1use crate::{
2 hash, point, prelude::*, px, size, transparent_black, Action, AnyDrag, AnyElement, AnyTooltip,
3 AnyView, AppContext, Arena, Asset, AsyncWindowContext, AvailableSpace, Bounds, BoxShadow,
4 Context, Corners, CursorStyle, DevicePixels, DispatchActionListener, DispatchNodeId,
5 DispatchTree, DisplayId, Edges, Effect, Entity, EntityId, EventEmitter, FileDropEvent, Flatten,
6 FontId, Global, GlobalElementId, GlyphId, Hsla, ImageData, InputHandler, IsZero, KeyBinding,
7 KeyContext, KeyDownEvent, KeyEvent, KeyMatch, KeymatchResult, Keystroke, KeystrokeEvent,
8 LayoutId, LineLayoutIndex, Model, ModelContext, Modifiers, ModifiersChangedEvent,
9 MonochromeSprite, MouseButton, MouseEvent, MouseMoveEvent, MouseUpEvent, Path, Pixels,
10 PlatformAtlas, PlatformDisplay, PlatformInput, PlatformInputHandler, PlatformWindow, Point,
11 PolychromeSprite, PromptLevel, Quad, Render, RenderGlyphParams, RenderImageParams,
12 RenderSvgParams, ScaledPixels, Scene, Shadow, SharedString, Size, StrikethroughStyle, Style,
13 SubscriberSet, Subscription, TaffyLayoutEngine, Task, TextStyle, TextStyleRefinement,
14 TransformationMatrix, Underline, UnderlineStyle, View, VisualContext, WeakView,
15 WindowAppearance, WindowBackgroundAppearance, WindowBounds, WindowOptions, WindowParams,
16 WindowTextSystem, SUBPIXEL_VARIANTS,
17};
18use anyhow::{anyhow, Context as _, Result};
19use collections::{FxHashMap, FxHashSet};
20use derive_more::{Deref, DerefMut};
21use futures::channel::oneshot;
22use futures::{future::Shared, FutureExt};
23#[cfg(target_os = "macos")]
24use media::core_video::CVImageBuffer;
25use parking_lot::RwLock;
26use refineable::Refineable;
27use slotmap::SlotMap;
28use smallvec::SmallVec;
29use std::{
30 any::{Any, TypeId},
31 borrow::{Borrow, BorrowMut, Cow},
32 cell::{Cell, RefCell},
33 cmp,
34 fmt::{Debug, Display},
35 future::Future,
36 hash::{Hash, Hasher},
37 marker::PhantomData,
38 mem,
39 ops::Range,
40 rc::Rc,
41 sync::{
42 atomic::{AtomicUsize, Ordering::SeqCst},
43 Arc, Weak,
44 },
45 time::{Duration, Instant},
46};
47use util::post_inc;
48use util::{measure, ResultExt};
49
50mod prompts;
51
52pub use prompts::*;
53
54/// Represents the two different phases when dispatching events.
55#[derive(Default, Copy, Clone, Debug, Eq, PartialEq)]
56pub enum DispatchPhase {
57 /// After the capture phase comes the bubble phase, in which mouse event listeners are
58 /// invoked front to back and keyboard event listeners are invoked from the focused element
59 /// to the root of the element tree. This is the phase you'll most commonly want to use when
60 /// registering event listeners.
61 #[default]
62 Bubble,
63 /// During the initial capture phase, mouse event listeners are invoked back to front, and keyboard
64 /// listeners are invoked from the root of the tree downward toward the focused element. This phase
65 /// is used for special purposes such as clearing the "pressed" state for click events. If
66 /// you stop event propagation during this phase, you need to know what you're doing. Handlers
67 /// outside of the immediate region may rely on detecting non-local events during this phase.
68 Capture,
69}
70
71impl DispatchPhase {
72 /// Returns true if this represents the "bubble" phase.
73 pub fn bubble(self) -> bool {
74 self == DispatchPhase::Bubble
75 }
76
77 /// Returns true if this represents the "capture" phase.
78 pub fn capture(self) -> bool {
79 self == DispatchPhase::Capture
80 }
81}
82
83type AnyObserver = Box<dyn FnMut(&mut WindowContext) -> bool + 'static>;
84
85type AnyWindowFocusListener = Box<dyn FnMut(&FocusEvent, &mut WindowContext) -> bool + 'static>;
86
87struct FocusEvent {
88 previous_focus_path: SmallVec<[FocusId; 8]>,
89 current_focus_path: SmallVec<[FocusId; 8]>,
90}
91
92slotmap::new_key_type! {
93 /// A globally unique identifier for a focusable element.
94 pub struct FocusId;
95}
96
97thread_local! {
98 /// 8MB wasn't quite enough...
99 pub(crate) static ELEMENT_ARENA: RefCell<Arena> = RefCell::new(Arena::new(32 * 1024 * 1024));
100}
101
102impl FocusId {
103 /// Obtains whether the element associated with this handle is currently focused.
104 pub fn is_focused(&self, cx: &WindowContext) -> bool {
105 cx.window.focus == Some(*self)
106 }
107
108 /// Obtains whether the element associated with this handle contains the focused
109 /// element or is itself focused.
110 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
111 cx.focused()
112 .map_or(false, |focused| self.contains(focused.id, cx))
113 }
114
115 /// Obtains whether the element associated with this handle is contained within the
116 /// focused element or is itself focused.
117 pub fn within_focused(&self, cx: &WindowContext) -> bool {
118 let focused = cx.focused();
119 focused.map_or(false, |focused| focused.id.contains(*self, cx))
120 }
121
122 /// Obtains whether this handle contains the given handle in the most recently rendered frame.
123 pub(crate) fn contains(&self, other: Self, cx: &WindowContext) -> bool {
124 cx.window
125 .rendered_frame
126 .dispatch_tree
127 .focus_contains(*self, other)
128 }
129}
130
131/// A handle which can be used to track and manipulate the focused element in a window.
132pub struct FocusHandle {
133 pub(crate) id: FocusId,
134 handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
135}
136
137impl std::fmt::Debug for FocusHandle {
138 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
139 f.write_fmt(format_args!("FocusHandle({:?})", self.id))
140 }
141}
142
143impl FocusHandle {
144 pub(crate) fn new(handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>) -> Self {
145 let id = handles.write().insert(AtomicUsize::new(1));
146 Self {
147 id,
148 handles: handles.clone(),
149 }
150 }
151
152 pub(crate) fn for_id(
153 id: FocusId,
154 handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
155 ) -> Option<Self> {
156 let lock = handles.read();
157 let ref_count = lock.get(id)?;
158 if ref_count.load(SeqCst) == 0 {
159 None
160 } else {
161 ref_count.fetch_add(1, SeqCst);
162 Some(Self {
163 id,
164 handles: handles.clone(),
165 })
166 }
167 }
168
169 /// Converts this focus handle into a weak variant, which does not prevent it from being released.
170 pub fn downgrade(&self) -> WeakFocusHandle {
171 WeakFocusHandle {
172 id: self.id,
173 handles: Arc::downgrade(&self.handles),
174 }
175 }
176
177 /// Moves the focus to the element associated with this handle.
178 pub fn focus(&self, cx: &mut WindowContext) {
179 cx.focus(self)
180 }
181
182 /// Obtains whether the element associated with this handle is currently focused.
183 pub fn is_focused(&self, cx: &WindowContext) -> bool {
184 self.id.is_focused(cx)
185 }
186
187 /// Obtains whether the element associated with this handle contains the focused
188 /// element or is itself focused.
189 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
190 self.id.contains_focused(cx)
191 }
192
193 /// Obtains whether the element associated with this handle is contained within the
194 /// focused element or is itself focused.
195 pub fn within_focused(&self, cx: &WindowContext) -> bool {
196 self.id.within_focused(cx)
197 }
198
199 /// Obtains whether this handle contains the given handle in the most recently rendered frame.
200 pub fn contains(&self, other: &Self, cx: &WindowContext) -> bool {
201 self.id.contains(other.id, cx)
202 }
203
204 /// Dispatch an action on the element that rendered this focus handle
205 pub fn dispatch_action(&self, action: &dyn Action, cx: &mut WindowContext) {
206 if let Some(node_id) = cx
207 .window
208 .rendered_frame
209 .dispatch_tree
210 .focusable_node_id(self.id)
211 {
212 cx.dispatch_action_on_node(node_id, action)
213 }
214 }
215}
216
217impl Clone for FocusHandle {
218 fn clone(&self) -> Self {
219 Self::for_id(self.id, &self.handles).unwrap()
220 }
221}
222
223impl PartialEq for FocusHandle {
224 fn eq(&self, other: &Self) -> bool {
225 self.id == other.id
226 }
227}
228
229impl Eq for FocusHandle {}
230
231impl Drop for FocusHandle {
232 fn drop(&mut self) {
233 self.handles
234 .read()
235 .get(self.id)
236 .unwrap()
237 .fetch_sub(1, SeqCst);
238 }
239}
240
241/// A weak reference to a focus handle.
242#[derive(Clone, Debug)]
243pub struct WeakFocusHandle {
244 pub(crate) id: FocusId,
245 handles: Weak<RwLock<SlotMap<FocusId, AtomicUsize>>>,
246}
247
248impl WeakFocusHandle {
249 /// Attempts to upgrade the [WeakFocusHandle] to a [FocusHandle].
250 pub fn upgrade(&self) -> Option<FocusHandle> {
251 let handles = self.handles.upgrade()?;
252 FocusHandle::for_id(self.id, &handles)
253 }
254}
255
256impl PartialEq for WeakFocusHandle {
257 fn eq(&self, other: &WeakFocusHandle) -> bool {
258 self.id == other.id
259 }
260}
261
262impl Eq for WeakFocusHandle {}
263
264impl PartialEq<FocusHandle> for WeakFocusHandle {
265 fn eq(&self, other: &FocusHandle) -> bool {
266 self.id == other.id
267 }
268}
269
270impl PartialEq<WeakFocusHandle> for FocusHandle {
271 fn eq(&self, other: &WeakFocusHandle) -> bool {
272 self.id == other.id
273 }
274}
275
276/// FocusableView allows users of your view to easily
277/// focus it (using cx.focus_view(view))
278pub trait FocusableView: 'static + Render {
279 /// Returns the focus handle associated with this view.
280 fn focus_handle(&self, cx: &AppContext) -> FocusHandle;
281}
282
283/// ManagedView is a view (like a Modal, Popover, Menu, etc.)
284/// where the lifecycle of the view is handled by another view.
285pub trait ManagedView: FocusableView + EventEmitter<DismissEvent> {}
286
287impl<M: FocusableView + EventEmitter<DismissEvent>> ManagedView for M {}
288
289/// Emitted by implementers of [`ManagedView`] to indicate the view should be dismissed, such as when a view is presented as a modal.
290pub struct DismissEvent;
291
292type FrameCallback = Box<dyn FnOnce(&mut WindowContext)>;
293
294pub(crate) type AnyMouseListener =
295 Box<dyn FnMut(&dyn Any, DispatchPhase, &mut WindowContext) + 'static>;
296
297#[derive(Clone)]
298pub(crate) struct CursorStyleRequest {
299 pub(crate) hitbox_id: HitboxId,
300 pub(crate) style: CursorStyle,
301}
302
303/// An identifier for a [Hitbox].
304#[derive(Copy, Clone, Debug, Default, Eq, PartialEq)]
305pub struct HitboxId(usize);
306
307impl HitboxId {
308 /// Checks if the hitbox with this id is currently hovered.
309 pub fn is_hovered(&self, cx: &WindowContext) -> bool {
310 cx.window.mouse_hit_test.0.contains(self)
311 }
312}
313
314/// A rectangular region that potentially blocks hitboxes inserted prior.
315/// See [WindowContext::insert_hitbox] for more details.
316#[derive(Clone, Debug, Deref)]
317pub struct Hitbox {
318 /// A unique identifier for the hitbox.
319 pub id: HitboxId,
320 /// The bounds of the hitbox.
321 #[deref]
322 pub bounds: Bounds<Pixels>,
323 /// The content mask when the hitbox was inserted.
324 pub content_mask: ContentMask<Pixels>,
325 /// Whether the hitbox occludes other hitboxes inserted prior.
326 pub opaque: bool,
327}
328
329impl Hitbox {
330 /// Checks if the hitbox is currently hovered.
331 pub fn is_hovered(&self, cx: &WindowContext) -> bool {
332 self.id.is_hovered(cx)
333 }
334}
335
336#[derive(Default, Eq, PartialEq)]
337pub(crate) struct HitTest(SmallVec<[HitboxId; 8]>);
338
339/// An identifier for a tooltip.
340#[derive(Copy, Clone, Debug, Default, Eq, PartialEq)]
341pub struct TooltipId(usize);
342
343impl TooltipId {
344 /// Checks if the tooltip is currently hovered.
