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, Shadow, SharedString, Size, Style, SubscriberSet,
11 Subscription, Surface, TaffyLayoutEngine, Task, Underline, UnderlineStyle, View, VisualContext,
12 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) refreshing: bool,
273 pub(crate) drawing: bool,
274 activation_observers: SubscriberSet<(), AnyObserver>,
275 pub(crate) focus: Option<FocusId>,
276 focus_enabled: bool,
277
278 #[cfg(any(test, feature = "test-support"))]
279 pub(crate) focus_invalidated: bool,
280}
281
282pub(crate) struct ElementStateBox {
283 inner: Box<dyn Any>,
284 parent_view_id: EntityId,
285 #[cfg(debug_assertions)]
286 type_name: &'static str,
287}
288
289pub(crate) struct Frame {
290 focus: Option<FocusId>,
291 pub(crate) element_states: FxHashMap<GlobalElementId, ElementStateBox>,
292 mouse_listeners: FxHashMap<TypeId, Vec<(StackingOrder, EntityId, AnyMouseListener)>>,
293 pub(crate) dispatch_tree: DispatchTree,
294 pub(crate) scene: Scene,
295 pub(crate) depth_map: Vec<(StackingOrder, EntityId, Bounds<Pixels>)>,
296 pub(crate) z_index_stack: StackingOrder,
297 pub(crate) next_stacking_order_id: u32,
298 content_mask_stack: Vec<ContentMask<Pixels>>,
299 element_offset_stack: Vec<Point<Pixels>>,
300 pub(crate) view_stack: Vec<EntityId>,
301 pub(crate) reused_views: FxHashSet<EntityId>,
302}
303
304impl Frame {
305 fn new(dispatch_tree: DispatchTree) -> Self {
306 Frame {
307 focus: None,
308 element_states: FxHashMap::default(),
309 mouse_listeners: FxHashMap::default(),
310 dispatch_tree,
311 scene: Scene::default(),
312 z_index_stack: StackingOrder::default(),
313 next_stacking_order_id: 0,
314 depth_map: Default::default(),
315 content_mask_stack: Vec::new(),
316 element_offset_stack: Vec::new(),
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.reused_views.clear();
329 self.scene.clear();
330 debug_assert_eq!(self.view_stack.len(), 0);
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(handle, options);
347 let display_id = platform_window.display().id();
348 let sprite_atlas = platform_window.sprite_atlas();
349 let mouse_position = platform_window.mouse_position();
350 let modifiers = platform_window.modifiers();
351 let content_size = platform_window.content_size();
352 let scale_factor = platform_window.scale_factor();
353 let bounds = platform_window.bounds();
354
355 platform_window.on_request_frame(Box::new({
356 let mut cx = cx.to_async();
357 move || {
358 handle.update(&mut cx, |_, cx| cx.draw()).log_err();
359 }
360 }));
361 platform_window.on_resize(Box::new({
362 let mut cx = cx.to_async();
363 move |_, _| {
364 handle
365 .update(&mut cx, |_, cx| cx.window_bounds_changed())
366 .log_err();
367 }
368 }));
369 platform_window.on_moved(Box::new({
370 let mut cx = cx.to_async();
371 move || {
372 handle
373 .update(&mut cx, |_, cx| cx.window_bounds_changed())
374 .log_err();
375 }
376 }));
377 platform_window.on_active_status_change(Box::new({
378 let mut cx = cx.to_async();
379 move |active| {
380 handle
381 .update(&mut cx, |_, cx| {
382 cx.window.active = active;
383 cx.window
384 .activation_observers
385 .clone()
386 .retain(&(), |callback| callback(cx));
387 })
388 .log_err();
389 }
390 }));
391
392 platform_window.on_input({
393 let mut cx = cx.to_async();
394 Box::new(move |event| {
395 handle
396 .update(&mut cx, |_, cx| cx.dispatch_event(event))
397 .log_err()
398 .unwrap_or(false)
399 })
400 });
401
402 Window {
403 handle,
404 removed: false,
405 platform_window,
406 display_id,
407 sprite_atlas,
408 rem_size: px(16.),
409 viewport_size: content_size,
410 layout_engine: Some(TaffyLayoutEngine::new()),
411 root_view: None,
412 element_id_stack: GlobalElementId::default(),
413 rendered_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
414 next_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
415 dirty_views: FxHashSet::default(),
416 focus_handles: Arc::new(RwLock::new(SlotMap::with_key())),
417 focus_listeners: SubscriberSet::new(),
418 blur_listeners: SubscriberSet::new(),
419 default_prevented: true,
420 mouse_position,
421 modifiers,
422 requested_cursor_style: None,
423 scale_factor,
424 bounds,
425 bounds_observers: SubscriberSet::new(),
426 active: false,
427 dirty: false,
428 refreshing: 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 refresh(&mut self) {
484 if !self.window.drawing {
485 self.window.refreshing = true;
486 self.window.dirty = true;
487 }
488 }
489
490 /// Close this window.
491 pub fn remove_window(&mut self) {
492 self.window.removed = true;
493 }
494
495 /// Obtain a new `FocusHandle`, which allows you to track and manipulate the keyboard focus
496 /// for elements rendered within this window.
497 pub fn focus_handle(&mut self) -> FocusHandle {
498 FocusHandle::new(&self.window.focus_handles)
499 }
500
501 /// Obtain the currently focused `FocusHandle`. If no elements are focused, returns `None`.
502 pub fn focused(&self) -> Option<FocusHandle> {
503 self.window
504 .focus
505 .and_then(|id| FocusHandle::for_id(id, &self.window.focus_handles))
506 }
507
508 /// Move focus to the element associated with the given `FocusHandle`.
509 pub fn focus(&mut self, handle: &FocusHandle) {
510 if !self.window.focus_enabled || self.window.focus == Some(handle.id) {
511 return;
512 }
513
514 self.window.focus = Some(handle.id);
515 self.window
516 .rendered_frame
517 .dispatch_tree
518 .clear_pending_keystrokes();
519
520 #[cfg(any(test, feature = "test-support"))]
521 {
522 self.window.focus_invalidated = true;
523 }
524
525 self.refresh();
526 }
527
528 /// Remove focus from all elements within this context's window.
529 pub fn blur(&mut self) {
530 if !self.window.focus_enabled {
531 return;
532 }
533
534 self.window.focus = None;
535 self.refresh();
536 }
537
538 pub fn disable_focus(&mut self) {
539 self.blur();
540 self.window.focus_enabled = false;
541 }
542
543 pub fn dispatch_action(&mut self, action: Box<dyn Action>) {
544 let focus_handle = self.focused();
545
546 self.defer(move |cx| {
547 let node_id = focus_handle
548 .and_then(|handle| {
549 cx.window
550 .rendered_frame
551 .dispatch_tree
552 .focusable_node_id(handle.id)
553 })
554 .unwrap_or_else(|| cx.window.rendered_frame.dispatch_tree.root_node_id());
555
556 cx.propagate_event = true;
557 cx.dispatch_action_on_node(node_id, action);
558 })
559 }
560
561 pub(crate) fn dispatch_keystroke_observers(
562 &mut self,
563 event: &dyn Any,
564 action: Option<Box<dyn Action>>,
565 ) {
566 let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() else {
567 return;
568 };
569
570 self.keystroke_observers
571 .clone()
572 .retain(&(), move |callback| {
573 (callback)(
574 &KeystrokeEvent {
575 keystroke: key_down_event.keystroke.clone(),
576 action: action.as_ref().map(|action| action.boxed_clone()),
577 },
578 self,
579 );
580 true
581 });
582 }
583
584 pub(crate) fn clear_pending_keystrokes(&mut self) {
585 self.window
586 .rendered_frame
587 .dispatch_tree
588 .clear_pending_keystrokes();
589 self.window
590 .next_frame
591 .dispatch_tree
592 .clear_pending_keystrokes();
593 }
594
595 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
596 /// that are currently on the stack to be returned to the app.
597 pub fn defer(&mut self, f: impl FnOnce(&mut WindowContext) + 'static) {
598 let handle = self.window.handle;
599 self.app.defer(move |cx| {
600 handle.update(cx, |_, cx| f(cx)).ok();
601 });
602 }
603
604 pub fn subscribe<Emitter, E, Evt>(
605 &mut self,
606 entity: &E,
607 mut on_event: impl FnMut(E, &Evt, &mut WindowContext<'_>) + 'static,
608 ) -> Subscription
609 where
610 Emitter: EventEmitter<Evt>,
611 E: Entity<Emitter>,
612 Evt: 'static,
613 {
614 let entity_id = entity.entity_id();
615 let entity = entity.downgrade();
616 let window_handle = self.window.handle;
617 let (subscription, activate) = self.app.event_listeners.insert(
618 entity_id,
619 (
620 TypeId::of::<Evt>(),
621 Box::new(move |event, cx| {
622 window_handle
623 .update(cx, |_, cx| {
624 if let Some(handle) = E::upgrade_from(&entity) {
625 let event = event.downcast_ref().expect("invalid event type");
626 on_event(handle, event, cx);
627 true
628 } else {
629 false
630 }
631 })
632 .unwrap_or(false)
633 }),
634 ),
635 );
636 self.app.defer(move |_| activate());
637 subscription
638 }
639
640 /// Create an `AsyncWindowContext`, which has a static lifetime and can be held across
641 /// await points in async code.
642 pub fn to_async(&self) -> AsyncWindowContext {
643 AsyncWindowContext::new(self.app.to_async(), self.window.handle)
644 }
645
646 /// Schedule the given closure to be run directly after the current frame is rendered.
647 pub fn on_next_frame(&mut self, callback: impl FnOnce(&mut WindowContext) + 'static) {
648 let handle = self.window.handle;
649 let display_id = self.window.display_id;
650
651 let mut frame_consumers = std::mem::take(&mut self.app.frame_consumers);
652 if let Entry::Vacant(e) = frame_consumers.entry(display_id) {
653 let (tx, mut rx) = mpsc::unbounded::<()>();
654 self.platform.set_display_link_output_callback(
655 display_id,
656 Box::new(move |_current_time, _output_time| _ = tx.unbounded_send(())),
657 );
658
659 let consumer_task = self.app.spawn(|cx| async move {
660 while rx.next().await.is_some() {
661 cx.update(|cx| {
662 for callback in cx
663 .next_frame_callbacks
664 .get_mut(&display_id)
665 .unwrap()
666 .drain(..)
667 .collect::<SmallVec<[_; 32]>>()
668 {
669 callback(cx);
670 }
671 })
672 .ok();
673
674 // Flush effects, then stop the display link if no new next_frame_callbacks have been added.
675
676 cx.update(|cx| {
677 if cx.next_frame_callbacks.is_empty() {
678 cx.platform.stop_display_link(display_id);
679 }
680 })
681 .ok();
682 }
683 });
684 e.insert(consumer_task);
685 }
686 debug_assert!(self.app.frame_consumers.is_empty());
687 self.app.frame_consumers = frame_consumers;
688
689 if self.next_frame_callbacks.is_empty() {
690 self.platform.start_display_link(display_id);
691 }
692
693 self.next_frame_callbacks
694 .entry(display_id)
695 .or_default()
696 .push(Box::new(move |cx: &mut AppContext| {
697 cx.update_window(handle, |_root_view, cx| callback(cx)).ok();
698 }));
699 }
700
701 /// Spawn the future returned by the given closure on the application thread pool.
702 /// The closure is provided a handle to the current window and an `AsyncWindowContext` for
703 /// use within your future.
704 pub fn spawn<Fut, R>(&mut self, f: impl FnOnce(AsyncWindowContext) -> Fut) -> Task<R>
705 where
706 R: 'static,
707 Fut: Future<Output = R> + 'static,
708 {
709 self.app
710 .spawn(|app| f(AsyncWindowContext::new(app, self.window.handle)))
711 }
712
713 /// Update the global of the given type. The given closure is given simultaneous mutable
714 /// access both to the global and the context.
715 pub fn update_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
716 where
717 G: 'static,
718 {
719 let mut global = self.app.lease_global::<G>();
720 let result = f(&mut global, self);
721 self.app.end_global_lease(global);
722 result
723 }
724
725 #[must_use]
726 /// Add a node to the layout tree for the current frame. Takes the `Style` of the element for which
727 /// layout is being requested, along with the layout ids of any children. This method is called during
728 /// calls to the `Element::layout` trait method and enables any element to participate in layout.
