1use crate::{
2 px, size, transparent_black, Action, AnyDrag, AnyView, AppContext, Arena, AsyncWindowContext,
3 AvailableSpace, Bounds, BoxShadow, Context, Corners, CursorStyle, DevicePixels,
4 DispatchActionListener, DispatchNodeId, DispatchTree, DisplayId, Edges, Effect, Entity,
5 EntityId, EventEmitter, FileDropEvent, Flatten, FontId, GlobalElementId, GlyphId, Hsla,
6 ImageData, InputEvent, IsZero, KeyBinding, KeyContext, KeyDownEvent, KeystrokeEvent, LayoutId,
7 Model, ModelContext, Modifiers, MonochromeSprite, MouseButton, MouseMoveEvent, MouseUpEvent,
8 Path, Pixels, PlatformAtlas, PlatformDisplay, PlatformInputHandler, PlatformWindow, Point,
9 PolychromeSprite, PromptLevel, Quad, Render, RenderGlyphParams, RenderImageParams,
10 RenderSvgParams, ScaledPixels, Scene, SceneBuilder, Shadow, SharedString, Size, Style,
11 SubscriberSet, Subscription, Surface, TaffyLayoutEngine, Task, Underline, UnderlineStyle, View,
12 VisualContext, WeakView, WindowBounds, WindowOptions, SUBPIXEL_VARIANTS,
13};
14use anyhow::{anyhow, Context as _, Result};
15use collections::{FxHashMap, FxHashSet};
16use derive_more::{Deref, DerefMut};
17use futures::{
18 channel::{mpsc, oneshot},
19 StreamExt,
20};
21use media::core_video::CVImageBuffer;
22use parking_lot::RwLock;
23use slotmap::SlotMap;
24use smallvec::SmallVec;
25use std::{
26 any::{Any, TypeId},
27 borrow::{Borrow, BorrowMut, Cow},
28 cell::RefCell,
29 collections::hash_map::Entry,
30 fmt::Debug,
31 future::Future,
32 hash::{Hash, Hasher},
33 marker::PhantomData,
34 mem,
35 rc::Rc,
36 sync::{
37 atomic::{AtomicUsize, Ordering::SeqCst},
38 Arc,
39 },
40};
41use util::{post_inc, ResultExt};
42
43const ACTIVE_DRAG_Z_INDEX: u8 = 1;
44
45/// A global stacking order, which is created by stacking successive z-index values.
46/// Each z-index will always be interpreted in the context of its parent z-index.
47#[derive(Deref, DerefMut, Clone, Ord, PartialOrd, PartialEq, Eq, Default)]
48pub struct StackingOrder {
49 #[deref]
50 #[deref_mut]
51 context_stack: SmallVec<[u8; 64]>,
52 id: u32,
53}
54
55impl std::fmt::Debug for StackingOrder {
56 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
57 let mut stacks = self.context_stack.iter().peekable();
58 write!(f, "[({}): ", self.id)?;
59 while let Some(z_index) = stacks.next() {
60 write!(f, "{z_index}")?;
61 if stacks.peek().is_some() {
62 write!(f, "->")?;
63 }
64 }
65 write!(f, "]")?;
66 Ok(())
67 }
68}
69
70/// Represents the two different phases when dispatching events.
71#[derive(Default, Copy, Clone, Debug, Eq, PartialEq)]
72pub enum DispatchPhase {
73 /// After the capture phase comes the bubble phase, in which mouse event listeners are
74 /// invoked front to back and keyboard event listeners are invoked from the focused element
75 /// to the root of the element tree. This is the phase you'll most commonly want to use when
76 /// registering event listeners.
77 #[default]
78 Bubble,
79 /// During the initial capture phase, mouse event listeners are invoked back to front, and keyboard
80 /// listeners are invoked from the root of the tree downward toward the focused element. This phase
81 /// is used for special purposes such as clearing the "pressed" state for click events. If
82 /// you stop event propagation during this phase, you need to know what you're doing. Handlers
83 /// outside of the immediate region may rely on detecting non-local events during this phase.
84 Capture,
85}
86
87impl DispatchPhase {
88 pub fn bubble(self) -> bool {
89 self == DispatchPhase::Bubble
90 }
91
92 pub fn capture(self) -> bool {
93 self == DispatchPhase::Capture
94 }
95}
96
97type AnyObserver = Box<dyn FnMut(&mut WindowContext) -> bool + 'static>;
98type AnyMouseListener = Box<dyn FnMut(&dyn Any, DispatchPhase, &mut WindowContext) + 'static>;
99type AnyWindowFocusListener = Box<dyn FnMut(&FocusEvent, &mut WindowContext) -> bool + 'static>;
100
101struct FocusEvent {
102 previous_focus_path: SmallVec<[FocusId; 8]>,
103 current_focus_path: SmallVec<[FocusId; 8]>,
104}
105
106slotmap::new_key_type! { pub struct FocusId; }
107
108thread_local! {
109 pub(crate) static ELEMENT_ARENA: RefCell<Arena> = RefCell::new(Arena::new(4 * 1024 * 1024));
110}
111
112impl FocusId {
113 /// Obtains whether the element associated with this handle is currently focused.
114 pub fn is_focused(&self, cx: &WindowContext) -> bool {
115 cx.window.focus == Some(*self)
116 }
117
118 /// Obtains whether the element associated with this handle contains the focused
119 /// element or is itself focused.
120 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
121 cx.focused()
122 .map_or(false, |focused| self.contains(focused.id, cx))
123 }
124
125 /// Obtains whether the element associated with this handle is contained within the
126 /// focused element or is itself focused.
127 pub fn within_focused(&self, cx: &WindowContext) -> bool {
128 let focused = cx.focused();
129 focused.map_or(false, |focused| focused.id.contains(*self, cx))
130 }
131
132 /// Obtains whether this handle contains the given handle in the most recently rendered frame.
133 pub(crate) fn contains(&self, other: Self, cx: &WindowContext) -> bool {
134 cx.window
135 .rendered_frame
136 .dispatch_tree
137 .focus_contains(*self, other)
138 }
139}
140
141/// A handle which can be used to track and manipulate the focused element in a window.
142pub struct FocusHandle {
143 pub(crate) id: FocusId,
144 handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
145}
146
147impl std::fmt::Debug for FocusHandle {
148 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
149 f.write_fmt(format_args!("FocusHandle({:?})", self.id))
150 }
151}
152
153impl FocusHandle {
154 pub(crate) fn new(handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>) -> Self {
155 let id = handles.write().insert(AtomicUsize::new(1));
156 Self {
157 id,
158 handles: handles.clone(),
159 }
160 }
161
162 pub(crate) fn for_id(
163 id: FocusId,
164 handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
165 ) -> Option<Self> {
166 let lock = handles.read();
167 let ref_count = lock.get(id)?;
168 if ref_count.load(SeqCst) == 0 {
169 None
170 } else {
171 ref_count.fetch_add(1, SeqCst);
172 Some(Self {
173 id,
174 handles: handles.clone(),
175 })
176 }
177 }
178
179 /// Moves the focus to the element associated with this handle.
180 pub fn focus(&self, cx: &mut WindowContext) {
181 cx.focus(self)
182 }
183
184 /// Obtains whether the element associated with this handle is currently focused.
185 pub fn is_focused(&self, cx: &WindowContext) -> bool {
186 self.id.is_focused(cx)
187 }
188
189 /// Obtains whether the element associated with this handle contains the focused
190 /// element or is itself focused.
191 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
192 self.id.contains_focused(cx)
193 }
194
195 /// Obtains whether the element associated with this handle is contained within the
196 /// focused element or is itself focused.
197 pub fn within_focused(&self, cx: &WindowContext) -> bool {
198 self.id.within_focused(cx)
199 }
200
201 /// Obtains whether this handle contains the given handle in the most recently rendered frame.
202 pub fn contains(&self, other: &Self, cx: &WindowContext) -> bool {
203 self.id.contains(other.id, cx)
204 }
205}
206
207impl Clone for FocusHandle {
208 fn clone(&self) -> Self {
209 Self::for_id(self.id, &self.handles).unwrap()
210 }
211}
212
213impl PartialEq for FocusHandle {
214 fn eq(&self, other: &Self) -> bool {
215 self.id == other.id
216 }
217}
218
219impl Eq for FocusHandle {}
220
221impl Drop for FocusHandle {
222 fn drop(&mut self) {
223 self.handles
224 .read()
225 .get(self.id)
226 .unwrap()
227 .fetch_sub(1, SeqCst);
228 }
229}
230
231/// FocusableView allows users of your view to easily
232/// focus it (using cx.focus_view(view))
233pub trait FocusableView: 'static + Render {
234 fn focus_handle(&self, cx: &AppContext) -> FocusHandle;
235}
236
237/// ManagedView is a view (like a Modal, Popover, Menu, etc.)
238/// where the lifecycle of the view is handled by another view.
239pub trait ManagedView: FocusableView + EventEmitter<DismissEvent> {}
240
241impl<M: FocusableView + EventEmitter<DismissEvent>> ManagedView for M {}
242
243pub struct DismissEvent;
244
245// Holds the state for a specific window.
246pub struct Window {
247 pub(crate) handle: AnyWindowHandle,
248 pub(crate) removed: bool,
249 pub(crate) platform_window: Box<dyn PlatformWindow>,
250 display_id: DisplayId,
251 sprite_atlas: Arc<dyn PlatformAtlas>,
252 rem_size: Pixels,
253 viewport_size: Size<Pixels>,
254 layout_engine: Option<TaffyLayoutEngine>,
255 pub(crate) root_view: Option<AnyView>,
256 pub(crate) element_id_stack: GlobalElementId,
257 pub(crate) rendered_frame: Frame,
258 pub(crate) next_frame: Frame,
259 pub(crate) dirty_views: FxHashSet<EntityId>,
260 pub(crate) focus_handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
261 focus_listeners: SubscriberSet<(), AnyWindowFocusListener>,
262 blur_listeners: SubscriberSet<(), AnyObserver>,
263 default_prevented: bool,
264 mouse_position: Point<Pixels>,
265 modifiers: Modifiers,
266 requested_cursor_style: Option<CursorStyle>,
267 scale_factor: f32,
268 bounds: WindowBounds,
269 bounds_observers: SubscriberSet<(), AnyObserver>,
270 active: bool,
271 pub(crate) dirty: bool,
272 pub(crate) drawing: bool,
273 activation_observers: SubscriberSet<(), AnyObserver>,
274 pub(crate) focus: Option<FocusId>,
275 focus_enabled: bool,
276
277 #[cfg(any(test, feature = "test-support"))]
278 pub(crate) focus_invalidated: bool,
279}
280
281pub(crate) struct ElementStateBox {
282 inner: Box<dyn Any>,
283 #[cfg(debug_assertions)]
284 type_name: &'static str,
285}
286
287pub(crate) struct Frame {
288 focus: Option<FocusId>,
289 pub(crate) element_states: FxHashMap<GlobalElementId, ElementStateBox>,
290 mouse_listeners: FxHashMap<TypeId, Vec<(StackingOrder, EntityId, AnyMouseListener)>>,
291 pub(crate) dispatch_tree: DispatchTree,
292 pub(crate) scene_builder: SceneBuilder,
293 pub(crate) depth_map: Vec<(StackingOrder, Bounds<Pixels>)>,
294 pub(crate) z_index_stack: StackingOrder,
295 pub(crate) next_stacking_order_id: u32,
296 content_mask_stack: Vec<ContentMask<Pixels>>,
297 element_offset_stack: Vec<Point<Pixels>>,
298 pub(crate) view_parents: FxHashMap<EntityId, EntityId>,
299 pub(crate) view_stack: Vec<EntityId>,
300 pub(crate) reused_views: FxHashSet<EntityId>,
301}
302
303impl Frame {
304 fn new(dispatch_tree: DispatchTree) -> Self {
305 Frame {
306 focus: None,
307 element_states: FxHashMap::default(),
308 mouse_listeners: FxHashMap::default(),
309 dispatch_tree,
310 scene_builder: SceneBuilder::default(),
311 z_index_stack: StackingOrder::default(),
312 next_stacking_order_id: 0,
313 depth_map: Default::default(),
314 content_mask_stack: Vec::new(),
315 element_offset_stack: Vec::new(),
316 view_parents: FxHashMap::default(),
317 view_stack: Vec::new(),
318 reused_views: FxHashSet::default(),
319 }
320 }
321
322 fn clear(&mut self) {
323 self.element_states.clear();
324 self.mouse_listeners.values_mut().for_each(Vec::clear);
325 self.dispatch_tree.clear();
326 self.depth_map.clear();
327 self.next_stacking_order_id = 0;
328 self.view_parents.clear();
329 debug_assert!(self.view_stack.is_empty());
330 self.reused_views.clear();
331 }
332
333 fn focus_path(&self) -> SmallVec<[FocusId; 8]> {
334 self.focus
335 .map(|focus_id| self.dispatch_tree.focus_path(focus_id))
336 .unwrap_or_default()
337 }
338}
339
340impl Window {
341 pub(crate) fn new(
342 handle: AnyWindowHandle,
343 options: WindowOptions,
344 cx: &mut AppContext,
345 ) -> Self {
346 let platform_window = cx.platform.open_window(
347 handle,
348 options,
349 Box::new({
350 let mut cx = cx.to_async();
351 move || handle.update(&mut cx, |_, cx| cx.draw())
352 }),
353 );
354 let display_id = platform_window.display().id();
355 let sprite_atlas = platform_window.sprite_atlas();
356 let mouse_position = platform_window.mouse_position();
357 let modifiers = platform_window.modifiers();
358 let content_size = platform_window.content_size();
359 let scale_factor = platform_window.scale_factor();
360 let bounds = platform_window.bounds();
361
362 platform_window.on_resize(Box::new({
363 let mut cx = cx.to_async();
364 move |_, _| {
365 handle
366 .update(&mut cx, |_, cx| cx.window_bounds_changed())
367 .log_err();
368 }
369 }));
370 platform_window.on_moved(Box::new({
371 let mut cx = cx.to_async();
372 move || {
373 handle
374 .update(&mut cx, |_, cx| cx.window_bounds_changed())
375 .log_err();
376 }
377 }));
378 platform_window.on_active_status_change(Box::new({
379 let mut cx = cx.to_async();
380 move |active| {
381 handle
382 .update(&mut cx, |_, cx| {
383 cx.window.active = active;
384 cx.window
385 .activation_observers
386 .clone()
387 .retain(&(), |callback| callback(cx));
388 })
389 .log_err();
390 }
391 }));
392
393 platform_window.on_input({
394 let mut cx = cx.to_async();
395 Box::new(move |event| {
396 handle
397 .update(&mut cx, |_, cx| cx.dispatch_event(event))
398 .log_err()
399 .unwrap_or(false)
400 })
401 });
402
403 Window {
404 handle,
405 removed: false,
406 platform_window,
407 display_id,
408 sprite_atlas,
409 rem_size: px(16.),
410 viewport_size: content_size,
411 layout_engine: Some(TaffyLayoutEngine::new()),
412 root_view: None,
413 element_id_stack: GlobalElementId::default(),
414 rendered_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
415 next_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
416 dirty_views: FxHashSet::default(),
417 focus_handles: Arc::new(RwLock::new(SlotMap::with_key())),
418 focus_listeners: SubscriberSet::new(),
419 blur_listeners: SubscriberSet::new(),
420 default_prevented: true,
421 mouse_position,
422 modifiers,
423 requested_cursor_style: None,
424 scale_factor,
425 bounds,
426 bounds_observers: SubscriberSet::new(),
427 active: false,
428 dirty: false,
429 drawing: false,
430 activation_observers: SubscriberSet::new(),
431 focus: None,
432 focus_enabled: true,
433
434 #[cfg(any(test, feature = "test-support"))]
435 focus_invalidated: false,
436 }
437 }
438}
439
440/// Indicates which region of the window is visible. Content falling outside of this mask will not be
441/// rendered. Currently, only rectangular content masks are supported, but we give the mask its own type
442/// to leave room to support more complex shapes in the future.