345 pub fn is_hovered(&self, cx: &WindowContext) -> bool {
346 cx.window
347 .tooltip_bounds
348 .as_ref()
349 .map_or(false, |tooltip_bounds| {
350 tooltip_bounds.id == *self && tooltip_bounds.bounds.contains(&cx.mouse_position())
351 })
352 }
353}
354
355pub(crate) struct TooltipBounds {
356 id: TooltipId,
357 bounds: Bounds<Pixels>,
358}
359
360#[derive(Clone)]
361pub(crate) struct TooltipRequest {
362 id: TooltipId,
363 tooltip: AnyTooltip,
364}
365
366pub(crate) struct DeferredDraw {
367 priority: usize,
368 parent_node: DispatchNodeId,
369 element_id_stack: SmallVec<[ElementId; 32]>,
370 text_style_stack: Vec<TextStyleRefinement>,
371 element: Option<AnyElement>,
372 absolute_offset: Point<Pixels>,
373 prepaint_range: Range<PrepaintStateIndex>,
374 paint_range: Range<PaintIndex>,
375}
376
377pub(crate) struct Frame {
378 pub(crate) focus: Option<FocusId>,
379 pub(crate) window_active: bool,
380 pub(crate) element_states: FxHashMap<(GlobalElementId, TypeId), ElementStateBox>,
381 accessed_element_states: Vec<(GlobalElementId, TypeId)>,
382 pub(crate) mouse_listeners: Vec<Option<AnyMouseListener>>,
383 pub(crate) dispatch_tree: DispatchTree,
384 pub(crate) scene: Scene,
385 pub(crate) hitboxes: Vec<Hitbox>,
386 pub(crate) deferred_draws: Vec<DeferredDraw>,
387 pub(crate) input_handlers: Vec<Option<PlatformInputHandler>>,
388 pub(crate) tooltip_requests: Vec<Option<TooltipRequest>>,
389 pub(crate) cursor_styles: Vec<CursorStyleRequest>,
390 #[cfg(any(test, feature = "test-support"))]
391 pub(crate) debug_bounds: FxHashMap<String, Bounds<Pixels>>,
392}
393
394#[derive(Clone, Default)]
395pub(crate) struct PrepaintStateIndex {
396 hitboxes_index: usize,
397 tooltips_index: usize,
398 deferred_draws_index: usize,
399 dispatch_tree_index: usize,
400 accessed_element_states_index: usize,
401 line_layout_index: LineLayoutIndex,
402}
403
404#[derive(Clone, Default)]
405pub(crate) struct PaintIndex {
406 scene_index: usize,
407 mouse_listeners_index: usize,
408 input_handlers_index: usize,
409 cursor_styles_index: usize,
410 accessed_element_states_index: usize,
411 line_layout_index: LineLayoutIndex,
412}
413
414impl Frame {
415 pub(crate) fn new(dispatch_tree: DispatchTree) -> Self {
416 Frame {
417 focus: None,
418 window_active: false,
419 element_states: FxHashMap::default(),
420 accessed_element_states: Vec::new(),
421 mouse_listeners: Vec::new(),
422 dispatch_tree,
423 scene: Scene::default(),
424 hitboxes: Vec::new(),
425 deferred_draws: Vec::new(),
426 input_handlers: Vec::new(),
427 tooltip_requests: Vec::new(),
428 cursor_styles: Vec::new(),
429
430 #[cfg(any(test, feature = "test-support"))]
431 debug_bounds: FxHashMap::default(),
432 }
433 }
434
435 pub(crate) fn clear(&mut self) {
436 self.element_states.clear();
437 self.accessed_element_states.clear();
438 self.mouse_listeners.clear();
439 self.dispatch_tree.clear();
440 self.scene.clear();
441 self.input_handlers.clear();
442 self.tooltip_requests.clear();
443 self.cursor_styles.clear();
444 self.hitboxes.clear();
445 self.deferred_draws.clear();
446 }
447
448 pub(crate) fn hit_test(&self, position: Point<Pixels>) -> HitTest {
449 let mut hit_test = HitTest::default();
450 for hitbox in self.hitboxes.iter().rev() {
451 let bounds = hitbox.bounds.intersect(&hitbox.content_mask.bounds);
452 if bounds.contains(&position) {
453 hit_test.0.push(hitbox.id);
454 if hitbox.opaque {
455 break;
456 }
457 }
458 }
459 hit_test
460 }
461
462 pub(crate) fn focus_path(&self) -> SmallVec<[FocusId; 8]> {
463 self.focus
464 .map(|focus_id| self.dispatch_tree.focus_path(focus_id))
465 .unwrap_or_default()
466 }
467
468 pub(crate) fn finish(&mut self, prev_frame: &mut Self) {
469 for element_state_key in &self.accessed_element_states {
470 if let Some((element_state_key, element_state)) =
471 prev_frame.element_states.remove_entry(element_state_key)
472 {
473 self.element_states.insert(element_state_key, element_state);
474 }
475 }
476
477 self.scene.finish();
478 }
479}
480
481// Holds the state for a specific window.
482#[doc(hidden)]
483pub struct Window {
484 pub(crate) handle: AnyWindowHandle,
485 pub(crate) removed: bool,
486 pub(crate) platform_window: Box<dyn PlatformWindow>,
487 display_id: DisplayId,
488 sprite_atlas: Arc<dyn PlatformAtlas>,
489 text_system: Arc<WindowTextSystem>,
490 pub(crate) rem_size: Pixels,
491 pub(crate) viewport_size: Size<Pixels>,
492 layout_engine: Option<TaffyLayoutEngine>,
493 pub(crate) root_view: Option<AnyView>,
494 pub(crate) element_id_stack: SmallVec<[ElementId; 32]>,
495 pub(crate) text_style_stack: Vec<TextStyleRefinement>,
496 pub(crate) element_offset_stack: Vec<Point<Pixels>>,
497 pub(crate) content_mask_stack: Vec<ContentMask<Pixels>>,
498 pub(crate) requested_autoscroll: Option<Bounds<Pixels>>,
499 pub(crate) rendered_frame: Frame,
500 pub(crate) next_frame: Frame,
501 pub(crate) next_hitbox_id: HitboxId,
502 pub(crate) next_tooltip_id: TooltipId,
503 pub(crate) tooltip_bounds: Option<TooltipBounds>,
504 next_frame_callbacks: Rc<RefCell<Vec<FrameCallback>>>,
505 pub(crate) dirty_views: FxHashSet<EntityId>,
506 pub(crate) focus_handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
507 focus_listeners: SubscriberSet<(), AnyWindowFocusListener>,
508 focus_lost_listeners: SubscriberSet<(), AnyObserver>,
509 default_prevented: bool,
510 mouse_position: Point<Pixels>,
511 mouse_hit_test: HitTest,
512 modifiers: Modifiers,
513 scale_factor: f32,
514 bounds_observers: SubscriberSet<(), AnyObserver>,
515 appearance: WindowAppearance,
516 appearance_observers: SubscriberSet<(), AnyObserver>,
517 active: Rc<Cell<bool>>,
518 pub(crate) dirty: Rc<Cell<bool>>,
519 pub(crate) needs_present: Rc<Cell<bool>>,
520 pub(crate) last_input_timestamp: Rc<Cell<Instant>>,
521 pub(crate) refreshing: bool,
522 pub(crate) draw_phase: DrawPhase,
523 activation_observers: SubscriberSet<(), AnyObserver>,
524 pub(crate) focus: Option<FocusId>,
525 focus_enabled: bool,
526 pending_input: Option<PendingInput>,
527 prompt: Option<RenderablePromptHandle>,
528}
529
530#[derive(Clone, Copy, Debug, Eq, PartialEq)]
531pub(crate) enum DrawPhase {
532 None,
533 Prepaint,
534 Paint,
535 Focus,
536}
537
538#[derive(Default, Debug)]
539struct PendingInput {
540 keystrokes: SmallVec<[Keystroke; 1]>,
541 bindings: SmallVec<[KeyBinding; 1]>,
542 focus: Option<FocusId>,
543 timer: Option<Task<()>>,
544}
545
546impl PendingInput {
547 fn input(&self) -> String {
548 self.keystrokes
549 .iter()
550 .flat_map(|k| k.ime_key.clone())
551 .collect::<Vec<String>>()
552 .join("")
553 }
554
555 fn used_by_binding(&self, binding: &KeyBinding) -> bool {
556 if self.keystrokes.is_empty() {
557 return true;
558 }
559 let keystroke = &self.keystrokes[0];
560 for candidate in keystroke.match_candidates() {
561 if binding.match_keystrokes(&[candidate]) == KeyMatch::Pending {
562 return true;
563 }
564 }
565 false
566 }
567}
568
569pub(crate) struct ElementStateBox {
570 pub(crate) inner: Box<dyn Any>,
571 #[cfg(debug_assertions)]
572 pub(crate) type_name: &'static str,
573}
574
575fn default_bounds(display_id: Option<DisplayId>, cx: &mut AppContext) -> Bounds<DevicePixels> {
576 const DEFAULT_WINDOW_SIZE: Size<DevicePixels> = size(DevicePixels(1024), DevicePixels(700));
577 const DEFAULT_WINDOW_OFFSET: Point<DevicePixels> = point(DevicePixels(0), DevicePixels(35));
578
579 cx.active_window()
580 .and_then(|w| w.update(cx, |_, cx| cx.bounds()).ok())
581 .map(|bounds| bounds.map_origin(|origin| origin + DEFAULT_WINDOW_OFFSET))
582 .unwrap_or_else(|| {
583 let display = display_id
584 .map(|id| cx.find_display(id))
585 .unwrap_or_else(|| cx.primary_display());
586
587 display
588 .map(|display| {
589 let center = display.bounds().center();
590 let offset = DEFAULT_WINDOW_SIZE / 2;
591 let origin = point(center.x - offset.width, center.y - offset.height);
592 Bounds::new(origin, DEFAULT_WINDOW_SIZE)
593 })
594 .unwrap_or_else(|| {
595 Bounds::new(point(DevicePixels(0), DevicePixels(0)), DEFAULT_WINDOW_SIZE)
596 })
597 })
598}
599
600impl Window {
601 pub(crate) fn new(
602 handle: AnyWindowHandle,
603 options: WindowOptions,
604 cx: &mut AppContext,
605 ) -> Self {
606 let WindowOptions {
607 window_bounds,
608 titlebar,
609 focus,
610 show,
611 kind,
612 is_movable,
613 display_id,
614 window_background,
615 app_id,
616 } = options;
617
618 let bounds = window_bounds
619 .map(|bounds| bounds.get_bounds())
620 .unwrap_or_else(|| default_bounds(display_id, cx));
621 let mut platform_window = cx.platform.open_window(
622 handle,
623 WindowParams {
624 bounds,
625 titlebar,
626 kind,
627 is_movable,
628 focus,
629 show,
630 display_id,
631 window_background,
632 },
633 );
634 let display_id = platform_window.display().id();
635 let sprite_atlas = platform_window.sprite_atlas();
636 let mouse_position = platform_window.mouse_position();
637 let modifiers = platform_window.modifiers();
638 let content_size = platform_window.content_size();
639 let scale_factor = platform_window.scale_factor();
640 let appearance = platform_window.appearance();
641 let text_system = Arc::new(WindowTextSystem::new(cx.text_system().clone()));
642 let dirty = Rc::new(Cell::new(true));
643 let active = Rc::new(Cell::new(platform_window.is_active()));
644 let needs_present = Rc::new(Cell::new(false));
645 let next_frame_callbacks: Rc<RefCell<Vec<FrameCallback>>> = Default::default();
646 let last_input_timestamp = Rc::new(Cell::new(Instant::now()));
647
648 if let Some(ref window_open_state) = window_bounds {
649 match window_open_state {
650 WindowBounds::Fullscreen(_) => platform_window.toggle_fullscreen(),
651 WindowBounds::Maximized(_) => platform_window.zoom(),
652 WindowBounds::Windowed(_) => {}
653 }
654 }
655
656 platform_window.on_close(Box::new({
657 let mut cx = cx.to_async();
658 move || {
659 let _ = handle.update(&mut cx, |_, cx| cx.remove_window());
660 }
661 }));
662 platform_window.on_request_frame(Box::new({
663 let mut cx = cx.to_async();
664 let dirty = dirty.clone();
665 let active = active.clone();
666 let needs_present = needs_present.clone();
667 let next_frame_callbacks = next_frame_callbacks.clone();
668 let last_input_timestamp = last_input_timestamp.clone();
669 move || {
670 let next_frame_callbacks = next_frame_callbacks.take();
671 if !next_frame_callbacks.is_empty() {
672 handle
673 .update(&mut cx, |_, cx| {
674 for callback in next_frame_callbacks {
675 callback(cx);
676 }
677 })
678 .log_err();
679 }
680
681 // Keep presenting the current scene for 1 extra second since the
682 // last input to prevent the display from underclocking the refresh rate.
683 let needs_present = needs_present.get()
684 || (active.get()
685 && last_input_timestamp.get().elapsed() < Duration::from_secs(1));
686
687 if dirty.get() {
688 measure("frame duration", || {
689 handle
690 .update(&mut cx, |_, cx| {
691 cx.draw();
692 cx.present();
693 })
694 .log_err();
695 })
696 } else if needs_present {
697 handle.update(&mut cx, |_, cx| cx.present()).log_err();
698 }
699
700 handle
701 .update(&mut cx, |_, cx| {
702 cx.complete_frame();
703 })
704 .log_err();
705 }
706 }));
707 platform_window.on_resize(Box::new({
708 let mut cx = cx.to_async();
709 move |_, _| {
710 handle
711 .update(&mut cx, |_, cx| cx.bounds_changed())
712 .log_err();
713 }
714 }));
715 platform_window.on_moved(Box::new({
716 let mut cx = cx.to_async();
717 move || {
718 handle
719 .update(&mut cx, |_, cx| cx.bounds_changed())
720 .log_err();
721 }
722 }));
723 platform_window.on_appearance_changed(Box::new({
724 let mut cx = cx.to_async();
725 move || {
726 handle
727 .update(&mut cx, |_, cx| cx.appearance_changed())
728 .log_err();
729 }
730 }));
731 platform_window.on_active_status_change(Box::new({
732 let mut cx = cx.to_async();
733 move |active| {
734 handle
735 .update(&mut cx, |_, cx| {
736 cx.window.active.set(active);
737 cx.window
738 .activation_observers
739 .clone()
740 .retain(&(), |callback| callback(cx));
741 cx.refresh();
742 })
743 .log_err();
744 }
745 }));
746
747 platform_window.on_input({
748 let mut cx = cx.to_async();
749 Box::new(move |event| {
750 handle
751 .update(&mut cx, |_, cx| cx.dispatch_event(event))
752 .log_err()
753 .unwrap_or(DispatchEventResult::default())
754 })
755 });
756
757 if let Some(app_id) = app_id {
758 platform_window.set_app_id(&app_id);
759 }
760
761 Window {
762 handle,
763 removed: false,
764 platform_window,
765 display_id,
766 sprite_atlas,
767 text_system,
768 rem_size: px(16.),
769 viewport_size: content_size,
770 layout_engine: Some(TaffyLayoutEngine::new()),
771 root_view: None,
772 element_id_stack: SmallVec::default(),
773 text_style_stack: Vec::new(),
774 element_offset_stack: Vec::new(),
775 content_mask_stack: Vec::new(),
776 requested_autoscroll: None,
777 rendered_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
778 next_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
779 next_frame_callbacks,
780 next_hitbox_id: HitboxId::default(),
781 next_tooltip_id: TooltipId::default(),
782 tooltip_bounds: None,
783 dirty_views: FxHashSet::default(),
784 focus_handles: Arc::new(RwLock::new(SlotMap::with_key())),
785 focus_listeners: SubscriberSet::new(),
786 focus_lost_listeners: SubscriberSet::new(),
787 default_prevented: true,
788 mouse_position,
789 mouse_hit_test: HitTest::default(),
790 modifiers,
791 scale_factor,
792 bounds_observers: SubscriberSet::new(),
793 appearance,
794 appearance_observers: SubscriberSet::new(),
795 active,
796 dirty,
797 needs_present,
798 last_input_timestamp,
799 refreshing: false,
800 draw_phase: DrawPhase::None,
801 activation_observers: SubscriberSet::new(),
802 focus: None,
803 focus_enabled: true,
804 pending_input: None,
805 prompt: None,
806 }
807 }
808 fn new_focus_listener(
809 &mut self,
810 value: AnyWindowFocusListener,
811 ) -> (Subscription, impl FnOnce()) {
812 self.focus_listeners.insert((), value)
813 }
814}
815
816#[derive(Clone, Debug, Default, PartialEq, Eq)]
817pub(crate) struct DispatchEventResult {
818 pub propagate: bool,
819 pub default_prevented: bool,
820}
821
822/// Indicates which region of the window is visible. Content falling outside of this mask will not be
823/// rendered. Currently, only rectangular content masks are supported, but we give the mask its own type
824/// to leave room to support more complex shapes in the future.