729 pub fn request_layout(
730 &mut self,
731 style: &Style,
732 children: impl IntoIterator<Item = LayoutId>,
733 ) -> LayoutId {
734 self.app.layout_id_buffer.clear();
735 self.app.layout_id_buffer.extend(children);
736 let rem_size = self.rem_size();
737
738 self.window.layout_engine.as_mut().unwrap().request_layout(
739 style,
740 rem_size,
741 &self.app.layout_id_buffer,
742 )
743 }
744
745 /// Add a node to the layout tree for the current frame. Instead of taking a `Style` and children,
746 /// this variant takes a function that is invoked during layout so you can use arbitrary logic to
747 /// determine the element's size. One place this is used internally is when measuring text.
748 ///
749 /// The given closure is invoked at layout time with the known dimensions and available space and
750 /// returns a `Size`.
751 pub fn request_measured_layout<
752 F: FnMut(Size<Option<Pixels>>, Size<AvailableSpace>, &mut WindowContext) -> Size<Pixels>
753 + 'static,
754 >(
755 &mut self,
756 style: Style,
757 measure: F,
758 ) -> LayoutId {
759 let rem_size = self.rem_size();
760 self.window
761 .layout_engine
762 .as_mut()
763 .unwrap()
764 .request_measured_layout(style, rem_size, measure)
765 }
766
767 pub fn layout_style(&self, layout_id: LayoutId) -> Option<&Style> {
768 self.window
769 .layout_engine
770 .as_ref()
771 .unwrap()
772 .requested_style(layout_id)
773 }
774
775 pub fn compute_layout(&mut self, layout_id: LayoutId, available_space: Size<AvailableSpace>) {
776 let mut layout_engine = self.window.layout_engine.take().unwrap();
777 layout_engine.compute_layout(layout_id, available_space, self);
778 self.window.layout_engine = Some(layout_engine);
779 }
780
781 /// Obtain the bounds computed for the given LayoutId relative to the window. This method should not
782 /// be invoked until the paint phase begins, and will usually be invoked by GPUI itself automatically
783 /// in order to pass your element its `Bounds` automatically.
784 pub fn layout_bounds(&mut self, layout_id: LayoutId) -> Bounds<Pixels> {
785 let mut bounds = self
786 .window
787 .layout_engine
788 .as_mut()
789 .unwrap()
790 .layout_bounds(layout_id)
791 .map(Into::into);
792 bounds.origin += self.element_offset();
793 bounds
794 }
795
796 fn window_bounds_changed(&mut self) {
797 self.window.scale_factor = self.window.platform_window.scale_factor();
798 self.window.viewport_size = self.window.platform_window.content_size();
799 self.window.bounds = self.window.platform_window.bounds();
800 self.window.display_id = self.window.platform_window.display().id();
801 self.refresh();
802
803 self.window
804 .bounds_observers
805 .clone()
806 .retain(&(), |callback| callback(self));
807 }
808
809 pub fn window_bounds(&self) -> WindowBounds {
810 self.window.bounds
811 }
812
813 pub fn viewport_size(&self) -> Size<Pixels> {
814 self.window.viewport_size
815 }
816
817 pub fn is_window_active(&self) -> bool {
818 self.window.active
819 }
820
821 pub fn zoom_window(&self) {
822 self.window.platform_window.zoom();
823 }
824
825 pub fn set_window_title(&mut self, title: &str) {
826 self.window.platform_window.set_title(title);
827 }
828
829 pub fn set_window_edited(&mut self, edited: bool) {
830 self.window.platform_window.set_edited(edited);
831 }
832
833 pub fn display(&self) -> Option<Rc<dyn PlatformDisplay>> {
834 self.platform
835 .displays()
836 .into_iter()
837 .find(|display| display.id() == self.window.display_id)
838 }
839
840 pub fn show_character_palette(&self) {
841 self.window.platform_window.show_character_palette();
842 }
843
844 /// The scale factor of the display associated with the window. For example, it could
845 /// return 2.0 for a "retina" display, indicating that each logical pixel should actually
846 /// be rendered as two pixels on screen.
847 pub fn scale_factor(&self) -> f32 {
848 self.window.scale_factor
849 }
850
851 /// The size of an em for the base font of the application. Adjusting this value allows the
852 /// UI to scale, just like zooming a web page.
853 pub fn rem_size(&self) -> Pixels {
854 self.window.rem_size
855 }
856
857 /// Sets the size of an em for the base font of the application. Adjusting this value allows the
858 /// UI to scale, just like zooming a web page.
859 pub fn set_rem_size(&mut self, rem_size: impl Into<Pixels>) {
860 self.window.rem_size = rem_size.into();
861 }
862
863 /// The line height associated with the current text style.
864 pub fn line_height(&self) -> Pixels {
865 let rem_size = self.rem_size();
866 let text_style = self.text_style();
867 text_style
868 .line_height
869 .to_pixels(text_style.font_size, rem_size)
870 }
871
872 /// Call to prevent the default action of an event. Currently only used to prevent
873 /// parent elements from becoming focused on mouse down.
874 pub fn prevent_default(&mut self) {
875 self.window.default_prevented = true;
876 }
877
878 /// Obtain whether default has been prevented for the event currently being dispatched.
879 pub fn default_prevented(&self) -> bool {
880 self.window.default_prevented
881 }
882
883 /// Register a mouse event listener on the window for the next frame. The type of event
884 /// is determined by the first parameter of the given listener. When the next frame is rendered
885 /// the listener will be cleared.
886 pub fn on_mouse_event<Event: 'static>(
887 &mut self,
888 mut handler: impl FnMut(&Event, DispatchPhase, &mut WindowContext) + 'static,
889 ) {
890 let view_id = self.parent_view_id().unwrap();
891 let order = self.window.next_frame.z_index_stack.clone();
892 self.window
893 .next_frame
894 .mouse_listeners
895 .entry(TypeId::of::<Event>())
896 .or_default()
897 .push((
898 order,
899 view_id,
900 Box::new(
901 move |event: &dyn Any, phase: DispatchPhase, cx: &mut WindowContext<'_>| {
902 handler(event.downcast_ref().unwrap(), phase, cx)
903 },
904 ),
905 ))
906 }
907
908 /// Register a key event listener on the window for the next frame. The type of event
909 /// is determined by the first parameter of the given listener. When the next frame is rendered
910 /// the listener will be cleared.
911 ///
912 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
913 /// a specific need to register a global listener.
914 pub fn on_key_event<Event: 'static>(
915 &mut self,
916 listener: impl Fn(&Event, DispatchPhase, &mut WindowContext) + 'static,
917 ) {
918 self.window.next_frame.dispatch_tree.on_key_event(Rc::new(
919 move |event: &dyn Any, phase, cx: &mut WindowContext<'_>| {
920 if let Some(event) = event.downcast_ref::<Event>() {
921 listener(event, phase, cx)
922 }
923 },
924 ));
925 }
926
927 /// Register an action listener on the window for the next frame. The type of action
928 /// is determined by the first parameter of the given listener. When the next frame is rendered
929 /// the listener will be cleared.
930 ///
931 /// This is a fairly low-level method, so prefer using action handlers on elements unless you have
932 /// a specific need to register a global listener.
933 pub fn on_action(
934 &mut self,
935 action_type: TypeId,
936 listener: impl Fn(&dyn Any, DispatchPhase, &mut WindowContext) + 'static,
937 ) {
938 self.window
939 .next_frame
940 .dispatch_tree
941 .on_action(action_type, Rc::new(listener));
942 }
943
944 pub fn is_action_available(&self, action: &dyn Action) -> bool {
945 let target = self
946 .focused()
947 .and_then(|focused_handle| {
948 self.window
949 .rendered_frame
950 .dispatch_tree
951 .focusable_node_id(focused_handle.id)
952 })
953 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
954 self.window
955 .rendered_frame
956 .dispatch_tree
957 .is_action_available(action, target)
958 }
959
960 /// The position of the mouse relative to the window.
961 pub fn mouse_position(&self) -> Point<Pixels> {
962 self.window.mouse_position
963 }
964
965 /// The current state of the keyboard's modifiers
966 pub fn modifiers(&self) -> Modifiers {
967 self.window.modifiers
968 }
969
970 pub fn set_cursor_style(&mut self, style: CursorStyle) {
971 self.window.requested_cursor_style = Some(style)
972 }
973
974 /// Called during painting to track which z-index is on top at each pixel position
975 pub fn add_opaque_layer(&mut self, bounds: Bounds<Pixels>) {
976 let stacking_order = self.window.next_frame.z_index_stack.clone();
977 let view_id = self.parent_view_id().unwrap();
978 self.window
979 .next_frame
980 .depth_map
981 .push((stacking_order, view_id, bounds));
982 }
983
984 /// Returns true if there is no opaque layer containing the given point
985 /// on top of the given level. Layers whose level is an extension of the
986 /// level are not considered to be on top of the level.
987 pub fn was_top_layer(&self, point: &Point<Pixels>, level: &StackingOrder) -> bool {
988 for (opaque_level, _, bounds) in self.window.rendered_frame.depth_map.iter() {
989 if level >= opaque_level {
990 break;
991 }
992
993 if bounds.contains(point) && !opaque_level.starts_with(level) {
994 return false;
995 }
996 }
997 true
998 }
999
1000 pub fn was_top_layer_under_active_drag(
1001 &self,
1002 point: &Point<Pixels>,
1003 level: &StackingOrder,
1004 ) -> bool {
1005 for (opaque_level, _, bounds) in self.window.rendered_frame.depth_map.iter() {
1006 if level >= opaque_level {
1007 break;
1008 }
1009 if opaque_level.starts_with(&[ACTIVE_DRAG_Z_INDEX]) {
1010 continue;
1011 }
1012
1013 if bounds.contains(point) && !opaque_level.starts_with(level) {
1014 return false;
1015 }
1016 }
1017 true
1018 }
1019
1020 /// Called during painting to get the current stacking order.
1021 pub fn stacking_order(&self) -> &StackingOrder {
1022 &self.window.next_frame.z_index_stack
1023 }
1024
1025 /// Paint one or more drop shadows into the scene for the next frame at the current z-index.
1026 pub fn paint_shadows(
1027 &mut self,
1028 bounds: Bounds<Pixels>,
1029 corner_radii: Corners<Pixels>,
1030 shadows: &[BoxShadow],
1031 ) {
1032 let scale_factor = self.scale_factor();
1033 let content_mask = self.content_mask();
1034 let view_id = self.parent_view_id().unwrap();
1035 let window = &mut *self.window;
1036 for shadow in shadows {
1037 let mut shadow_bounds = bounds;
1038 shadow_bounds.origin += shadow.offset;
1039 shadow_bounds.dilate(shadow.spread_radius);
1040 window.next_frame.scene.insert(
1041 &window.next_frame.z_index_stack,
1042 Shadow {
1043 view_id: view_id.as_u64() as u32,
1044 layer_id: 0,
1045 order: 0,
1046 bounds: shadow_bounds.scale(scale_factor),
1047 content_mask: content_mask.scale(scale_factor),
1048 corner_radii: corner_radii.scale(scale_factor),
1049 color: shadow.color,
1050 blur_radius: shadow.blur_radius.scale(scale_factor),
1051 },
1052 );
1053 }
1054 }
1055
1056 /// Paint one or more quads into the scene for the next frame at the current stacking context.
1057 /// Quads are colored rectangular regions with an optional background, border, and corner radius.
1058 /// see [`fill`], [`outline`], and [`quad`] to construct this type.