443#[derive(Clone, Debug, Default, PartialEq, Eq)]
444#[repr(C)]
445pub struct ContentMask<P: Clone + Default + Debug> {
446 pub bounds: Bounds<P>,
447}
448
449impl ContentMask<Pixels> {
450 /// Scale the content mask's pixel units by the given scaling factor.
451 pub fn scale(&self, factor: f32) -> ContentMask<ScaledPixels> {
452 ContentMask {
453 bounds: self.bounds.scale(factor),
454 }
455 }
456
457 /// Intersect the content mask with the given content mask.
458 pub fn intersect(&self, other: &Self) -> Self {
459 let bounds = self.bounds.intersect(&other.bounds);
460 ContentMask { bounds }
461 }
462}
463
464/// Provides access to application state in the context of a single window. Derefs
465/// to an `AppContext`, so you can also pass a `WindowContext` to any method that takes
466/// an `AppContext` and call any `AppContext` methods.
467pub struct WindowContext<'a> {
468 pub(crate) app: &'a mut AppContext,
469 pub(crate) window: &'a mut Window,
470}
471
472impl<'a> WindowContext<'a> {
473 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window) -> Self {
474 Self { app, window }
475 }
476
477 /// Obtain a handle to the window that belongs to this context.
478 pub fn window_handle(&self) -> AnyWindowHandle {
479 self.window.handle
480 }
481
482 /// Mark the window as dirty, scheduling it to be redrawn on the next frame.
483 pub fn notify(&mut self) {
484 if !self.window.drawing {
485 self.window.dirty = true;
486 }
487 }
488
489 /// Close this window.
490 pub fn remove_window(&mut self) {
491 self.window.removed = true;
492 }
493
494 /// Obtain a new `FocusHandle`, which allows you to track and manipulate the keyboard focus
495 /// for elements rendered within this window.
496 pub fn focus_handle(&mut self) -> FocusHandle {
497 FocusHandle::new(&self.window.focus_handles)
498 }
499
500 /// Obtain the currently focused `FocusHandle`. If no elements are focused, returns `None`.
501 pub fn focused(&self) -> Option<FocusHandle> {
502 self.window
503 .focus
504 .and_then(|id| FocusHandle::for_id(id, &self.window.focus_handles))
505 }
506
507 /// Move focus to the element associated with the given `FocusHandle`.
508 pub fn focus(&mut self, handle: &FocusHandle) {
509 if !self.window.focus_enabled || self.window.focus == Some(handle.id) {
510 return;
511 }
512
513 self.window.focus = Some(handle.id);
514 self.window
515 .rendered_frame
516 .dispatch_tree
517 .clear_pending_keystrokes();
518
519 #[cfg(any(test, feature = "test-support"))]
520 {
521 self.window.focus_invalidated = true;
522 }
523
524 self.notify();
525 }
526
527 /// Remove focus from all elements within this context's window.
528 pub fn blur(&mut self) {
529 if !self.window.focus_enabled {
530 return;
531 }
532
533 self.window.focus = None;
534 self.notify();
535 }
536
537 pub fn disable_focus(&mut self) {
538 self.blur();
539 self.window.focus_enabled = false;
540 }
541
542 pub fn dispatch_action(&mut self, action: Box<dyn Action>) {
543 let focus_handle = self.focused();
544
545 self.defer(move |cx| {
546 let node_id = focus_handle
547 .and_then(|handle| {
548 cx.window
549 .rendered_frame
550 .dispatch_tree
551 .focusable_node_id(handle.id)
552 })
553 .unwrap_or_else(|| cx.window.rendered_frame.dispatch_tree.root_node_id());
554
555 cx.propagate_event = true;
556 cx.dispatch_action_on_node(node_id, action);
557 })
558 }
559
560 pub(crate) fn dispatch_keystroke_observers(
561 &mut self,
562 event: &dyn Any,
563 action: Option<Box<dyn Action>>,
564 ) {
565 let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() else {
566 return;
567 };
568
569 self.keystroke_observers
570 .clone()
571 .retain(&(), move |callback| {
572 (callback)(
573 &KeystrokeEvent {
574 keystroke: key_down_event.keystroke.clone(),
575 action: action.as_ref().map(|action| action.boxed_clone()),
576 },
577 self,
578 );
579 true
580 });
581 }
582
583 pub(crate) fn clear_pending_keystrokes(&mut self) {
584 self.window
585 .rendered_frame
586 .dispatch_tree
587 .clear_pending_keystrokes();
588 self.window
589 .next_frame
590 .dispatch_tree
591 .clear_pending_keystrokes();
592 }
593
594 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
595 /// that are currently on the stack to be returned to the app.
596 pub fn defer(&mut self, f: impl FnOnce(&mut WindowContext) + 'static) {
597 let handle = self.window.handle;
598 self.app.defer(move |cx| {
599 handle.update(cx, |_, cx| f(cx)).ok();
600 });
601 }
602
603 pub fn subscribe<Emitter, E, Evt>(
604 &mut self,
605 entity: &E,
606 mut on_event: impl FnMut(E, &Evt, &mut WindowContext<'_>) + 'static,
607 ) -> Subscription
608 where
609 Emitter: EventEmitter<Evt>,
610 E: Entity<Emitter>,
611 Evt: 'static,
612 {
613 let entity_id = entity.entity_id();
614 let entity = entity.downgrade();
615 let window_handle = self.window.handle;
616 let (subscription, activate) = self.app.event_listeners.insert(
617 entity_id,
618 (
619 TypeId::of::<Evt>(),
620 Box::new(move |event, cx| {
621 window_handle
622 .update(cx, |_, cx| {
623 if let Some(handle) = E::upgrade_from(&entity) {
624 let event = event.downcast_ref().expect("invalid event type");
625 on_event(handle, event, cx);
626 true
627 } else {
628 false
629 }
630 })
631 .unwrap_or(false)
632 }),
633 ),
634 );
635 self.app.defer(move |_| activate());
636 subscription
637 }
638
639 /// Create an `AsyncWindowContext`, which has a static lifetime and can be held across
640 /// await points in async code.
641 pub fn to_async(&self) -> AsyncWindowContext {
642 AsyncWindowContext::new(self.app.to_async(), self.window.handle)
643 }
644
645 /// Schedule the given closure to be run directly after the current frame is rendered.
646 pub fn on_next_frame(&mut self, callback: impl FnOnce(&mut WindowContext) + 'static) {
647 let handle = self.window.handle;
648 let display_id = self.window.display_id;
649
650 let mut frame_consumers = std::mem::take(&mut self.app.frame_consumers);
651 if let Entry::Vacant(e) = frame_consumers.entry(display_id) {
652 let (tx, mut rx) = mpsc::unbounded::<()>();
653 self.platform.set_display_link_output_callback(
654 display_id,
655 Box::new(move |_current_time, _output_time| _ = tx.unbounded_send(())),
656 );
657
658 let consumer_task = self.app.spawn(|cx| async move {
659 while rx.next().await.is_some() {
660 cx.update(|cx| {
661 for callback in cx
662 .next_frame_callbacks
663 .get_mut(&display_id)
664 .unwrap()
665 .drain(..)
666 .collect::<SmallVec<[_; 32]>>()
667 {
668 callback(cx);
669 }
670 })
671 .ok();
672
673 // Flush effects, then stop the display link if no new next_frame_callbacks have been added.
674
675 cx.update(|cx| {
676 if cx.next_frame_callbacks.is_empty() {
677 cx.platform.stop_display_link(display_id);
678 }
679 })
680 .ok();
681 }
682 });
683 e.insert(consumer_task);
684 }
685 debug_assert!(self.app.frame_consumers.is_empty());
686 self.app.frame_consumers = frame_consumers;
687
688 if self.next_frame_callbacks.is_empty() {
689 self.platform.start_display_link(display_id);
690 }
691
692 self.next_frame_callbacks
693 .entry(display_id)
694 .or_default()
695 .push(Box::new(move |cx: &mut AppContext| {
696 cx.update_window(handle, |_root_view, cx| callback(cx)).ok();
697 }));
698 }
699
700 /// Spawn the future returned by the given closure on the application thread pool.
701 /// The closure is provided a handle to the current window and an `AsyncWindowContext` for
702 /// use within your future.
703 pub fn spawn<Fut, R>(&mut self, f: impl FnOnce(AsyncWindowContext) -> Fut) -> Task<R>
704 where
705 R: 'static,
706 Fut: Future<Output = R> + 'static,
707 {
708 self.app
709 .spawn(|app| f(AsyncWindowContext::new(app, self.window.handle)))
710 }
711
712 /// Update the global of the given type. The given closure is given simultaneous mutable
713 /// access both to the global and the context.
714 pub fn update_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
715 where
716 G: 'static,
717 {
718 let mut global = self.app.lease_global::<G>();
719 let result = f(&mut global, self);
720 self.app.end_global_lease(global);
721 result
722 }
723
724 #[must_use]
725 /// Add a node to the layout tree for the current frame. Takes the `Style` of the element for which
726 /// layout is being requested, along with the layout ids of any children. This method is called during
727 /// calls to the `Element::layout` trait method and enables any element to participate in layout.
728 pub fn request_layout(
729 &mut self,
730 style: &Style,
731 children: impl IntoIterator<Item = LayoutId>,
732 ) -> LayoutId {
733 self.app.layout_id_buffer.clear();
734 self.app.layout_id_buffer.extend(children);
735 let rem_size = self.rem_size();
736
737 self.window.layout_engine.as_mut().unwrap().request_layout(
738 style,
739 rem_size,
740 &self.app.layout_id_buffer,
741 )
742 }
743
744 /// Add a node to the layout tree for the current frame. Instead of taking a `Style` and children,
745 /// this variant takes a function that is invoked during layout so you can use arbitrary logic to
746 /// determine the element's size. One place this is used internally is when measuring text.
747 ///
748 /// The given closure is invoked at layout time with the known dimensions and available space and
749 /// returns a `Size`.
750 pub fn request_measured_layout<
751 F: FnMut(Size<Option<Pixels>>, Size<AvailableSpace>, &mut WindowContext) -> Size<Pixels>
752 + 'static,
753 >(
754 &mut self,
755 style: Style,
756 measure: F,
757 ) -> LayoutId {
758 let rem_size = self.rem_size();
759 self.window
760 .layout_engine
761 .as_mut()
762 .unwrap()
763 .request_measured_layout(style, rem_size, measure)
764 }
765
766 pub fn layout_style(&self, layout_id: LayoutId) -> Option<&Style> {
767 self.window
768 .layout_engine
769 .as_ref()
770 .unwrap()
771 .requested_style(layout_id)
772 }
773
774 pub fn compute_layout(&mut self, layout_id: LayoutId, available_space: Size<AvailableSpace>) {
775 let mut layout_engine = self.window.layout_engine.take().unwrap();
776 layout_engine.compute_layout(layout_id, available_space, self);
777 self.window.layout_engine = Some(layout_engine);
778 }
779
780 /// Obtain the bounds computed for the given LayoutId relative to the window. This method should not
781 /// be invoked until the paint phase begins, and will usually be invoked by GPUI itself automatically
782 /// in order to pass your element its `Bounds` automatically.