825#[derive(Clone, Debug, Default, PartialEq, Eq)]
826#[repr(C)]
827pub struct ContentMask<P: Clone + Default + Debug> {
828 /// The bounds
829 pub bounds: Bounds<P>,
830}
831
832impl ContentMask<Pixels> {
833 /// Scale the content mask's pixel units by the given scaling factor.
834 pub fn scale(&self, factor: f32) -> ContentMask<ScaledPixels> {
835 ContentMask {
836 bounds: self.bounds.scale(factor),
837 }
838 }
839
840 /// Intersect the content mask with the given content mask.
841 pub fn intersect(&self, other: &Self) -> Self {
842 let bounds = self.bounds.intersect(&other.bounds);
843 ContentMask { bounds }
844 }
845}
846
847/// Provides access to application state in the context of a single window. Derefs
848/// to an [`AppContext`], so you can also pass a [`WindowContext`] to any method that takes
849/// an [`AppContext`] and call any [`AppContext`] methods.
850pub struct WindowContext<'a> {
851 pub(crate) app: &'a mut AppContext,
852 pub(crate) window: &'a mut Window,
853}
854
855impl<'a> WindowContext<'a> {
856 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window) -> Self {
857 Self { app, window }
858 }
859
860 /// Obtain a handle to the window that belongs to this context.
861 pub fn window_handle(&self) -> AnyWindowHandle {
862 self.window.handle
863 }
864
865 /// Mark the window as dirty, scheduling it to be redrawn on the next frame.
866 pub fn refresh(&mut self) {
867 if self.window.draw_phase == DrawPhase::None {
868 self.window.refreshing = true;
869 self.window.dirty.set(true);
870 }
871 }
872
873 /// Indicate that this view has changed, which will invoke any observers and also mark the window as dirty.
874 /// If this view or any of its ancestors are *cached*, notifying it will cause it or its ancestors to be redrawn.
875 pub fn notify(&mut self, view_id: EntityId) {
876 for view_id in self
877 .window
878 .rendered_frame
879 .dispatch_tree
880 .view_path(view_id)
881 .into_iter()
882 .rev()
883 {
884 if !self.window.dirty_views.insert(view_id) {
885 break;
886 }
887 }
888
889 if self.window.draw_phase == DrawPhase::None {
890 self.window.dirty.set(true);
891 self.app.push_effect(Effect::Notify { emitter: view_id });
892 }
893 }
894
895 /// Close this window.
896 pub fn remove_window(&mut self) {
897 self.window.removed = true;
898 }
899
900 /// Obtain a new [`FocusHandle`], which allows you to track and manipulate the keyboard focus
901 /// for elements rendered within this window.
902 pub fn focus_handle(&mut self) -> FocusHandle {
903 FocusHandle::new(&self.window.focus_handles)
904 }
905
906 /// Obtain the currently focused [`FocusHandle`]. If no elements are focused, returns `None`.
907 pub fn focused(&self) -> Option<FocusHandle> {
908 self.window
909 .focus
910 .and_then(|id| FocusHandle::for_id(id, &self.window.focus_handles))
911 }
912
913 /// Move focus to the element associated with the given [`FocusHandle`].
914 pub fn focus(&mut self, handle: &FocusHandle) {
915 if !self.window.focus_enabled || self.window.focus == Some(handle.id) {
916 return;
917 }
918
919 self.window.focus = Some(handle.id);
920 self.window
921 .rendered_frame
922 .dispatch_tree
923 .clear_pending_keystrokes();
924 self.refresh();
925 }
926
927 /// Remove focus from all elements within this context's window.
928 pub fn blur(&mut self) {
929 if !self.window.focus_enabled {
930 return;
931 }
932
933 self.window.focus = None;
934 self.refresh();
935 }
936
937 /// Blur the window and don't allow anything in it to be focused again.
938 pub fn disable_focus(&mut self) {
939 self.blur();
940 self.window.focus_enabled = false;
941 }
942
943 /// Accessor for the text system.
944 pub fn text_system(&self) -> &Arc<WindowTextSystem> {
945 &self.window.text_system
946 }
947
948 /// The current text style. Which is composed of all the style refinements provided to `with_text_style`.
949 pub fn text_style(&self) -> TextStyle {
950 let mut style = TextStyle::default();
951 for refinement in &self.window.text_style_stack {
952 style.refine(refinement);
953 }
954 style
955 }
956
957 /// Check if the platform window is maximized
958 /// On some platforms (namely Windows) this is different than the bounds being the size of the display
959 pub fn is_maximized(&self) -> bool {
960 self.window.platform_window.is_maximized()
961 }
962
963 /// Return the `WindowBounds` to indicate that how a window should be opened
964 /// after it has been closed
965 pub fn window_bounds(&self) -> WindowBounds {
966 self.window.platform_window.window_bounds()
967 }
968
969 /// Dispatch the given action on the currently focused element.
970 pub fn dispatch_action(&mut self, action: Box<dyn Action>) {
971 let focus_handle = self.focused();
972
973 let window = self.window.handle;
974 self.app.defer(move |cx| {
975 window
976 .update(cx, |_, cx| {
977 let node_id = focus_handle
978 .and_then(|handle| {
979 cx.window
980 .rendered_frame
981 .dispatch_tree
982 .focusable_node_id(handle.id)
983 })
984 .unwrap_or_else(|| cx.window.rendered_frame.dispatch_tree.root_node_id());
985
986 cx.dispatch_action_on_node(node_id, action.as_ref());
987 })
988 .log_err();
989 })
990 }
991
992 pub(crate) fn dispatch_keystroke_observers(
993 &mut self,
994 event: &dyn Any,
995 action: Option<Box<dyn Action>>,
996 ) {
997 let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() else {
998 return;
999 };
1000
1001 self.keystroke_observers
1002 .clone()
1003 .retain(&(), move |callback| {
1004 (callback)(
1005 &KeystrokeEvent {
1006 keystroke: key_down_event.keystroke.clone(),
1007 action: action.as_ref().map(|action| action.boxed_clone()),
1008 },
1009 self,
1010 );
1011 true
1012 });
1013 }
1014
1015 pub(crate) fn clear_pending_keystrokes(&mut self) {
1016 self.window
1017 .rendered_frame
1018 .dispatch_tree
1019 .clear_pending_keystrokes();
1020 self.window
1021 .next_frame
1022 .dispatch_tree
1023 .clear_pending_keystrokes();
1024 }
1025
1026 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
1027 /// that are currently on the stack to be returned to the app.
1028 pub fn defer(&mut self, f: impl FnOnce(&mut WindowContext) + 'static) {
1029 let handle = self.window.handle;
1030 self.app.defer(move |cx| {
1031 handle.update(cx, |_, cx| f(cx)).ok();
1032 });
1033 }
1034
1035 /// Subscribe to events emitted by a model or view.
1036 /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
1037 /// The callback will be invoked a handle to the emitting entity (either a [`View`] or [`Model`]), the event, and a window context for the current window.
1038 pub fn subscribe<Emitter, E, Evt>(
1039 &mut self,
1040 entity: &E,
1041 mut on_event: impl FnMut(E, &Evt, &mut WindowContext<'_>) + 'static,
1042 ) -> Subscription
1043 where
1044 Emitter: EventEmitter<Evt>,
1045 E: Entity<Emitter>,
1046 Evt: 'static,
1047 {
1048 let entity_id = entity.entity_id();
1049 let entity = entity.downgrade();
1050 let window_handle = self.window.handle;
1051 self.app.new_subscription(
1052 entity_id,
1053 (
1054 TypeId::of::<Evt>(),
1055 Box::new(move |event, cx| {
1056 window_handle
1057 .update(cx, |_, cx| {
1058 if let Some(handle) = E::upgrade_from(&entity) {
1059 let event = event.downcast_ref().expect("invalid event type");
1060 on_event(handle, event, cx);
1061 true
1062 } else {
1063 false
1064 }
1065 })
1066 .unwrap_or(false)
1067 }),
1068 ),
1069 )
1070 }
1071
1072 /// Creates an [`AsyncWindowContext`], which has a static lifetime and can be held across
1073 /// await points in async code.
1074 pub fn to_async(&self) -> AsyncWindowContext {
1075 AsyncWindowContext::new(self.app.to_async(), self.window.handle)
1076 }
1077
1078 /// Schedule the given closure to be run directly after the current frame is rendered.
1079 pub fn on_next_frame(&mut self, callback: impl FnOnce(&mut WindowContext) + 'static) {
1080 RefCell::borrow_mut(&self.window.next_frame_callbacks).push(Box::new(callback));
1081 }
1082
1083 /// Spawn the future returned by the given closure on the application thread pool.
1084 /// The closure is provided a handle to the current window and an `AsyncWindowContext` for
1085 /// use within your future.
1086 pub fn spawn<Fut, R>(&mut self, f: impl FnOnce(AsyncWindowContext) -> Fut) -> Task<R>
1087 where
1088 R: 'static,
1089 Fut: Future<Output = R> + 'static,
1090 {
1091 self.app
1092 .spawn(|app| f(AsyncWindowContext::new(app, self.window.handle)))
1093 }
1094
1095 fn bounds_changed(&mut self) {
1096 self.window.scale_factor = self.window.platform_window.scale_factor();
1097 self.window.viewport_size = self.window.platform_window.content_size();
1098 self.window.display_id = self.window.platform_window.display().id();
1099 self.refresh();
1100
1101 self.window
1102 .bounds_observers
1103 .clone()
1104 .retain(&(), |callback| callback(self));
1105 }
1106
1107 /// Returns the bounds of the current window in the global coordinate space, which could span across multiple displays.
1108 pub fn bounds(&self) -> Bounds<DevicePixels> {
1109 self.window.platform_window.bounds()
1110 }
1111
1112 /// Returns whether or not the window is currently fullscreen
1113 pub fn is_fullscreen(&self) -> bool {
1114 self.window.platform_window.is_fullscreen()
1115 }
1116
1117 fn appearance_changed(&mut self) {
1118 self.window.appearance = self.window.platform_window.appearance();
1119
1120 self.window
1121 .appearance_observers
1122 .clone()
1123 .retain(&(), |callback| callback(self));
1124 }
1125
1126 /// Returns the appearance of the current window.
1127 pub fn appearance(&self) -> WindowAppearance {
1128 self.window.appearance
1129 }
1130
1131 /// Returns the size of the drawable area within the window.
1132 pub fn viewport_size(&self) -> Size<Pixels> {
1133 self.window.viewport_size
1134 }
1135
1136 /// Returns whether this window is focused by the operating system (receiving key events).
1137 pub fn is_window_active(&self) -> bool {
1138 self.window.active.get()
1139 }
1140
1141 /// Toggle zoom on the window.
1142 pub fn zoom_window(&self) {
1143 self.window.platform_window.zoom();
1144 }
1145
1146 /// Opens the native title bar context menu, useful when implementing client side decorations (Wayland only)
1147 pub fn show_window_menu(&self, position: Point<Pixels>) {
1148 self.window.platform_window.show_window_menu(position)
1149 }
1150
1151 /// Tells the compositor to take control of window movement (Wayland only)
1152 ///
1153 /// Events may not be received during a move operation.
1154 pub fn start_system_move(&self) {
1155 self.window.platform_window.start_system_move()
1156 }
1157
1158 /// Returns whether the title bar window controls need to be rendered by the application (Wayland and X11)
1159 pub fn should_render_window_controls(&self) -> bool {
1160 self.window.platform_window.should_render_window_controls()
1161 }
1162
1163 /// Updates the window's title at the platform level.
1164 pub fn set_window_title(&mut self, title: &str) {
1165 self.window.platform_window.set_title(title);
1166 }
1167
1168 /// Sets the application identifier.
1169 pub fn set_app_id(&mut self, app_id: &str) {
1170 self.window.platform_window.set_app_id(app_id);
1171 }
1172
1173 /// Sets the window background appearance.
1174 pub fn set_background_appearance(&mut self, background_appearance: WindowBackgroundAppearance) {
1175 self.window
1176 .platform_window
1177 .set_background_appearance(background_appearance);
1178 }
1179
1180 /// Mark the window as dirty at the platform level.
1181 pub fn set_window_edited(&mut self, edited: bool) {
1182 self.window.platform_window.set_edited(edited);
1183 }
1184
1185 /// Determine the display on which the window is visible.
1186 pub fn display(&self) -> Option<Rc<dyn PlatformDisplay>> {
1187 self.platform
1188 .displays()
1189 .into_iter()
1190 .find(|display| display.id() == self.window.display_id)
1191 }
1192
1193 /// Show the platform character palette.
1194 pub fn show_character_palette(&self) {
1195 self.window.platform_window.show_character_palette();
1196 }
1197
1198 /// The scale factor of the display associated with the window. For example, it could
1199 /// return 2.0 for a "retina" display, indicating that each logical pixel should actually
1200 /// be rendered as two pixels on screen.
1201 pub fn scale_factor(&self) -> f32 {
1202 self.window.scale_factor
1203 }
1204
1205 /// The size of an em for the base font of the application. Adjusting this value allows the
1206 /// UI to scale, just like zooming a web page.
1207 pub fn rem_size(&self) -> Pixels {
1208 self.window.rem_size
1209 }
1210
1211 /// Sets the size of an em for the base font of the application. Adjusting this value allows the
1212 /// UI to scale, just like zooming a web page.
1213 pub fn set_rem_size(&mut self, rem_size: impl Into<Pixels>) {
1214 self.window.rem_size = rem_size.into();
1215 }
1216
1217 /// The line height associated with the current text style.
1218 pub fn line_height(&self) -> Pixels {
1219 let rem_size = self.rem_size();
1220 let text_style = self.text_style();
1221 text_style
1222 .line_height
1223 .to_pixels(text_style.font_size, rem_size)
1224 }
1225
1226 /// Call to prevent the default action of an event. Currently only used to prevent
1227 /// parent elements from becoming focused on mouse down.
1228 pub fn prevent_default(&mut self) {
1229 self.window.default_prevented = true;
1230 }
1231
1232 /// Obtain whether default has been prevented for the event currently being dispatched.
1233 pub fn default_prevented(&self) -> bool {
1234 self.window.default_prevented
1235 }
1236
1237 /// Determine whether the given action is available along the dispatch path to the currently focused element.
1238 pub fn is_action_available(&self, action: &dyn Action) -> bool {
1239 let target = self
1240 .focused()
1241 .and_then(|focused_handle| {
1242 self.window
1243 .rendered_frame
1244 .dispatch_tree
1245 .focusable_node_id(focused_handle.id)
1246 })
1247 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
1248 self.window
1249 .rendered_frame
1250 .dispatch_tree
1251 .is_action_available(action, target)
1252 }
1253
1254 /// The position of the mouse relative to the window.
