx.window().element_id_stack.clone();
2104
2105 if let Some(any) = cx
2106 .window_mut()
2107 .next_frame
2108 .element_states
2109 .remove(&global_id)
2110 .or_else(|| {
2111 cx.window_mut()
2112 .rendered_frame
2113 .element_states
2114 .remove(&global_id)
2115 })
2116 {
2117 let ElementStateBox {
2118 inner,
2119
2120 #[cfg(debug_assertions)]
2121 type_name
2122 } = any;
2123 // Using the extra inner option to avoid needing to reallocate a new box.
2124 let mut state_box = inner
2125 .downcast::<Option<S>>()
2126 .map_err(|_| {
2127 #[cfg(debug_assertions)]
2128 {
2129 anyhow!(
2130 "invalid element state type for id, requested_type {:?}, actual type: {:?}",
2131 std::any::type_name::<S>(),
2132 type_name
2133 )
2134 }
2135
2136 #[cfg(not(debug_assertions))]
2137 {
2138 anyhow!(
2139 "invalid element state type for id, requested_type {:?}",
2140 std::any::type_name::<S>(),
2141 )
2142 }
2143 })
2144 .unwrap();
2145
2146 // Actual: Option<AnyElement> <- View
2147 // Requested: () <- AnyElemet
2148 let state = state_box
2149 .take()
2150 .expect("element state is already on the stack");
2151 let (result, state) = f(Some(state), cx);
2152 state_box.replace(state);
2153 cx.window_mut()
2154 .next_frame
2155 .element_states
2156 .insert(global_id, ElementStateBox {
2157 inner: state_box,
2158
2159 #[cfg(debug_assertions)]
2160 type_name
2161 });
2162 result
2163 } else {
2164 let (result, state) = f(None, cx);
2165 cx.window_mut()
2166 .next_frame
2167 .element_states
2168 .insert(global_id,
2169 ElementStateBox {
2170 inner: Box::new(Some(state)),
2171
2172 #[cfg(debug_assertions)]
2173 type_name: std::any::type_name::<S>()
2174 }
2175
2176 );
2177 result
2178 }
2179 })
2180 }
2181
2182 /// Obtain the current content mask.
2183 fn content_mask(&self) -> ContentMask<Pixels> {
2184 self.window()
2185 .next_frame
2186 .content_mask_stack
2187 .last()
2188 .cloned()
2189 .unwrap_or_else(|| ContentMask {
2190 bounds: Bounds {
2191 origin: Point::default(),
2192 size: self.window().viewport_size,
2193 },
2194 })
2195 }
2196
2197 /// The size of an em for the base font of the application. Adjusting this value allows the
2198 /// UI to scale, just like zooming a web page.
2199 fn rem_size(&self) -> Pixels {
2200 self.window().rem_size
2201 }
2202}
2203
2204impl Borrow<Window> for WindowContext<'_> {
2205 fn borrow(&self) -> &Window {
2206 &self.window
2207 }
2208}
2209
2210impl BorrowMut<Window> for WindowContext<'_> {
2211 fn borrow_mut(&mut self) -> &mut Window {
2212 &mut self.window
2213 }
2214}
2215
2216impl<T> BorrowWindow for T where T: BorrowMut<AppContext> + BorrowMut<Window> {}
2217
2218pub struct ViewContext<'a, V> {
2219 window_cx: WindowContext<'a>,
2220 view: &'a View<V>,
2221}
2222
2223impl<V> Borrow<AppContext> for ViewContext<'_, V> {
2224 fn borrow(&self) -> &AppContext {
2225 &*self.window_cx.app
2226 }
2227}
2228
2229impl<V> BorrowMut<AppContext> for ViewContext<'_, V> {
2230 fn borrow_mut(&mut self) -> &mut AppContext {
2231 &mut *self.window_cx.app
2232 }
2233}
2234
2235impl<V> Borrow<Window> for ViewContext<'_, V> {
2236 fn borrow(&self) -> &Window {
2237 &*self.window_cx.window
2238 }
2239}
2240
2241impl<V> BorrowMut<Window> for ViewContext<'_, V> {
2242 fn borrow_mut(&mut self) -> &mut Window {
2243 &mut *self.window_cx.window
2244 }
2245}
2246
2247impl<'a, V: 'static> ViewContext<'a, V> {
2248 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window, view: &'a View<V>) -> Self {
2249 Self {
2250 window_cx: WindowContext::new(app, window),
2251 view,
2252 }
2253 }
2254
2255 pub fn entity_id(&self) -> EntityId {
2256 self.view.entity_id()
2257 }
2258
2259 pub fn view(&self) -> &View<V> {
2260 self.view
2261 }
2262
2263 pub fn model(&self) -> &Model<V> {
2264 &self.view.model
2265 }
2266
2267 /// Access the underlying window context.