783 pub fn layout_bounds(&mut self, layout_id: LayoutId) -> Bounds<Pixels> {
784 let mut bounds = self
785 .window
786 .layout_engine
787 .as_mut()
788 .unwrap()
789 .layout_bounds(layout_id)
790 .map(Into::into);
791 bounds.origin += self.element_offset();
792 bounds
793 }
794
795 fn window_bounds_changed(&mut self) {
796 self.window.scale_factor = self.window.platform_window.scale_factor();
797 self.window.viewport_size = self.window.platform_window.content_size();
798 self.window.bounds = self.window.platform_window.bounds();
799 self.window.display_id = self.window.platform_window.display().id();
800 self.notify();
801
802 self.window
803 .bounds_observers
804 .clone()
805 .retain(&(), |callback| callback(self));
806 }
807
808 pub fn window_bounds(&self) -> WindowBounds {
809 self.window.bounds
810 }
811
812 pub fn viewport_size(&self) -> Size<Pixels> {
813 self.window.viewport_size
814 }
815
816 pub fn is_window_active(&self) -> bool {
817 self.window.active
818 }
819
820 pub fn zoom_window(&self) {
821 self.window.platform_window.zoom();
822 }
823
824 pub fn set_window_title(&mut self, title: &str) {
825 self.window.platform_window.set_title(title);
826 }
827
828 pub fn set_window_edited(&mut self, edited: bool) {
829 self.window.platform_window.set_edited(edited);
830 }
831
832 pub fn display(&self) -> Option<Rc<dyn PlatformDisplay>> {
833 self.platform
834 .displays()
835 .into_iter()
836 .find(|display| display.id() == self.window.display_id)
837 }
838
839 pub fn show_character_palette(&self) {
840 self.window.platform_window.show_character_palette();
841 }
842
843 /// The scale factor of the display associated with the window. For example, it could
844 /// return 2.0 for a "retina" display, indicating that each logical pixel should actually
845 /// be rendered as two pixels on screen.
846 pub fn scale_factor(&self) -> f32 {
847 self.window.scale_factor
848 }
849
850 /// The size of an em for the base font of the application. Adjusting this value allows the
851 /// UI to scale, just like zooming a web page.
852 pub fn rem_size(&self) -> Pixels {
853 self.window.rem_size
854 }
855
856 /// Sets the size of an em for the base font of the application. Adjusting this value allows the
857 /// UI to scale, just like zooming a web page.
858 pub fn set_rem_size(&mut self, rem_size: impl Into<Pixels>) {
859 self.window.rem_size = rem_size.into();
860 }
861
862 /// The line height associated with the current text style.
863 pub fn line_height(&self) -> Pixels {
864 let rem_size = self.rem_size();
865 let text_style = self.text_style();
866 text_style
867 .line_height
868 .to_pixels(text_style.font_size, rem_size)
869 }
870
871 /// Call to prevent the default action of an event. Currently only used to prevent
872 /// parent elements from becoming focused on mouse down.
873 pub fn prevent_default(&mut self) {
874 self.window.default_prevented = true;
875 }
876
877 /// Obtain whether default has been prevented for the event currently being dispatched.
878 pub fn default_prevented(&self) -> bool {
879 self.window.default_prevented
880 }
881
882 /// Register a mouse event listener on the window for the next frame. The type of event
883 /// is determined by the first parameter of the given listener. When the next frame is rendered
884 /// the listener will be cleared.
885 pub fn on_mouse_event<Event: 'static>(
886 &mut self,
887 mut handler: impl FnMut(&Event, DispatchPhase, &mut WindowContext) + 'static,
888 ) {
889 let order = self.window.next_frame.z_index_stack.clone();
890 let view_id = *self.window.next_frame.view_stack.last().unwrap();
891 self.window
892 .next_frame
893 .mouse_listeners
894 .entry(TypeId::of::<Event>())
895 .or_default()
896 .push((
897 order,
898 view_id,
899 Box::new(
900 move |event: &dyn Any, phase: DispatchPhase, cx: &mut WindowContext<'_>| {
901 handler(event.downcast_ref().unwrap(), phase, cx)
902 },
903 ),
904 ))
905 }
906
907 /// Register a key event listener on the window for the next frame. The type of event
908 /// is determined by the first parameter of the given listener. When the next frame is rendered
909 /// the listener will be cleared.
910 ///
911 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
912 /// a specific need to register a global listener.
913 pub fn on_key_event<Event: 'static>(
914 &mut self,
915 listener: impl Fn(&Event, DispatchPhase, &mut WindowContext) + 'static,
916 ) {
917 self.window.next_frame.dispatch_tree.on_key_event(Rc::new(
918 move |event: &dyn Any, phase, cx: &mut WindowContext<'_>| {
919 if let Some(event) = event.downcast_ref::<Event>() {
920 listener(event, phase, cx)
921 }
922 },
923 ));
924 }
925
926 /// Register an action listener on the window for the next frame. The type of action
927 /// is determined by the first parameter of the given listener. When the next frame is rendered
928 /// the listener will be cleared.
929 ///
930 /// This is a fairly low-level method, so prefer using action handlers on elements unless you have
931 /// a specific need to register a global listener.
932 pub fn on_action(
933 &mut self,
934 action_type: TypeId,
935 listener: impl Fn(&dyn Any, DispatchPhase, &mut WindowContext) + 'static,
936 ) {
937 self.window
938 .next_frame
939 .dispatch_tree
940 .on_action(action_type, Rc::new(listener));
941 }
942
943 pub fn is_action_available(&self, action: &dyn Action) -> bool {
944 let target = self
945 .focused()
946 .and_then(|focused_handle| {
947 self.window
948 .rendered_frame
949 .dispatch_tree
950 .focusable_node_id(focused_handle.id)
951 })
952 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
953 self.window
954 .rendered_frame
955 .dispatch_tree
956 .is_action_available(action, target)
957 }
958
959 /// The position of the mouse relative to the window.
960 pub fn mouse_position(&self) -> Point<Pixels> {
961 self.window.mouse_position
962 }
963
964 /// The current state of the keyboard's modifiers
965 pub fn modifiers(&self) -> Modifiers {
966 self.window.modifiers
967 }
968
969 pub fn set_cursor_style(&mut self, style: CursorStyle) {
970 self.window.requested_cursor_style = Some(style)
971 }
972
973 /// Called during painting to track which z-index is on top at each pixel position
974 pub fn add_opaque_layer(&mut self, bounds: Bounds<Pixels>) {
975 let stacking_order = self.window.next_frame.z_index_stack.clone();
976 let depth_map = &mut self.window.next_frame.depth_map;
977 match depth_map.binary_search_by(|(level, _)| stacking_order.cmp(level)) {
978 Ok(i) | Err(i) => depth_map.insert(i, (stacking_order, bounds)),
979 }
980 }
981
982 /// Returns true if there is no opaque layer containing the given point
983 /// on top of the given level. Layers whose level is an extension of the
984 /// level are not considered to be on top of the level.
985 pub fn was_top_layer(&self, point: &Point<Pixels>, level: &StackingOrder) -> bool {
986 for (opaque_level, bounds) in self.window.rendered_frame.depth_map.iter() {
987 if level >= opaque_level {
988 break;
989 }
990
991 if bounds.contains(point) && !opaque_level.starts_with(level) {
992 return false;
993 }
994 }
995 true
996 }
997
998 pub fn was_top_layer_under_active_drag(
999 &self,
1000 point: &Point<Pixels>,
1001 level: &StackingOrder,
1002 ) -> bool {
1003 for (opaque_level, bounds) in self.window.rendered_frame.depth_map.iter() {
1004 if level >= opaque_level {
1005 break;
1006 }
1007 if opaque_level.starts_with(&[ACTIVE_DRAG_Z_INDEX]) {
1008 continue;
1009 }
1010
1011 if bounds.contains(point) && !opaque_level.starts_with(level) {
1012 return false;
1013 }
1014 }
1015 true
1016 }
1017
1018 /// Called during painting to get the current stacking order.
1019 pub fn stacking_order(&self) -> &StackingOrder {
1020 &self.window.next_frame.z_index_stack
1021 }
1022
1023 /// Paint one or more drop shadows into the scene for the next frame at the current z-index.
1024 pub fn paint_shadows(
1025 &mut self,
1026 bounds: Bounds<Pixels>,
1027 corner_radii: Corners<Pixels>,
1028 shadows: &[BoxShadow],
1029 ) {
1030 let scale_factor = self.scale_factor();
1031 let content_mask = self.content_mask();
1032 let window = &mut *self.window;
1033 for shadow in shadows {
1034 let mut shadow_bounds = bounds;
1035 shadow_bounds.origin += shadow.offset;
1036 shadow_bounds.dilate(shadow.spread_radius);
1037 window.next_frame.scene_builder.insert(
1038 &window.next_frame.z_index_stack,
1039 Shadow {
1040 order: 0,
1041 bounds: shadow_bounds.scale(scale_factor),
1042 content_mask: content_mask.scale(scale_factor),
1043 corner_radii: corner_radii.scale(scale_factor),
1044 color: shadow.color,
1045 blur_radius: shadow.blur_radius.scale(scale_factor),
1046 },
1047 );
1048 }
1049 }
1050
1051 /// Paint one or more quads into the scene for the next frame at the current stacking context.
1052 /// Quads are colored rectangular regions with an optional background, border, and corner radius.
1053 /// see [`fill`], [`outline`], and [`quad`] to construct this type.
1054 pub fn paint_quad(&mut self, quad: PaintQuad) {
1055 let scale_factor = self.scale_factor();
1056 let content_mask = self.content_mask();
1057
1058 let window = &mut *self.window;
1059 window.next_frame.scene_builder.insert(
1060 &window.next_frame.z_index_stack,
1061 Quad {
1062 order: 0,
1063 bounds: quad.bounds.scale(scale_factor),
1064 content_mask: content_mask.scale(scale_factor),
1065 background: quad.background,
1066 border_color: quad.border_color,
1067 corner_radii: quad.corner_radii.scale(scale_factor),
1068 border_widths: quad.border_widths.scale(scale_factor),
1069 },
1070 );
1071 }
1072
1073 /// Paint the given `Path` into the scene for the next frame at the current z-index.
1074 pub fn paint_path(&mut self, mut path: Path<Pixels>, color: impl Into<Hsla>) {
1075 let scale_factor = self.scale_factor();
1076 let content_mask = self.content_mask();
1077 path.content_mask = content_mask;
1078 path.color = color.into();
1079 let window = &mut *self.window;
1080 window
1081 .next_frame
1082 .scene_builder
1083 .insert(&window.next_frame.z_index_stack, path.scale(scale_factor));
1084 }
1085
1086 /// Paint an underline into the scene for the next frame at the current z-index.
1087 pub fn paint_underline(
1088 &mut self,
1089 origin: Point<Pixels>,
1090 width: Pixels,
1091 style: &UnderlineStyle,
1092 ) {
1093 let scale_factor = self.scale_factor();
1094 let height = if style.wavy {
1095 style.thickness * 3.
1096 } else {
1097 style.thickness
1098 };
1099 let bounds = Bounds {
1100 origin,
1101 size: size(width, height),
1102 };
1103 let content_mask = self.content_mask();
1104 let window = &mut *self.window;
1105 window.next_frame.scene_builder.insert(
1106 &window.next_frame.z_index_stack,
1107 Underline {
1108 order: 0,
1109 bounds: bounds.scale(scale_factor),
1110 content_mask: content_mask.scale(scale_factor),
1111 thickness: style.thickness.scale(scale_factor),
1112 color: style.color.unwrap_or_default(),
1113 wavy: style.wavy,
1114 },
1115 );
1116 }
1117
1118 /// Paint a monochrome (non-emoji) glyph into the scene for the next frame at the current z-index.
1119 /// The y component of the origin is the baseline of the glyph.
1120 pub fn paint_glyph(
1121 &mut self,
1122 origin: Point<Pixels>,
1123 font_id: FontId,
1124 glyph_id: GlyphId,
1125 font_size: Pixels,
1126 color: Hsla,
1127 ) -> Result<()> {
1128 let scale_factor = self.scale_factor();
1129 let glyph_origin = origin.scale(scale_factor);
1130 let subpixel_variant = Point {
1131 x: (glyph_origin.x.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
1132 y: (glyph_origin.y.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
1133 };
1134 let params = RenderGlyphParams {
1135 font_id,
1136 glyph_id,
1137 font_size,
1138 subpixel_variant,
1139 scale_factor,
1140 is_emoji: false,
1141 };
1142
1143 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
1144 if !raster_bounds.is_zero() {
1145 let tile =
1146 self.window
1147 .sprite_atlas
1148 .get_or_insert_with(¶ms.clone().into(), &mut || {
1149 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
1150 Ok((size, Cow::Owned(bytes)))
1151 })?;
1152 let bounds = Bounds {
1153 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
1154 size: tile.bounds.size.map(Into::into),
1155 };
1156 let content_mask = self.content_mask().scale(scale_factor);
1157 let window = &mut *self.window;
1158 window.next_frame.scene_builder.insert(
1159 &window.next_frame.z_index_stack,
1160 MonochromeSprite {
1161 order: 0,
1162 bounds,
1163 content_mask,
1164 color,
1165 tile,
1166 },
1167 );
1168 }
1169 Ok(())
1170 }
1171
1172 /// Paint an emoji glyph into the scene for the next frame at the current z-index.