1255 pub fn mouse_position(&self) -> Point<Pixels> {
1256 self.window.mouse_position
1257 }
1258
1259 /// The current state of the keyboard's modifiers
1260 pub fn modifiers(&self) -> Modifiers {
1261 self.window.modifiers
1262 }
1263
1264 fn complete_frame(&self) {
1265 self.window.platform_window.completed_frame();
1266 }
1267
1268 /// Produces a new frame and assigns it to `rendered_frame`. To actually show
1269 /// the contents of the new [Scene], use [present].
1270 #[profiling::function]
1271 pub fn draw(&mut self) {
1272 self.window.dirty.set(false);
1273 self.window.requested_autoscroll = None;
1274
1275 // Restore the previously-used input handler.
1276 if let Some(input_handler) = self.window.platform_window.take_input_handler() {
1277 self.window
1278 .rendered_frame
1279 .input_handlers
1280 .push(Some(input_handler));
1281 }
1282
1283 self.draw_roots();
1284 self.window.dirty_views.clear();
1285
1286 self.window
1287 .next_frame
1288 .dispatch_tree
1289 .preserve_pending_keystrokes(
1290 &mut self.window.rendered_frame.dispatch_tree,
1291 self.window.focus,
1292 );
1293 self.window.next_frame.focus = self.window.focus;
1294 self.window.next_frame.window_active = self.window.active.get();
1295
1296 // Register requested input handler with the platform window.
1297 if let Some(input_handler) = self.window.next_frame.input_handlers.pop() {
1298 self.window
1299 .platform_window
1300 .set_input_handler(input_handler.unwrap());
1301 }
1302
1303 self.window.layout_engine.as_mut().unwrap().clear();
1304 self.text_system().finish_frame();
1305 self.window
1306 .next_frame
1307 .finish(&mut self.window.rendered_frame);
1308 ELEMENT_ARENA.with_borrow_mut(|element_arena| {
1309 let percentage = (element_arena.len() as f32 / element_arena.capacity() as f32) * 100.;
1310 if percentage >= 80. {
1311 log::warn!("elevated element arena occupation: {}.", percentage);
1312 }
1313 element_arena.clear();
1314 });
1315
1316 self.window.draw_phase = DrawPhase::Focus;
1317 let previous_focus_path = self.window.rendered_frame.focus_path();
1318 let previous_window_active = self.window.rendered_frame.window_active;
1319 mem::swap(&mut self.window.rendered_frame, &mut self.window.next_frame);
1320 self.window.next_frame.clear();
1321 let current_focus_path = self.window.rendered_frame.focus_path();
1322 let current_window_active = self.window.rendered_frame.window_active;
1323
1324 if previous_focus_path != current_focus_path
1325 || previous_window_active != current_window_active
1326 {
1327 if !previous_focus_path.is_empty() && current_focus_path.is_empty() {
1328 self.window
1329 .focus_lost_listeners
1330 .clone()
1331 .retain(&(), |listener| listener(self));
1332 }
1333
1334 let event = FocusEvent {
1335 previous_focus_path: if previous_window_active {
1336 previous_focus_path
1337 } else {
1338 Default::default()
1339 },
1340 current_focus_path: if current_window_active {
1341 current_focus_path
1342 } else {
1343 Default::default()
1344 },
1345 };
1346 self.window
1347 .focus_listeners
1348 .clone()
1349 .retain(&(), |listener| listener(&event, self));
1350 }
1351
1352 self.reset_cursor_style();
1353 self.window.refreshing = false;
1354 self.window.draw_phase = DrawPhase::None;
1355 self.window.needs_present.set(true);
1356 }
1357
1358 #[profiling::function]
1359 fn present(&self) {
1360 self.window
1361 .platform_window
1362 .draw(&self.window.rendered_frame.scene);
1363 self.window.needs_present.set(false);
1364 profiling::finish_frame!();
1365 }
1366
1367 fn draw_roots(&mut self) {
1368 self.window.draw_phase = DrawPhase::Prepaint;
1369 self.window.tooltip_bounds.take();
1370
1371 // Layout all root elements.
1372 let mut root_element = self.window.root_view.as_ref().unwrap().clone().into_any();
1373 root_element.prepaint_as_root(Point::default(), self.window.viewport_size.into(), self);
1374
1375 let mut sorted_deferred_draws =
1376 (0..self.window.next_frame.deferred_draws.len()).collect::<SmallVec<[_; 8]>>();
1377 sorted_deferred_draws.sort_by_key(|ix| self.window.next_frame.deferred_draws[*ix].priority);
1378 self.prepaint_deferred_draws(&sorted_deferred_draws);
1379
1380 let mut prompt_element = None;
1381 let mut active_drag_element = None;
1382 let mut tooltip_element = None;
1383 if let Some(prompt) = self.window.prompt.take() {
1384 let mut element = prompt.view.any_view().into_any();
1385 element.prepaint_as_root(Point::default(), self.window.viewport_size.into(), self);
1386 prompt_element = Some(element);
1387 self.window.prompt = Some(prompt);
1388 } else if let Some(active_drag) = self.app.active_drag.take() {
1389 let mut element = active_drag.view.clone().into_any();
1390 let offset = self.mouse_position() - active_drag.cursor_offset;
1391 element.prepaint_as_root(offset, AvailableSpace::min_size(), self);
1392 active_drag_element = Some(element);
1393 self.app.active_drag = Some(active_drag);
1394 } else {
1395 tooltip_element = self.prepaint_tooltip();
1396 }
1397
1398 self.window.mouse_hit_test = self.window.next_frame.hit_test(self.window.mouse_position);
1399
1400 // Now actually paint the elements.
1401 self.window.draw_phase = DrawPhase::Paint;
1402 root_element.paint(self);
1403
1404 self.paint_deferred_draws(&sorted_deferred_draws);
1405
1406 if let Some(mut prompt_element) = prompt_element {
1407 prompt_element.paint(self)
1408 } else if let Some(mut drag_element) = active_drag_element {
1409 drag_element.paint(self);
1410 } else if let Some(mut tooltip_element) = tooltip_element {
1411 tooltip_element.paint(self);
1412 }
1413 }
1414
1415 fn prepaint_tooltip(&mut self) -> Option<AnyElement> {
1416 let tooltip_request = self.window.next_frame.tooltip_requests.last().cloned()?;
1417 let tooltip_request = tooltip_request.unwrap();
1418 let mut element = tooltip_request.tooltip.view.clone().into_any();
1419 let mouse_position = tooltip_request.tooltip.mouse_position;
1420 let tooltip_size = element.layout_as_root(AvailableSpace::min_size(), self);
1421
1422 let mut tooltip_bounds = Bounds::new(mouse_position + point(px(1.), px(1.)), tooltip_size);
1423 let window_bounds = Bounds {
1424 origin: Point::default(),
1425 size: self.viewport_size(),
1426 };
1427
1428 if tooltip_bounds.right() > window_bounds.right() {
1429 let new_x = mouse_position.x - tooltip_bounds.size.width - px(1.);
1430 if new_x >= Pixels::ZERO {
1431 tooltip_bounds.origin.x = new_x;
1432 } else {
1433 tooltip_bounds.origin.x = cmp::max(
1434 Pixels::ZERO,
1435 tooltip_bounds.origin.x - tooltip_bounds.right() - window_bounds.right(),
1436 );
1437 }
1438 }
1439
1440 if tooltip_bounds.bottom() > window_bounds.bottom() {
1441 let new_y = mouse_position.y - tooltip_bounds.size.height - px(1.);
1442 if new_y >= Pixels::ZERO {
1443 tooltip_bounds.origin.y = new_y;
1444 } else {
1445 tooltip_bounds.origin.y = cmp::max(
1446 Pixels::ZERO,
1447 tooltip_bounds.origin.y - tooltip_bounds.bottom() - window_bounds.bottom(),
1448 );
1449 }
1450 }
1451
1452 self.with_absolute_element_offset(tooltip_bounds.origin, |cx| element.prepaint(cx));
1453
1454 self.window.tooltip_bounds = Some(TooltipBounds {
1455 id: tooltip_request.id,
1456 bounds: tooltip_bounds,
1457 });
1458 Some(element)
1459 }
1460
1461 fn prepaint_deferred_draws(&mut self, deferred_draw_indices: &[usize]) {
1462 assert_eq!(self.window.element_id_stack.len(), 0);
1463
1464 let mut deferred_draws = mem::take(&mut self.window.next_frame.deferred_draws);
1465 for deferred_draw_ix in deferred_draw_indices {
1466 let deferred_draw = &mut deferred_draws[*deferred_draw_ix];
1467 self.window
1468 .element_id_stack
1469 .clone_from(&deferred_draw.element_id_stack);
1470 self.window
1471 .text_style_stack
1472 .clone_from(&deferred_draw.text_style_stack);
1473 self.window
1474 .next_frame
1475 .dispatch_tree
1476 .set_active_node(deferred_draw.parent_node);
1477
1478 let prepaint_start = self.prepaint_index();
1479 if let Some(element) = deferred_draw.element.as_mut() {
1480 self.with_absolute_element_offset(deferred_draw.absolute_offset, |cx| {
1481 element.prepaint(cx)
1482 });
1483 } else {
1484 self.reuse_prepaint(deferred_draw.prepaint_range.clone());
1485 }
1486 let prepaint_end = self.prepaint_index();
1487 deferred_draw.prepaint_range = prepaint_start..prepaint_end;
1488 }
1489 assert_eq!(
1490 self.window.next_frame.deferred_draws.len(),
1491 0,
1492 "cannot call defer_draw during deferred drawing"
1493 );
1494 self.window.next_frame.deferred_draws = deferred_draws;
1495 self.window.element_id_stack.clear();
1496 self.window.text_style_stack.clear();
1497 }
1498
1499 fn paint_deferred_draws(&mut self, deferred_draw_indices: &[usize]) {
1500 assert_eq!(self.window.element_id_stack.len(), 0);
1501
1502 let mut deferred_draws = mem::take(&mut self.window.next_frame.deferred_draws);
1503 for deferred_draw_ix in deferred_draw_indices {
1504 let mut deferred_draw = &mut deferred_draws[*deferred_draw_ix];
1505 self.window
1506 .element_id_stack
1507 .clone_from(&deferred_draw.element_id_stack);
1508 self.window
1509 .next_frame
1510 .dispatch_tree
1511 .set_active_node(deferred_draw.parent_node);
1512
1513 let paint_start = self.paint_index();
1514 if let Some(element) = deferred_draw.element.as_mut() {
1515 element.paint(self);
1516 } else {
1517 self.reuse_paint(deferred_draw.paint_range.clone());
1518 }
1519 let paint_end = self.paint_index();
1520 deferred_draw.paint_range = paint_start..paint_end;
1521 }
1522 self.window.next_frame.deferred_draws = deferred_draws;
1523 self.window.element_id_stack.clear();
1524 }
1525
1526 pub(crate) fn prepaint_index(&self) -> PrepaintStateIndex {
1527 PrepaintStateIndex {
1528 hitboxes_index: self.window.next_frame.hitboxes.len(),
1529 tooltips_index: self.window.next_frame.tooltip_requests.len(),
1530 deferred_draws_index: self.window.next_frame.deferred_draws.len(),
1531 dispatch_tree_index: self.window.next_frame.dispatch_tree.len(),
1532 accessed_element_states_index: self.window.next_frame.accessed_element_states.len(),
1533 line_layout_index: self.window.text_system.layout_index(),
1534 }
1535 }
1536
1537 pub(crate) fn reuse_prepaint(&mut self, range: Range<PrepaintStateIndex>) {
1538 let window = &mut self.window;
1539 window.next_frame.hitboxes.extend(
1540 window.rendered_frame.hitboxes[range.start.hitboxes_index..range.end.hitboxes_index]
1541 .iter()
1542 .cloned(),
1543 );
1544 window.next_frame.tooltip_requests.extend(
1545 window.rendered_frame.tooltip_requests
1546 [range.start.tooltips_index..range.end.tooltips_index]
1547 .iter_mut()
1548 .map(|request| request.take()),
1549 );
1550 window.next_frame.accessed_element_states.extend(
1551 window.rendered_frame.accessed_element_states[range.start.accessed_element_states_index
1552 ..range.end.accessed_element_states_index]
1553 .iter()
1554 .map(|(id, type_id)| (GlobalElementId(id.0.clone()), *type_id)),
1555 );
1556 window
1557 .text_system
1558 .reuse_layouts(range.start.line_layout_index..range.end.line_layout_index);
1559
1560 let reused_subtree = window.next_frame.dispatch_tree.reuse_subtree(
1561 range.start.dispatch_tree_index..range.end.dispatch_tree_index,
1562 &mut window.rendered_frame.dispatch_tree,
1563 );
1564 window.next_frame.deferred_draws.extend(
1565 window.rendered_frame.deferred_draws
1566 [range.start.deferred_draws_index..range.end.deferred_draws_index]
1567 .iter()
1568 .map(|deferred_draw| DeferredDraw {
1569 parent_node: reused_subtree.refresh_node_id(deferred_draw.parent_node),
1570 element_id_stack: deferred_draw.element_id_stack.clone(),
1571 text_style_stack: deferred_draw.text_style_stack.clone(),
1572 priority: deferred_draw.priority,
1573 element: None,
1574 absolute_offset: deferred_draw.absolute_offset,
1575 prepaint_range: deferred_draw.prepaint_range.clone(),
1576 paint_range: deferred_draw.paint_range.clone(),
1577 }),
1578 );
1579 }
1580
1581 pub(crate) fn paint_index(&self) -> PaintIndex {
1582 PaintIndex {
1583 scene_index: self.window.next_frame.scene.len(),
1584 mouse_listeners_index: self.window.next_frame.mouse_listeners.len(),
1585 input_handlers_index: self.window.next_frame.input_handlers.len(),
1586 cursor_styles_index: self.window.next_frame.cursor_styles.len(),
1587 accessed_element_states_index: self.window.next_frame.accessed_element_states.len(),
1588 line_layout_index: self.window.text_system.layout_index(),
1589 }
1590 }
1591
1592 pub(crate) fn reuse_paint(&mut self, range: Range<PaintIndex>) {
1593 let window = &mut self.window;
1594
1595 window.next_frame.cursor_styles.extend(
1596 window.rendered_frame.cursor_styles
1597 [range.start.cursor_styles_index..range.end.cursor_styles_index]
1598 .iter()
1599 .cloned(),
1600 );
1601 window.next_frame.input_handlers.extend(
1602 window.rendered_frame.input_handlers
1603 [range.start.input_handlers_index..range.end.input_handlers_index]
1604 .iter_mut()
1605 .map(|handler| handler.take()),
1606 );
1607 window.next_frame.mouse_listeners.extend(
1608 window.rendered_frame.mouse_listeners
1609 [range.start.mouse_listeners_index..range.end.mouse_listeners_index]
1610 .iter_mut()
1611 .map(|listener| listener.take()),
1612 );
1613 window.next_frame.accessed_element_states.extend(
1614 window.rendered_frame.accessed_element_states[range.start.accessed_element_states_index
1615 ..range.end.accessed_element_states_index]
1616 .iter()
1617 .map(|(id, type_id)| (GlobalElementId(id.0.clone()), *type_id)),
1618 );
1619 window
1620 .text_system
1621 .reuse_layouts(range.start.line_layout_index..range.end.line_layout_index);
1622 window.next_frame.scene.replay(
1623 range.start.scene_index..range.end.scene_index,
1624 &window.rendered_frame.scene,
1625 );
1626 }
1627
1628 /// Push a text style onto the stack, and call a function with that style active.