1059 pub fn paint_quad(&mut self, quad: PaintQuad) {
1060 let scale_factor = self.scale_factor();
1061 let content_mask = self.content_mask();
1062 let view_id = self.parent_view_id().unwrap();
1063
1064 let window = &mut *self.window;
1065 window.next_frame.scene.insert(
1066 &window.next_frame.z_index_stack,
1067 Quad {
1068 view_id: view_id.as_u64() as u32,
1069 layer_id: 0,
1070 order: 0,
1071 bounds: quad.bounds.scale(scale_factor),
1072 content_mask: content_mask.scale(scale_factor),
1073 background: quad.background,
1074 border_color: quad.border_color,
1075 corner_radii: quad.corner_radii.scale(scale_factor),
1076 border_widths: quad.border_widths.scale(scale_factor),
1077 },
1078 );
1079 }
1080
1081 /// Paint the given `Path` into the scene for the next frame at the current z-index.
1082 pub fn paint_path(&mut self, mut path: Path<Pixels>, color: impl Into<Hsla>) {
1083 let scale_factor = self.scale_factor();
1084 let content_mask = self.content_mask();
1085 let view_id = self.parent_view_id().unwrap();
1086
1087 path.content_mask = content_mask;
1088 path.color = color.into();
1089 path.view_id = view_id.as_u64() as u32;
1090 let window = &mut *self.window;
1091 window
1092 .next_frame
1093 .scene
1094 .insert(&window.next_frame.z_index_stack, path.scale(scale_factor));
1095 }
1096
1097 /// Paint an underline into the scene for the next frame at the current z-index.
1098 pub fn paint_underline(
1099 &mut self,
1100 origin: Point<Pixels>,
1101 width: Pixels,
1102 style: &UnderlineStyle,
1103 ) {
1104 let scale_factor = self.scale_factor();
1105 let height = if style.wavy {
1106 style.thickness * 3.
1107 } else {
1108 style.thickness
1109 };
1110 let bounds = Bounds {
1111 origin,
1112 size: size(width, height),
1113 };
1114 let content_mask = self.content_mask();
1115 let view_id = self.parent_view_id().unwrap();
1116
1117 let window = &mut *self.window;
1118 window.next_frame.scene.insert(
1119 &window.next_frame.z_index_stack,
1120 Underline {
1121 view_id: view_id.as_u64() as u32,
1122 layer_id: 0,
1123 order: 0,
1124 bounds: bounds.scale(scale_factor),
1125 content_mask: content_mask.scale(scale_factor),
1126 thickness: style.thickness.scale(scale_factor),
1127 color: style.color.unwrap_or_default(),
1128 wavy: style.wavy,
1129 },
1130 );
1131 }
1132
1133 /// Paint a monochrome (non-emoji) glyph into the scene for the next frame at the current z-index.
1134 /// The y component of the origin is the baseline of the glyph.
1135 pub fn paint_glyph(
1136 &mut self,
1137 origin: Point<Pixels>,
1138 font_id: FontId,
1139 glyph_id: GlyphId,
1140 font_size: Pixels,
1141 color: Hsla,
1142 ) -> Result<()> {
1143 let scale_factor = self.scale_factor();
1144 let glyph_origin = origin.scale(scale_factor);
1145 let subpixel_variant = Point {
1146 x: (glyph_origin.x.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
1147 y: (glyph_origin.y.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
1148 };
1149 let params = RenderGlyphParams {
1150 font_id,
1151 glyph_id,
1152 font_size,
1153 subpixel_variant,
1154 scale_factor,
1155 is_emoji: false,
1156 };
1157
1158 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
1159 if !raster_bounds.is_zero() {
1160 let tile =
1161 self.window
1162 .sprite_atlas
1163 .get_or_insert_with(¶ms.clone().into(), &mut || {
1164 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
1165 Ok((size, Cow::Owned(bytes)))
1166 })?;
1167 let bounds = Bounds {
1168 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
1169 size: tile.bounds.size.map(Into::into),
1170 };
1171 let content_mask = self.content_mask().scale(scale_factor);
1172 let view_id = self.parent_view_id().unwrap();
1173 let window = &mut *self.window;
1174 window.next_frame.scene.insert(
1175 &window.next_frame.z_index_stack,
1176 MonochromeSprite {
1177 view_id: view_id.as_u64() as u32,
1178 layer_id: 0,
1179 order: 0,
1180 bounds,
1181 content_mask,
1182 color,
1183 tile,
1184 },
1185 );
1186 }
1187 Ok(())
1188 }
1189
1190 /// Paint an emoji glyph into the scene for the next frame at the current z-index.
1191 /// The y component of the origin is the baseline of the glyph.
1192 pub fn paint_emoji(
1193 &mut self,
1194 origin: Point<Pixels>,
1195 font_id: FontId,
1196 glyph_id: GlyphId,
1197 font_size: Pixels,
1198 ) -> Result<()> {
1199 let scale_factor = self.scale_factor();
1200 let glyph_origin = origin.scale(scale_factor);
1201 let params = RenderGlyphParams {
1202 font_id,
1203 glyph_id,
1204 font_size,
1205 // We don't render emojis with subpixel variants.
1206 subpixel_variant: Default::default(),
1207 scale_factor,
1208 is_emoji: true,
1209 };
1210
1211 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
1212 if !raster_bounds.is_zero() {
1213 let tile =
1214 self.window
1215 .sprite_atlas
1216 .get_or_insert_with(¶ms.clone().into(), &mut || {
1217 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
1218 Ok((size, Cow::Owned(bytes)))
1219 })?;
1220 let bounds = Bounds {
1221 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
1222 size: tile.bounds.size.map(Into::into),
1223 };
1224 let content_mask = self.content_mask().scale(scale_factor);
1225 let view_id = self.parent_view_id().unwrap();
1226 let window = &mut *self.window;
1227
1228 window.next_frame.scene.insert(
1229 &window.next_frame.z_index_stack,
1230 PolychromeSprite {
1231 view_id: view_id.as_u64() as u32,
1232 layer_id: 0,
1233 order: 0,
1234 bounds,
1235 corner_radii: Default::default(),
1236 content_mask,
1237 tile,
1238 grayscale: false,
1239 },
1240 );
1241 }
1242 Ok(())
1243 }
1244
1245 /// Paint a monochrome SVG into the scene for the next frame at the current stacking context.
1246 pub fn paint_svg(
1247 &mut self,
1248 bounds: Bounds<Pixels>,
1249 path: SharedString,
1250 color: Hsla,
1251 ) -> Result<()> {
1252 let scale_factor = self.scale_factor();
1253 let bounds = bounds.scale(scale_factor);
1254 // Render the SVG at twice the size to get a higher quality result.
1255 let params = RenderSvgParams {
1256 path,
1257 size: bounds
1258 .size
1259 .map(|pixels| DevicePixels::from((pixels.0 * 2.).ceil() as i32)),
1260 };
1261
1262 let tile =
1263 self.window
1264 .sprite_atlas
1265 .get_or_insert_with(¶ms.clone().into(), &mut || {
1266 let bytes = self.svg_renderer.render(¶ms)?;
1267 Ok((params.size, Cow::Owned(bytes)))
1268 })?;
1269 let content_mask = self.content_mask().scale(scale_factor);
1270 let view_id = self.parent_view_id().unwrap();
1271
1272 let window = &mut *self.window;
1273 window.next_frame.scene.insert(
1274 &window.next_frame.z_index_stack,
1275 MonochromeSprite {
1276 view_id: view_id.as_u64() as u32,
1277 layer_id: 0,
1278 order: 0,
1279 bounds,
1280 content_mask,
1281 color,
1282 tile,
1283 },
1284 );
1285
1286 Ok(())
1287 }
1288
1289 /// Paint an image into the scene for the next frame at the current z-index.
1290 pub fn paint_image(
1291 &mut self,
1292 bounds: Bounds<Pixels>,
1293 corner_radii: Corners<Pixels>,
1294 data: Arc<ImageData>,
1295 grayscale: bool,
1296 ) -> Result<()> {
1297 let scale_factor = self.scale_factor();
1298 let bounds = bounds.scale(scale_factor);
1299 let params = RenderImageParams { image_id: data.id };
1300
1301 let tile = self
1302 .window
1303 .sprite_atlas
1304 .get_or_insert_with(¶ms.clone().into(), &mut || {
1305 Ok((data.size(), Cow::Borrowed(data.as_bytes())))
1306 })?;
1307 let content_mask = self.content_mask().scale(scale_factor);
1308 let corner_radii = corner_radii.scale(scale_factor);
1309 let view_id = self.parent_view_id().unwrap();
1310
1311 let window = &mut *self.window;
1312 window.next_frame.scene.insert(
1313 &window.next_frame.z_index_stack,
1314 PolychromeSprite {
1315 view_id: view_id.as_u64() as u32,
1316 layer_id: 0,
1317 order: 0,
1318 bounds,
1319 content_mask,
1320 corner_radii,
1321 tile,
1322 grayscale,
1323 },
1324 );
1325 Ok(())
1326 }
1327
1328 /// Paint a surface into the scene for the next frame at the current z-index.
1329 pub fn paint_surface(&mut self, bounds: Bounds<Pixels>, image_buffer: CVImageBuffer) {
1330 let scale_factor = self.scale_factor();
1331 let bounds = bounds.scale(scale_factor);
1332 let content_mask = self.content_mask().scale(scale_factor);
1333 let view_id = self.parent_view_id().unwrap();
1334 let window = &mut *self.window;
1335 window.next_frame.scene.insert(
1336 &window.next_frame.z_index_stack,
1337 Surface {
1338 view_id: view_id.as_u64() as u32,
1339 layer_id: 0,
1340 order: 0,
1341 bounds,
1342 content_mask,
1343 image_buffer,
1344 },
1345 );
1346 }
1347
1348 pub(crate) fn reuse_geometry(&mut self) {
1349 let view_id = self.parent_view_id().unwrap();
1350 let window = &mut self.window;
1351 let grafted_view_ids = window
1352 .next_frame
1353 .dispatch_tree
1354 .graft(view_id, &mut window.rendered_frame.dispatch_tree);
1355 for view_id in grafted_view_ids {
1356 assert!(window.next_frame.reused_views.insert(view_id));
1357 }
1358 }
1359
1360 /// Draw pixels to the display for this window based on the contents of its scene.
1361 pub(crate) fn draw(&mut self) {
1362 self.window.dirty = false;
1363 self.window.drawing = true;
1364
1365 #[cfg(any(test, feature = "test-support"))]
1366 {
1367 self.window.focus_invalidated = false;
1368 }
1369
1370 self.text_system().start_frame();
1371 self.window.platform_window.clear_input_handler();
1372 self.window.layout_engine.as_mut().unwrap().clear();
1373 self.window.next_frame.clear();
1374 let root_view = self.window.root_view.take().unwrap();
1375
1376 self.with_z_index(0, |cx| {
1377 cx.with_key_dispatch(Some(KeyContext::default()), None, |_, cx| {
1378 for (action_type, action_listeners) in &cx.app.global_action_listeners {
1379 for action_listener in action_listeners.iter().cloned() {
1380 cx.window.next_frame.dispatch_tree.on_action(
1381 *action_type,
1382 Rc::new(move |action: &dyn Any, phase, cx: &mut WindowContext<'_>| {
1383 action_listener(action, phase, cx)
1384 }),
1385 )
1386 }
1387 }
1388
1389 let available_space = cx.window.viewport_size.map(Into::into);
1390 root_view.draw(Point::default(), available_space, cx);
1391 })
1392 });
1393
1394 if let Some(active_drag) = self.app.active_drag.take() {
1395 self.with_z_index(ACTIVE_DRAG_Z_INDEX, |cx| {
1396 let offset = cx.mouse_position() - active_drag.cursor_offset;
1397 let available_space = size(AvailableSpace::MinContent, AvailableSpace::MinContent);
1398 active_drag.view.draw(offset, available_space, cx);
1399 });
1400 self.active_drag = Some(active_drag);
1401 } else if let Some(active_tooltip) = self.app.active_tooltip.take() {
1402 self.with_z_index(1, |cx| {
1403 let available_space = size(AvailableSpace::MinContent, AvailableSpace::MinContent);
1404 active_tooltip
1405 .view
1406 .draw(active_tooltip.cursor_offset, available_space, cx);
1407 });
1408 }
1409 self.window.dirty_views.clear();
1410
1411 self.window
1412 .next_frame
1413 .dispatch_tree
1414 .preserve_pending_keystrokes(
1415 &mut self.window.rendered_frame.dispatch_tree,
1416 self.window.focus,
1417 );
1418 self.window.next_frame.focus = self.window.focus;
1419 self.window.root_view = Some(root_view);
1420
1421 // Reuse mouse listeners that didn't change since the last frame.