1173 /// The y component of the origin is the baseline of the glyph.
1174 pub fn paint_emoji(
1175 &mut self,
1176 origin: Point<Pixels>,
1177 font_id: FontId,
1178 glyph_id: GlyphId,
1179 font_size: Pixels,
1180 ) -> Result<()> {
1181 let scale_factor = self.scale_factor();
1182 let glyph_origin = origin.scale(scale_factor);
1183 let params = RenderGlyphParams {
1184 font_id,
1185 glyph_id,
1186 font_size,
1187 // We don't render emojis with subpixel variants.
1188 subpixel_variant: Default::default(),
1189 scale_factor,
1190 is_emoji: true,
1191 };
1192
1193 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
1194 if !raster_bounds.is_zero() {
1195 let tile =
1196 self.window
1197 .sprite_atlas
1198 .get_or_insert_with(¶ms.clone().into(), &mut || {
1199 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
1200 Ok((size, Cow::Owned(bytes)))
1201 })?;
1202 let bounds = Bounds {
1203 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
1204 size: tile.bounds.size.map(Into::into),
1205 };
1206 let content_mask = self.content_mask().scale(scale_factor);
1207 let window = &mut *self.window;
1208
1209 window.next_frame.scene_builder.insert(
1210 &window.next_frame.z_index_stack,
1211 PolychromeSprite {
1212 order: 0,
1213 bounds,
1214 corner_radii: Default::default(),
1215 content_mask,
1216 tile,
1217 grayscale: false,
1218 },
1219 );
1220 }
1221 Ok(())
1222 }
1223
1224 /// Paint a monochrome SVG into the scene for the next frame at the current stacking context.
1225 pub fn paint_svg(
1226 &mut self,
1227 bounds: Bounds<Pixels>,
1228 path: SharedString,
1229 color: Hsla,
1230 ) -> Result<()> {
1231 let scale_factor = self.scale_factor();
1232 let bounds = bounds.scale(scale_factor);
1233 // Render the SVG at twice the size to get a higher quality result.
1234 let params = RenderSvgParams {
1235 path,
1236 size: bounds
1237 .size
1238 .map(|pixels| DevicePixels::from((pixels.0 * 2.).ceil() as i32)),
1239 };
1240
1241 let tile =
1242 self.window
1243 .sprite_atlas
1244 .get_or_insert_with(¶ms.clone().into(), &mut || {
1245 let bytes = self.svg_renderer.render(¶ms)?;
1246 Ok((params.size, Cow::Owned(bytes)))
1247 })?;
1248 let content_mask = self.content_mask().scale(scale_factor);
1249
1250 let window = &mut *self.window;
1251 window.next_frame.scene_builder.insert(
1252 &window.next_frame.z_index_stack,
1253 MonochromeSprite {
1254 order: 0,
1255 bounds,
1256 content_mask,
1257 color,
1258 tile,
1259 },
1260 );
1261
1262 Ok(())
1263 }
1264
1265 /// Paint an image into the scene for the next frame at the current z-index.
1266 pub fn paint_image(
1267 &mut self,
1268 bounds: Bounds<Pixels>,
1269 corner_radii: Corners<Pixels>,
1270 data: Arc<ImageData>,
1271 grayscale: bool,
1272 ) -> Result<()> {
1273 let scale_factor = self.scale_factor();
1274 let bounds = bounds.scale(scale_factor);
1275 let params = RenderImageParams { image_id: data.id };
1276
1277 let tile = self
1278 .window
1279 .sprite_atlas
1280 .get_or_insert_with(¶ms.clone().into(), &mut || {
1281 Ok((data.size(), Cow::Borrowed(data.as_bytes())))
1282 })?;
1283 let content_mask = self.content_mask().scale(scale_factor);
1284 let corner_radii = corner_radii.scale(scale_factor);
1285
1286 let window = &mut *self.window;
1287 window.next_frame.scene_builder.insert(
1288 &window.next_frame.z_index_stack,
1289 PolychromeSprite {
1290 order: 0,
1291 bounds,
1292 content_mask,
1293 corner_radii,
1294 tile,
1295 grayscale,
1296 },
1297 );
1298 Ok(())
1299 }
1300
1301 /// Paint a surface into the scene for the next frame at the current z-index.
1302 pub fn paint_surface(&mut self, bounds: Bounds<Pixels>, image_buffer: CVImageBuffer) {
1303 let scale_factor = self.scale_factor();
1304 let bounds = bounds.scale(scale_factor);
1305 let content_mask = self.content_mask().scale(scale_factor);
1306 let window = &mut *self.window;
1307 window.next_frame.scene_builder.insert(
1308 &window.next_frame.z_index_stack,
1309 Surface {
1310 order: 0,
1311 bounds,
1312 content_mask,
1313 image_buffer,
1314 },
1315 );
1316 }
1317
1318 pub(crate) fn reuse_geometry(&mut self) {
1319 let window = &mut self.window;
1320 let view_id = *window.next_frame.view_stack.last().unwrap();
1321 assert!(window.next_frame.reused_views.insert(view_id));
1322 window
1323 .next_frame
1324 .dispatch_tree
1325 .graft(view_id, &mut window.rendered_frame.dispatch_tree)
1326 }
1327
1328 /// Draw pixels to the display for this window based on the contents of its scene.
1329 pub(crate) fn draw(&mut self) -> Scene {
1330 println!("=====================");
1331 self.window.dirty = false;
1332 self.window.drawing = true;
1333
1334 #[cfg(any(test, feature = "test-support"))]
1335 {
1336 self.window.focus_invalidated = false;
1337 }
1338
1339 self.text_system().start_frame();
1340 self.window.platform_window.clear_input_handler();
1341 self.window.layout_engine.as_mut().unwrap().clear();
1342 self.window.next_frame.clear();
1343 let root_view = self.window.root_view.take().unwrap();
1344
1345 self.with_z_index(0, |cx| {
1346 cx.with_key_dispatch(Some(KeyContext::default()), None, |_, cx| {
1347 for (action_type, action_listeners) in &cx.app.global_action_listeners {
1348 for action_listener in action_listeners.iter().cloned() {
1349 cx.window.next_frame.dispatch_tree.on_action(
1350 *action_type,
1351 Rc::new(move |action: &dyn Any, phase, cx: &mut WindowContext<'_>| {
1352 action_listener(action, phase, cx)
1353 }),
1354 )
1355 }
1356 }
1357
1358 let available_space = cx.window.viewport_size.map(Into::into);
1359 root_view.draw(Point::default(), available_space, cx);
1360 })
1361 });
1362
1363 if let Some(active_drag) = self.app.active_drag.take() {
1364 self.with_z_index(ACTIVE_DRAG_Z_INDEX, |cx| {
1365 let offset = cx.mouse_position() - active_drag.cursor_offset;
1366 let available_space = size(AvailableSpace::MinContent, AvailableSpace::MinContent);
1367 active_drag.view.draw(offset, available_space, cx);
1368 });
1369 self.active_drag = Some(active_drag);
1370 } else if let Some(active_tooltip) = self.app.active_tooltip.take() {
1371 self.with_z_index(1, |cx| {
1372 let available_space = size(AvailableSpace::MinContent, AvailableSpace::MinContent);
1373 active_tooltip
1374 .view
1375 .draw(active_tooltip.cursor_offset, available_space, cx);
1376 });
1377 }
1378
1379 self.window
1380 .next_frame
1381 .dispatch_tree
1382 .preserve_pending_keystrokes(
1383 &mut self.window.rendered_frame.dispatch_tree,
1384 self.window.focus,
1385 );
1386 self.window.next_frame.focus = self.window.focus;
1387 self.window.root_view = Some(root_view);
1388 for (type_id, listeners) in &mut self.window.rendered_frame.mouse_listeners {
1389 let next_listeners = self
1390 .window
1391 .next_frame
1392 .mouse_listeners
1393 .entry(*type_id)
1394 .or_default();
1395 for (order, view_id, listener) in listeners.drain(..) {
1396 if self.window.next_frame.reused_views.contains(&view_id) {
1397 next_listeners.push((order, view_id, listener));
1398 }
1399 }
1400 }
1401
1402 let previous_focus_path = self.window.rendered_frame.focus_path();
1403 mem::swap(&mut self.window.rendered_frame, &mut self.window.next_frame);
1404 let current_focus_path = self.window.rendered_frame.focus_path();
1405
1406 if previous_focus_path != current_focus_path {
1407 if !previous_focus_path.is_empty() && current_focus_path.is_empty() {
1408 self.window
1409 .blur_listeners
1410 .clone()
1411 .retain(&(), |listener| listener(self));
1412 }
1413
1414 let event = FocusEvent {
1415 previous_focus_path,
1416 current_focus_path,
1417 };
1418 self.window
1419 .focus_listeners
1420 .clone()
1421 .retain(&(), |listener| listener(&event, self));
1422 }
1423
1424 let scene = self.window.rendered_frame.scene_builder.build();
1425
1426 // Set the cursor only if we're the active window.
1427 let cursor_style = self
1428 .window
1429 .requested_cursor_style
1430 .take()
1431 .unwrap_or(CursorStyle::Arrow);
1432 if self.is_window_active() {
1433 self.platform.set_cursor_style(cursor_style);
1434 }
1435
1436 self.window.drawing = false;
1437 self.window.dirty_views.clear();
1438 ELEMENT_ARENA.with_borrow_mut(|element_arena| element_arena.clear());
1439
1440 scene
1441 }
1442
1443 /// Dispatch a mouse or keyboard event on the window.
1444 pub fn dispatch_event(&mut self, event: InputEvent) -> bool {
1445 // Handlers may set this to false by calling `stop_propagation`.
1446 self.app.propagate_event = true;
1447 // Handlers may set this to true by calling `prevent_default`.
1448 self.window.default_prevented = false;
1449
1450 let event = match event {
1451 // Track the mouse position with our own state, since accessing the platform
1452 // API for the mouse position can only occur on the main thread.
1453 InputEvent::MouseMove(mouse_move) => {
1454 self.window.mouse_position = mouse_move.position;
1455 self.window.modifiers = mouse_move.modifiers;
1456 InputEvent::MouseMove(mouse_move)
1457 }
1458 InputEvent::MouseDown(mouse_down) => {
1459 self.window.mouse_position = mouse_down.position;
1460 self.window.modifiers = mouse_down.modifiers;
1461 InputEvent::MouseDown(mouse_down)
1462 }
1463 InputEvent::MouseUp(mouse_up) => {
1464 self.window.mouse_position = mouse_up.position;
1465 self.window.modifiers = mouse_up.modifiers;
1466 InputEvent::MouseUp(mouse_up)
1467 }
1468 InputEvent::MouseExited(mouse_exited) => {
1469 // todo!("Should we record that the mouse is outside of the window somehow? Or are these global pixels?")
1470 self.window.modifiers = mouse_exited.modifiers;
1471
1472 InputEvent::MouseExited(mouse_exited)
1473 }
1474 InputEvent::ModifiersChanged(modifiers_changed) => {
1475 self.window.modifiers = modifiers_changed.modifiers;
1476 InputEvent::ModifiersChanged(modifiers_changed)
1477 }
1478 InputEvent::ScrollWheel(scroll_wheel) => {
1479 self.window.mouse_position = scroll_wheel.position;
1480 self.window.modifiers = scroll_wheel.modifiers;
1481 InputEvent::ScrollWheel(scroll_wheel)
1482 }
1483 // Translate dragging and dropping of external files from the operating system
1484 // to internal drag and drop events.
1485 InputEvent::FileDrop(file_drop) => match file_drop {
1486 FileDropEvent::Entered { position, paths } => {
1487 self.window.mouse_position = position;
1488 if self.active_drag.is_none() {
1489 self.active_drag = Some(AnyDrag {
1490 value: Box::new(paths.clone()),
1491 view: self.new_view(|_| paths).into(),
1492 cursor_offset: position,
1493 });
1494 }
1495 InputEvent::MouseMove(MouseMoveEvent {
1496 position,
1497 pressed_button: Some(MouseButton::Left),
1498 modifiers: Modifiers::default(),
1499 })
1500 }
1501 FileDropEvent::Pending { position } => {
1502 self.window.mouse_position = position;
1503 InputEvent::MouseMove(MouseMoveEvent {
1504 position,
1505 pressed_button: Some(MouseButton::Left),
1506 modifiers: Modifiers::default(),
1507 })
1508 }
1509 FileDropEvent::Submit { position } => {
1510 self.activate(true);
1511 self.window.mouse_position = position;
1512 InputEvent::MouseUp(MouseUpEvent {
1513 button: MouseButton::Left,
1514 position,
1515 modifiers: Modifiers::default(),
1516 click_count: 1,
1517 })
1518 }
1519 FileDropEvent::Exited => InputEvent::MouseUp(MouseUpEvent {
1520 button: MouseButton::Left,
1521 position: Point::default(),
1522 modifiers: Modifiers::default(),
1523 click_count: 1,
1524 }),
1525 },
1526 InputEvent::KeyDown(_) | InputEvent::KeyUp(_) => event,
1527 };
1528
1529 if let Some(any_mouse_event) = event.mouse_event() {
1530 self.dispatch_mouse_event(any_mouse_event);
1531 } else if let Some(any_key_event) = event.keyboard_event() {
1532 self.dispatch_key_event(any_key_event);
1533 }
1534
1535 !self.app.propagate_event
1536 }
1537
1538 fn dispatch_mouse_event(&mut self, event: &dyn Any) {
1539 if let Some(mut handlers) = self
1540 .window
1541 .rendered_frame
1542 .mouse_listeners
1543 .remove(&event.type_id())
1544 {
1545 // Because handlers may add other handlers, we sort every time.