2268 pub fn window_context(&mut self) -> &mut WindowContext<'a> {
2269 &mut self.window_cx
2270 }
2271
2272 pub fn with_z_index<R>(&mut self, z_index: u8, f: impl FnOnce(&mut Self) -> R) -> R {
2273 self.window.next_frame.z_index_stack.push(z_index);
2274 let result = f(self);
2275 self.window.next_frame.z_index_stack.pop();
2276 result
2277 }
2278
2279 pub fn on_next_frame(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static)
2280 where
2281 V: 'static,
2282 {
2283 let view = self.view().clone();
2284 self.window_cx.on_next_frame(move |cx| view.update(cx, f));
2285 }
2286
2287 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
2288 /// that are currently on the stack to be returned to the app.
2289 pub fn defer(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static) {
2290 let view = self.view().downgrade();
2291 self.window_cx.defer(move |cx| {
2292 view.update(cx, f).ok();
2293 });
2294 }
2295
2296 pub fn observe<V2, E>(
2297 &mut self,
2298 entity: &E,
2299 mut on_notify: impl FnMut(&mut V, E, &mut ViewContext<'_, V>) + 'static,
2300 ) -> Subscription
2301 where
2302 V2: 'static,
2303 V: 'static,
2304 E: Entity<V2>,
2305 {
2306 let view = self.view().downgrade();
2307 let entity_id = entity.entity_id();
2308 let entity = entity.downgrade();
2309 let window_handle = self.window.handle;
2310 let (subscription, activate) = self.app.observers.insert(
2311 entity_id,
2312 Box::new(move |cx| {
2313 window_handle
2314 .update(cx, |_, cx| {
2315 if let Some(handle) = E::upgrade_from(&entity) {
2316 view.update(cx, |this, cx| on_notify(this, handle, cx))
2317 .is_ok()
2318 } else {
2319 false
2320 }
2321 })
2322 .unwrap_or(false)
2323 }),
2324 );
2325 self.app.defer(move |_| activate());
2326 subscription
2327 }
2328
2329 pub fn subscribe<V2, E, Evt>(
2330 &mut self,
2331 entity: &E,
2332 mut on_event: impl FnMut(&mut V, E, &Evt, &mut ViewContext<'_, V>) + 'static,
2333 ) -> Subscription
2334 where
2335 V2: EventEmitter<Evt>,
2336 E: Entity<V2>,
2337 Evt: 'static,
2338 {
2339 let view = self.view().downgrade();
2340 let entity_id = entity.entity_id();
2341 let handle = entity.downgrade();
2342 let window_handle = self.window.handle;
2343 let (subscription, activate) = self.app.event_listeners.insert(
2344 entity_id,
2345 (
2346 TypeId::of::<Evt>(),
2347 Box::new(move |event, cx| {
2348 window_handle
2349 .update(cx, |_, cx| {
2350 if let Some(handle) = E::upgrade_from(&handle) {
2351 let event = event.downcast_ref().expect("invalid event type");
2352 view.update(cx, |this, cx| on_event(this, handle, event, cx))
2353 .is_ok()
2354 } else {
2355 false
2356 }
2357 })
2358 .unwrap_or(false)
2359 }),
2360 ),
2361 );
2362 self.app.defer(move |_| activate());
2363 subscription
2364 }
2365
2366 pub fn on_release(
2367 &mut self,
2368 on_release: impl FnOnce(&mut V, &mut WindowContext) + 'static,
2369 ) -> Subscription {
2370 let window_handle = self.window.handle;
2371 let (subscription, activate) = self.app.release_listeners.insert(
2372 self.view.model.entity_id,
2373 Box::new(move |this, cx| {
2374 let this = this.downcast_mut().expect("invalid entity type");
2375 let _ = window_handle.update(cx, |_, cx| on_release(this, cx));
2376 }),
2377 );
2378 activate();
2379 subscription
2380 }
2381
2382 pub fn observe_release<V2, E>(
2383 &mut self,
2384 entity: &E,
2385 mut on_release: impl FnMut(&mut V, &mut V2, &mut ViewContext<'_, V>) + 'static,