1422 for (type_id, listeners) in &mut self.window.rendered_frame.mouse_listeners {
1423 let next_listeners = self
1424 .window
1425 .next_frame
1426 .mouse_listeners
1427 .entry(*type_id)
1428 .or_default();
1429 for (order, view_id, listener) in listeners.drain(..) {
1430 if self.window.next_frame.reused_views.contains(&view_id) {
1431 next_listeners.push((order, view_id, listener));
1432 }
1433 }
1434 }
1435
1436 // Reuse entries in the depth map that didn't change since the last frame.
1437 for (order, view_id, bounds) in self.window.rendered_frame.depth_map.drain(..) {
1438 if self.window.next_frame.reused_views.contains(&view_id) {
1439 self.window
1440 .next_frame
1441 .depth_map
1442 .push((order, view_id, bounds));
1443 }
1444 }
1445 self.window
1446 .next_frame
1447 .depth_map
1448 .sort_by(|a, b| a.0.cmp(&b.0));
1449
1450 // Retain element states for views that didn't change since the last frame.
1451 for (element_id, state) in self.window.rendered_frame.element_states.drain() {
1452 if self
1453 .window
1454 .next_frame
1455 .reused_views
1456 .contains(&state.parent_view_id)
1457 {
1458 self.window
1459 .next_frame
1460 .element_states
1461 .entry(element_id)
1462 .or_insert(state);
1463 }
1464 }
1465
1466 // Reuse geometry that didn't change since the last frame.
1467 self.window.next_frame.scene.insert_views_from_scene(
1468 &self.window.next_frame.reused_views,
1469 &mut self.window.rendered_frame.scene,
1470 );
1471 self.window.next_frame.scene.finish();
1472
1473 let previous_focus_path = self.window.rendered_frame.focus_path();
1474 mem::swap(&mut self.window.rendered_frame, &mut self.window.next_frame);
1475 let current_focus_path = self.window.rendered_frame.focus_path();
1476
1477 if previous_focus_path != current_focus_path {
1478 if !previous_focus_path.is_empty() && current_focus_path.is_empty() {
1479 self.window
1480 .blur_listeners
1481 .clone()
1482 .retain(&(), |listener| listener(self));
1483 }
1484
1485 let event = FocusEvent {
1486 previous_focus_path,
1487 current_focus_path,
1488 };
1489 self.window
1490 .focus_listeners
1491 .clone()
1492 .retain(&(), |listener| listener(&event, self));
1493 }
1494
1495 // Set the cursor only if we're the active window.
1496 let cursor_style = self
1497 .window
1498 .requested_cursor_style
1499 .take()
1500 .unwrap_or(CursorStyle::Arrow);
1501 if self.is_window_active() {
1502 self.platform.set_cursor_style(cursor_style);
1503 }
1504
1505 self.window.refreshing = false;
1506 self.window.drawing = false;
1507 ELEMENT_ARENA.with_borrow_mut(|element_arena| element_arena.clear());
1508
1509 self.window
1510 .platform_window
1511 .draw(&self.window.rendered_frame.scene);
1512 }
1513
1514 /// Dispatch a mouse or keyboard event on the window.
1515 pub fn dispatch_event(&mut self, event: InputEvent) -> bool {
1516 // Handlers may set this to false by calling `stop_propagation`.
1517 self.app.propagate_event = true;
1518 // Handlers may set this to true by calling `prevent_default`.
1519 self.window.default_prevented = false;
1520
1521 let event = match event {
1522 // Track the mouse position with our own state, since accessing the platform
1523 // API for the mouse position can only occur on the main thread.
1524 InputEvent::MouseMove(mouse_move) => {
1525 self.window.mouse_position = mouse_move.position;
1526 self.window.modifiers = mouse_move.modifiers;
1527 InputEvent::MouseMove(mouse_move)
1528 }
1529 InputEvent::MouseDown(mouse_down) => {
1530 self.window.mouse_position = mouse_down.position;
1531 self.window.modifiers = mouse_down.modifiers;
1532 InputEvent::MouseDown(mouse_down)
1533 }
1534 InputEvent::MouseUp(mouse_up) => {
1535 self.window.mouse_position = mouse_up.position;
1536 self.window.modifiers = mouse_up.modifiers;
1537 InputEvent::MouseUp(mouse_up)
1538 }
1539 InputEvent::MouseExited(mouse_exited) => {
1540 // todo!("Should we record that the mouse is outside of the window somehow? Or are these global pixels?")
1541 self.window.modifiers = mouse_exited.modifiers;
1542
1543 InputEvent::MouseExited(mouse_exited)
1544 }
1545 InputEvent::ModifiersChanged(modifiers_changed) => {
1546 self.window.modifiers = modifiers_changed.modifiers;
1547 InputEvent::ModifiersChanged(modifiers_changed)
1548 }
1549 InputEvent::ScrollWheel(scroll_wheel) => {
1550 self.window.mouse_position = scroll_wheel.position;
1551 self.window.modifiers = scroll_wheel.modifiers;
1552 InputEvent::ScrollWheel(scroll_wheel)
1553 }
1554 // Translate dragging and dropping of external files from the operating system
1555 // to internal drag and drop events.
1556 InputEvent::FileDrop(file_drop) => match file_drop {
1557 FileDropEvent::Entered { position, paths } => {
1558 self.window.mouse_position = position;
1559 if self.active_drag.is_none() {
1560 self.active_drag = Some(AnyDrag {
1561 value: Box::new(paths.clone()),
1562 view: self.new_view(|_| paths).into(),
1563 cursor_offset: position,
1564 });
1565 }
1566 InputEvent::MouseMove(MouseMoveEvent {
1567 position,
1568 pressed_button: Some(MouseButton::Left),
1569 modifiers: Modifiers::default(),
1570 })
1571 }
1572 FileDropEvent::Pending { position } => {
1573 self.window.mouse_position = position;
1574 InputEvent::MouseMove(MouseMoveEvent {
1575 position,
1576 pressed_button: Some(MouseButton::Left),
1577 modifiers: Modifiers::default(),
1578 })
1579 }
1580 FileDropEvent::Submit { position } => {
1581 self.activate(true);
1582 self.window.mouse_position = position;
1583 InputEvent::MouseUp(MouseUpEvent {
1584 button: MouseButton::Left,
1585 position,
1586 modifiers: Modifiers::default(),
1587 click_count: 1,
1588 })
1589 }
1590 FileDropEvent::Exited => InputEvent::MouseUp(MouseUpEvent {
1591 button: MouseButton::Left,
1592 position: Point::default(),
1593 modifiers: Modifiers::default(),
1594 click_count: 1,
1595 }),
1596 },
1597 InputEvent::KeyDown(_) | InputEvent::KeyUp(_) => event,
1598 };
1599
1600 if let Some(any_mouse_event) = event.mouse_event() {
1601 self.dispatch_mouse_event(any_mouse_event);
1602 } else if let Some(any_key_event) = event.keyboard_event() {
1603 self.dispatch_key_event(any_key_event);
1604 }
1605
1606 !self.app.propagate_event
1607 }
1608
1609 fn dispatch_mouse_event(&mut self, event: &dyn Any) {
1610 if let Some(mut handlers) = self
1611 .window
1612 .rendered_frame
1613 .mouse_listeners
1614 .remove(&event.type_id())
1615 {
1616 // Because handlers may add other handlers, we sort every time.
1617 handlers.sort_by(|(a, _, _), (b, _, _)| a.cmp(b));
1618
1619 // Capture phase, events bubble from back to front. Handlers for this phase are used for
1620 // special purposes, such as detecting events outside of a given Bounds.
1621 for (_, _, handler) in &mut handlers {
1622 handler(event, DispatchPhase::Capture, self);
1623 if !self.app.propagate_event {
1624 break;
1625 }
1626 }
1627
1628 // Bubble phase, where most normal handlers do their work.
1629 if self.app.propagate_event {
1630 for (_, _, handler) in handlers.iter_mut().rev() {
1631 handler(event, DispatchPhase::Bubble, self);
1632 if !self.app.propagate_event {
1633 break;
1634 }
1635 }
1636 }
1637
1638 self.window
1639 .rendered_frame
1640 .mouse_listeners
1641 .insert(event.type_id(), handlers);
1642 }
1643
1644 if self.app.propagate_event && self.has_active_drag() {
1645 if event.is::<MouseMoveEvent>() {
1646 // If this was a mouse move event, redraw the window so that the
1647 // active drag can follow the mouse cursor.
1648 self.refresh();
1649 } else if event.is::<MouseUpEvent>() {
1650 // If this was a mouse up event, cancel the active drag and redraw
1651 // the window.
1652 self.active_drag = None;
1653 self.refresh();
1654 }
1655 }
1656 }
1657
1658 fn dispatch_key_event(&mut self, event: &dyn Any) {
1659 let node_id = self
1660 .window
1661 .focus
1662 .and_then(|focus_id| {
1663 self.window
1664 .rendered_frame
1665 .dispatch_tree
1666 .focusable_node_id(focus_id)
1667 })
1668 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
1669
1670 let dispatch_path = self
1671 .window
1672 .rendered_frame
1673 .dispatch_tree
1674 .dispatch_path(node_id);
1675
1676 let mut actions: Vec<Box<dyn Action>> = Vec::new();
1677
1678 let mut context_stack: SmallVec<[KeyContext; 16]> = SmallVec::new();
1679 for node_id in &dispatch_path {
1680 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1681
1682 if let Some(context) = node.context.clone() {
1683 context_stack.push(context);
1684 }
1685 }
1686
1687 for node_id in dispatch_path.iter().rev() {
1688 // Match keystrokes
1689 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1690 if node.context.is_some() {
1691 if let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() {
1692 let mut new_actions = self
1693 .window
1694 .rendered_frame
1695 .dispatch_tree
1696 .dispatch_key(&key_down_event.keystroke, &context_stack);
1697 actions.append(&mut new_actions);
1698 }
1699
1700 context_stack.pop();
1701 }
1702 }
1703
1704 if !actions.is_empty() {
1705 self.clear_pending_keystrokes();
1706 }
1707
1708 self.propagate_event = true;
1709 for action in actions {
1710 self.dispatch_action_on_node(node_id, action.boxed_clone());
1711 if !self.propagate_event {
1712 self.dispatch_keystroke_observers(event, Some(action));
1713 return;
1714 }
1715 }
1716
1717 // Capture phase
1718 for node_id in &dispatch_path {
1719 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1720
1721 for key_listener in node.key_listeners.clone() {
1722 key_listener(event, DispatchPhase::Capture, self);
1723 if !self.propagate_event {
1724 return;
1725 }
1726 }
1727 }
1728
1729 // Bubble phase
1730 for node_id in dispatch_path.iter().rev() {
1731 // Handle low level key events
1732 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1733 for key_listener in node.key_listeners.clone() {
1734 key_listener(event, DispatchPhase::Bubble, self);
1735 if !self.propagate_event {
1736 return;
1737 }
1738 }
1739 }
1740
1741 self.dispatch_keystroke_observers(event, None);
1742 }
1743
1744 pub fn has_pending_keystrokes(&self) -> bool {
1745 self.window
1746 .rendered_frame
1747 .dispatch_tree
1748 .has_pending_keystrokes()
1749 }
1750
1751 fn dispatch_action_on_node(&mut self, node_id: DispatchNodeId, action: Box<dyn Action>) {
1752 let dispatch_path = self
1753 .window
1754 .rendered_frame
1755 .dispatch_tree
1756 .dispatch_path(node_id);
1757
1758 // Capture phase
1759 for node_id in &dispatch_path {
1760 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1761 for DispatchActionListener {
1762 action_type,
1763 listener,
1764 } in node.action_listeners.clone()
1765 {
1766 let any_action = action.as_any();
1767 if action_type == any_action.type_id() {
1768 listener(any_action, DispatchPhase::Capture, self);
1769 if !self.propagate_event {
1770 return;
1771 }
1772 }
1773 }
1774 }
1775 // Bubble phase
1776 for node_id in dispatch_path.iter().rev() {
1777 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
1778 for DispatchActionListener {
1779 action_type,
1780 listener,
1781 } in node.action_listeners.clone()
1782 {
1783 let any_action = action.as_any();
1784 if action_type == any_action.type_id() {
1785 self.propagate_event = false; // Actions stop propagation by default during the bubble phase
1786 listener(any_action, DispatchPhase::Bubble, self);
1787 if !self.propagate_event {
1788 return;
1789 }
1790 }
1791 }
1792 }
1793 }
1794
1795 /// Register the given handler to be invoked whenever the global of the given type
1796 /// is updated.