1546 handlers.sort_by(|(a, _, _), (b, _, _)| a.cmp(b));
1547
1548 // Capture phase, events bubble from back to front. Handlers for this phase are used for
1549 // special purposes, such as detecting events outside of a given Bounds.
1550 for (_, _, handler) in &mut handlers {
1551 handler(event, DispatchPhase::Capture, self);
1552 if !self.app.propagate_event {
1553 break;
1554 }
1555 }
1556
1557 // Bubble phase, where most normal handlers do their work.
1558 if self.app.propagate_event {
1559 for (_, _, handler) in handlers.iter_mut().rev() {
1560 handler(event, DispatchPhase::Bubble, self);
1561 if !self.app.propagate_event {
1562 break;
1563 }
1564 }
1565 }
1566
1567 self.window
1568 .rendered_frame
1569 .mouse_listeners
1570 .insert(event.type_id(), handlers);
1571 }
1572
1573 if self.app.propagate_event && self.has_active_drag() {
1574 if event.is::<MouseMoveEvent>() {
1575 // If this was a mouse move event, redraw the window so that the
1576 // active drag can follow the mouse cursor.
1577 self.notify();
1578 } else if event.is::<MouseUpEvent>() {
1579 // If this was a mouse up event, cancel the active drag and redraw
1580 // the window.
1581 self.active_drag = None;
1582 self.notify();
1583 }
1584 }
1585 }
1586
1587 fn dispatch_key_event(&mut self, event: &dyn Any) {
1588 let node_id = self
1589 .window
1590 .focus
1591 .and_then(|focus_id| {
1592 self.window
1593 .rendered_frame
1594 .dispatch_tree
1595 .focusable_node_id(focus_id)
1596 })
1597 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
1598
1599 let dispatch_path = self
1600 .window
1601 .rendered_frame
1602 .dispatch_tree
1603 .dispatch_path(node_id);
1604
1605 let mut actions: Vec<Box<dyn Action>> = Vec::new();
1606
1607 let mut context_stack: SmallVec<[KeyContext; 16]> = SmallVec::new();
1608 for node_id in &dispatch_path {
1609 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1610
1611 if let Some(context) = node.context.clone() {
1612 context_stack.push(context);
1613 }
1614 }
1615
1616 for node_id in dispatch_path.iter().rev() {
1617 // Match keystrokes
1618 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1619 if node.context.is_some() {
1620 if let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() {
1621 let mut new_actions = self
1622 .window
1623 .rendered_frame
1624 .dispatch_tree
1625 .dispatch_key(&key_down_event.keystroke, &context_stack);
1626 actions.append(&mut new_actions);
1627 }
1628
1629 context_stack.pop();
1630 }
1631 }
1632
1633 if !actions.is_empty() {
1634 self.clear_pending_keystrokes();
1635 }
1636
1637 self.propagate_event = true;
1638 for action in actions {
1639 self.dispatch_action_on_node(node_id, action.boxed_clone());
1640 if !self.propagate_event {
1641 self.dispatch_keystroke_observers(event, Some(action));
1642 return;
1643 }
1644 }
1645
1646 // Capture phase
1647 for node_id in &dispatch_path {
1648 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1649
1650 for key_listener in node.key_listeners.clone() {
1651 key_listener(event, DispatchPhase::Capture, self);
1652 if !self.propagate_event {
1653 return;
1654 }
1655 }
1656 }
1657
1658 // Bubble phase
1659 for node_id in dispatch_path.iter().rev() {
1660 // Handle low level key events
1661 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1662 for key_listener in node.key_listeners.clone() {
1663 key_listener(event, DispatchPhase::Bubble, self);
1664 if !self.propagate_event {
1665 return;
1666 }
1667 }
1668 }
1669
1670 self.dispatch_keystroke_observers(event, None);
1671 }
1672
1673 pub fn has_pending_keystrokes(&self) -> bool {
1674 self.window
1675 .rendered_frame
1676 .dispatch_tree
1677 .has_pending_keystrokes()
1678 }
1679
1680 fn dispatch_action_on_node(&mut self, node_id: DispatchNodeId, action: Box<dyn Action>) {
1681 let dispatch_path = self
1682 .window
1683 .rendered_frame
1684 .dispatch_tree
1685 .dispatch_path(node_id);
1686
1687 // Capture phase
1688 for node_id in &dispatch_path {
1689 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1690 for DispatchActionListener {
1691 action_type,
1692 listener,
1693 } in node.action_listeners.clone()
1694 {
1695 let any_action = action.as_any();
1696 if action_type == any_action.type_id() {
1697 listener(any_action, DispatchPhase::Capture, self);
1698 if !self.propagate_event {
1699 return;
1700 }
1701 }
1702 }
1703 }
1704 // Bubble phase
1705 for node_id in dispatch_path.iter().rev() {
1706 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1707 for DispatchActionListener {
1708 action_type,
1709 listener,
1710 } in node.action_listeners.clone()
1711 {
1712 let any_action = action.as_any();
1713 if action_type == any_action.type_id() {
1714 self.propagate_event = false; // Actions stop propagation by default during the bubble phase
1715 listener(any_action, DispatchPhase::Bubble, self);
1716 if !self.propagate_event {
1717 return;
1718 }
1719 }
1720 }
1721 }
1722 }
1723
1724 /// Register the given handler to be invoked whenever the global of the given type
1725 /// is updated.
1726 pub fn observe_global<G: 'static>(
1727 &mut self,
1728 f: impl Fn(&mut WindowContext<'_>) + 'static,
1729 ) -> Subscription {
1730 let window_handle = self.window.handle;
1731 let (subscription, activate) = self.global_observers.insert(
1732 TypeId::of::<G>(),
1733 Box::new(move |cx| window_handle.update(cx, |_, cx| f(cx)).is_ok()),
1734 );
1735 self.app.defer(move |_| activate());
1736 subscription
1737 }
1738
1739 pub fn activate_window(&self) {
1740 self.window.platform_window.activate();
1741 }
1742
1743 pub fn minimize_window(&self) {
1744 self.window.platform_window.minimize();
1745 }
1746
1747 pub fn toggle_full_screen(&self) {
1748 self.window.platform_window.toggle_full_screen();
1749 }
1750
1751 pub fn prompt(
1752 &self,
1753 level: PromptLevel,
1754 msg: &str,
1755 answers: &[&str],
1756 ) -> oneshot::Receiver<usize> {
1757 self.window.platform_window.prompt(level, msg, answers)
1758 }
1759
1760 pub fn available_actions(&self) -> Vec<Box<dyn Action>> {
1761 let node_id = self
1762 .window
1763 .focus
1764 .and_then(|focus_id| {
1765 self.window
1766 .rendered_frame
1767 .dispatch_tree
1768 .focusable_node_id(focus_id)
1769 })
1770 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
1771
1772 self.window
1773 .rendered_frame
1774 .dispatch_tree
1775 .available_actions(node_id)
1776 }
1777
1778 pub fn bindings_for_action(&self, action: &dyn Action) -> Vec<KeyBinding> {
1779 self.window
1780 .rendered_frame
1781 .dispatch_tree
1782 .bindings_for_action(
1783 action,
1784 &self.window.rendered_frame.dispatch_tree.context_stack,
1785 )
1786 }
1787
1788 pub fn bindings_for_action_in(
1789 &self,
1790 action: &dyn Action,
1791 focus_handle: &FocusHandle,
1792 ) -> Vec<KeyBinding> {
1793 let dispatch_tree = &self.window.rendered_frame.dispatch_tree;
1794
1795 let Some(node_id) = dispatch_tree.focusable_node_id(focus_handle.id) else {
1796 return vec![];
1797 };
1798 let context_stack = dispatch_tree
1799 .dispatch_path(node_id)
1800 .into_iter()
1801 .filter_map(|node_id| dispatch_tree.node(node_id).context.clone())
1802 .collect();
1803 dispatch_tree.bindings_for_action(action, &context_stack)
1804 }
1805
1806 pub fn listener_for<V: Render, E>(
1807 &self,
1808 view: &View<V>,
1809 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
1810 ) -> impl Fn(&E, &mut WindowContext) + 'static {
1811 let view = view.downgrade();
1812 move |e: &E, cx: &mut WindowContext| {
1813 view.update(cx, |view, cx| f(view, e, cx)).ok();
1814 }
1815 }
1816
1817 pub fn handler_for<V: Render>(
1818 &self,
1819 view: &View<V>,
1820 f: impl Fn(&mut V, &mut ViewContext<V>) + 'static,
1821 ) -> impl Fn(&mut WindowContext) {
1822 let view = view.downgrade();
1823 move |cx: &mut WindowContext| {
1824 view.update(cx, |view, cx| f(view, cx)).ok();
1825 }
1826 }
1827
1828 //========== ELEMENT RELATED FUNCTIONS ===========
1829 pub fn with_key_dispatch<R>(
1830 &mut self,
1831 context: Option<KeyContext>,
1832 focus_handle: Option<FocusHandle>,
1833 f: impl FnOnce(Option<FocusHandle>, &mut Self) -> R,
1834 ) -> R {
1835 let window = &mut self.window;
1836 window.next_frame.dispatch_tree.push_node(context.clone());
1837 if let Some(focus_handle) = focus_handle.as_ref() {
1838 window
1839 .next_frame
1840 .dispatch_tree
1841 .make_focusable(focus_handle.id);
1842 }
1843 let result = f(focus_handle, self);
1844
1845 self.window.next_frame.dispatch_tree.pop_node();
1846
1847 result
1848 }
1849
1850 /// Set an input handler, such as [`ElementInputHandler`][element_input_handler], which interfaces with the
1851 /// platform to receive textual input with proper integration with concerns such
1852 /// as IME interactions.
1853 ///
1854 /// [element_input_handler]: crate::ElementInputHandler
1855 pub fn handle_input(
1856 &mut self,
1857 focus_handle: &FocusHandle,
1858 input_handler: impl PlatformInputHandler,
1859 ) {
1860 if focus_handle.is_focused(self) {
1861 self.window
1862 .platform_window
1863 .set_input_handler(Box::new(input_handler));
1864 }
1865 }
1866
1867 pub fn on_window_should_close(&mut self, f: impl Fn(&mut WindowContext) -> bool + 'static) {
1868 let mut this = self.to_async();
1869 self.window
1870 .platform_window
1871 .on_should_close(Box::new(move || this.update(|_, cx| f(cx)).unwrap_or(true)))
1872 }
1873}
1874
1875impl Context for WindowContext<'_> {
1876 type Result<T> = T;
1877
1878 fn new_model<T>(&mut self, build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T) -> Model<T>
1879 where
1880 T: 'static,
1881 {
1882 let slot = self.app.entities.reserve();
1883 let model = build_model(&mut ModelContext::new(&mut *self.app, slot.downgrade()));
1884 self.entities.insert(slot, model)
1885 }
1886
1887 fn update_model<T: 'static, R>(
1888 &mut self,
1889 model: &Model<T>,
1890 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
1891 ) -> R {
1892 let mut entity = self.entities.lease(model);
1893 let result = update(
1894 &mut *entity,
1895 &mut ModelContext::new(&mut *self.app, model.downgrade()),
1896 );
1897 self.entities.end_lease(entity);
1898 result
1899 }
1900
1901 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
1902 where
1903 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
1904 {
1905 if window == self.window.handle {
1906 let root_view = self.window.root_view.clone().unwrap();
1907 Ok(update(root_view, self))
1908 } else {
1909 window.update(self.app, update)
1910 }
1911 }
1912
1913 fn read_model<T, R>(
1914 &self,
1915 handle: &Model<T>,
1916 read: impl FnOnce(&T, &AppContext) -> R,
1917 ) -> Self::Result<R>
1918 where
1919 T: 'static,
1920 {
1921 let entity = self.entities.read(handle);
1922 read(entity, &*self.app)
1923 }
1924
1925 fn read_window<T, R>(
1926 &self,
1927 window: &WindowHandle<T>,
1928 read: impl FnOnce(View<T>, &AppContext) -> R,
1929 ) -> Result<R>
1930 where
1931 T: 'static,
1932 {
1933 if window.any_handle == self.window.handle {
1934 let root_view = self
1935 .window
1936 .root_view
1937 .clone()
1938 .unwrap()
1939 .downcast::<T>()
1940 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
1941 Ok(read(root_view, self))
1942 } else {
1943 self.app.read_window(window, read)
1944 }
1945 }
1946}
1947
1948impl VisualContext for WindowContext<'_> {
1949 fn new_view<V>(
1950 &mut self,
1951 build_view_state: impl FnOnce(&mut ViewContext<'_, V>) -> V,
1952 ) -> Self::Result<View<V>>
1953 where
1954 V: 'static + Render,
1955 {
1956 let slot = self.app.entities.reserve();
1957 let view = View {
1958 model: slot.clone(),
1959 };
1960 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
1961 let entity = build_view_state(&mut cx);
1962 cx.entities.insert(slot, entity);
1963
1964 cx.new_view_observers
1965 .clone()
1966 .retain(&TypeId::of::<V>(), |observer| {
1967 let any_view = AnyView::from(view.clone());
1968 (observer)(any_view, self);
1969 true
1970 });
1971
1972 view
1973 }
1974
1975 /// Update the given view. Prefer calling `View::update` instead, which calls this method.