2386 ) -> Subscription
2387 where
2388 V: 'static,
2389 V2: 'static,
2390 E: Entity<V2>,
2391 {
2392 let view = self.view().downgrade();
2393 let entity_id = entity.entity_id();
2394 let window_handle = self.window.handle;
2395 let (subscription, activate) = self.app.release_listeners.insert(
2396 entity_id,
2397 Box::new(move |entity, cx| {
2398 let entity = entity.downcast_mut().expect("invalid entity type");
2399 let _ = window_handle.update(cx, |_, cx| {
2400 view.update(cx, |this, cx| on_release(this, entity, cx))
2401 });
2402 }),
2403 );
2404 activate();
2405 subscription
2406 }
2407
2408 pub fn notify(&mut self) {
2409 if !self.window.drawing {
2410 self.window_cx.notify();
2411 self.window_cx.app.push_effect(Effect::Notify {
2412 emitter: self.view.model.entity_id,
2413 });
2414 }
2415 }
2416
2417 pub fn observe_window_bounds(
2418 &mut self,
2419 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2420 ) -> Subscription {
2421 let view = self.view.downgrade();
2422 let (subscription, activate) = self.window.bounds_observers.insert(
2423 (),
2424 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
2425 );
2426 activate();
2427 subscription
2428 }
2429
2430 pub fn observe_window_activation(
2431 &mut self,
2432 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2433 ) -> Subscription {
2434 let view = self.view.downgrade();
2435 let (subscription, activate) = self.window.activation_observers.insert(
2436 (),
2437 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
2438 );
2439 activate();
2440 subscription
2441 }
2442
2443 /// Register a listener to be called when the given focus handle receives focus.
2444 /// Unlike [on_focus_changed], returns a subscription and persists until the subscription
2445 /// is dropped.
2446 pub fn on_focus(
2447 &mut self,
2448 handle: &FocusHandle,
2449 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2450 ) -> Subscription {
2451 let view = self.view.downgrade();
2452 let focus_id = handle.id;
2453 let (subscription, activate) = self.window.focus_listeners.insert(
2454 (),
2455 Box::new(move |event, cx| {
2456 view.update(cx, |view, cx| {
2457 if event.previous_focus_path.last() != Some(&focus_id)
2458 && event.current_focus_path.last() == Some(&focus_id)
2459 {
2460 listener(view, cx)
2461 }
2462 })
2463 .is_ok()
2464 }),
2465 );
2466 self.app.defer(move |_| activate());
2467 subscription
2468 }
2469
2470 /// Register a listener to be called when the given focus handle or one of its descendants receives focus.
2471 /// Unlike [on_focus_changed], returns a subscription and persists until the subscription
2472 /// is dropped.
2473 pub fn on_focus_in(
2474 &mut self,
2475 handle: &FocusHandle,
2476 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2477 ) -> Subscription {
2478 let view = self.view.downgrade();
2479 let focus_id = handle.id;
2480 let (subscription, activate) = self.window.focus_listeners.insert(
2481 (),
2482 Box::new(move |event, cx| {
2483 view.update(cx, |view, cx| {
2484 if !event.previous_focus_path.contains(&focus_id)
2485 && event.current_focus_path.contains(&focus_id)
2486 {
2487 listener(view, cx)
2488 }
2489 })
2490 .is_ok()
2491 }),
2492 );
2493 self.app.defer(move |_| activate());
2494 subscription
2495 }
2496
2497 /// Register a listener to be called when the given focus handle loses focus.