1797 pub fn observe_global<G: 'static>(
1798 &mut self,
1799 f: impl Fn(&mut WindowContext<'_>) + 'static,
1800 ) -> Subscription {
1801 let window_handle = self.window.handle;
1802 let (subscription, activate) = self.global_observers.insert(
1803 TypeId::of::<G>(),
1804 Box::new(move |cx| window_handle.update(cx, |_, cx| f(cx)).is_ok()),
1805 );
1806 self.app.defer(move |_| activate());
1807 subscription
1808 }
1809
1810 pub fn activate_window(&self) {
1811 self.window.platform_window.activate();
1812 }
1813
1814 pub fn minimize_window(&self) {
1815 self.window.platform_window.minimize();
1816 }
1817
1818 pub fn toggle_full_screen(&self) {
1819 self.window.platform_window.toggle_full_screen();
1820 }
1821
1822 pub fn prompt(
1823 &self,
1824 level: PromptLevel,
1825 msg: &str,
1826 answers: &[&str],
1827 ) -> oneshot::Receiver<usize> {
1828 self.window.platform_window.prompt(level, msg, answers)
1829 }
1830
1831 pub fn available_actions(&self) -> Vec<Box<dyn Action>> {
1832 let node_id = self
1833 .window
1834 .focus
1835 .and_then(|focus_id| {
1836 self.window
1837 .rendered_frame
1838 .dispatch_tree
1839 .focusable_node_id(focus_id)
1840 })
1841 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
1842
1843 self.window
1844 .rendered_frame
1845 .dispatch_tree
1846 .available_actions(node_id)
1847 }
1848
1849 pub fn bindings_for_action(&self, action: &dyn Action) -> Vec<KeyBinding> {
1850 self.window
1851 .rendered_frame
1852 .dispatch_tree
1853 .bindings_for_action(
1854 action,
1855 &self.window.rendered_frame.dispatch_tree.context_stack,
1856 )
1857 }
1858
1859 pub fn bindings_for_action_in(
1860 &self,
1861 action: &dyn Action,
1862 focus_handle: &FocusHandle,
1863 ) -> Vec<KeyBinding> {
1864 let dispatch_tree = &self.window.rendered_frame.dispatch_tree;
1865
1866 let Some(node_id) = dispatch_tree.focusable_node_id(focus_handle.id) else {
1867 return vec![];
1868 };
1869 let context_stack = dispatch_tree
1870 .dispatch_path(node_id)
1871 .into_iter()
1872 .filter_map(|node_id| dispatch_tree.node(node_id).context.clone())
1873 .collect();
1874 dispatch_tree.bindings_for_action(action, &context_stack)
1875 }
1876
1877 pub fn listener_for<V: Render, E>(
1878 &self,
1879 view: &View<V>,
1880 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
1881 ) -> impl Fn(&E, &mut WindowContext) + 'static {
1882 let view = view.downgrade();
1883 move |e: &E, cx: &mut WindowContext| {
1884 view.update(cx, |view, cx| f(view, e, cx)).ok();
1885 }
1886 }
1887
1888 pub fn handler_for<V: Render>(
1889 &self,
1890 view: &View<V>,
1891 f: impl Fn(&mut V, &mut ViewContext<V>) + 'static,
1892 ) -> impl Fn(&mut WindowContext) {
1893 let view = view.downgrade();
1894 move |cx: &mut WindowContext| {
1895 view.update(cx, |view, cx| f(view, cx)).ok();
1896 }
1897 }
1898
1899 //========== ELEMENT RELATED FUNCTIONS ===========
1900 pub fn with_key_dispatch<R>(
1901 &mut self,
1902 context: Option<KeyContext>,
1903 focus_handle: Option<FocusHandle>,
1904 f: impl FnOnce(Option<FocusHandle>, &mut Self) -> R,
1905 ) -> R {
1906 let parent_view_id = self.parent_view_id();
1907 let window = &mut self.window;
1908 let focus_id = focus_handle.as_ref().map(|handle| handle.id);
1909 window
1910 .next_frame
1911 .dispatch_tree
1912 .push_node(context.clone(), focus_id, parent_view_id);
1913
1914 let result = f(focus_handle, self);
1915
1916 self.window.next_frame.dispatch_tree.pop_node();
1917
1918 result
1919 }
1920
1921 pub(crate) fn with_view_id<R>(
1922 &mut self,
1923 view_id: EntityId,
1924 f: impl FnOnce(&mut Self) -> R,
1925 ) -> R {
1926 self.window.next_frame.view_stack.push(view_id);
1927 let result = f(self);
1928 self.window.next_frame.view_stack.pop();
1929 result
1930 }
1931
1932 /// Update or initialize state for an element with the given id that lives across multiple
1933 /// frames. If an element with this id existed in the rendered frame, its state will be passed
1934 /// to the given closure. The state returned by the closure will be stored so it can be referenced
1935 /// when drawing the next frame.
1936 pub(crate) fn with_element_state<S, R>(
1937 &mut self,
1938 id: ElementId,
1939 f: impl FnOnce(Option<S>, &mut Self) -> (R, S),
1940 ) -> R
1941 where
1942 S: 'static,
1943 {
1944 self.with_element_id(Some(id), |cx| {
1945 let global_id = cx.window().element_id_stack.clone();
1946
1947 if let Some(any) = cx
1948 .window_mut()
1949 .next_frame
1950 .element_states
1951 .remove(&global_id)
1952 .or_else(|| {
1953 cx.window_mut()
1954 .rendered_frame
1955 .element_states
1956 .remove(&global_id)
1957 })
1958 {
1959 let ElementStateBox {
1960 inner,
1961 parent_view_id,
1962 #[cfg(debug_assertions)]
1963 type_name
1964 } = any;
1965 // Using the extra inner option to avoid needing to reallocate a new box.
1966 let mut state_box = inner
1967 .downcast::<Option<S>>()
1968 .map_err(|_| {
1969 #[cfg(debug_assertions)]
1970 {
1971 anyhow!(
1972 "invalid element state type for id, requested_type {:?}, actual type: {:?}",
1973 std::any::type_name::<S>(),
1974 type_name
1975 )
1976 }
1977
1978 #[cfg(not(debug_assertions))]
1979 {
1980 anyhow!(
1981 "invalid element state type for id, requested_type {:?}",
1982 std::any::type_name::<S>(),
1983 )
1984 }
1985 })
1986 .unwrap();
1987
1988 // Actual: Option<AnyElement> <- View
1989 // Requested: () <- AnyElemet
1990 let state = state_box
1991 .take()
1992 .expect("element state is already on the stack");
1993 let (result, state) = f(Some(state), cx);
1994 state_box.replace(state);
1995 cx.window_mut()
1996 .next_frame
1997 .element_states
1998 .insert(global_id, ElementStateBox {
1999 inner: state_box,
2000 parent_view_id,
2001 #[cfg(debug_assertions)]
2002 type_name
2003 });
2004 result
2005 } else {
2006 let (result, state) = f(None, cx);
2007 let parent_view_id = cx.parent_view_id().unwrap();
2008 cx.window_mut()
2009 .next_frame
2010 .element_states
2011 .insert(global_id,
2012 ElementStateBox {
2013 inner: Box::new(Some(state)),
2014 parent_view_id,
2015 #[cfg(debug_assertions)]
2016 type_name: std::any::type_name::<S>()
2017 }
2018
2019 );
2020 result
2021 }
2022 })
2023 }
2024
2025 fn parent_view_id(&self) -> Option<EntityId> {
2026 self.window.next_frame.view_stack.last().copied()
2027 }
2028
2029 /// Set an input handler, such as [`ElementInputHandler`][element_input_handler], which interfaces with the
2030 /// platform to receive textual input with proper integration with concerns such
2031 /// as IME interactions.
2032 ///
2033 /// [element_input_handler]: crate::ElementInputHandler
2034 pub fn handle_input(
2035 &mut self,
2036 focus_handle: &FocusHandle,
2037 input_handler: impl PlatformInputHandler,
2038 ) {
2039 if focus_handle.is_focused(self) {
2040 self.window
2041 .platform_window
2042 .set_input_handler(Box::new(input_handler));
2043 }
2044 }
2045
2046 pub fn on_window_should_close(&mut self, f: impl Fn(&mut WindowContext) -> bool + 'static) {
2047 let mut this = self.to_async();
2048 self.window
2049 .platform_window
2050 .on_should_close(Box::new(move || this.update(|_, cx| f(cx)).unwrap_or(true)))
2051 }
2052}
2053
2054impl Context for WindowContext<'_> {
2055 type Result<T> = T;
2056
2057 fn new_model<T>(&mut self, build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T) -> Model<T>
2058 where
2059 T: 'static,
2060 {
2061 let slot = self.app.entities.reserve();
2062 let model = build_model(&mut ModelContext::new(&mut *self.app, slot.downgrade()));
2063 self.entities.insert(slot, model)
2064 }
2065
2066 fn update_model<T: 'static, R>(
2067 &mut self,
2068 model: &Model<T>,
2069 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
2070 ) -> R {
2071 let mut entity = self.entities.lease(model);
2072 let result = update(
2073 &mut *entity,
2074 &mut ModelContext::new(&mut *self.app, model.downgrade()),
2075 );
2076 self.entities.end_lease(entity);
2077 result
2078 }
2079
2080 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
2081 where
2082 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
2083 {
2084 if window == self.window.handle {
2085 let root_view = self.window.root_view.clone().unwrap();
2086 Ok(update(root_view, self))
2087 } else {
2088 window.update(self.app, update)
2089 }
2090 }
2091
2092 fn read_model<T, R>(
2093 &self,
2094 handle: &Model<T>,
2095 read: impl FnOnce(&T, &AppContext) -> R,
2096 ) -> Self::Result<R>
2097 where
2098 T: 'static,
2099 {
2100 let entity = self.entities.read(handle);
2101 read(entity, &*self.app)
2102 }
2103
2104 fn read_window<T, R>(
2105 &self,
2106 window: &WindowHandle<T>,
2107 read: impl FnOnce(View<T>, &AppContext) -> R,
2108 ) -> Result<R>
2109 where
2110 T: 'static,
2111 {
2112 if window.any_handle == self.window.handle {
2113 let root_view = self
2114 .window
2115 .root_view
2116 .clone()
2117 .unwrap()
2118 .downcast::<T>()
2119 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
2120 Ok(read(root_view, self))
2121 } else {
2122 self.app.read_window(window, read)
2123 }
2124 }
2125}
2126
2127impl VisualContext for WindowContext<'_> {
2128 fn new_view<V>(
2129 &mut self,
2130 build_view_state: impl FnOnce(&mut ViewContext<'_, V>) -> V,
2131 ) -> Self::Result<View<V>>
2132 where
2133 V: 'static + Render,
2134 {
2135 let slot = self.app.entities.reserve();
2136 let view = View {
2137 model: slot.clone(),
2138 };
2139 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
2140 let entity = build_view_state(&mut cx);
2141 cx.entities.insert(slot, entity);
2142
2143 cx.new_view_observers
2144 .clone()
2145 .retain(&TypeId::of::<V>(), |observer| {
2146 let any_view = AnyView::from(view.clone());
2147 (observer)(any_view, self);
2148 true
2149 });
2150
2151 view
2152 }
2153
2154 /// Update the given view. Prefer calling `View::update` instead, which calls this method.