1976 fn update_view<T: 'static, R>(
1977 &mut self,
1978 view: &View<T>,
1979 update: impl FnOnce(&mut T, &mut ViewContext<'_, T>) -> R,
1980 ) -> Self::Result<R> {
1981 let mut lease = self.app.entities.lease(&view.model);
1982 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, view);
1983 let result = update(&mut *lease, &mut cx);
1984 cx.app.entities.end_lease(lease);
1985 result
1986 }
1987
1988 fn replace_root_view<V>(
1989 &mut self,
1990 build_view: impl FnOnce(&mut ViewContext<'_, V>) -> V,
1991 ) -> Self::Result<View<V>>
1992 where
1993 V: 'static + Render,
1994 {
1995 let view = self.new_view(build_view);
1996 self.window.root_view = Some(view.clone().into());
1997 self.notify();
1998 view
1999 }
2000
2001 fn focus_view<V: crate::FocusableView>(&mut self, view: &View<V>) -> Self::Result<()> {
2002 self.update_view(view, |view, cx| {
2003 view.focus_handle(cx).clone().focus(cx);
2004 })
2005 }
2006
2007 fn dismiss_view<V>(&mut self, view: &View<V>) -> Self::Result<()>
2008 where
2009 V: ManagedView,
2010 {
2011 self.update_view(view, |_, cx| cx.emit(DismissEvent))
2012 }
2013}
2014
2015impl<'a> std::ops::Deref for WindowContext<'a> {
2016 type Target = AppContext;
2017
2018 fn deref(&self) -> &Self::Target {
2019 self.app
2020 }
2021}
2022
2023impl<'a> std::ops::DerefMut for WindowContext<'a> {
2024 fn deref_mut(&mut self) -> &mut Self::Target {
2025 self.app
2026 }
2027}
2028
2029impl<'a> Borrow<AppContext> for WindowContext<'a> {
2030 fn borrow(&self) -> &AppContext {
2031 self.app
2032 }
2033}
2034
2035impl<'a> BorrowMut<AppContext> for WindowContext<'a> {
2036 fn borrow_mut(&mut self) -> &mut AppContext {
2037 self.app
2038 }
2039}
2040
2041pub trait BorrowWindow: BorrowMut<Window> + BorrowMut<AppContext> {
2042 fn app_mut(&mut self) -> &mut AppContext {
2043 self.borrow_mut()
2044 }
2045
2046 fn app(&self) -> &AppContext {
2047 self.borrow()
2048 }
2049
2050 fn window(&self) -> &Window {
2051 self.borrow()
2052 }
2053
2054 fn window_mut(&mut self) -> &mut Window {
2055 self.borrow_mut()
2056 }
2057
2058 /// Pushes the given element id onto the global stack and invokes the given closure
2059 /// with a `GlobalElementId`, which disambiguates the given id in the context of its ancestor
2060 /// ids. Because elements are discarded and recreated on each frame, the `GlobalElementId` is
2061 /// used to associate state with identified elements across separate frames.
2062 fn with_element_id<R>(
2063 &mut self,
2064 id: Option<impl Into<ElementId>>,
2065 f: impl FnOnce(&mut Self) -> R,
2066 ) -> R {
2067 if let Some(id) = id.map(Into::into) {
2068 let window = self.window_mut();
2069 window.element_id_stack.push(id);
2070 let result = f(self);
2071 let window: &mut Window = self.borrow_mut();
2072 window.element_id_stack.pop();
2073 result
2074 } else {
2075 f(self)
2076 }
2077 }
2078
2079 /// Invoke the given function with the given content mask after intersecting it
2080 /// with the current mask.
2081 fn with_content_mask<R>(
2082 &mut self,
2083 mask: Option<ContentMask<Pixels>>,
2084 f: impl FnOnce(&mut Self) -> R,
2085 ) -> R {
2086 if let Some(mask) = mask {
2087 let mask = mask.intersect(&self.content_mask());
2088 self.window_mut().next_frame.content_mask_stack.push(mask);
2089 let result = f(self);
2090 self.window_mut().next_frame.content_mask_stack.pop();
2091 result
2092 } else {
2093 f(self)
2094 }
2095 }
2096
2097 /// Invoke the given function with the content mask reset to that
2098 /// of the window.
2099 fn break_content_mask<R>(&mut self, f: impl FnOnce(&mut Self) -> R) -> R {
2100 let mask = ContentMask {
2101 bounds: Bounds {
2102 origin: Point::default(),
2103 size: self.window().viewport_size,
2104 },
2105 };
2106 let new_stacking_order_id =
2107 post_inc(&mut self.window_mut().next_frame.next_stacking_order_id);
2108 let old_stacking_order = mem::take(&mut self.window_mut().next_frame.z_index_stack);
2109 self.window_mut().next_frame.z_index_stack.id = new_stacking_order_id;
2110 self.window_mut().next_frame.content_mask_stack.push(mask);
2111 let result = f(self);
2112 self.window_mut().next_frame.content_mask_stack.pop();
2113 self.window_mut().next_frame.z_index_stack = old_stacking_order;
2114 result
2115 }
2116
2117 /// Called during painting to invoke the given closure in a new stacking context. The given
2118 /// z-index is interpreted relative to the previous call to `stack`.
2119 fn with_z_index<R>(&mut self, z_index: u8, f: impl FnOnce(&mut Self) -> R) -> R {
2120 let new_stacking_order_id =
2121 post_inc(&mut self.window_mut().next_frame.next_stacking_order_id);
2122 let old_stacking_order_id = mem::replace(
2123 &mut self.window_mut().next_frame.z_index_stack.id,
2124 new_stacking_order_id,
2125 );
2126 self.window_mut().next_frame.z_index_stack.id = new_stacking_order_id;
2127 self.window_mut().next_frame.z_index_stack.push(z_index);
2128 let result = f(self);
2129 self.window_mut().next_frame.z_index_stack.id = old_stacking_order_id;
2130 self.window_mut().next_frame.z_index_stack.pop();
2131 result
2132 }
2133
2134 fn with_view_id<R>(&mut self, view_id: EntityId, f: impl FnOnce(&mut Self) -> R) -> R {
2135 self.window_mut().next_frame.view_stack.push(view_id);
2136 let result = f(self);
2137 self.window_mut().next_frame.view_stack.pop();
2138 result
2139 }
2140
2141 /// Update the global element offset relative to the current offset. This is used to implement
2142 /// scrolling.
2143 fn with_element_offset<R>(
2144 &mut self,
2145 offset: Point<Pixels>,
2146 f: impl FnOnce(&mut Self) -> R,
2147 ) -> R {
2148 if offset.is_zero() {
2149 return f(self);
2150 };
2151
2152 let abs_offset = self.element_offset() + offset;
2153 self.with_absolute_element_offset(abs_offset, f)
2154 }
2155
2156 /// Update the global element offset based on the given offset. This is used to implement
2157 /// drag handles and other manual painting of elements.
2158 fn with_absolute_element_offset<R>(
2159 &mut self,
2160 offset: Point<Pixels>,
2161 f: impl FnOnce(&mut Self) -> R,
2162 ) -> R {
2163 self.window_mut()
2164 .next_frame
2165 .element_offset_stack
2166 .push(offset);
2167 let result = f(self);
2168 self.window_mut().next_frame.element_offset_stack.pop();
2169 result
2170 }
2171
2172 /// Obtain the current element offset.
2173 fn element_offset(&self) -> Point<Pixels> {
2174 self.window()
2175 .next_frame
2176 .element_offset_stack
2177 .last()
2178 .copied()
2179 .unwrap_or_default()
2180 }
2181
2182 /// Update or initialize state for an element with the given id that lives across multiple
2183 /// frames. If an element with this id existed in the rendered frame, its state will be passed
2184 /// to the given closure. The state returned by the closure will be stored so it can be referenced
2185 /// when drawing the next frame.
2186 fn with_element_state<S, R>(
2187 &mut self,
2188 id: ElementId,
2189 f: impl FnOnce(Option<S>, &mut Self) -> (R, S),
2190 ) -> R
2191 where
2192 S: 'static,
2193 {
2194 self.with_element_id(Some(id), |cx| {
2195 let global_id = cx.window().element_id_stack.clone();
2196
2197 if let Some(any) = cx
2198 .window_mut()
2199 .next_frame
2200 .element_states
2201 .remove(&global_id)
2202 .or_else(|| {
2203 cx.window_mut()
2204 .rendered_frame
2205 .element_states
2206 .remove(&global_id)
2207 })
2208 {
2209 let ElementStateBox {
2210 inner,
2211
2212 #[cfg(debug_assertions)]
2213 type_name
2214 } = any;
2215 // Using the extra inner option to avoid needing to reallocate a new box.
2216 let mut state_box = inner
2217 .downcast::<Option<S>>()
2218 .map_err(|_| {
2219 #[cfg(debug_assertions)]
2220 {
2221 anyhow!(
2222 "invalid element state type for id, requested_type {:?}, actual type: {:?}",
2223 std::any::type_name::<S>(),
2224 type_name
2225 )
2226 }
2227
2228 #[cfg(not(debug_assertions))]
2229 {
2230 anyhow!(
2231 "invalid element state type for id, requested_type {:?}",
2232 std::any::type_name::<S>(),
2233 )
2234 }
2235 })
2236 .unwrap();
2237
2238 // Actual: Option<AnyElement> <- View
2239 // Requested: () <- AnyElemet
2240 let state = state_box
2241 .take()
2242 .expect("element state is already on the stack");
2243 let (result, state) = f(Some(state), cx);
2244 state_box.replace(state);
2245 cx.window_mut()
2246 .next_frame
2247 .element_states
2248 .insert(global_id, ElementStateBox {
2249 inner: state_box,
2250
2251 #[cfg(debug_assertions)]
2252 type_name
2253 });
2254 result
2255 } else {
2256 let (result, state) = f(None, cx);
2257 cx.window_mut()
2258 .next_frame
2259 .element_states
2260 .insert(global_id,
2261 ElementStateBox {
2262 inner: Box::new(Some(state)),
2263
2264 #[cfg(debug_assertions)]
2265 type_name: std::any::type_name::<S>()
2266 }
2267
2268 );
2269 result
2270 }
2271 })
2272 }
2273
2274 /// Obtain the current content mask.
2275 fn content_mask(&self) -> ContentMask<Pixels> {
2276 self.window()
2277 .next_frame
2278 .content_mask_stack
2279 .last()
2280 .cloned()
2281 .unwrap_or_else(|| ContentMask {
2282 bounds: Bounds {
2283 origin: Point::default(),
2284 size: self.window().viewport_size,
2285 },
2286 })
2287 }
2288
2289 /// The size of an em for the base font of the application. Adjusting this value allows the
2290 /// UI to scale, just like zooming a web page.
2291 fn rem_size(&self) -> Pixels {
2292 self.window().rem_size
2293 }
2294}
2295
2296impl Borrow<Window> for WindowContext<'_> {
2297 fn borrow(&self) -> &Window {
2298 self.window
2299 }
2300}
2301
2302impl BorrowMut<Window> for WindowContext<'_> {
2303 fn borrow_mut(&mut self) -> &mut Window {
2304 self.window
2305 }
2306}
2307
2308impl<T> BorrowWindow for T where T: BorrowMut<AppContext> + BorrowMut<Window> {}
2309
2310pub struct ViewContext<'a, V> {
2311 window_cx: WindowContext<'a>,
2312 view: &'a View<V>,
2313}
2314
2315impl<V> Borrow<AppContext> for ViewContext<'_, V> {
2316 fn borrow(&self) -> &AppContext {
2317 &*self.window_cx.app
2318 }
2319}
2320
2321impl<V> BorrowMut<AppContext> for ViewContext<'_, V> {
2322 fn borrow_mut(&mut self) -> &mut AppContext {
2323 &mut *self.window_cx.app
2324 }
2325}
2326
2327impl<V> Borrow<Window> for ViewContext<'_, V> {
2328 fn borrow(&self) -> &Window {
2329 &*self.window_cx.window
2330 }
2331}
2332
2333impl<V> BorrowMut<Window> for ViewContext<'_, V> {
2334 fn borrow_mut(&mut self) -> &mut Window {
2335 &mut *self.window_cx.window
2336 }
2337}
2338
2339impl<'a, V: 'static> ViewContext<'a, V> {
2340 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window, view: &'a View<V>) -> Self {
2341 Self {
2342 window_cx: WindowContext::new(app, window),
2343 view,
2344 }
2345 }
2346
2347 pub fn entity_id(&self) -> EntityId {
2348 self.view.entity_id()
2349 }
2350
2351 pub fn view(&self) -> &View<V> {
2352 self.view
2353 }
2354
2355 pub fn model(&self) -> &Model<V> {
2356 &self.view.model
2357 }
2358
2359 /// Access the underlying window context.