2498 /// Unlike [on_focus_changed], returns a subscription and persists until the subscription
2499 /// is dropped.
2500 pub fn on_blur(
2501 &mut self,
2502 handle: &FocusHandle,
2503 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2504 ) -> Subscription {
2505 let view = self.view.downgrade();
2506 let focus_id = handle.id;
2507 let (subscription, activate) = self.window.focus_listeners.insert(
2508 (),
2509 Box::new(move |event, cx| {
2510 view.update(cx, |view, cx| {
2511 if event.previous_focus_path.last() == Some(&focus_id)
2512 && event.current_focus_path.last() != Some(&focus_id)
2513 {
2514 listener(view, cx)
2515 }
2516 })
2517 .is_ok()
2518 }),
2519 );
2520 self.app.defer(move |_| activate());
2521 subscription
2522 }
2523
2524 /// Register a listener to be called when the window loses focus.
2525 /// Unlike [on_focus_changed], returns a subscription and persists until the subscription
2526 /// is dropped.
2527 pub fn on_blur_window(
2528 &mut self,
2529 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2530 ) -> Subscription {
2531 let view = self.view.downgrade();
2532 let (subscription, activate) = self.window.blur_listeners.insert(
2533 (),
2534 Box::new(move |cx| view.update(cx, |view, cx| listener(view, cx)).is_ok()),
2535 );
2536 activate();
2537 subscription
2538 }
2539
2540 /// Register a listener to be called when the given focus handle or one of its descendants loses focus.
2541 /// Unlike [on_focus_changed], returns a subscription and persists until the subscription
2542 /// is dropped.
2543 pub fn on_focus_out(
2544 &mut self,
2545 handle: &FocusHandle,
2546 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2547 ) -> Subscription {
2548 let view = self.view.downgrade();
2549 let focus_id = handle.id;
2550 let (subscription, activate) = self.window.focus_listeners.insert(
2551 (),
2552 Box::new(move |event, cx| {
2553 view.update(cx, |view, cx| {
2554 if event.previous_focus_path.contains(&focus_id)
2555 && !event.current_focus_path.contains(&focus_id)
2556 {
2557 listener(view, cx)
2558 }
2559 })
2560 .is_ok()
2561 }),
2562 );
2563 self.app.defer(move |_| activate());
2564 subscription
2565 }
2566
2567 pub fn spawn<Fut, R>(
2568 &mut self,
2569 f: impl FnOnce(WeakView<V>, AsyncWindowContext) -> Fut,
2570 ) -> Task<R>
2571 where
2572 R: 'static,
2573 Fut: Future<Output = R> + 'static,
2574 {
2575 let view = self.view().downgrade();
2576 self.window_cx.spawn(|cx| f(view, cx))
2577 }
2578
2579 pub fn update_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
2580 where
2581 G: 'static,
2582 {
2583 let mut global = self.app.lease_global::<G>();
2584 let result = f(&mut global, self);
2585 self.app.end_global_lease(global);
2586 result
2587 }
2588
2589 pub fn observe_global<G: 'static>(
2590 &mut self,
2591 mut f: impl FnMut(&mut V, &mut ViewContext<'_, V>) + 'static,
2592 ) -> Subscription {
2593 let window_handle = self.window.handle;
2594 let view = self.view().downgrade();
2595 let (subscription, activate) = self.global_observers.insert(
2596 TypeId::of::<G>(),
2597 Box::new(move |cx| {
2598 window_handle
2599 .update(cx, |_, cx| view.update(cx, |view, cx| f(view, cx)).is_ok())