2155 fn update_view<T: 'static, R>(
2156 &mut self,
2157 view: &View<T>,
2158 update: impl FnOnce(&mut T, &mut ViewContext<'_, T>) -> R,
2159 ) -> Self::Result<R> {
2160 let mut lease = self.app.entities.lease(&view.model);
2161 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, view);
2162 let result = update(&mut *lease, &mut cx);
2163 cx.app.entities.end_lease(lease);
2164 result
2165 }
2166
2167 fn replace_root_view<V>(
2168 &mut self,
2169 build_view: impl FnOnce(&mut ViewContext<'_, V>) -> V,
2170 ) -> Self::Result<View<V>>
2171 where
2172 V: 'static + Render,
2173 {
2174 let view = self.new_view(build_view);
2175 self.window.root_view = Some(view.clone().into());
2176 self.refresh();
2177 view
2178 }
2179
2180 fn focus_view<V: crate::FocusableView>(&mut self, view: &View<V>) -> Self::Result<()> {
2181 self.update_view(view, |view, cx| {
2182 view.focus_handle(cx).clone().focus(cx);
2183 })
2184 }
2185
2186 fn dismiss_view<V>(&mut self, view: &View<V>) -> Self::Result<()>
2187 where
2188 V: ManagedView,
2189 {
2190 self.update_view(view, |_, cx| cx.emit(DismissEvent))
2191 }
2192}
2193
2194impl<'a> std::ops::Deref for WindowContext<'a> {
2195 type Target = AppContext;
2196
2197 fn deref(&self) -> &Self::Target {
2198 self.app
2199 }
2200}
2201
2202impl<'a> std::ops::DerefMut for WindowContext<'a> {
2203 fn deref_mut(&mut self) -> &mut Self::Target {
2204 self.app
2205 }
2206}
2207
2208impl<'a> Borrow<AppContext> for WindowContext<'a> {
2209 fn borrow(&self) -> &AppContext {
2210 self.app
2211 }
2212}
2213
2214impl<'a> BorrowMut<AppContext> for WindowContext<'a> {
2215 fn borrow_mut(&mut self) -> &mut AppContext {
2216 self.app
2217 }
2218}
2219
2220pub trait BorrowWindow: BorrowMut<Window> + BorrowMut<AppContext> {
2221 fn app_mut(&mut self) -> &mut AppContext {
2222 self.borrow_mut()
2223 }
2224
2225 fn app(&self) -> &AppContext {
2226 self.borrow()
2227 }
2228
2229 fn window(&self) -> &Window {
2230 self.borrow()
2231 }
2232
2233 fn window_mut(&mut self) -> &mut Window {
2234 self.borrow_mut()
2235 }
2236
2237 /// Pushes the given element id onto the global stack and invokes the given closure
2238 /// with a `GlobalElementId`, which disambiguates the given id in the context of its ancestor
2239 /// ids. Because elements are discarded and recreated on each frame, the `GlobalElementId` is
2240 /// used to associate state with identified elements across separate frames.
2241 fn with_element_id<R>(
2242 &mut self,
2243 id: Option<impl Into<ElementId>>,
2244 f: impl FnOnce(&mut Self) -> R,
2245 ) -> R {
2246 if let Some(id) = id.map(Into::into) {
2247 let window = self.window_mut();
2248 window.element_id_stack.push(id);
2249 let result = f(self);
2250 let window: &mut Window = self.borrow_mut();
2251 window.element_id_stack.pop();
2252 result
2253 } else {
2254 f(self)
2255 }
2256 }
2257
2258 /// Invoke the given function with the given content mask after intersecting it
2259 /// with the current mask.
2260 fn with_content_mask<R>(
2261 &mut self,
2262 mask: Option<ContentMask<Pixels>>,
2263 f: impl FnOnce(&mut Self) -> R,
2264 ) -> R {
2265 if let Some(mask) = mask {
2266 let mask = mask.intersect(&self.content_mask());
2267 self.window_mut().next_frame.content_mask_stack.push(mask);
2268 let result = f(self);
2269 self.window_mut().next_frame.content_mask_stack.pop();
2270 result
2271 } else {
2272 f(self)
2273 }
2274 }
2275
2276 /// Invoke the given function with the content mask reset to that
2277 /// of the window.
2278 fn break_content_mask<R>(&mut self, f: impl FnOnce(&mut Self) -> R) -> R {
2279 let mask = ContentMask {
2280 bounds: Bounds {
2281 origin: Point::default(),
2282 size: self.window().viewport_size,
2283 },
2284 };
2285 let new_stacking_order_id =
2286 post_inc(&mut self.window_mut().next_frame.next_stacking_order_id);
2287 let old_stacking_order = mem::take(&mut self.window_mut().next_frame.z_index_stack);
2288 self.window_mut().next_frame.z_index_stack.id = new_stacking_order_id;
2289 self.window_mut().next_frame.content_mask_stack.push(mask);
2290 let result = f(self);
2291 self.window_mut().next_frame.content_mask_stack.pop();
2292 self.window_mut().next_frame.z_index_stack = old_stacking_order;
2293 result
2294 }
2295
2296 /// Called during painting to invoke the given closure in a new stacking context. The given
2297 /// z-index is interpreted relative to the previous call to `stack`.
2298 fn with_z_index<R>(&mut self, z_index: u8, f: impl FnOnce(&mut Self) -> R) -> R {
2299 let new_stacking_order_id =
2300 post_inc(&mut self.window_mut().next_frame.next_stacking_order_id);
2301 let old_stacking_order_id = mem::replace(
2302 &mut self.window_mut().next_frame.z_index_stack.id,
2303 new_stacking_order_id,
2304 );
2305 self.window_mut().next_frame.z_index_stack.id = new_stacking_order_id;
2306 self.window_mut().next_frame.z_index_stack.push(z_index);
2307 let result = f(self);
2308 self.window_mut().next_frame.z_index_stack.id = old_stacking_order_id;
2309 self.window_mut().next_frame.z_index_stack.pop();
2310 result
2311 }
2312
2313 /// Update the global element offset relative to the current offset. This is used to implement
2314 /// scrolling.
2315 fn with_element_offset<R>(
2316 &mut self,
2317 offset: Point<Pixels>,
2318 f: impl FnOnce(&mut Self) -> R,
2319 ) -> R {
2320 if offset.is_zero() {
2321 return f(self);
2322 };
2323
2324 let abs_offset = self.element_offset() + offset;
2325 self.with_absolute_element_offset(abs_offset, f)
2326 }
2327
2328 /// Update the global element offset based on the given offset. This is used to implement
2329 /// drag handles and other manual painting of elements.
2330 fn with_absolute_element_offset<R>(
2331 &mut self,
2332 offset: Point<Pixels>,
2333 f: impl FnOnce(&mut Self) -> R,
2334 ) -> R {
2335 self.window_mut()
2336 .next_frame
2337 .element_offset_stack
2338 .push(offset);
2339 let result = f(self);
2340 self.window_mut().next_frame.element_offset_stack.pop();
2341 result
2342 }
2343
2344 /// Obtain the current element offset.
2345 fn element_offset(&self) -> Point<Pixels> {
2346 self.window()
2347 .next_frame
2348 .element_offset_stack
2349 .last()
2350 .copied()
2351 .unwrap_or_default()
2352 }
2353
2354 /// Obtain the current content mask.
2355 fn content_mask(&self) -> ContentMask<Pixels> {
2356 self.window()
2357 .next_frame
2358 .content_mask_stack
2359 .last()
2360 .cloned()
2361 .unwrap_or_else(|| ContentMask {
2362 bounds: Bounds {
2363 origin: Point::default(),
2364 size: self.window().viewport_size,
2365 },
2366 })
2367 }
2368
2369 /// The size of an em for the base font of the application. Adjusting this value allows the
2370 /// UI to scale, just like zooming a web page.
2371 fn rem_size(&self) -> Pixels {
2372 self.window().rem_size
2373 }
2374}
2375
2376impl Borrow<Window> for WindowContext<'_> {
2377 fn borrow(&self) -> &Window {
2378 self.window
2379 }
2380}
2381
2382impl BorrowMut<Window> for WindowContext<'_> {
2383 fn borrow_mut(&mut self) -> &mut Window {
2384 self.window
2385 }
2386}
2387
2388impl<T> BorrowWindow for T where T: BorrowMut<AppContext> + BorrowMut<Window> {}
2389
2390pub struct ViewContext<'a, V> {
2391 window_cx: WindowContext<'a>,
2392 view: &'a View<V>,
2393}
2394
2395impl<V> Borrow<AppContext> for ViewContext<'_, V> {
2396 fn borrow(&self) -> &AppContext {
2397 &*self.window_cx.app
2398 }
2399}
2400
2401impl<V> BorrowMut<AppContext> for ViewContext<'_, V> {
2402 fn borrow_mut(&mut self) -> &mut AppContext {
2403 &mut *self.window_cx.app
2404 }
2405}
2406
2407impl<V> Borrow<Window> for ViewContext<'_, V> {
2408 fn borrow(&self) -> &Window {
2409 &*self.window_cx.window
2410 }
2411}
2412
2413impl<V> BorrowMut<Window> for ViewContext<'_, V> {
2414 fn borrow_mut(&mut self) -> &mut Window {
2415 &mut *self.window_cx.window
2416 }
2417}
2418
2419impl<'a, V: 'static> ViewContext<'a, V> {
2420 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window, view: &'a View<V>) -> Self {
2421 Self {
2422 window_cx: WindowContext::new(app, window),
2423 view,
2424 }
2425 }
2426
2427 pub fn entity_id(&self) -> EntityId {
2428 self.view.entity_id()
2429 }
2430
2431 pub fn view(&self) -> &View<V> {
2432 self.view
2433 }
2434
2435 pub fn model(&self) -> &Model<V> {
2436 &self.view.model
2437 }
2438
2439 /// Access the underlying window context.
2440 pub fn window_context(&mut self) -> &mut WindowContext<'a> {
2441 &mut self.window_cx
2442 }
2443
2444 pub fn on_next_frame(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static)
2445 where
2446 V: 'static,
2447 {
2448 let view = self.view().clone();
2449 self.window_cx.on_next_frame(move |cx| view.update(cx, f));
2450 }
2451
2452 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
2453 /// that are currently on the stack to be returned to the app.
2454 pub fn defer(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static) {
2455 let view = self.view().downgrade();
2456 self.window_cx.defer(move |cx| {
2457 view.update(cx, f).ok();
2458 });
2459 }
2460
2461 pub fn observe<V2, E>(
2462 &mut self,
2463 entity: &E,
2464 mut on_notify: impl FnMut(&mut V, E, &mut ViewContext<'_, V>) + 'static,
2465 ) -> Subscription
2466 where
2467 V2: 'static,
2468 V: 'static,
2469 E: Entity<V2>,
2470 {
2471 let view = self.view().downgrade();
2472 let entity_id = entity.entity_id();
2473 let entity = entity.downgrade();
2474 let window_handle = self.window.handle;
2475 let (subscription, activate) = self.app.observers.insert(
2476 entity_id,
2477 Box::new(move |cx| {
2478 window_handle
2479 .update(cx, |_, cx| {
2480 if let Some(handle) = E::upgrade_from(&entity) {
2481 view.update(cx, |this, cx| on_notify(this, handle, cx))
2482 .is_ok()
2483 } else {
2484 false
2485 }
2486 })
2487 .unwrap_or(false)
2488 }),
2489 );
2490 self.app.defer(move |_| activate());
2491 subscription
2492 }
2493
2494 pub fn subscribe<V2, E, Evt>(
2495 &mut self,
2496 entity: &E,
2497 mut on_event: impl FnMut(&mut V, E, &Evt, &mut ViewContext<'_, V>) + 'static,
2498 ) -> Subscription
2499 where
2500 V2: EventEmitter<Evt>,
2501 E: Entity<V2>,
2502 Evt: 'static,
2503 {
2504 let view = self.view().downgrade();
2505 let entity_id = entity.entity_id();
2506 let handle = entity.downgrade();
2507 let window_handle = self.window.handle;
2508 let (subscription, activate) = self.app.event_listeners.insert(
2509 entity_id,
2510 (
2511 TypeId::of::<Evt>(),
2512 Box::new(move |event, cx| {
2513 window_handle
2514 .update(cx, |_, cx| {
2515 if let Some(handle) = E::upgrade_from(&handle) {
2516 let event = event.downcast_ref().expect("invalid event type");
2517 view.update(cx, |this, cx| on_event(this, handle, event, cx))
2518 .is_ok()
2519 } else {
2520 false
2521 }
2522 })
2523 .unwrap_or(false)
2524 }),
2525 ),
2526 );
2527 self.app.defer(move |_| activate());
2528 subscription
2529 }
2530
2531 /// Register a callback to be invoked when the view is released.