2360 pub fn window_context(&mut self) -> &mut WindowContext<'a> {
2361 &mut self.window_cx
2362 }
2363
2364 pub fn on_next_frame(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static)
2365 where
2366 V: 'static,
2367 {
2368 let view = self.view().clone();
2369 self.window_cx.on_next_frame(move |cx| view.update(cx, f));
2370 }
2371
2372 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
2373 /// that are currently on the stack to be returned to the app.
2374 pub fn defer(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static) {
2375 let view = self.view().downgrade();
2376 self.window_cx.defer(move |cx| {
2377 view.update(cx, f).ok();
2378 });
2379 }
2380
2381 pub fn observe<V2, E>(
2382 &mut self,
2383 entity: &E,
2384 mut on_notify: impl FnMut(&mut V, E, &mut ViewContext<'_, V>) + 'static,
2385 ) -> Subscription
2386 where
2387 V2: 'static,
2388 V: 'static,
2389 E: Entity<V2>,
2390 {
2391 let view = self.view().downgrade();
2392 let entity_id = entity.entity_id();
2393 let entity = entity.downgrade();
2394 let window_handle = self.window.handle;
2395 let (subscription, activate) = self.app.observers.insert(
2396 entity_id,
2397 Box::new(move |cx| {
2398 window_handle
2399 .update(cx, |_, cx| {
2400 if let Some(handle) = E::upgrade_from(&entity) {
2401 view.update(cx, |this, cx| on_notify(this, handle, cx))
2402 .is_ok()
2403 } else {
2404 false
2405 }
2406 })
2407 .unwrap_or(false)
2408 }),
2409 );
2410 self.app.defer(move |_| activate());
2411 subscription
2412 }
2413
2414 pub fn subscribe<V2, E, Evt>(
2415 &mut self,
2416 entity: &E,
2417 mut on_event: impl FnMut(&mut V, E, &Evt, &mut ViewContext<'_, V>) + 'static,
2418 ) -> Subscription
2419 where
2420 V2: EventEmitter<Evt>,
2421 E: Entity<V2>,
2422 Evt: 'static,
2423 {
2424 let view = self.view().downgrade();
2425 let entity_id = entity.entity_id();
2426 let handle = entity.downgrade();
2427 let window_handle = self.window.handle;
2428 let (subscription, activate) = self.app.event_listeners.insert(
2429 entity_id,
2430 (
2431 TypeId::of::<Evt>(),
2432 Box::new(move |event, cx| {
2433 window_handle
2434 .update(cx, |_, cx| {
2435 if let Some(handle) = E::upgrade_from(&handle) {
2436 let event = event.downcast_ref().expect("invalid event type");
2437 view.update(cx, |this, cx| on_event(this, handle, event, cx))
2438 .is_ok()
2439 } else {
2440 false
2441 }
2442 })
2443 .unwrap_or(false)
2444 }),
2445 ),
2446 );
2447 self.app.defer(move |_| activate());
2448 subscription
2449 }
2450
2451 /// Register a callback to be invoked when the view is released.
2452 ///
2453 /// The callback receives a handle to the view's window. This handle may be
2454 /// invalid, if the window was closed before the view was released.
2455 pub fn on_release(
2456 &mut self,
2457 on_release: impl FnOnce(&mut V, AnyWindowHandle, &mut AppContext) + 'static,
2458 ) -> Subscription {
2459 let window_handle = self.window.handle;
2460 let (subscription, activate) = self.app.release_listeners.insert(
2461 self.view.model.entity_id,
2462 Box::new(move |this, cx| {
2463 let this = this.downcast_mut().expect("invalid entity type");
2464 on_release(this, window_handle, cx)
2465 }),
2466 );
2467 activate();
2468 subscription
2469 }
2470
2471 pub fn observe_release<V2, E>(
2472 &mut self,
2473 entity: &E,
2474 mut on_release: impl FnMut(&mut V, &mut V2, &mut ViewContext<'_, V>) + 'static,
2475 ) -> Subscription
2476 where
2477 V: 'static,
2478 V2: 'static,
2479 E: Entity<V2>,
2480 {
2481 let view = self.view().downgrade();
2482 let entity_id = entity.entity_id();
2483 let window_handle = self.window.handle;
2484 let (subscription, activate) = self.app.release_listeners.insert(
2485 entity_id,
2486 Box::new(move |entity, cx| {
2487 let entity = entity.downcast_mut().expect("invalid entity type");
2488 let _ = window_handle.update(cx, |_, cx| {
2489 view.update(cx, |this, cx| on_release(this, entity, cx))
2490 });
2491 }),
2492 );
2493 activate();
2494 subscription
2495 }
2496
2497 pub fn notify(&mut self) {
2498 let mut dirty_view_id = Some(self.view.entity_id());
2499 while let Some(view_id) = dirty_view_id {
2500 if self.window_cx.window.dirty_views.insert(view_id) {
2501 dirty_view_id = self
2502 .window_cx
2503 .window
2504 .rendered_frame
2505 .view_parents
2506 .get(&view_id)
2507 .copied();
2508 } else {
2509 break;
2510 }
2511 }
2512
2513 if !self.window.drawing {
2514 self.window_cx.notify();
2515 self.window_cx.app.push_effect(Effect::Notify {
2516 emitter: self.view.model.entity_id,
2517 });
2518 }
2519 }
2520
2521 pub fn observe_window_bounds(
2522 &mut self,
2523 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2524 ) -> Subscription {
2525 let view = self.view.downgrade();
2526 let (subscription, activate) = self.window.bounds_observers.insert(
2527 (),
2528 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
2529 );
2530 activate();
2531 subscription
2532 }
2533
2534 pub fn observe_window_activation(
2535 &mut self,
2536 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2537 ) -> Subscription {
2538 let view = self.view.downgrade();
2539 let (subscription, activate) = self.window.activation_observers.insert(
2540 (),
2541 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
2542 );
2543 activate();
2544 subscription
2545 }
2546
2547 /// Register a listener to be called when the given focus handle receives focus.
2548 /// Returns a subscription and persists until the subscription is dropped.
2549 pub fn on_focus(
2550 &mut self,
2551 handle: &FocusHandle,
2552 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2553 ) -> Subscription {
2554 let view = self.view.downgrade();
2555 let focus_id = handle.id;
2556 let (subscription, activate) = self.window.focus_listeners.insert(
2557 (),
2558 Box::new(move |event, cx| {
2559 view.update(cx, |view, cx| {
2560 if event.previous_focus_path.last() != Some(&focus_id)
2561 && event.current_focus_path.last() == Some(&focus_id)
2562 {
2563 listener(view, cx)
2564 }
2565 })
2566 .is_ok()
2567 }),
2568 );
2569 self.app.defer(move |_| activate());
2570 subscription
2571 }
2572
2573 /// Register a listener to be called when the given focus handle or one of its descendants receives focus.
2574 /// Returns a subscription and persists until the subscription is dropped.
2575 pub fn on_focus_in(
2576 &mut self,
2577 handle: &FocusHandle,
2578 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2579 ) -> Subscription {
2580 let view = self.view.downgrade();
2581 let focus_id = handle.id;
2582 let (subscription, activate) = self.window.focus_listeners.insert(
2583 (),
2584 Box::new(move |event, cx| {
2585 view.update(cx, |view, cx| {
2586 if !event.previous_focus_path.contains(&focus_id)
2587 && event.current_focus_path.contains(&focus_id)
2588 {
2589 listener(view, cx)
2590 }
2591 })
2592 .is_ok()
2593 }),
2594 );
2595 self.app.defer(move |_| activate());
2596 subscription
2597 }
2598
2599 /// Register a listener to be called when the given focus handle loses focus.
2600 /// Returns a subscription and persists until the subscription is dropped.
2601 pub fn on_blur(
2602 &mut self,
2603 handle: &FocusHandle,
2604 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2605 ) -> Subscription {
2606 let view = self.view.downgrade();
2607 let focus_id = handle.id;
2608 let (subscription, activate) = self.window.focus_listeners.insert(
2609 (),
2610 Box::new(move |event, cx| {
2611 view.update(cx, |view, cx| {
2612 if event.previous_focus_path.last() == Some(&focus_id)
2613 && event.current_focus_path.last() != Some(&focus_id)
2614 {
2615 listener(view, cx)
2616 }
2617 })
2618 .is_ok()
2619 }),
2620 );
2621 self.app.defer(move |_| activate());
2622 subscription
2623 }
2624
2625 /// Register a listener to be called when the window loses focus.
2626 /// Returns a subscription and persists until the subscription is dropped.
2627 pub fn on_blur_window(
2628 &mut self,
2629 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2630 ) -> Subscription {
2631 let view = self.view.downgrade();
2632 let (subscription, activate) = self.window.blur_listeners.insert(
2633 (),
2634 Box::new(move |cx| view.update(cx, |view, cx| listener(view, cx)).is_ok()),
2635 );
2636 activate();
2637 subscription
2638 }
2639
2640 /// Register a listener to be called when the given focus handle or one of its descendants loses focus.
2641 /// Returns a subscription and persists until the subscription is dropped.
2642 pub fn on_focus_out(
2643 &mut self,
2644 handle: &FocusHandle,
2645 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2646 ) -> Subscription {
2647 let view = self.view.downgrade();
2648 let focus_id = handle.id;
2649 let (subscription, activate) = self.window.focus_listeners.insert(
2650 (),
2651 Box::new(move |event, cx| {
2652 view.update(cx, |view, cx| {
2653 if event.previous_focus_path.contains(&focus_id)
2654 && !event.current_focus_path.contains(&focus_id)
2655 {
2656 listener(view, cx)
2657 }
2658 })
2659 .is_ok()
2660 }),
2661 );
2662 self.app.defer(move |_| activate());
2663 subscription
2664 }
2665
2666 pub fn spawn<Fut, R>(
2667 &mut self,
2668 f: impl FnOnce(WeakView<V>, AsyncWindowContext) -> Fut,
2669 ) -> Task<R>
2670 where
2671 R: 'static,
2672 Fut: Future<Output = R> + 'static,
2673 {
2674 let view = self.view().downgrade();
2675 self.window_cx.spawn(|cx| f(view, cx))
2676 }
2677
2678 pub fn update_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
2679 where
2680 G: 'static,
2681 {
2682 let mut global = self.app.lease_global::<G>();
2683 let result = f(&mut global, self);
2684 self.app.end_global_lease(global);
2685 result
2686 }
2687
2688 pub fn observe_global<G: 'static>(
2689 &mut self,
2690 mut f: impl FnMut(&mut V, &mut ViewContext<'_, V>) + 'static,
2691 ) -> Subscription {
2692 let window_handle = self.window.handle;
2693 let view = self.view().downgrade();
2694 let (subscription, activate) = self.global_observers.insert(
2695 TypeId::of::<G>(),
2696 Box::new(move |cx| {
2697 window_handle
2698 .update(cx, |_, cx| view.update(cx, |view, cx| f(view, cx)).is_ok())
2699 .unwrap_or(false)
2700 }),
2701 );
2702 self.app.defer(move |_| activate());
2703 subscription
2704 }
2705
2706 pub fn on_mouse_event<Event: 'static>(
2707 &mut self,
2708 handler: impl Fn(&mut V, &Event, DispatchPhase, &mut ViewContext<V>) + 'static,
2709 ) {
2710 let handle = self.view().clone();
2711 self.window_cx.on_mouse_event(move |event, phase, cx| {
2712 handle.update(cx, |view, cx| {
2713 handler(view, event, phase, cx);
2714 })
2715 });
2716 }
2717
2718 pub fn on_key_event<Event: 'static>(
2719 &mut self,
2720 handler: impl Fn(&mut V, &Event, DispatchPhase, &mut ViewContext<V>) + 'static,
2721 ) {
2722 let handle = self.view().clone();
2723 self.window_cx.on_key_event(move |event, phase, cx| {
2724 handle.update(cx, |view, cx| {
2725 handler(view, event, phase, cx);
2726 })
2727 });
2728 }
2729
2730 pub fn on_action(
2731 &mut self,
2732 action_type: TypeId,
2733 listener: impl Fn(&mut V, &dyn Any, DispatchPhase, &mut ViewContext<V>) + 'static,
2734 ) {
2735 let handle = self.view().clone();
2736 self.window_cx
2737 .on_action(action_type, move |action, phase, cx| {
2738 handle.update(cx, |view, cx| {
2739 listener(view, action, phase, cx);
2740 })
2741 });
2742 }
2743
2744 pub fn emit<Evt>(&mut self, event: Evt)
2745 where
2746 Evt: 'static,
2747 V: EventEmitter<Evt>,
2748 {
2749 let emitter = self.view.model.entity_id;
2750 self.app.push_effect(Effect::Emit {
2751 emitter,
2752 event_type: TypeId::of::<Evt>(),