2600 .unwrap_or(false)
2601 }),
2602 );
2603 self.app.defer(move |_| activate());
2604 subscription
2605 }
2606
2607 pub fn on_mouse_event<Event: 'static>(
2608 &mut self,
2609 handler: impl Fn(&mut V, &Event, DispatchPhase, &mut ViewContext<V>) + 'static,
2610 ) {
2611 let handle = self.view().clone();
2612 self.window_cx.on_mouse_event(move |event, phase, cx| {
2613 handle.update(cx, |view, cx| {
2614 handler(view, event, phase, cx);
2615 })
2616 });
2617 }
2618
2619 pub fn on_key_event<Event: 'static>(
2620 &mut self,
2621 handler: impl Fn(&mut V, &Event, DispatchPhase, &mut ViewContext<V>) + 'static,
2622 ) {
2623 let handle = self.view().clone();
2624 self.window_cx.on_key_event(move |event, phase, cx| {
2625 handle.update(cx, |view, cx| {
2626 handler(view, event, phase, cx);
2627 })
2628 });
2629 }
2630
2631 pub fn on_action(
2632 &mut self,
2633 action_type: TypeId,
2634 listener: impl Fn(&mut V, &dyn Any, DispatchPhase, &mut ViewContext<V>) + 'static,
2635 ) {
2636 let handle = self.view().clone();
2637 self.window_cx
2638 .on_action(action_type, move |action, phase, cx| {
2639 handle.update(cx, |view, cx| {
2640 listener(view, action, phase, cx);
2641 })
2642 });
2643 }
2644
2645 pub fn emit<Evt>(&mut self, event: Evt)
2646 where
2647 Evt: 'static,
2648 V: EventEmitter<Evt>,
2649 {
2650 let emitter = self.view.model.entity_id;
2651 self.app.push_effect(Effect::Emit {
2652 emitter,
2653 event_type: TypeId::of::<Evt>(),
2654 event: Box::new(event),
2655 });
2656 }
2657
2658 pub fn focus_self(&mut self)
2659 where
2660 V: FocusableView,
2661 {
2662 self.defer(|view, cx| view.focus_handle(cx).focus(cx))
2663 }
2664
2665 pub fn dismiss_self(&mut self)
2666 where
2667 V: ManagedView,
2668 {
2669 self.defer(|_, cx| cx.emit(DismissEvent))
2670 }
2671
2672 pub fn listener<E>(
2673 &self,
2674 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
2675 ) -> impl Fn(&E, &mut WindowContext) + 'static {
2676 let view = self.view().downgrade();
2677 move |e: &E, cx: &mut WindowContext| {
2678 view.update(cx, |view, cx| f(view, e, cx)).ok();
2679 }
2680 }
2681}
2682
2683impl<V> Context for ViewContext<'_, V> {
2684 type Result<U> = U;
2685
2686 fn build_model<T: 'static>(
2687 &mut self,
2688 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
2689 ) -> Model<T> {
2690 self.window_cx.build_model(build_model)
2691 }
2692
2693 fn update_model<T: 'static, R>(
2694 &mut self,
2695 model: &Model<T>,
2696 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
2697 ) -> R {
2698 self.window_cx.update_model(model, update)
2699 }
2700
2701 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
2702 where
2703 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
2704 {
2705 self.window_cx.update_window(window, update)
2706 }
2707
2708 fn read_model<T, R>(
2709 &self,
2710 handle: &Model<T>,
2711 read: impl FnOnce(&T, &AppContext) -> R,
2712 ) -> Self::Result<R>
2713 where
2714 T: 'static,
2715 {
2716 self.window_cx.read_model(handle, read)
2717 }
2718
2719 fn read_window<T, R>(
2720 &self,
2721 window: &WindowHandle<T>,
2722 read: impl FnOnce(View<T>, &AppContext) -> R,