1629 /// Use [`AppContext::text_style`] to get the current, combined text style. This method
1630 /// should only be called as part of element drawing.
1631 pub fn with_text_style<F, R>(&mut self, style: Option<TextStyleRefinement>, f: F) -> R
1632 where
1633 F: FnOnce(&mut Self) -> R,
1634 {
1635 debug_assert!(
1636 matches!(
1637 self.window.draw_phase,
1638 DrawPhase::Prepaint | DrawPhase::Paint
1639 ),
1640 "this method can only be called during request_layout, prepaint, or paint"
1641 );
1642 if let Some(style) = style {
1643 self.window.text_style_stack.push(style);
1644 let result = f(self);
1645 self.window.text_style_stack.pop();
1646 result
1647 } else {
1648 f(self)
1649 }
1650 }
1651
1652 /// Updates the cursor style at the platform level. This method should only be called
1653 /// during the prepaint phase of element drawing.
1654 pub fn set_cursor_style(&mut self, style: CursorStyle, hitbox: &Hitbox) {
1655 debug_assert_eq!(
1656 self.window.draw_phase,
1657 DrawPhase::Paint,
1658 "this method can only be called during paint"
1659 );
1660 self.window
1661 .next_frame
1662 .cursor_styles
1663 .push(CursorStyleRequest {
1664 hitbox_id: hitbox.id,
1665 style,
1666 });
1667 }
1668
1669 /// Sets a tooltip to be rendered for the upcoming frame. This method should only be called
1670 /// during the paint phase of element drawing.
1671 pub fn set_tooltip(&mut self, tooltip: AnyTooltip) -> TooltipId {
1672 debug_assert_eq!(
1673 self.window.draw_phase,
1674 DrawPhase::Prepaint,
1675 "this method can only be called during prepaint"
1676 );
1677 let id = TooltipId(post_inc(&mut self.window.next_tooltip_id.0));
1678 self.window
1679 .next_frame
1680 .tooltip_requests
1681 .push(Some(TooltipRequest { id, tooltip }));
1682 id
1683 }
1684
1685 /// Invoke the given function with the given content mask after intersecting it
1686 /// with the current mask. This method should only be called during element drawing.
1687 pub fn with_content_mask<R>(
1688 &mut self,
1689 mask: Option<ContentMask<Pixels>>,
1690 f: impl FnOnce(&mut Self) -> R,
1691 ) -> R {
1692 debug_assert!(
1693 matches!(
1694 self.window.draw_phase,
1695 DrawPhase::Prepaint | DrawPhase::Paint
1696 ),
1697 "this method can only be called during request_layout, prepaint, or paint"
1698 );
1699 if let Some(mask) = mask {
1700 let mask = mask.intersect(&self.content_mask());
1701 self.window_mut().content_mask_stack.push(mask);
1702 let result = f(self);
1703 self.window_mut().content_mask_stack.pop();
1704 result
1705 } else {
1706 f(self)
1707 }
1708 }
1709
1710 /// Updates the global element offset relative to the current offset. This is used to implement
1711 /// scrolling. This method should only be called during the prepaint phase of element drawing.
1712 pub fn with_element_offset<R>(
1713 &mut self,
1714 offset: Point<Pixels>,
1715 f: impl FnOnce(&mut Self) -> R,
1716 ) -> R {
1717 debug_assert_eq!(
1718 self.window.draw_phase,
1719 DrawPhase::Prepaint,
1720 "this method can only be called during request_layout, or prepaint"
1721 );
1722
1723 if offset.is_zero() {
1724 return f(self);
1725 };
1726
1727 let abs_offset = self.element_offset() + offset;
1728 self.with_absolute_element_offset(abs_offset, f)
1729 }
1730
1731 /// Updates the global element offset based on the given offset. This is used to implement
1732 /// drag handles and other manual painting of elements. This method should only be called during
1733 /// the prepaint phase of element drawing.
1734 pub fn with_absolute_element_offset<R>(
1735 &mut self,
1736 offset: Point<Pixels>,
1737 f: impl FnOnce(&mut Self) -> R,
1738 ) -> R {
1739 debug_assert_eq!(
1740 self.window.draw_phase,
1741 DrawPhase::Prepaint,
1742 "this method can only be called during request_layout, or prepaint"
1743 );
1744 self.window_mut().element_offset_stack.push(offset);
1745 let result = f(self);
1746 self.window_mut().element_offset_stack.pop();
1747 result
1748 }
1749
1750 /// Perform prepaint on child elements in a "retryable" manner, so that any side effects
1751 /// of prepaints can be discarded before prepainting again. This is used to support autoscroll
1752 /// where we need to prepaint children to detect the autoscroll bounds, then adjust the
1753 /// element offset and prepaint again. See [`List`] for an example. This method should only be
1754 /// called during the prepaint phase of element drawing.
1755 pub fn transact<T, U>(&mut self, f: impl FnOnce(&mut Self) -> Result<T, U>) -> Result<T, U> {
1756 debug_assert_eq!(
1757 self.window.draw_phase,
1758 DrawPhase::Prepaint,
1759 "this method can only be called during prepaint"
1760 );
1761 let index = self.prepaint_index();
1762 let result = f(self);
1763 if result.is_err() {
1764 self.window
1765 .next_frame
1766 .hitboxes
1767 .truncate(index.hitboxes_index);
1768 self.window
1769 .next_frame
1770 .tooltip_requests
1771 .truncate(index.tooltips_index);
1772 self.window
1773 .next_frame
1774 .deferred_draws
1775 .truncate(index.deferred_draws_index);
1776 self.window
1777 .next_frame
1778 .dispatch_tree
1779 .truncate(index.dispatch_tree_index);
1780 self.window
1781 .next_frame
1782 .accessed_element_states
1783 .truncate(index.accessed_element_states_index);
1784 self.window
1785 .text_system
1786 .truncate_layouts(index.line_layout_index);
1787 }
1788 result
1789 }
1790
1791 /// When you call this method during [`prepaint`], containing elements will attempt to
1792 /// scroll to cause the specified bounds to become visible. When they decide to autoscroll, they will call
1793 /// [`prepaint`] again with a new set of bounds. See [`List`] for an example of an element
1794 /// that supports this method being called on the elements it contains. This method should only be
1795 /// called during the prepaint phase of element drawing.
1796 pub fn request_autoscroll(&mut self, bounds: Bounds<Pixels>) {
1797 debug_assert_eq!(
1798 self.window.draw_phase,
1799 DrawPhase::Prepaint,
1800 "this method can only be called during prepaint"
1801 );
1802 self.window.requested_autoscroll = Some(bounds);
1803 }
1804
1805 /// This method can be called from a containing element such as [`List`] to support the autoscroll behavior
1806 /// described in [`request_autoscroll`].
1807 pub fn take_autoscroll(&mut self) -> Option<Bounds<Pixels>> {
1808 debug_assert_eq!(
1809 self.window.draw_phase,
1810 DrawPhase::Prepaint,
1811 "this method can only be called during prepaint"
1812 );
1813 self.window.requested_autoscroll.take()
1814 }
1815
1816 /// Remove an asset from GPUI's cache
1817 pub fn remove_cached_asset<A: Asset + 'static>(
1818 &mut self,
1819 source: &A::Source,
1820 ) -> Option<A::Output> {
1821 self.asset_cache.remove::<A>(source)
1822 }
1823
1824 /// Asynchronously load an asset, if the asset hasn't finished loading this will return None.
1825 /// Your view will be re-drawn once the asset has finished loading.
1826 ///
1827 /// Note that the multiple calls to this method will only result in one `Asset::load` call.
1828 /// The results of that call will be cached, and returned on subsequent uses of this API.
1829 ///
1830 /// Use [Self::remove_cached_asset] to reload your asset.
1831 pub fn use_cached_asset<A: Asset + 'static>(
1832 &mut self,
1833 source: &A::Source,
1834 ) -> Option<A::Output> {
1835 self.asset_cache.get::<A>(source).or_else(|| {
1836 if let Some(asset) = self.use_asset::<A>(source) {
1837 self.asset_cache
1838 .insert::<A>(source.to_owned(), asset.clone());
1839 Some(asset)
1840 } else {
1841 None
1842 }
1843 })
1844 }
1845
1846 /// Asynchronously load an asset, if the asset hasn't finished loading this will return None.
1847 /// Your view will be re-drawn once the asset has finished loading.
1848 ///
1849 /// Note that the multiple calls to this method will only result in one `Asset::load` call at a
1850 /// time.
1851 ///
1852 /// This asset will not be cached by default, see [Self::use_cached_asset]
1853 pub fn use_asset<A: Asset + 'static>(&mut self, source: &A::Source) -> Option<A::Output> {
1854 let asset_id = (TypeId::of::<A>(), hash(source));
1855 let mut is_first = false;
1856 let task = self
1857 .loading_assets
1858 .remove(&asset_id)
1859 .map(|boxed_task| *boxed_task.downcast::<Shared<Task<A::Output>>>().unwrap())
1860 .unwrap_or_else(|| {
1861 is_first = true;
1862 let future = A::load(source.clone(), self);
1863 let task = self.background_executor().spawn(future).shared();
1864 task
1865 });
1866
1867 task.clone().now_or_never().or_else(|| {
1868 if is_first {
1869 let parent_id = self.parent_view_id();
1870 self.spawn({
1871 let task = task.clone();
1872 |mut cx| async move {
1873 task.await;
1874
1875 cx.on_next_frame(move |cx| {
1876 if let Some(parent_id) = parent_id {
1877 cx.notify(parent_id)
1878 } else {
1879 cx.refresh()
1880 }
1881 });
1882 }
1883 })
1884 .detach();
1885 }
1886
1887 self.loading_assets.insert(asset_id, Box::new(task));
1888
1889 None
1890 })
1891 }
1892
1893 /// Obtain the current element offset. This method should only be called during the
1894 /// prepaint phase of element drawing.
1895 pub fn element_offset(&self) -> Point<Pixels> {
1896 debug_assert_eq!(
1897 self.window.draw_phase,
1898 DrawPhase::Prepaint,
1899 "this method can only be called during prepaint"
1900 );
1901 self.window()
1902 .element_offset_stack
1903 .last()
1904 .copied()
1905 .unwrap_or_default()
1906 }
1907
1908 /// Obtain the current content mask. This method should only be called during element drawing.
1909 pub fn content_mask(&self) -> ContentMask<Pixels> {
1910 debug_assert!(
1911 matches!(
1912 self.window.draw_phase,
1913 DrawPhase::Prepaint | DrawPhase::Paint
1914 ),
1915 "this method can only be called during prepaint, or paint"
1916 );
1917 self.window()
1918 .content_mask_stack
1919 .last()
1920 .cloned()
1921 .unwrap_or_else(|| ContentMask {
1922 bounds: Bounds {
1923 origin: Point::default(),
1924 size: self.window().viewport_size,
1925 },
1926 })
1927 }
1928
1929 /// Provide elements in the called function with a new namespace in which their identiers must be unique.
1930 /// This can be used within a custom element to distinguish multiple sets of child elements.
1931 pub fn with_element_namespace<R>(
1932 &mut self,
1933 element_id: impl Into<ElementId>,
1934 f: impl FnOnce(&mut Self) -> R,
1935 ) -> R {
1936 self.window.element_id_stack.push(element_id.into());
1937 let result = f(self);
1938 self.window.element_id_stack.pop();
1939 result
1940 }
1941
1942 /// Updates or initializes state for an element with the given id that lives across multiple
1943 /// frames. If an element with this ID existed in the rendered frame, its state will be passed
1944 /// to the given closure. The state returned by the closure will be stored so it can be referenced
1945 /// when drawing the next frame. This method should only be called as part of element drawing.
1946 pub fn with_element_state<S, R>(
1947 &mut self,
1948 global_id: &GlobalElementId,
1949 f: impl FnOnce(Option<S>, &mut Self) -> (R, S),
1950 ) -> R
1951 where
1952 S: 'static,
1953 {
1954 debug_assert!(
1955 matches!(
1956 self.window.draw_phase,
1957 DrawPhase::Prepaint | DrawPhase::Paint
1958 ),
1959 "this method can only be called during request_layout, prepaint, or paint"
1960 );
1961
1962 let key = (GlobalElementId(global_id.0.clone()), TypeId::of::<S>());
1963 self.window
1964 .next_frame
1965 .accessed_element_states
1966 .push((GlobalElementId(key.0.clone()), TypeId::of::<S>()));
1967
1968 if let Some(any) = self
1969 .window
1970 .next_frame
1971 .element_states
1972 .remove(&key)
1973 .or_else(|| self.window.rendered_frame.element_states.remove(&key))
1974 {
1975 let ElementStateBox {
1976 inner,
1977 #[cfg(debug_assertions)]
1978 type_name,
1979 } = any;
1980 // Using the extra inner option to avoid needing to reallocate a new box.
1981 let mut state_box = inner
1982 .downcast::<Option<S>>()
1983 .map_err(|_| {
1984 #[cfg(debug_assertions)]
1985 {
1986 anyhow::anyhow!(
1987 "invalid element state type for id, requested {:?}, actual: {:?}",
1988 std::any::type_name::<S>(),
1989 type_name
1990 )
1991 }
1992
1993 #[cfg(not(debug_assertions))]
1994 {
1995 anyhow::anyhow!(
1996 "invalid element state type for id, requested {:?}",
1997 std::any::type_name::<S>(),
1998 )
1999 }
2000 })
2001 .unwrap();
2002
2003 let state = state_box.take().expect(
2004 "reentrant call to with_element_state for the same state type and element id",
2005 );
2006 let (result, state) = f(Some(state), self);
2007 state_box.replace(state);
2008 self.window.next_frame.element_states.insert(
2009 key,
2010 ElementStateBox {
2011 inner: state_box,
2012 #[cfg(debug_assertions)]
2013 type_name,
2014 },
2015 );
2016 result
2017 } else {
2018 let (result, state) = f(None, self);
2019 self.window.next_frame.element_states.insert(
2020 key,
2021 ElementStateBox {
2022 inner: Box::new(Some(state)),
2023 #[cfg(debug_assertions)]
2024 type_name: std::any::type_name::<S>(),
2025 },
2026 );
2027 result
2028 }
2029 }
2030
2031 /// A variant of `with_element_state` that allows the element's id to be optional. This is a convenience
2032 /// method for elements where the element id may or may not be assigned. Prefer using `with_element_state`
2033 /// when the element is guaranteed to have an id.