2753 event: Box::new(event),
2754 });
2755 }
2756
2757 pub fn focus_self(&mut self)
2758 where
2759 V: FocusableView,
2760 {
2761 self.defer(|view, cx| view.focus_handle(cx).focus(cx))
2762 }
2763
2764 pub fn listener<E>(
2765 &self,
2766 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
2767 ) -> impl Fn(&E, &mut WindowContext) + 'static {
2768 let view = self.view().downgrade();
2769 move |e: &E, cx: &mut WindowContext| {
2770 view.update(cx, |view, cx| f(view, e, cx)).ok();
2771 }
2772 }
2773}
2774
2775impl<V> Context for ViewContext<'_, V> {
2776 type Result<U> = U;
2777
2778 fn new_model<T: 'static>(
2779 &mut self,
2780 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
2781 ) -> Model<T> {
2782 self.window_cx.new_model(build_model)
2783 }
2784
2785 fn update_model<T: 'static, R>(
2786 &mut self,
2787 model: &Model<T>,
2788 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
2789 ) -> R {
2790 self.window_cx.update_model(model, update)
2791 }
2792
2793 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
2794 where
2795 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
2796 {
2797 self.window_cx.update_window(window, update)
2798 }
2799
2800 fn read_model<T, R>(
2801 &self,
2802 handle: &Model<T>,
2803 read: impl FnOnce(&T, &AppContext) -> R,
2804 ) -> Self::Result<R>
2805 where
2806 T: 'static,
2807 {
2808 self.window_cx.read_model(handle, read)
2809 }
2810
2811 fn read_window<T, R>(
2812 &self,
2813 window: &WindowHandle<T>,
2814 read: impl FnOnce(View<T>, &AppContext) -> R,
2815 ) -> Result<R>
2816 where
2817 T: 'static,
2818 {
2819 self.window_cx.read_window(window, read)
2820 }
2821}
2822
2823impl<V: 'static> VisualContext for ViewContext<'_, V> {
2824 fn new_view<W: Render + 'static>(
2825 &mut self,
2826 build_view_state: impl FnOnce(&mut ViewContext<'_, W>) -> W,
2827 ) -> Self::Result<View<W>> {
2828 self.window_cx.new_view(build_view_state)
2829 }
2830
2831 fn update_view<V2: 'static, R>(
2832 &mut self,
2833 view: &View<V2>,
2834 update: impl FnOnce(&mut V2, &mut ViewContext<'_, V2>) -> R,
2835 ) -> Self::Result<R> {
2836 self.window_cx.update_view(view, update)
2837 }
2838
2839 fn replace_root_view<W>(
2840 &mut self,
2841 build_view: impl FnOnce(&mut ViewContext<'_, W>) -> W,
2842 ) -> Self::Result<View<W>>
2843 where
2844 W: 'static + Render,
2845 {
2846 self.window_cx.replace_root_view(build_view)
2847 }
2848
2849 fn focus_view<W: FocusableView>(&mut self, view: &View<W>) -> Self::Result<()> {
2850 self.window_cx.focus_view(view)
2851 }
2852
2853 fn dismiss_view<W: ManagedView>(&mut self, view: &View<W>) -> Self::Result<()> {
2854 self.window_cx.dismiss_view(view)
2855 }
2856}
2857
2858impl<'a, V> std::ops::Deref for ViewContext<'a, V> {
2859 type Target = WindowContext<'a>;
2860
2861 fn deref(&self) -> &Self::Target {
2862 &self.window_cx
2863 }
2864}
2865
2866impl<'a, V> std::ops::DerefMut for ViewContext<'a, V> {
2867 fn deref_mut(&mut self) -> &mut Self::Target {
2868 &mut self.window_cx
2869 }
2870}
2871
2872// #[derive(Clone, Copy, Eq, PartialEq, Hash)]
2873slotmap::new_key_type! { pub struct WindowId; }
2874
2875impl WindowId {
2876 pub fn as_u64(&self) -> u64 {
2877 self.0.as_ffi()
2878 }
2879}
2880
2881#[derive(Deref, DerefMut)]
2882pub struct WindowHandle<V> {
2883 #[deref]
2884 #[deref_mut]
2885 pub(crate) any_handle: AnyWindowHandle,
2886 state_type: PhantomData<V>,
2887}
2888
2889impl<V: 'static + Render> WindowHandle<V> {
2890 pub fn new(id: WindowId) -> Self {
2891 WindowHandle {
2892 any_handle: AnyWindowHandle {
2893 id,
2894 state_type: TypeId::of::<V>(),
2895 },
2896 state_type: PhantomData,
2897 }
2898 }
2899
2900 pub fn root<C>(&self, cx: &mut C) -> Result<View<V>>
2901 where
2902 C: Context,
2903 {
2904 Flatten::flatten(cx.update_window(self.any_handle, |root_view, _| {
2905 root_view
2906 .downcast::<V>()
2907 .map_err(|_| anyhow!("the type of the window's root view has changed"))
2908 }))
2909 }
2910
2911 pub fn update<C, R>(
2912 &self,
2913 cx: &mut C,
2914 update: impl FnOnce(&mut V, &mut ViewContext<'_, V>) -> R,
2915 ) -> Result<R>
2916 where
2917 C: Context,
2918 {
2919 cx.update_window(self.any_handle, |root_view, cx| {
2920 let view = root_view
2921 .downcast::<V>()
2922 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
2923 Ok(cx.update_view(&view, update))
2924 })?
2925 }
2926
2927 pub fn read<'a>(&self, cx: &'a AppContext) -> Result<&'a V> {
2928 let x = cx
2929 .windows
2930 .get(self.id)
2931 .and_then(|window| {
2932 window
2933 .as_ref()
2934 .and_then(|window| window.root_view.clone())
2935 .map(|root_view| root_view.downcast::<V>())
2936 })
2937 .ok_or_else(|| anyhow!("window not found"))?
2938 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
2939
2940 Ok(x.read(cx))
2941 }
2942
2943 pub fn read_with<C, R>(&self, cx: &C, read_with: impl FnOnce(&V, &AppContext) -> R) -> Result<R>
2944 where
2945 C: Context,
2946 {
2947 cx.read_window(self, |root_view, cx| read_with(root_view.read(cx), cx))
2948 }
2949
2950 pub fn root_view<C>(&self, cx: &C) -> Result<View<V>>
2951 where
2952 C: Context,
2953 {
2954 cx.read_window(self, |root_view, _cx| root_view.clone())
2955 }
2956
2957 pub fn is_active(&self, cx: &AppContext) -> Option<bool> {
2958 cx.windows
2959 .get(self.id)
2960 .and_then(|window| window.as_ref().map(|window| window.active))
2961 }
2962}
2963
2964impl<V> Copy for WindowHandle<V> {}
2965
2966impl<V> Clone for WindowHandle<V> {
2967 fn clone(&self) -> Self {
2968 *self
2969 }
2970}
2971
2972impl<V> PartialEq for WindowHandle<V> {
2973 fn eq(&self, other: &Self) -> bool {
2974 self.any_handle == other.any_handle
2975 }
2976}
2977
2978impl<V> Eq for WindowHandle<V> {}
2979
2980impl<V> Hash for WindowHandle<V> {
2981 fn hash<H: Hasher>(&self, state: &mut H) {
2982 self.any_handle.hash(state);
2983 }
2984}
2985
2986impl<V: 'static> From<WindowHandle<V>> for AnyWindowHandle {
2987 fn from(val: WindowHandle<V>) -> Self {
2988 val.any_handle
2989 }
2990}
2991
2992#[derive(Copy, Clone, PartialEq, Eq, Hash)]
2993pub struct AnyWindowHandle {
2994 pub(crate) id: WindowId,
2995 state_type: TypeId,
2996}
2997
2998impl AnyWindowHandle {
2999 pub fn window_id(&self) -> WindowId {
3000 self.id
3001 }
3002
3003 pub fn downcast<T: 'static>(&self) -> Option<WindowHandle<T>> {
3004 if TypeId::of::<T>() == self.state_type {
3005 Some(WindowHandle {
3006 any_handle: *self,
3007 state_type: PhantomData,
3008 })
3009 } else {
3010 None
3011 }
3012 }
3013
3014 pub fn update<C, R>(
3015 self,
3016 cx: &mut C,
3017 update: impl FnOnce(AnyView, &mut WindowContext<'_>) -> R,
3018 ) -> Result<R>
3019 where
3020 C: Context,
3021 {
3022 cx.update_window(self, update)
3023 }
3024
3025 pub fn read<T, C, R>(self, cx: &C, read: impl FnOnce(View<T>, &AppContext) -> R) -> Result<R>
3026 where
3027 C: Context,
3028 T: 'static,
3029 {
3030 let view = self
3031 .downcast::<T>()
3032 .context("the type of the window's root view has changed")?;
3033
3034 cx.read_window(&view, read)
3035 }
3036}
3037
3038// #[cfg(any(test, feature = "test-support"))]
3039// impl From<SmallVec<[u32; 16]>> for StackingOrder {
3040// fn from(small_vec: SmallVec<[u32; 16]>) -> Self {
3041// StackingOrder(small_vec)
3042// }
3043// }
3044
3045#[derive(Clone, Debug, Eq, PartialEq, Hash)]
3046pub enum ElementId {
3047 View(EntityId),
3048 Integer(usize),
3049 Name(SharedString),
3050 FocusHandle(FocusId),
3051 NamedInteger(SharedString, usize),
3052}
3053
3054impl ElementId {
3055 pub(crate) fn from_entity_id(entity_id: EntityId) -> Self {
3056 ElementId::View(entity_id)
3057 }
3058}
3059
3060impl TryInto<SharedString> for ElementId {
3061 type Error = anyhow::Error;
3062
3063 fn try_into(self) -> anyhow::Result<SharedString> {
3064 if let ElementId::Name(name) = self {
3065 Ok(name)
3066 } else {
3067 Err(anyhow!("element id is not string"))
3068 }
3069 }
3070}
3071
3072impl From<usize> for ElementId {
3073 fn from(id: usize) -> Self {
3074 ElementId::Integer(id)
3075 }
3076}
3077
3078impl From<i32> for ElementId {
3079 fn from(id: i32) -> Self {
3080 Self::Integer(id as usize)
3081 }
3082}
3083
3084impl From<SharedString> for ElementId {
3085 fn from(name: SharedString) -> Self {
3086 ElementId::Name(name)
3087 }
3088}
3089
3090impl From<&'static str> for ElementId {
3091 fn from(name: &'static str) -> Self {
3092 ElementId::Name(name.into())
3093 }
3094}
3095
3096impl<'a> From<&'a FocusHandle> for ElementId {
3097 fn from(handle: &'a FocusHandle) -> Self {
3098 ElementId::FocusHandle(handle.id)
3099 }
3100}
3101
3102impl From<(&'static str, EntityId)> for ElementId {
3103 fn from((name, id): (&'static str, EntityId)) -> Self {
3104 ElementId::NamedInteger(name.into(), id.as_u64() as usize)
3105 }
3106}
3107
3108impl From<(&'static str, usize)> for ElementId {
3109 fn from((name, id): (&'static str, usize)) -> Self {
3110 ElementId::NamedInteger(name.into(), id)
3111 }
3112}
3113
3114impl From<(&'static str, u64)> for ElementId {
3115 fn from((name, id): (&'static str, u64)) -> Self {
3116 ElementId::NamedInteger(name.into(), id as usize)
3117 }
3118}
3119
3120/// A rectangle, to be rendered on the screen by GPUI at the given position and size.
3121#[derive(Clone)]
3122pub struct PaintQuad {
3123 bounds: Bounds<Pixels>,
3124 corner_radii: Corners<Pixels>,
3125 background: Hsla,
3126 border_widths: Edges<Pixels>,
3127 border_color: Hsla,
3128}
3129
3130impl PaintQuad {
3131 /// Set the corner radii of the quad.
3132 pub fn corner_radii(self, corner_radii: impl Into<Corners<Pixels>>) -> Self {
3133 PaintQuad {
3134 corner_radii: corner_radii.into(),
3135 ..self
3136 }
3137 }
3138
3139 /// Set the border widths of the quad.
3140 pub fn border_widths(self, border_widths: impl Into<Edges<Pixels>>) -> Self {
3141 PaintQuad {
3142 border_widths: border_widths.into(),
3143 ..self
3144 }
3145 }
3146
3147 /// Set the border color of the quad.
3148 pub fn border_color(self, border_color: impl Into<Hsla>) -> Self {
3149 PaintQuad {
3150 border_color: border_color.into(),
3151 ..self
3152 }
3153 }
3154
3155 /// Set the background color of the quad.
3156 pub fn background(self, background: impl Into<Hsla>) -> Self {
3157 PaintQuad {
3158 background: background.into(),
3159 ..self
3160 }
3161 }
3162}
3163
3164/// Create a quad with the given parameters.
3165pub fn quad(
3166 bounds: Bounds<Pixels>,
3167 corner_radii: impl Into<Corners<Pixels>>,
3168 background: impl Into<Hsla>,
3169 border_widths: impl Into<Edges<Pixels>>,
3170 border_color: impl Into<Hsla>,
3171) -> PaintQuad {
3172 PaintQuad {
3173 bounds,
3174 corner_radii: corner_radii.into(),
3175 background: background.into(),
3176 border_widths: border_widths.into(),
3177 border_color: border_color.into(),
3178 }
3179}
3180
3181/// Create a filled quad with the given bounds and background color.
3182pub fn fill(bounds: impl Into<Bounds<Pixels>>, background: impl Into<Hsla>) -> PaintQuad {
3183 PaintQuad {
3184 bounds: bounds.into(),
3185 corner_radii: (0.).into(),
3186 background: background.into(),
3187 border_widths: (0.).into(),
3188 border_color: transparent_black(),
3189 }
3190}
3191
3192/// Create a rectangle outline with the given bounds, border color, and a 1px border width
3193pub fn outline(bounds: impl Into<Bounds<Pixels>>, border_color: impl Into<Hsla>) -> PaintQuad {
3194 PaintQuad {
3195 bounds: bounds.into(),
3196 corner_radii: (0.).into(),
3197 background: transparent_black(),
3198 border_widths: (1.).into(),
3199 border_color: border_color.into(),
3200 }
3201}