2723 ) -> Result<R>
2724 where
2725 T: 'static,
2726 {
2727 self.window_cx.read_window(window, read)
2728 }
2729}
2730
2731impl<V: 'static> VisualContext for ViewContext<'_, V> {
2732 fn build_view<W: Render + 'static>(
2733 &mut self,
2734 build_view_state: impl FnOnce(&mut ViewContext<'_, W>) -> W,
2735 ) -> Self::Result<View<W>> {
2736 self.window_cx.build_view(build_view_state)
2737 }
2738
2739 fn update_view<V2: 'static, R>(
2740 &mut self,
2741 view: &View<V2>,
2742 update: impl FnOnce(&mut V2, &mut ViewContext<'_, V2>) -> R,
2743 ) -> Self::Result<R> {
2744 self.window_cx.update_view(view, update)
2745 }
2746
2747 fn replace_root_view<W>(
2748 &mut self,
2749 build_view: impl FnOnce(&mut ViewContext<'_, W>) -> W,
2750 ) -> Self::Result<View<W>>
2751 where
2752 W: 'static + Render,
2753 {
2754 self.window_cx.replace_root_view(build_view)
2755 }
2756
2757 fn focus_view<W: FocusableView>(&mut self, view: &View<W>) -> Self::Result<()> {
2758 self.window_cx.focus_view(view)
2759 }
2760
2761 fn dismiss_view<W: ManagedView>(&mut self, view: &View<W>) -> Self::Result<()> {
2762 self.window_cx.dismiss_view(view)
2763 }
2764}
2765
2766impl<'a, V> std::ops::Deref for ViewContext<'a, V> {
2767 type Target = WindowContext<'a>;
2768
2769 fn deref(&self) -> &Self::Target {
2770 &self.window_cx
2771 }
2772}
2773
2774impl<'a, V> std::ops::DerefMut for ViewContext<'a, V> {
2775 fn deref_mut(&mut self) -> &mut Self::Target {
2776 &mut self.window_cx
2777 }
2778}
2779
2780// #[derive(Clone, Copy, Eq, PartialEq, Hash)]
2781slotmap::new_key_type! { pub struct WindowId; }
2782
2783impl WindowId {
2784 pub fn as_u64(&self) -> u64 {
2785 self.0.as_ffi()
2786 }
2787}
2788
2789#[derive(Deref, DerefMut)]
2790pub struct WindowHandle<V> {
2791 #[deref]
2792 #[deref_mut]
2793 pub(crate) any_handle: AnyWindowHandle,
2794 state_type: PhantomData<V>,
2795}
2796
2797impl<V: 'static + Render> WindowHandle<V> {
2798 pub fn new(id: WindowId) -> Self {
2799 WindowHandle {
2800 any_handle: AnyWindowHandle {
2801 id,
2802 state_type: TypeId::of::<V>(),
2803 },
2804 state_type: PhantomData,
2805 }
2806 }
2807
2808 pub fn root<C>(&self, cx: &mut C) -> Result<View<V>>
2809 where
2810 C: Context,
2811 {
2812 Flatten::flatten(cx.update_window(self.any_handle, |root_view, _| {
2813 root_view
2814 .downcast::<V>()
2815 .map_err(|_| anyhow!("the type of the window's root view has changed"))
2816 }))
2817 }
2818
2819 pub fn update<C, R>(
2820 &self,
2821 cx: &mut C,
2822 update: impl FnOnce(&mut V, &mut ViewContext<'_, V>) -> R,
2823 ) -> Result<R>
2824 where
2825 C: Context,
2826 {
2827 cx.update_window(self.any_handle, |root_view, cx| {
2828 let view = root_view
2829 .downcast::<V>()
2830 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
2831 Ok(cx.update_view(&view, update))
2832 })?
2833 }
2834
2835 pub fn read<'a>(&self, cx: &'a AppContext) -> Result<&'a V> {
2836 let x = cx
2837 .windows
2838 .get(self.id)
2839 .and_then(|window| {
2840 window
2841 .as_ref()
2842 .and_then(|window| window.root_view.clone())
2843 .map(|root_view| root_view.downcast::<V>())
2844 })
2845 .ok_or_else(|| anyhow!("window not found"))?