2532 ///
2533 /// The callback receives a handle to the view's window. This handle may be
2534 /// invalid, if the window was closed before the view was released.
2535 pub fn on_release(
2536 &mut self,
2537 on_release: impl FnOnce(&mut V, AnyWindowHandle, &mut AppContext) + 'static,
2538 ) -> Subscription {
2539 let window_handle = self.window.handle;
2540 let (subscription, activate) = self.app.release_listeners.insert(
2541 self.view.model.entity_id,
2542 Box::new(move |this, cx| {
2543 let this = this.downcast_mut().expect("invalid entity type");
2544 on_release(this, window_handle, cx)
2545 }),
2546 );
2547 activate();
2548 subscription
2549 }
2550
2551 pub fn observe_release<V2, E>(
2552 &mut self,
2553 entity: &E,
2554 mut on_release: impl FnMut(&mut V, &mut V2, &mut ViewContext<'_, V>) + 'static,
2555 ) -> Subscription
2556 where
2557 V: 'static,
2558 V2: 'static,
2559 E: Entity<V2>,
2560 {
2561 let view = self.view().downgrade();
2562 let entity_id = entity.entity_id();
2563 let window_handle = self.window.handle;
2564 let (subscription, activate) = self.app.release_listeners.insert(
2565 entity_id,
2566 Box::new(move |entity, cx| {
2567 let entity = entity.downcast_mut().expect("invalid entity type");
2568 let _ = window_handle.update(cx, |_, cx| {
2569 view.update(cx, |this, cx| on_release(this, entity, cx))
2570 });
2571 }),
2572 );
2573 activate();
2574 subscription
2575 }
2576
2577 pub fn notify(&mut self) {
2578 for view_id in self
2579 .window
2580 .rendered_frame
2581 .dispatch_tree
2582 .view_path(self.view.entity_id())
2583 {
2584 if !self.window.dirty_views.insert(view_id) {
2585 break;
2586 }
2587 }
2588
2589 if !self.window.drawing {
2590 self.window_cx.window.dirty = true;
2591 self.window_cx.app.push_effect(Effect::Notify {
2592 emitter: self.view.model.entity_id,
2593 });
2594 }
2595 }
2596
2597 pub fn observe_window_bounds(
2598 &mut self,
2599 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2600 ) -> Subscription {
2601 let view = self.view.downgrade();
2602 let (subscription, activate) = self.window.bounds_observers.insert(
2603 (),
2604 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
2605 );
2606 activate();
2607 subscription
2608 }
2609
2610 pub fn observe_window_activation(
2611 &mut self,
2612 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2613 ) -> Subscription {
2614 let view = self.view.downgrade();
2615 let (subscription, activate) = self.window.activation_observers.insert(
2616 (),
2617 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
2618 );
2619 activate();
2620 subscription
2621 }
2622
2623 /// Register a listener to be called when the given focus handle receives focus.
2624 /// Returns a subscription and persists until the subscription is dropped.
2625 pub fn on_focus(
2626 &mut self,
2627 handle: &FocusHandle,
2628 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2629 ) -> Subscription {
2630 let view = self.view.downgrade();
2631 let focus_id = handle.id;
2632 let (subscription, activate) = self.window.focus_listeners.insert(
2633 (),
2634 Box::new(move |event, cx| {
2635 view.update(cx, |view, cx| {
2636 if event.previous_focus_path.last() != Some(&focus_id)
2637 && event.current_focus_path.last() == Some(&focus_id)
2638 {
2639 listener(view, cx)
2640 }
2641 })
2642 .is_ok()
2643 }),
2644 );
2645 self.app.defer(move |_| activate());
2646 subscription
2647 }
2648
2649 /// Register a listener to be called when the given focus handle or one of its descendants receives focus.
2650 /// Returns a subscription and persists until the subscription is dropped.
2651 pub fn on_focus_in(
2652 &mut self,
2653 handle: &FocusHandle,
2654 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2655 ) -> Subscription {
2656 let view = self.view.downgrade();
2657 let focus_id = handle.id;
2658 let (subscription, activate) = self.window.focus_listeners.insert(
2659 (),
2660 Box::new(move |event, cx| {
2661 view.update(cx, |view, cx| {
2662 if !event.previous_focus_path.contains(&focus_id)
2663 && event.current_focus_path.contains(&focus_id)
2664 {
2665 listener(view, cx)
2666 }
2667 })
2668 .is_ok()
2669 }),
2670 );
2671 self.app.defer(move |_| activate());
2672 subscription
2673 }
2674
2675 /// Register a listener to be called when the given focus handle loses focus.
2676 /// Returns a subscription and persists until the subscription is dropped.
2677 pub fn on_blur(
2678 &mut self,
2679 handle: &FocusHandle,
2680 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2681 ) -> Subscription {
2682 let view = self.view.downgrade();
2683 let focus_id = handle.id;
2684 let (subscription, activate) = self.window.focus_listeners.insert(
2685 (),
2686 Box::new(move |event, cx| {
2687 view.update(cx, |view, cx| {
2688 if event.previous_focus_path.last() == Some(&focus_id)
2689 && event.current_focus_path.last() != Some(&focus_id)
2690 {
2691 listener(view, cx)
2692 }
2693 })
2694 .is_ok()
2695 }),
2696 );
2697 self.app.defer(move |_| activate());
2698 subscription
2699 }
2700
2701 /// Register a listener to be called when the window loses focus.
2702 /// Returns a subscription and persists until the subscription is dropped.
2703 pub fn on_blur_window(
2704 &mut self,
2705 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2706 ) -> Subscription {
2707 let view = self.view.downgrade();
2708 let (subscription, activate) = self.window.blur_listeners.insert(
2709 (),
2710 Box::new(move |cx| view.update(cx, |view, cx| listener(view, cx)).is_ok()),
2711 );
2712 activate();
2713 subscription
2714 }
2715
2716 /// Register a listener to be called when the given focus handle or one of its descendants loses focus.
2717 /// Returns a subscription and persists until the subscription is dropped.
2718 pub fn on_focus_out(
2719 &mut self,
2720 handle: &FocusHandle,
2721 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
2722 ) -> Subscription {
2723 let view = self.view.downgrade();
2724 let focus_id = handle.id;
2725 let (subscription, activate) = self.window.focus_listeners.insert(
2726 (),
2727 Box::new(move |event, cx| {
2728 view.update(cx, |view, cx| {
2729 if event.previous_focus_path.contains(&focus_id)
2730 && !event.current_focus_path.contains(&focus_id)
2731 {
2732 listener(view, cx)
2733 }
2734 })
2735 .is_ok()
2736 }),
2737 );
2738 self.app.defer(move |_| activate());
2739 subscription
2740 }
2741
2742 pub fn spawn<Fut, R>(
2743 &mut self,
2744 f: impl FnOnce(WeakView<V>, AsyncWindowContext) -> Fut,
2745 ) -> Task<R>
2746 where
2747 R: 'static,
2748 Fut: Future<Output = R> + 'static,
2749 {
2750 let view = self.view().downgrade();
2751 self.window_cx.spawn(|cx| f(view, cx))
2752 }
2753
2754 pub fn update_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
2755 where
2756 G: 'static,
2757 {
2758 let mut global = self.app.lease_global::<G>();
2759 let result = f(&mut global, self);
2760 self.app.end_global_lease(global);
2761 result
2762 }
2763
2764 pub fn observe_global<G: 'static>(
2765 &mut self,
2766 mut f: impl FnMut(&mut V, &mut ViewContext<'_, V>) + 'static,
2767 ) -> Subscription {
2768 let window_handle = self.window.handle;
2769 let view = self.view().downgrade();
2770 let (subscription, activate) = self.global_observers.insert(
2771 TypeId::of::<G>(),
2772 Box::new(move |cx| {
2773 window_handle
2774 .update(cx, |_, cx| view.update(cx, |view, cx| f(view, cx)).is_ok())
2775 .unwrap_or(false)
2776 }),
2777 );
2778 self.app.defer(move |_| activate());
2779 subscription
2780 }
2781
2782 pub fn on_mouse_event<Event: 'static>(
2783 &mut self,
2784 handler: impl Fn(&mut V, &Event, DispatchPhase, &mut ViewContext<V>) + 'static,
2785 ) {
2786 let handle = self.view().clone();
2787 self.window_cx.on_mouse_event(move |event, phase, cx| {
2788 handle.update(cx, |view, cx| {
2789 handler(view, event, phase, cx);
2790 })
2791 });
2792 }
2793
2794 pub fn on_key_event<Event: 'static>(
2795 &mut self,
2796 handler: impl Fn(&mut V, &Event, DispatchPhase, &mut ViewContext<V>) + 'static,
2797 ) {
2798 let handle = self.view().clone();
2799 self.window_cx.on_key_event(move |event, phase, cx| {
2800 handle.update(cx, |view, cx| {
2801 handler(view, event, phase, cx);
2802 })
2803 });
2804 }
2805
2806 pub fn on_action(
2807 &mut self,
2808 action_type: TypeId,
2809 listener: impl Fn(&mut V, &dyn Any, DispatchPhase, &mut ViewContext<V>) + 'static,
2810 ) {
2811 let handle = self.view().clone();
2812 self.window_cx
2813 .on_action(action_type, move |action, phase, cx| {
2814 handle.update(cx, |view, cx| {
2815 listener(view, action, phase, cx);
2816 })
2817 });
2818 }
2819
2820 pub fn emit<Evt>(&mut self, event: Evt)
2821 where
2822 Evt: 'static,
2823 V: EventEmitter<Evt>,
2824 {
2825 let emitter = self.view.model.entity_id;
2826 self.app.push_effect(Effect::Emit {
2827 emitter,
2828 event_type: TypeId::of::<Evt>(),
2829 event: Box::new(event),
2830 });
2831 }
2832
2833 pub fn focus_self(&mut self)
2834 where
2835 V: FocusableView,
2836 {
2837 self.defer(|view, cx| view.focus_handle(cx).focus(cx))
2838 }
2839
2840 pub fn listener<E>(
2841 &self,
2842 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
2843 ) -> impl Fn(&E, &mut WindowContext) + 'static {
2844 let view = self.view().downgrade();
2845 move |e: &E, cx: &mut WindowContext| {
2846 view.update(cx, |view, cx| f(view, e, cx)).ok();
2847 }
2848 }
2849}
2850
2851impl<V> Context for ViewContext<'_, V> {
2852 type Result<U> = U;
2853
2854 fn new_model<T: 'static>(
2855 &mut self,
2856 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
2857 ) -> Model<T> {
2858 self.window_cx.new_model(build_model)
2859 }
2860
2861 fn update_model<T: 'static, R>(
2862 &mut self,
2863 model: &Model<T>,
2864 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
2865 ) -> R {
2866 self.window_cx.update_model(model, update)
2867 }
2868
2869 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
2870 where
2871 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
2872 {
2873 self.window_cx.update_window(window, update)
2874 }
2875
2876 fn read_model<T, R>(
2877 &self,
2878 handle: &Model<T>,
2879 read: impl FnOnce(&T, &AppContext) -> R,
2880 ) -> Self::Result<R>
2881 where
2882 T: 'static,
2883 {
2884 self.window_cx.read_model(handle, read)
2885 }
2886
2887 fn read_window<T, R>(
2888 &self,
2889 window: &WindowHandle<T>,
2890 read: impl FnOnce(View<T>, &AppContext) -> R,
2891 ) -> Result<R>
2892 where
2893 T: 'static,
2894 {
2895 self.window_cx.read_window(window, read)
2896 }
2897}
2898
2899impl<V: 'static> VisualContext for ViewContext<'_, V> {
2900 fn new_view<W: Render + 'static>(
2901 &mut self,
2902 build_view_state: impl FnOnce(&mut ViewContext<'_, W>) -> W,
2903 ) -> Self::Result<View<W>> {
2904 self.window_cx.new_view(build_view_state)
2905 }
2906
2907 fn update_view<V2: 'static, R>(
2908 &mut self,
2909 view: &View<V2>,
2910 update: impl FnOnce(&mut V2, &mut ViewContext<'_, V2>) -> R,
2911 ) -> Self::Result<R> {
2912 self.window_cx.update_view(view, update)
2913 }
2914
2915 fn replace_root_view<W>(
2916 &mut self,
2917 build_view: impl FnOnce(&mut ViewContext<'_, W>) -> W,
2918 ) -> Self::Result<View<W>>
2919 where
2920 W: 'static + Render,
2921 {
2922 self.window_cx.replace_root_view(build_view)
2923 }
2924
2925 fn focus_view<W: FocusableView>(&mut self, view: &View<W>) -> Self::Result<()> {
2926 self.window_cx.focus_view(view)
2927 }
2928
2929 fn dismiss_view<W: ManagedView>(&mut self, view: &View<W>) -> Self::Result<()> {
2930 self.window_cx.dismiss_view(view)
2931 }
2932}
2933
2934impl<'a, V> std::ops::Deref for ViewContext<'a, V> {
2935 type Target = WindowContext<'a>;
2936
2937 fn deref(&self) -> &Self::Target {
2938 &self.window_cx
2939 }
2940}
2941
2942impl<'a, V> std::ops::DerefMut for ViewContext<'a, V> {
2943 fn deref_mut(&mut self) -> &mut Self::Target {
2944 &mut self.window_cx
2945 }
2946}
2947
2948// #[derive(Clone, Copy, Eq, PartialEq, Hash)]
2949slotmap::new_key_type! { pub struct WindowId; }
2950
2951impl WindowId {
2952 pub fn as_u64(&self) -> u64 {
2953 self.0.as_ffi()
2954 }
2955}
2956
2957#[derive(Deref, DerefMut)]
2958pub struct WindowHandle<V> {
2959 #[deref]
2960 #[deref_mut]
2961 pub(crate) any_handle: AnyWindowHandle,
2962 state_type: PhantomData<V>,
2963}
2964
2965impl<V: 'static + Render> WindowHandle<V> {
2966 pub fn new(id: WindowId) -> Self {
2967 WindowHandle {
2968 any_handle: AnyWindowHandle {
2969 id,
2970 state_type: TypeId::of::<V>(),
2971 },
2972 state_type: PhantomData,
2973 }
2974 }
2975
2976 pub fn root<C>(&self, cx: &mut C) -> Result<View<V>>
2977 where
2978 C: Context,
2979 {
2980 Flatten::flatten(cx.update_window(self.any_handle, |root_view, _| {
2981 root_view
2982 .downcast::<V>()
2983 .map_err(|_| anyhow!("the type of the window's root view has changed"))
2984 }))
2985 }
2986
2987 pub fn update<C, R>(
2988 &self,
2989 cx: &mut C,
2990 update: impl FnOnce(&mut V, &mut ViewContext<'_, V>) -> R,
2991 ) -> Result<R>
2992 where
2993 C: Context,
2994 {
2995 cx.update_window(self.any_handle, |root_view, cx| {
2996 let view = root_view
2997 .downcast::<V>()
2998 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
2999 Ok(cx.update_view(&view, update))
3000 })?