2034 pub fn with_optional_element_state<S, R>(
2035 &mut self,
2036 global_id: Option<&GlobalElementId>,
2037 f: impl FnOnce(Option<Option<S>>, &mut Self) -> (R, Option<S>),
2038 ) -> R
2039 where
2040 S: 'static,
2041 {
2042 debug_assert!(
2043 matches!(
2044 self.window.draw_phase,
2045 DrawPhase::Prepaint | DrawPhase::Paint
2046 ),
2047 "this method can only be called during request_layout, prepaint, or paint"
2048 );
2049
2050 if let Some(global_id) = global_id {
2051 self.with_element_state(global_id, |state, cx| {
2052 let (result, state) = f(Some(state), cx);
2053 let state =
2054 state.expect("you must return some state when you pass some element id");
2055 (result, state)
2056 })
2057 } else {
2058 let (result, state) = f(None, self);
2059 debug_assert!(
2060 state.is_none(),
2061 "you must not return an element state when passing None for the global id"
2062 );
2063 result
2064 }
2065 }
2066
2067 /// Defers the drawing of the given element, scheduling it to be painted on top of the currently-drawn tree
2068 /// at a later time. The `priority` parameter determines the drawing order relative to other deferred elements,
2069 /// with higher values being drawn on top.
2070 ///
2071 /// This method should only be called as part of the prepaint phase of element drawing.
2072 pub fn defer_draw(
2073 &mut self,
2074 element: AnyElement,
2075 absolute_offset: Point<Pixels>,
2076 priority: usize,
2077 ) {
2078 let window = &mut self.window;
2079 debug_assert_eq!(
2080 window.draw_phase,
2081 DrawPhase::Prepaint,
2082 "this method can only be called during request_layout or prepaint"
2083 );
2084 let parent_node = window.next_frame.dispatch_tree.active_node_id().unwrap();
2085 window.next_frame.deferred_draws.push(DeferredDraw {
2086 parent_node,
2087 element_id_stack: window.element_id_stack.clone(),
2088 text_style_stack: window.text_style_stack.clone(),
2089 priority,
2090 element: Some(element),
2091 absolute_offset,
2092 prepaint_range: PrepaintStateIndex::default()..PrepaintStateIndex::default(),
2093 paint_range: PaintIndex::default()..PaintIndex::default(),
2094 });
2095 }
2096
2097 /// Creates a new painting layer for the specified bounds. A "layer" is a batch
2098 /// of geometry that are non-overlapping and have the same draw order. This is typically used
2099 /// for performance reasons.
2100 ///
2101 /// This method should only be called as part of the paint phase of element drawing.
2102 pub fn paint_layer<R>(&mut self, bounds: Bounds<Pixels>, f: impl FnOnce(&mut Self) -> R) -> R {
2103 debug_assert_eq!(
2104 self.window.draw_phase,
2105 DrawPhase::Paint,
2106 "this method can only be called during paint"
2107 );
2108
2109 let scale_factor = self.scale_factor();
2110 let content_mask = self.content_mask();
2111 let clipped_bounds = bounds.intersect(&content_mask.bounds);
2112 if !clipped_bounds.is_empty() {
2113 self.window
2114 .next_frame
2115 .scene
2116 .push_layer(clipped_bounds.scale(scale_factor));
2117 }
2118
2119 let result = f(self);
2120
2121 if !clipped_bounds.is_empty() {
2122 self.window.next_frame.scene.pop_layer();
2123 }
2124
2125 result
2126 }
2127
2128 /// Paint one or more drop shadows into the scene for the next frame at the current z-index.
2129 ///
2130 /// This method should only be called as part of the paint phase of element drawing.
2131 pub fn paint_shadows(
2132 &mut self,
2133 bounds: Bounds<Pixels>,
2134 corner_radii: Corners<Pixels>,
2135 shadows: &[BoxShadow],
2136 ) {
2137 debug_assert_eq!(
2138 self.window.draw_phase,
2139 DrawPhase::Paint,
2140 "this method can only be called during paint"
2141 );
2142
2143 let scale_factor = self.scale_factor();
2144 let content_mask = self.content_mask();
2145 for shadow in shadows {
2146 let mut shadow_bounds = bounds;
2147 shadow_bounds.origin += shadow.offset;
2148 shadow_bounds.dilate(shadow.spread_radius);
2149 self.window.next_frame.scene.insert_primitive(Shadow {
2150 order: 0,
2151 blur_radius: shadow.blur_radius.scale(scale_factor),
2152 bounds: shadow_bounds.scale(scale_factor),
2153 content_mask: content_mask.scale(scale_factor),
2154 corner_radii: corner_radii.scale(scale_factor),
2155 color: shadow.color,
2156 });
2157 }
2158 }
2159
2160 /// Paint one or more quads into the scene for the next frame at the current stacking context.
2161 /// Quads are colored rectangular regions with an optional background, border, and corner radius.
2162 /// see [`fill`](crate::fill), [`outline`](crate::outline), and [`quad`](crate::quad) to construct this type.
2163 ///
2164 /// This method should only be called as part of the paint phase of element drawing.
2165 pub fn paint_quad(&mut self, quad: PaintQuad) {
2166 debug_assert_eq!(
2167 self.window.draw_phase,
2168 DrawPhase::Paint,
2169 "this method can only be called during paint"
2170 );
2171
2172 let scale_factor = self.scale_factor();
2173 let content_mask = self.content_mask();
2174 self.window.next_frame.scene.insert_primitive(Quad {
2175 order: 0,
2176 pad: 0,
2177 bounds: quad.bounds.scale(scale_factor),
2178 content_mask: content_mask.scale(scale_factor),
2179 background: quad.background,
2180 border_color: quad.border_color,
2181 corner_radii: quad.corner_radii.scale(scale_factor),
2182 border_widths: quad.border_widths.scale(scale_factor),
2183 });
2184 }
2185
2186 /// Paint the given `Path` into the scene for the next frame at the current z-index.
2187 ///
2188 /// This method should only be called as part of the paint phase of element drawing.
2189 pub fn paint_path(&mut self, mut path: Path<Pixels>, color: impl Into<Hsla>) {
2190 debug_assert_eq!(
2191 self.window.draw_phase,
2192 DrawPhase::Paint,
2193 "this method can only be called during paint"
2194 );
2195
2196 let scale_factor = self.scale_factor();
2197 let content_mask = self.content_mask();
2198 path.content_mask = content_mask;
2199 path.color = color.into();
2200 self.window
2201 .next_frame
2202 .scene
2203 .insert_primitive(path.scale(scale_factor));
2204 }
2205
2206 /// Paint an underline into the scene for the next frame at the current z-index.
2207 ///
2208 /// This method should only be called as part of the paint phase of element drawing.
2209 pub fn paint_underline(
2210 &mut self,
2211 origin: Point<Pixels>,
2212 width: Pixels,
2213 style: &UnderlineStyle,
2214 ) {
2215 debug_assert_eq!(
2216 self.window.draw_phase,
2217 DrawPhase::Paint,
2218 "this method can only be called during paint"
2219 );
2220
2221 let scale_factor = self.scale_factor();
2222 let height = if style.wavy {
2223 style.thickness * 3.
2224 } else {
2225 style.thickness
2226 };
2227 let bounds = Bounds {
2228 origin,
2229 size: size(width, height),
2230 };
2231 let content_mask = self.content_mask();
2232
2233 self.window.next_frame.scene.insert_primitive(Underline {
2234 order: 0,
2235 pad: 0,
2236 bounds: bounds.scale(scale_factor),
2237 content_mask: content_mask.scale(scale_factor),
2238 color: style.color.unwrap_or_default(),
2239 thickness: style.thickness.scale(scale_factor),
2240 wavy: style.wavy,
2241 });
2242 }
2243
2244 /// Paint a strikethrough into the scene for the next frame at the current z-index.
2245 ///
2246 /// This method should only be called as part of the paint phase of element drawing.
2247 pub fn paint_strikethrough(
2248 &mut self,
2249 origin: Point<Pixels>,
2250 width: Pixels,
2251 style: &StrikethroughStyle,
2252 ) {
2253 debug_assert_eq!(
2254 self.window.draw_phase,
2255 DrawPhase::Paint,
2256 "this method can only be called during paint"
2257 );
2258
2259 let scale_factor = self.scale_factor();
2260 let height = style.thickness;
2261 let bounds = Bounds {
2262 origin,
2263 size: size(width, height),
2264 };
2265 let content_mask = self.content_mask();
2266
2267 self.window.next_frame.scene.insert_primitive(Underline {
2268 order: 0,
2269 pad: 0,
2270 bounds: bounds.scale(scale_factor),
2271 content_mask: content_mask.scale(scale_factor),
2272 thickness: style.thickness.scale(scale_factor),
2273 color: style.color.unwrap_or_default(),
2274 wavy: false,
2275 });
2276 }
2277
2278 /// Paints a monochrome (non-emoji) glyph into the scene for the next frame at the current z-index.
2279 ///
2280 /// The y component of the origin is the baseline of the glyph.
2281 /// You should generally prefer to use the [`ShapedLine::paint`](crate::ShapedLine::paint) or
2282 /// [`WrappedLine::paint`](crate::WrappedLine::paint) methods in the [`TextSystem`](crate::TextSystem).
2283 /// This method is only useful if you need to paint a single glyph that has already been shaped.
2284 ///
2285 /// This method should only be called as part of the paint phase of element drawing.
2286 pub fn paint_glyph(
2287 &mut self,
2288 origin: Point<Pixels>,
2289 font_id: FontId,
2290 glyph_id: GlyphId,
2291 font_size: Pixels,
2292 color: Hsla,
2293 ) -> Result<()> {
2294 debug_assert_eq!(
2295 self.window.draw_phase,
2296 DrawPhase::Paint,
2297 "this method can only be called during paint"
2298 );
2299
2300 let scale_factor = self.scale_factor();
2301 let glyph_origin = origin.scale(scale_factor);
2302 let subpixel_variant = Point {
2303 x: (glyph_origin.x.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
2304 y: (glyph_origin.y.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
2305 };
2306 let params = RenderGlyphParams {
2307 font_id,
2308 glyph_id,
2309 font_size,
2310 subpixel_variant,
2311 scale_factor,
2312 is_emoji: false,
2313 };
2314
2315 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
2316 if !raster_bounds.is_zero() {
2317 let tile =
2318 self.window
2319 .sprite_atlas
2320 .get_or_insert_with(¶ms.clone().into(), &mut || {
2321 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
2322 Ok((size, Cow::Owned(bytes)))
2323 })?;
2324 let bounds = Bounds {
2325 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
2326 size: tile.bounds.size.map(Into::into),
2327 };
2328 let content_mask = self.content_mask().scale(scale_factor);
2329 self.window
2330 .next_frame
2331 .scene
2332 .insert_primitive(MonochromeSprite {
2333 order: 0,
2334 pad: 0,
2335 bounds,
2336 content_mask,
2337 color,
2338 tile,
2339 transformation: TransformationMatrix::unit(),
2340 });
2341 }
2342 Ok(())
2343 }
2344
2345 /// Paints an emoji glyph into the scene for the next frame at the current z-index.
2346 ///
2347 /// The y component of the origin is the baseline of the glyph.
2348 /// You should generally prefer to use the [`ShapedLine::paint`](crate::ShapedLine::paint) or
2349 /// [`WrappedLine::paint`](crate::WrappedLine::paint) methods in the [`TextSystem`](crate::TextSystem).
2350 /// This method is only useful if you need to paint a single emoji that has already been shaped.
2351 ///
2352 /// This method should only be called as part of the paint phase of element drawing.
2353 pub fn paint_emoji(
2354 &mut self,
2355 origin: Point<Pixels>,
2356 font_id: FontId,
2357 glyph_id: GlyphId,
2358 font_size: Pixels,
2359 ) -> Result<()> {
2360 debug_assert_eq!(
2361 self.window.draw_phase,
2362 DrawPhase::Paint,
2363 "this method can only be called during paint"
2364 );
2365
2366 let scale_factor = self.scale_factor();
2367 let glyph_origin = origin.scale(scale_factor);
2368 let params = RenderGlyphParams {
2369 font_id,
2370 glyph_id,
2371 font_size,
2372 // We don't render emojis with subpixel variants.
2373 subpixel_variant: Default::default(),
2374 scale_factor,
2375 is_emoji: true,
2376 };
2377
2378 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
2379 if !raster_bounds.is_zero() {
2380 let tile =
2381 self.window
2382 .sprite_atlas
2383 .get_or_insert_with(¶ms.clone().into(), &mut || {
2384 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
2385 Ok((size, Cow::Owned(bytes)))
2386 })?;
2387 let bounds = Bounds {
2388 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
2389 size: tile.bounds.size.map(Into::into),
2390 };
2391 let content_mask = self.content_mask().scale(scale_factor);
2392
2393 self.window
2394 .next_frame
2395 .scene
2396 .insert_primitive(PolychromeSprite {
2397 order: 0,
2398 grayscale: false,
2399 bounds,
2400 corner_radii: Default::default(),
2401 content_mask,
2402 tile,
2403 });
2404 }
2405 Ok(())
2406 }
2407
2408 /// Paint a monochrome SVG into the scene for the next frame at the current stacking context.
2409 ///
2410 /// This method should only be called as part of the paint phase of element drawing.
2411 pub fn paint_svg(
2412 &mut self,
2413 bounds: Bounds<Pixels>,
2414 path: SharedString,
2415 transformation: TransformationMatrix,
2416 color: Hsla,
2417 ) -> Result<()> {
2418 debug_assert_eq!(
2419 self.window.draw_phase,
2420 DrawPhase::Paint,
2421 "this method can only be called during paint"
2422 );
2423
2424 let scale_factor = self.scale_factor();
2425 let bounds = bounds.scale(scale_factor);
2426 // Render the SVG at twice the size to get a higher quality result.
2427 let params = RenderSvgParams {
2428 path,
2429 size: bounds
2430 .size
2431 .map(|pixels| DevicePixels::from((pixels.0 * 2.).ceil() as i32)),
2432 };
2433
2434 let tile =
2435 self.window
2436 .sprite_atlas
2437 .get_or_insert_with(¶ms.clone().into(), &mut || {
2438 let bytes = self.svg_renderer.render(¶ms)?;
2439 Ok((params.size, Cow::Owned(bytes)))
2440 })?;
2441 let content_mask = self.content_mask().scale(scale_factor);
2442
2443 self.window
2444 .next_frame
2445 .scene
2446 .insert_primitive(MonochromeSprite {
2447 order: 0,
2448 pad: 0,
2449 bounds,
2450 content_mask,
2451 color,
2452 tile,
2453 transformation,
2454 });
2455
2456 Ok(())
2457 }
2458
2459 /// Paint an image into the scene for the next frame at the current z-index.
2460 ///
2461 /// This method should only be called as part of the paint phase of element drawing.