2846 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
2847
2848 Ok(x.read(cx))
2849 }
2850
2851 pub fn read_with<C, R>(&self, cx: &C, read_with: impl FnOnce(&V, &AppContext) -> R) -> Result<R>
2852 where
2853 C: Context,
2854 {
2855 cx.read_window(self, |root_view, cx| read_with(root_view.read(cx), cx))
2856 }
2857
2858 pub fn root_view<C>(&self, cx: &C) -> Result<View<V>>
2859 where
2860 C: Context,
2861 {
2862 cx.read_window(self, |root_view, _cx| root_view.clone())
2863 }
2864
2865 pub fn is_active(&self, cx: &AppContext) -> Option<bool> {
2866 cx.windows
2867 .get(self.id)
2868 .and_then(|window| window.as_ref().map(|window| window.active))
2869 }
2870}
2871
2872impl<V> Copy for WindowHandle<V> {}
2873
2874impl<V> Clone for WindowHandle<V> {
2875 fn clone(&self) -> Self {
2876 WindowHandle {
2877 any_handle: self.any_handle,
2878 state_type: PhantomData,
2879 }
2880 }
2881}
2882
2883impl<V> PartialEq for WindowHandle<V> {
2884 fn eq(&self, other: &Self) -> bool {
2885 self.any_handle == other.any_handle
2886 }
2887}
2888
2889impl<V> Eq for WindowHandle<V> {}
2890
2891impl<V> Hash for WindowHandle<V> {
2892 fn hash<H: Hasher>(&self, state: &mut H) {
2893 self.any_handle.hash(state);
2894 }
2895}
2896
2897impl<V: 'static> Into<AnyWindowHandle> for WindowHandle<V> {
2898 fn into(self) -> AnyWindowHandle {
2899 self.any_handle
2900 }
2901}
2902
2903#[derive(Copy, Clone, PartialEq, Eq, Hash)]
2904pub struct AnyWindowHandle {
2905 pub(crate) id: WindowId,
2906 state_type: TypeId,
2907}
2908
2909impl AnyWindowHandle {
2910 pub fn window_id(&self) -> WindowId {
2911 self.id
2912 }
2913
2914 pub fn downcast<T: 'static>(&self) -> Option<WindowHandle<T>> {
2915 if TypeId::of::<T>() == self.state_type {
2916 Some(WindowHandle {
2917 any_handle: *self,
2918 state_type: PhantomData,
2919 })
2920 } else {
2921 None
2922 }
2923 }
2924
2925 pub fn update<C, R>(
2926 self,
2927 cx: &mut C,
2928 update: impl FnOnce(AnyView, &mut WindowContext<'_>) -> R,
2929 ) -> Result<R>
2930 where
2931 C: Context,
2932 {
2933 cx.update_window(self, update)
2934 }
2935
2936 pub fn read<T, C, R>(self, cx: &C, read: impl FnOnce(View<T>, &AppContext) -> R) -> Result<R>
2937 where
2938 C: Context,
2939 T: 'static,
2940 {
2941 let view = self
2942 .downcast::<T>()
2943 .context("the type of the window's root view has changed")?;
2944
2945 cx.read_window(&view, read)
2946 }
2947}
2948
2949// #[cfg(any(test, feature = "test-support"))]
2950// impl From<SmallVec<[u32; 16]>> for StackingOrder {
2951// fn from(small_vec: SmallVec<[u32; 16]>) -> Self {
2952// StackingOrder(small_vec)
2953// }
2954// }
2955
2956#[derive(Clone, Debug, Eq, PartialEq, Hash)]
2957pub enum ElementId {
2958 View(EntityId),
2959 Integer(usize),
2960 Name(SharedString),
2961 FocusHandle(FocusId),
2962 NamedInteger(SharedString, usize),
2963}
2964
2965impl ElementId {
2966 pub(crate) fn from_entity_id(entity_id: EntityId) -> Self {
2967 ElementId::View(entity_id)
2968 }
2969}
2970
2971impl TryInto<SharedString> for ElementId {
2972 type Error = anyhow::Error;
2973
2974 fn try_into(self) -> anyhow::Result<SharedString> {
2975 if let ElementId::Name(name) = self {
2976 Ok(name)
2977 } else {
2978 Err(anyhow!("element id is not string"))
2979 }
2980 }
2981}
2982
2983impl From<usize> for ElementId {
2984 fn from(id: usize) -> Self {
2985 ElementId::Integer(id)
2986 }
2987}
2988
2989impl From<i32> for ElementId {
2990 fn from(id: i32) -> Self {