3001 }
3002
3003 pub fn read<'a>(&self, cx: &'a AppContext) -> Result<&'a V> {
3004 let x = cx
3005 .windows
3006 .get(self.id)
3007 .and_then(|window| {
3008 window
3009 .as_ref()
3010 .and_then(|window| window.root_view.clone())
3011 .map(|root_view| root_view.downcast::<V>())
3012 })
3013 .ok_or_else(|| anyhow!("window not found"))?
3014 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
3015
3016 Ok(x.read(cx))
3017 }
3018
3019 pub fn read_with<C, R>(&self, cx: &C, read_with: impl FnOnce(&V, &AppContext) -> R) -> Result<R>
3020 where
3021 C: Context,
3022 {
3023 cx.read_window(self, |root_view, cx| read_with(root_view.read(cx), cx))
3024 }
3025
3026 pub fn root_view<C>(&self, cx: &C) -> Result<View<V>>
3027 where
3028 C: Context,
3029 {
3030 cx.read_window(self, |root_view, _cx| root_view.clone())
3031 }
3032
3033 pub fn is_active(&self, cx: &AppContext) -> Option<bool> {
3034 cx.windows
3035 .get(self.id)
3036 .and_then(|window| window.as_ref().map(|window| window.active))
3037 }
3038}
3039
3040impl<V> Copy for WindowHandle<V> {}
3041
3042impl<V> Clone for WindowHandle<V> {
3043 fn clone(&self) -> Self {
3044 *self
3045 }
3046}
3047
3048impl<V> PartialEq for WindowHandle<V> {
3049 fn eq(&self, other: &Self) -> bool {
3050 self.any_handle == other.any_handle
3051 }
3052}
3053
3054impl<V> Eq for WindowHandle<V> {}
3055
3056impl<V> Hash for WindowHandle<V> {
3057 fn hash<H: Hasher>(&self, state: &mut H) {
3058 self.any_handle.hash(state);
3059 }
3060}
3061
3062impl<V: 'static> From<WindowHandle<V>> for AnyWindowHandle {
3063 fn from(val: WindowHandle<V>) -> Self {
3064 val.any_handle
3065 }
3066}
3067
3068#[derive(Copy, Clone, PartialEq, Eq, Hash)]
3069pub struct AnyWindowHandle {
3070 pub(crate) id: WindowId,
3071 state_type: TypeId,
3072}
3073
3074impl AnyWindowHandle {
3075 pub fn window_id(&self) -> WindowId {
3076 self.id
3077 }
3078
3079 pub fn downcast<T: 'static>(&self) -> Option<WindowHandle<T>> {
3080 if TypeId::of::<T>() == self.state_type {
3081 Some(WindowHandle {
3082 any_handle: *self,
3083 state_type: PhantomData,
3084 })
3085 } else {
3086 None
3087 }
3088 }
3089
3090 pub fn update<C, R>(
3091 self,
3092 cx: &mut C,
3093 update: impl FnOnce(AnyView, &mut WindowContext<'_>) -> R,
3094 ) -> Result<R>
3095 where
3096 C: Context,
3097 {
3098 cx.update_window(self, update)
3099 }
3100
3101 pub fn read<T, C, R>(self, cx: &C, read: impl FnOnce(View<T>, &AppContext) -> R) -> Result<R>
3102 where
3103 C: Context,
3104 T: 'static,
3105 {
3106 let view = self
3107 .downcast::<T>()
3108 .context("the type of the window's root view has changed")?;
3109
3110 cx.read_window(&view, read)
3111 }
3112}
3113
3114// #[cfg(any(test, feature = "test-support"))]
3115// impl From<SmallVec<[u32; 16]>> for StackingOrder {
3116// fn from(small_vec: SmallVec<[u32; 16]>) -> Self {
3117// StackingOrder(small_vec)
3118// }
3119// }
3120
3121#[derive(Clone, Debug, Eq, PartialEq, Hash)]
3122pub enum ElementId {
3123 View(EntityId),
3124 Integer(usize),
3125 Name(SharedString),
3126 FocusHandle(FocusId),
3127 NamedInteger(SharedString, usize),
3128}
3129
3130impl ElementId {
3131 pub(crate) fn from_entity_id(entity_id: EntityId) -> Self {
3132 ElementId::View(entity_id)
3133 }
3134}
3135
3136impl TryInto<SharedString> for ElementId {
3137 type Error = anyhow::Error;
3138
3139 fn try_into(self) -> anyhow::Result<SharedString> {
3140 if let ElementId::Name(name) = self {
3141 Ok(name)
3142 } else {
3143 Err(anyhow!("element id is not string"))
3144 }
3145 }
3146}
3147
3148impl From<usize> for ElementId {
3149 fn from(id: usize) -> Self {
3150 ElementId::Integer(id)
3151 }
3152}
3153
3154impl From<i32> for ElementId {
3155 fn from(id: i32) -> Self {
3156 Self::Integer(id as usize)
3157 }
3158}
3159
3160impl From<SharedString> for ElementId {
3161 fn from(name: SharedString) -> Self {
3162 ElementId::Name(name)
3163 }
3164}
3165
3166impl From<&'static str> for ElementId {
3167 fn from(name: &'static str) -> Self {
3168 ElementId::Name(name.into())
3169 }
3170}
3171
3172impl<'a> From<&'a FocusHandle> for ElementId {
3173 fn from(handle: &'a FocusHandle) -> Self {
3174 ElementId::FocusHandle(handle.id)
3175 }
3176}
3177
3178impl From<(&'static str, EntityId)> for ElementId {
3179 fn from((name, id): (&'static str, EntityId)) -> Self {
3180 ElementId::NamedInteger(name.into(), id.as_u64() as usize)
3181 }
3182}
3183
3184impl From<(&'static str, usize)> for ElementId {
3185 fn from((name, id): (&'static str, usize)) -> Self {
3186 ElementId::NamedInteger(name.into(), id)
3187 }
3188}
3189
3190impl From<(&'static str, u64)> for ElementId {
3191 fn from((name, id): (&'static str, u64)) -> Self {
3192 ElementId::NamedInteger(name.into(), id as usize)
3193 }
3194}
3195
3196/// A rectangle, to be rendered on the screen by GPUI at the given position and size.
3197#[derive(Clone)]
3198pub struct PaintQuad {
3199 bounds: Bounds<Pixels>,
3200 corner_radii: Corners<Pixels>,
3201 background: Hsla,
3202 border_widths: Edges<Pixels>,
3203 border_color: Hsla,
3204}
3205
3206impl PaintQuad {
3207 /// Set the corner radii of the quad.
3208 pub fn corner_radii(self, corner_radii: impl Into<Corners<Pixels>>) -> Self {
3209 PaintQuad {
3210 corner_radii: corner_radii.into(),
3211 ..self
3212 }
3213 }
3214
3215 /// Set the border widths of the quad.
3216 pub fn border_widths(self, border_widths: impl Into<Edges<Pixels>>) -> Self {
3217 PaintQuad {
3218 border_widths: border_widths.into(),
3219 ..self
3220 }
3221 }
3222
3223 /// Set the border color of the quad.
3224 pub fn border_color(self, border_color: impl Into<Hsla>) -> Self {
3225 PaintQuad {
3226 border_color: border_color.into(),
3227 ..self
3228 }
3229 }
3230
3231 /// Set the background color of the quad.
3232 pub fn background(self, background: impl Into<Hsla>) -> Self {
3233 PaintQuad {
3234 background: background.into(),
3235 ..self
3236 }
3237 }
3238}
3239
3240/// Create a quad with the given parameters.
3241pub fn quad(
3242 bounds: Bounds<Pixels>,
3243 corner_radii: impl Into<Corners<Pixels>>,
3244 background: impl Into<Hsla>,
3245 border_widths: impl Into<Edges<Pixels>>,
3246 border_color: impl Into<Hsla>,
3247) -> PaintQuad {
3248 PaintQuad {
3249 bounds,
3250 corner_radii: corner_radii.into(),
3251 background: background.into(),
3252 border_widths: border_widths.into(),
3253 border_color: border_color.into(),
3254 }
3255}
3256
3257/// Create a filled quad with the given bounds and background color.
3258pub fn fill(bounds: impl Into<Bounds<Pixels>>, background: impl Into<Hsla>) -> PaintQuad {
3259 PaintQuad {
3260 bounds: bounds.into(),
3261 corner_radii: (0.).into(),
3262 background: background.into(),
3263 border_widths: (0.).into(),
3264 border_color: transparent_black(),
3265 }
3266}
3267
3268/// Create a rectangle outline with the given bounds, border color, and a 1px border width
3269pub fn outline(bounds: impl Into<Bounds<Pixels>>, border_color: impl Into<Hsla>) -> PaintQuad {
3270 PaintQuad {
3271 bounds: bounds.into(),
3272 corner_radii: (0.).into(),
3273 background: transparent_black(),
3274 border_widths: (1.).into(),
3275 border_color: border_color.into(),
3276 }
3277}