2462 pub fn paint_image(
2463 &mut self,
2464 bounds: Bounds<Pixels>,
2465 corner_radii: Corners<Pixels>,
2466 data: Arc<ImageData>,
2467 grayscale: bool,
2468 ) -> Result<()> {
2469 debug_assert_eq!(
2470 self.window.draw_phase,
2471 DrawPhase::Paint,
2472 "this method can only be called during paint"
2473 );
2474
2475 let scale_factor = self.scale_factor();
2476 let bounds = bounds.scale(scale_factor);
2477 let params = RenderImageParams { image_id: data.id };
2478
2479 let tile = self
2480 .window
2481 .sprite_atlas
2482 .get_or_insert_with(¶ms.clone().into(), &mut || {
2483 Ok((data.size(), Cow::Borrowed(data.as_bytes())))
2484 })?;
2485 let content_mask = self.content_mask().scale(scale_factor);
2486 let corner_radii = corner_radii.scale(scale_factor);
2487
2488 self.window
2489 .next_frame
2490 .scene
2491 .insert_primitive(PolychromeSprite {
2492 order: 0,
2493 grayscale,
2494 bounds,
2495 content_mask,
2496 corner_radii,
2497 tile,
2498 });
2499 Ok(())
2500 }
2501
2502 /// Paint a surface into the scene for the next frame at the current z-index.
2503 ///
2504 /// This method should only be called as part of the paint phase of element drawing.
2505 #[cfg(target_os = "macos")]
2506 pub fn paint_surface(&mut self, bounds: Bounds<Pixels>, image_buffer: CVImageBuffer) {
2507 debug_assert_eq!(
2508 self.window.draw_phase,
2509 DrawPhase::Paint,
2510 "this method can only be called during paint"
2511 );
2512
2513 let scale_factor = self.scale_factor();
2514 let bounds = bounds.scale(scale_factor);
2515 let content_mask = self.content_mask().scale(scale_factor);
2516 self.window
2517 .next_frame
2518 .scene
2519 .insert_primitive(crate::Surface {
2520 order: 0,
2521 bounds,
2522 content_mask,
2523 image_buffer,
2524 });
2525 }
2526
2527 #[must_use]
2528 /// Add a node to the layout tree for the current frame. Takes the `Style` of the element for which
2529 /// layout is being requested, along with the layout ids of any children. This method is called during
2530 /// calls to the [`Element::request_layout`] trait method and enables any element to participate in layout.
2531 ///
2532 /// This method should only be called as part of the request_layout or prepaint phase of element drawing.
2533 pub fn request_layout(
2534 &mut self,
2535 style: Style,
2536 children: impl IntoIterator<Item = LayoutId>,
2537 ) -> LayoutId {
2538 debug_assert_eq!(
2539 self.window.draw_phase,
2540 DrawPhase::Prepaint,
2541 "this method can only be called during request_layout, or prepaint"
2542 );
2543
2544 self.app.layout_id_buffer.clear();
2545 self.app.layout_id_buffer.extend(children);
2546 let rem_size = self.rem_size();
2547
2548 self.window.layout_engine.as_mut().unwrap().request_layout(
2549 style,
2550 rem_size,
2551 &self.app.layout_id_buffer,
2552 )
2553 }
2554
2555 /// Add a node to the layout tree for the current frame. Instead of taking a `Style` and children,
2556 /// this variant takes a function that is invoked during layout so you can use arbitrary logic to
2557 /// determine the element's size. One place this is used internally is when measuring text.
2558 ///
2559 /// The given closure is invoked at layout time with the known dimensions and available space and
2560 /// returns a `Size`.
2561 ///
2562 /// This method should only be called as part of the request_layout or prepaint phase of element drawing.
2563 pub fn request_measured_layout<
2564 F: FnMut(Size<Option<Pixels>>, Size<AvailableSpace>, &mut WindowContext) -> Size<Pixels>
2565 + 'static,
2566 >(
2567 &mut self,
2568 style: Style,
2569 measure: F,
2570 ) -> LayoutId {
2571 debug_assert_eq!(
2572 self.window.draw_phase,
2573 DrawPhase::Prepaint,
2574 "this method can only be called during request_layout, or prepaint"
2575 );
2576
2577 let rem_size = self.rem_size();
2578 self.window
2579 .layout_engine
2580 .as_mut()
2581 .unwrap()
2582 .request_measured_layout(style, rem_size, measure)
2583 }
2584
2585 /// Compute the layout for the given id within the given available space.
2586 /// This method is called for its side effect, typically by the framework prior to painting.
2587 /// After calling it, you can request the bounds of the given layout node id or any descendant.
2588 ///
2589 /// This method should only be called as part of the prepaint phase of element drawing.
2590 pub fn compute_layout(&mut self, layout_id: LayoutId, available_space: Size<AvailableSpace>) {
2591 debug_assert_eq!(
2592 self.window.draw_phase,
2593 DrawPhase::Prepaint,
2594 "this method can only be called during request_layout, or prepaint"
2595 );
2596
2597 let mut layout_engine = self.window.layout_engine.take().unwrap();
2598 layout_engine.compute_layout(layout_id, available_space, self);
2599 self.window.layout_engine = Some(layout_engine);
2600 }
2601
2602 /// Obtain the bounds computed for the given LayoutId relative to the window. This method will usually be invoked by
2603 /// GPUI itself automatically in order to pass your element its `Bounds` automatically.
2604 ///
2605 /// This method should only be called as part of element drawing.
2606 pub fn layout_bounds(&mut self, layout_id: LayoutId) -> Bounds<Pixels> {
2607 debug_assert_eq!(
2608 self.window.draw_phase,
2609 DrawPhase::Prepaint,
2610 "this method can only be called during request_layout, prepaint, or paint"
2611 );
2612
2613 let mut bounds = self
2614 .window
2615 .layout_engine
2616 .as_mut()
2617 .unwrap()
2618 .layout_bounds(layout_id)
2619 .map(Into::into);
2620 bounds.origin += self.element_offset();
2621 bounds
2622 }
2623
2624 /// This method should be called during `prepaint`. You can use
2625 /// the returned [Hitbox] during `paint` or in an event handler
2626 /// to determine whether the inserted hitbox was the topmost.
2627 ///
2628 /// This method should only be called as part of the prepaint phase of element drawing.
2629 pub fn insert_hitbox(&mut self, bounds: Bounds<Pixels>, opaque: bool) -> Hitbox {
2630 debug_assert_eq!(
2631 self.window.draw_phase,
2632 DrawPhase::Prepaint,
2633 "this method can only be called during prepaint"
2634 );
2635
2636 let content_mask = self.content_mask();
2637 let window = &mut self.window;
2638 let id = window.next_hitbox_id;
2639 window.next_hitbox_id.0 += 1;
2640 let hitbox = Hitbox {
2641 id,
2642 bounds,
2643 content_mask,
2644 opaque,
2645 };
2646 window.next_frame.hitboxes.push(hitbox.clone());
2647 hitbox
2648 }
2649
2650 /// Sets the key context for the current element. This context will be used to translate
2651 /// keybindings into actions.
2652 ///
2653 /// This method should only be called as part of the paint phase of element drawing.
2654 pub fn set_key_context(&mut self, context: KeyContext) {
2655 debug_assert_eq!(
2656 self.window.draw_phase,
2657 DrawPhase::Paint,
2658 "this method can only be called during paint"
2659 );
2660 self.window
2661 .next_frame
2662 .dispatch_tree
2663 .set_key_context(context);
2664 }
2665
2666 /// Sets the focus handle for the current element. This handle will be used to manage focus state
2667 /// and keyboard event dispatch for the element.
2668 ///
2669 /// This method should only be called as part of the paint phase of element drawing.
2670 pub fn set_focus_handle(&mut self, focus_handle: &FocusHandle) {
2671 debug_assert_eq!(
2672 self.window.draw_phase,
2673 DrawPhase::Paint,
2674 "this method can only be called during paint"
2675 );
2676 self.window
2677 .next_frame
2678 .dispatch_tree
2679 .set_focus_id(focus_handle.id);
2680 }
2681
2682 /// Sets the view id for the current element, which will be used to manage view caching.
2683 ///
2684 /// This method should only be called as part of element prepaint. We plan on removing this
2685 /// method eventually when we solve some issues that require us to construct editor elements
2686 /// directly instead of always using editors via views.
2687 pub fn set_view_id(&mut self, view_id: EntityId) {
2688 debug_assert_eq!(
2689 self.window.draw_phase,
2690 DrawPhase::Prepaint,
2691 "this method can only be called during prepaint"
2692 );
2693 self.window.next_frame.dispatch_tree.set_view_id(view_id);
2694 }
2695
2696 /// Get the last view id for the current element
2697 pub fn parent_view_id(&mut self) -> Option<EntityId> {
2698 self.window.next_frame.dispatch_tree.parent_view_id()
2699 }
2700
2701 /// Sets an input handler, such as [`ElementInputHandler`][element_input_handler], which interfaces with the
2702 /// platform to receive textual input with proper integration with concerns such
2703 /// as IME interactions. This handler will be active for the upcoming frame until the following frame is
2704 /// rendered.
2705 ///
2706 /// This method should only be called as part of the paint phase of element drawing.
2707 ///
2708 /// [element_input_handler]: crate::ElementInputHandler
2709 pub fn handle_input(&mut self, focus_handle: &FocusHandle, input_handler: impl InputHandler) {
2710 debug_assert_eq!(
2711 self.window.draw_phase,
2712 DrawPhase::Paint,
2713 "this method can only be called during paint"
2714 );
2715
2716 if focus_handle.is_focused(self) {
2717 let cx = self.to_async();
2718 self.window
2719 .next_frame
2720 .input_handlers
2721 .push(Some(PlatformInputHandler::new(cx, Box::new(input_handler))));
2722 }
2723 }
2724
2725 /// Register a mouse event listener on the window for the next frame. The type of event
2726 /// is determined by the first parameter of the given listener. When the next frame is rendered
2727 /// the listener will be cleared.
2728 ///
2729 /// This method should only be called as part of the paint phase of element drawing.
2730 pub fn on_mouse_event<Event: MouseEvent>(
2731 &mut self,
2732 mut handler: impl FnMut(&Event, DispatchPhase, &mut WindowContext) + 'static,
2733 ) {
2734 debug_assert_eq!(
2735 self.window.draw_phase,
2736 DrawPhase::Paint,
2737 "this method can only be called during paint"
2738 );
2739
2740 self.window.next_frame.mouse_listeners.push(Some(Box::new(
2741 move |event: &dyn Any, phase: DispatchPhase, cx: &mut WindowContext<'_>| {
2742 if let Some(event) = event.downcast_ref() {
2743 handler(event, phase, cx)
2744 }
2745 },
2746 )));
2747 }
2748
2749 /// Register a key event listener on the window for the next frame. The type of event
2750 /// is determined by the first parameter of the given listener. When the next frame is rendered
2751 /// the listener will be cleared.
2752 ///
2753 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
2754 /// a specific need to register a global listener.
2755 ///
2756 /// This method should only be called as part of the paint phase of element drawing.
2757 pub fn on_key_event<Event: KeyEvent>(
2758 &mut self,
2759 listener: impl Fn(&Event, DispatchPhase, &mut WindowContext) + 'static,
2760 ) {
2761 debug_assert_eq!(
2762 self.window.draw_phase,
2763 DrawPhase::Paint,
2764 "this method can only be called during paint"
2765 );
2766
2767 self.window.next_frame.dispatch_tree.on_key_event(Rc::new(
2768 move |event: &dyn Any, phase, cx: &mut WindowContext<'_>| {
2769 if let Some(event) = event.downcast_ref::<Event>() {
2770 listener(event, phase, cx)
2771 }
2772 },
2773 ));
2774 }
2775
2776 /// Register a modifiers changed event listener on the window for the next frame.
2777 ///
2778 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
2779 /// a specific need to register a global listener.
2780 ///
2781 /// This method should only be called as part of the paint phase of element drawing.
2782 pub fn on_modifiers_changed(
2783 &mut self,
2784 listener: impl Fn(&ModifiersChangedEvent, &mut WindowContext) + 'static,
2785 ) {
2786 debug_assert_eq!(
2787 self.window.draw_phase,
2788 DrawPhase::Paint,
2789 "this method can only be called during paint"
2790 );
2791
2792 self.window
2793 .next_frame
2794 .dispatch_tree
2795 .on_modifiers_changed(Rc::new(
2796 move |event: &ModifiersChangedEvent, cx: &mut WindowContext<'_>| {
2797 listener(event, cx)
2798 },
2799 ));
2800 }
2801
2802 fn reset_cursor_style(&self) {
2803 // Set the cursor only if we're the active window.
2804 if self.is_window_active() {
2805 let style = self
2806 .window
2807 .rendered_frame
2808 .cursor_styles
2809 .iter()
2810 .rev()
2811 .find(|request| request.hitbox_id.is_hovered(self))
2812 .map(|request| request.style)
2813 .unwrap_or(CursorStyle::Arrow);
2814 self.platform.set_cursor_style(style);
2815 }
2816 }
2817
2818 /// Dispatch a given keystroke as though the user had typed it.
2819 /// You can create a keystroke with Keystroke::parse("").
2820 pub fn dispatch_keystroke(&mut self, keystroke: Keystroke) -> bool {
2821 let keystroke = keystroke.with_simulated_ime();
2822 let result = self.dispatch_event(PlatformInput::KeyDown(KeyDownEvent {
2823 keystroke: keystroke.clone(),
2824 is_held: false,
2825 }));
2826 if !result.propagate {
2827 return true;
2828 }
2829
2830 if let Some(input) = keystroke.ime_key {
2831 if let Some(mut input_handler) = self.window.platform_window.take_input_handler() {
2832 input_handler.dispatch_input(&input, self);
2833 self.window.platform_window.set_input_handler(input_handler);
2834 return true;
2835 }
2836 }
2837
2838 false
2839 }
2840
2841 /// Represent this action as a key binding string, to display in the UI.
2842 pub fn keystroke_text_for(&self, action: &dyn Action) -> String {
2843 self.bindings_for_action(action)
2844 .into_iter()
2845 .next()
2846 .map(|binding| {
2847 binding
2848 .keystrokes()
2849 .iter()
2850 .map(ToString::to_string)
2851 .collect::<Vec<_>>()
2852 .join(" ")
2853 })
2854 .unwrap_or_else(|| action.name().to_string())
2855 }
2856
2857 /// Dispatch a mouse or keyboard event on the window.
2858 #[profiling::function]
2859 pub fn dispatch_event(&mut self, event: PlatformInput) -> DispatchEventResult {
2860 self.window.last_input_timestamp.set(Instant::now());
2861 // Handlers may set this to false by calling `stop_propagation`.
2862 self.app.propagate_event = true;
2863 // Handlers may set this to true by calling `prevent_default`.
2864 self.window.default_prevented = false;
2865
2866 let event = match event {
2867 // Track the mouse position with our own state, since accessing the platform
2868 // API for the mouse position can only occur on the main thread.