2991 Self::Integer(id as usize)
2992 }
2993}
2994
2995impl From<SharedString> for ElementId {
2996 fn from(name: SharedString) -> Self {
2997 ElementId::Name(name)
2998 }
2999}
3000
3001impl From<&'static str> for ElementId {
3002 fn from(name: &'static str) -> Self {
3003 ElementId::Name(name.into())
3004 }
3005}
3006
3007impl<'a> From<&'a FocusHandle> for ElementId {
3008 fn from(handle: &'a FocusHandle) -> Self {
3009 ElementId::FocusHandle(handle.id)
3010 }
3011}
3012
3013impl From<(&'static str, EntityId)> for ElementId {
3014 fn from((name, id): (&'static str, EntityId)) -> Self {
3015 ElementId::NamedInteger(name.into(), id.as_u64() as usize)
3016 }
3017}
3018
3019impl From<(&'static str, usize)> for ElementId {
3020 fn from((name, id): (&'static str, usize)) -> Self {
3021 ElementId::NamedInteger(name.into(), id)
3022 }
3023}
3024
3025impl From<(&'static str, u64)> for ElementId {
3026 fn from((name, id): (&'static str, u64)) -> Self {
3027 ElementId::NamedInteger(name.into(), id as usize)
3028 }
3029}
3030
3031/// A rectangle, to be rendered on the screen by GPUI at the given position and size.
3032pub struct PaintQuad {
3033 bounds: Bounds<Pixels>,
3034 corner_radii: Corners<Pixels>,
3035 background: Hsla,
3036 border_widths: Edges<Pixels>,
3037 border_color: Hsla,
3038}
3039
3040impl PaintQuad {
3041 /// Set the corner radii of the quad.
3042 pub fn corner_radii(self, corner_radii: impl Into<Corners<Pixels>>) -> Self {
3043 PaintQuad {
3044 corner_radii: corner_radii.into(),
3045 ..self
3046 }
3047 }
3048
3049 /// Set the border widths of the quad.
3050 pub fn border_widths(self, border_widths: impl Into<Edges<Pixels>>) -> Self {
3051 PaintQuad {
3052 border_widths: border_widths.into(),
3053 ..self
3054 }
3055 }
3056
3057 /// Set the border color of the quad.
3058 pub fn border_color(self, border_color: impl Into<Hsla>) -> Self {
3059 PaintQuad {
3060 border_color: border_color.into(),
3061 ..self
3062 }
3063 }
3064
3065 /// Set the background color of the quad.
3066 pub fn background(self, background: impl Into<Hsla>) -> Self {
3067 PaintQuad {
3068 background: background.into(),
3069 ..self
3070 }
3071 }
3072}
3073
3074/// Create a quad with the given parameters.
3075pub fn quad(
3076 bounds: Bounds<Pixels>,
3077 corner_radii: impl Into<Corners<Pixels>>,
3078 background: impl Into<Hsla>,
3079 border_widths: impl Into<Edges<Pixels>>,
3080 border_color: impl Into<Hsla>,
3081) -> PaintQuad {
3082 PaintQuad {
3083 bounds,
3084 corner_radii: corner_radii.into(),
3085 background: background.into(),
3086 border_widths: border_widths.into(),
3087 border_color: border_color.into(),
3088 }
3089}
3090
3091/// Create a filled quad with the given bounds and background color.
3092pub fn fill(bounds: impl Into<Bounds<Pixels>>, background: impl Into<Hsla>) -> PaintQuad {
3093 PaintQuad {
3094 bounds: bounds.into(),
3095 corner_radii: (0.).into(),
3096 background: background.into(),
3097 border_widths: (0.).into(),
3098 border_color: transparent_black(),
3099 }
3100}
3101
3102/// Create a rectangle outline with the given bounds, border color, and a 1px border width
3103pub fn outline(bounds: impl Into<Bounds<Pixels>>, border_color: impl Into<Hsla>) -> PaintQuad {
3104 PaintQuad {
3105 bounds: bounds.into(),
3106 corner_radii: (0.).into(),
3107 background: transparent_black(),
3108 border_widths: (1.).into(),
3109 border_color: border_color.into(),
3110 }
3111}