2869 PlatformInput::MouseMove(mouse_move) => {
2870 self.window.mouse_position = mouse_move.position;
2871 self.window.modifiers = mouse_move.modifiers;
2872 PlatformInput::MouseMove(mouse_move)
2873 }
2874 PlatformInput::MouseDown(mouse_down) => {
2875 self.window.mouse_position = mouse_down.position;
2876 self.window.modifiers = mouse_down.modifiers;
2877 PlatformInput::MouseDown(mouse_down)
2878 }
2879 PlatformInput::MouseUp(mouse_up) => {
2880 self.window.mouse_position = mouse_up.position;
2881 self.window.modifiers = mouse_up.modifiers;
2882 PlatformInput::MouseUp(mouse_up)
2883 }
2884 PlatformInput::MouseExited(mouse_exited) => {
2885 self.window.modifiers = mouse_exited.modifiers;
2886 PlatformInput::MouseExited(mouse_exited)
2887 }
2888 PlatformInput::ModifiersChanged(modifiers_changed) => {
2889 self.window.modifiers = modifiers_changed.modifiers;
2890 PlatformInput::ModifiersChanged(modifiers_changed)
2891 }
2892 PlatformInput::ScrollWheel(scroll_wheel) => {
2893 self.window.mouse_position = scroll_wheel.position;
2894 self.window.modifiers = scroll_wheel.modifiers;
2895 PlatformInput::ScrollWheel(scroll_wheel)
2896 }
2897 // Translate dragging and dropping of external files from the operating system
2898 // to internal drag and drop events.
2899 PlatformInput::FileDrop(file_drop) => match file_drop {
2900 FileDropEvent::Entered { position, paths } => {
2901 self.window.mouse_position = position;
2902 if self.active_drag.is_none() {
2903 self.active_drag = Some(AnyDrag {
2904 value: Box::new(paths.clone()),
2905 view: self.new_view(|_| paths).into(),
2906 cursor_offset: position,
2907 });
2908 }
2909 PlatformInput::MouseMove(MouseMoveEvent {
2910 position,
2911 pressed_button: Some(MouseButton::Left),
2912 modifiers: Modifiers::default(),
2913 })
2914 }
2915 FileDropEvent::Pending { position } => {
2916 self.window.mouse_position = position;
2917 PlatformInput::MouseMove(MouseMoveEvent {
2918 position,
2919 pressed_button: Some(MouseButton::Left),
2920 modifiers: Modifiers::default(),
2921 })
2922 }
2923 FileDropEvent::Submit { position } => {
2924 self.activate(true);
2925 self.window.mouse_position = position;
2926 PlatformInput::MouseUp(MouseUpEvent {
2927 button: MouseButton::Left,
2928 position,
2929 modifiers: Modifiers::default(),
2930 click_count: 1,
2931 })
2932 }
2933 FileDropEvent::Exited => {
2934 self.active_drag.take();
2935 PlatformInput::FileDrop(FileDropEvent::Exited)
2936 }
2937 },
2938 PlatformInput::KeyDown(_) | PlatformInput::KeyUp(_) => event,
2939 };
2940
2941 if let Some(any_mouse_event) = event.mouse_event() {
2942 self.dispatch_mouse_event(any_mouse_event);
2943 } else if let Some(any_key_event) = event.keyboard_event() {
2944 self.dispatch_key_event(any_key_event);
2945 }
2946
2947 DispatchEventResult {
2948 propagate: self.app.propagate_event,
2949 default_prevented: self.window.default_prevented,
2950 }
2951 }
2952
2953 fn dispatch_mouse_event(&mut self, event: &dyn Any) {
2954 let hit_test = self.window.rendered_frame.hit_test(self.mouse_position());
2955 if hit_test != self.window.mouse_hit_test {
2956 self.window.mouse_hit_test = hit_test;
2957 self.reset_cursor_style();
2958 }
2959
2960 let mut mouse_listeners = mem::take(&mut self.window.rendered_frame.mouse_listeners);
2961
2962 // Capture phase, events bubble from back to front. Handlers for this phase are used for
2963 // special purposes, such as detecting events outside of a given Bounds.
2964 for listener in &mut mouse_listeners {
2965 let listener = listener.as_mut().unwrap();
2966 listener(event, DispatchPhase::Capture, self);
2967 if !self.app.propagate_event {
2968 break;
2969 }
2970 }
2971
2972 // Bubble phase, where most normal handlers do their work.
2973 if self.app.propagate_event {
2974 for listener in mouse_listeners.iter_mut().rev() {
2975 let listener = listener.as_mut().unwrap();
2976 listener(event, DispatchPhase::Bubble, self);
2977 if !self.app.propagate_event {
2978 break;
2979 }
2980 }
2981 }
2982
2983 self.window.rendered_frame.mouse_listeners = mouse_listeners;
2984
2985 if self.has_active_drag() {
2986 if event.is::<MouseMoveEvent>() {
2987 // If this was a mouse move event, redraw the window so that the
2988 // active drag can follow the mouse cursor.
2989 self.refresh();
2990 } else if event.is::<MouseUpEvent>() {
2991 // If this was a mouse up event, cancel the active drag and redraw
2992 // the window.
2993 self.active_drag = None;
2994 self.refresh();
2995 }
2996 }
2997 }
2998
2999 fn dispatch_key_event(&mut self, event: &dyn Any) {
3000 if self.window.dirty.get() {
3001 self.draw();
3002 }
3003
3004 let node_id = self
3005 .window
3006 .focus
3007 .and_then(|focus_id| {
3008 self.window
3009 .rendered_frame
3010 .dispatch_tree
3011 .focusable_node_id(focus_id)
3012 })
3013 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3014
3015 let dispatch_path = self
3016 .window
3017 .rendered_frame
3018 .dispatch_tree
3019 .dispatch_path(node_id);
3020
3021 if let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() {
3022 let KeymatchResult { bindings, pending } = self
3023 .window
3024 .rendered_frame
3025 .dispatch_tree
3026 .dispatch_key(&key_down_event.keystroke, &dispatch_path);
3027
3028 if pending {
3029 let mut currently_pending = self.window.pending_input.take().unwrap_or_default();
3030 if currently_pending.focus.is_some() && currently_pending.focus != self.window.focus
3031 {
3032 currently_pending = PendingInput::default();
3033 }
3034 currently_pending.focus = self.window.focus;
3035 currently_pending
3036 .keystrokes
3037 .push(key_down_event.keystroke.clone());
3038 for binding in bindings {
3039 currently_pending.bindings.push(binding);
3040 }
3041
3042 currently_pending.timer = Some(self.spawn(|mut cx| async move {
3043 cx.background_executor.timer(Duration::from_secs(1)).await;
3044 cx.update(move |cx| {
3045 cx.clear_pending_keystrokes();
3046 let Some(currently_pending) = cx.window.pending_input.take() else {
3047 return;
3048 };
3049 cx.replay_pending_input(currently_pending)
3050 })
3051 .log_err();
3052 }));
3053
3054 self.window.pending_input = Some(currently_pending);
3055
3056 self.propagate_event = false;
3057 return;
3058 } else if let Some(currently_pending) = self.window.pending_input.take() {
3059 if bindings
3060 .iter()
3061 .all(|binding| !currently_pending.used_by_binding(binding))
3062 {
3063 self.replay_pending_input(currently_pending)
3064 }
3065 }
3066
3067 if !bindings.is_empty() {
3068 self.clear_pending_keystrokes();
3069 }
3070
3071 self.propagate_event = true;
3072 for binding in bindings {
3073 self.dispatch_action_on_node(node_id, binding.action.as_ref());
3074 if !self.propagate_event {
3075 self.dispatch_keystroke_observers(event, Some(binding.action));
3076 return;
3077 }
3078 }
3079 }
3080
3081 self.dispatch_key_down_up_event(event, &dispatch_path);
3082 if !self.propagate_event {
3083 return;
3084 }
3085
3086 self.dispatch_modifiers_changed_event(event, &dispatch_path);
3087 if !self.propagate_event {
3088 return;
3089 }
3090
3091 self.dispatch_keystroke_observers(event, None);
3092 }
3093
3094 fn dispatch_key_down_up_event(
3095 &mut self,
3096 event: &dyn Any,
3097 dispatch_path: &SmallVec<[DispatchNodeId; 32]>,
3098 ) {
3099 // Capture phase
3100 for node_id in dispatch_path {
3101 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3102
3103 for key_listener in node.key_listeners.clone() {
3104 key_listener(event, DispatchPhase::Capture, self);
3105 if !self.propagate_event {
3106 return;
3107 }
3108 }
3109 }
3110
3111 // Bubble phase
3112 for node_id in dispatch_path.iter().rev() {
3113 // Handle low level key events
3114 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3115 for key_listener in node.key_listeners.clone() {
3116 key_listener(event, DispatchPhase::Bubble, self);
3117 if !self.propagate_event {
3118 return;
3119 }
3120 }
3121 }
3122 }
3123
3124 fn dispatch_modifiers_changed_event(
3125 &mut self,
3126 event: &dyn Any,
3127 dispatch_path: &SmallVec<[DispatchNodeId; 32]>,
3128 ) {
3129 let Some(event) = event.downcast_ref::<ModifiersChangedEvent>() else {
3130 return;
3131 };
3132 for node_id in dispatch_path.iter().rev() {
3133 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3134 for listener in node.modifiers_changed_listeners.clone() {
3135 listener(event, self);
3136 if !self.propagate_event {
3137 return;
3138 }
3139 }
3140 }
3141 }
3142
3143 /// Determine whether a potential multi-stroke key binding is in progress on this window.
3144 pub fn has_pending_keystrokes(&self) -> bool {
3145 self.window
3146 .rendered_frame
3147 .dispatch_tree
3148 .has_pending_keystrokes()
3149 }
3150
3151 fn replay_pending_input(&mut self, currently_pending: PendingInput) {
3152 let node_id = self
3153 .window
3154 .focus
3155 .and_then(|focus_id| {
3156 self.window
3157 .rendered_frame
3158 .dispatch_tree
3159 .focusable_node_id(focus_id)
3160 })
3161 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3162
3163 if self.window.focus != currently_pending.focus {
3164 return;
3165 }
3166
3167 let input = currently_pending.input();
3168
3169 self.propagate_event = true;
3170 for binding in currently_pending.bindings {
3171 self.dispatch_action_on_node(node_id, binding.action.as_ref());
3172 if !self.propagate_event {
3173 return;
3174 }
3175 }
3176
3177 let dispatch_path = self
3178 .window
3179 .rendered_frame
3180 .dispatch_tree
3181 .dispatch_path(node_id);
3182
3183 for keystroke in currently_pending.keystrokes {
3184 let event = KeyDownEvent {
3185 keystroke,
3186 is_held: false,
3187 };
3188
3189 self.dispatch_key_down_up_event(&event, &dispatch_path);
3190 if !self.propagate_event {
3191 return;
3192 }
3193 }
3194
3195 if !input.is_empty() {
3196 if let Some(mut input_handler) = self.window.platform_window.take_input_handler() {
3197 input_handler.dispatch_input(&input, self);
3198 self.window.platform_window.set_input_handler(input_handler)
3199 }
3200 }
3201 }
3202
3203 fn dispatch_action_on_node(&mut self, node_id: DispatchNodeId, action: &dyn Action) {
3204 let dispatch_path = self
3205 .window
3206 .rendered_frame
3207 .dispatch_tree
3208 .dispatch_path(node_id);
3209
3210 // Capture phase for global actions.
3211 self.propagate_event = true;
3212 if let Some(mut global_listeners) = self
3213 .global_action_listeners
3214 .remove(&action.as_any().type_id())
3215 {
3216 for listener in &global_listeners {
3217 listener(action.as_any(), DispatchPhase::Capture, self);
3218 if !self.propagate_event {
3219 break;
3220 }
3221 }
3222
3223 global_listeners.extend(
3224 self.global_action_listeners
3225 .remove(&action.as_any().type_id())
3226 .unwrap_or_default(),
3227 );
3228
3229 self.global_action_listeners
3230 .insert(action.as_any().type_id(), global_listeners);
3231 }
3232
3233 if !self.propagate_event {
3234 return;
3235 }
3236
3237 // Capture phase for window actions.
3238 for node_id in &dispatch_path {
3239 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3240 for DispatchActionListener {
3241 action_type,
3242 listener,
3243 } in node.action_listeners.clone()
3244 {
3245 let any_action = action.as_any();
3246 if action_type == any_action.type_id() {
3247 listener(any_action, DispatchPhase::Capture, self);
3248
3249 if !self.propagate_event {
3250 return;
3251 }
3252 }
3253 }
3254 }
3255
3256 // Bubble phase for window actions.
3257 for node_id in dispatch_path.iter().rev() {
3258 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3259 for DispatchActionListener {
3260 action_type,
3261 listener,
3262 } in node.action_listeners.clone()
3263 {
3264 let any_action = action.as_any();
3265 if action_type == any_action.type_id() {
3266 self.propagate_event = false; // Actions stop propagation by default during the bubble phase
3267 listener(any_action, DispatchPhase::Bubble, self);
3268
3269 if !self.propagate_event {
3270 return;
3271 }
3272 }
3273 }
3274 }
3275
3276 // Bubble phase for global actions.
3277 if let Some(mut global_listeners) = self
3278 .global_action_listeners
3279 .remove(&action.as_any().type_id())
3280 {
3281 for listener in global_listeners.iter().rev() {
3282 self.propagate_event = false; // Actions stop propagation by default during the bubble phase
3283
3284 listener(action.as_any(), DispatchPhase::Bubble, self);
3285 if !self.propagate_event {
3286 break;
3287 }
3288 }
3289
3290 global_listeners.extend(
3291 self.global_action_listeners
3292 .remove(&action.as_any().type_id())
3293 .unwrap_or_default(),
3294 );
3295
3296 self.global_action_listeners
3297 .insert(action.as_any().type_id(), global_listeners);
3298 }
3299 }
3300
3301 /// Register the given handler to be invoked whenever the global of the given type
3302 /// is updated.
3303 pub fn observe_global<G: Global>(
3304 &mut self,
3305 f: impl Fn(&mut WindowContext<'_>) + 'static,
3306 ) -> Subscription {
3307 let window_handle = self.window.handle;
3308 let (subscription, activate) = self.global_observers.insert(
3309 TypeId::of::<G>(),
3310 Box::new(move |cx| window_handle.update(cx, |_, cx| f(cx)).is_ok()),
3311 );
3312 self.app.defer(move |_| activate());
3313 subscription
3314 }
3315
3316 /// Focus the current window and bring it to the foreground at the platform level.
3317 pub fn activate_window(&self) {
3318 self.window.platform_window.activate();
3319 }
3320
3321 /// Minimize the current window at the platform level.
3322 pub fn minimize_window(&self) {
3323 self.window.platform_window.minimize();
3324 }
3325
3326 /// Toggle full screen status on the current window at the platform level.
3327 pub fn toggle_fullscreen(&self) {
3328 self.window.platform_window.toggle_fullscreen();
3329 }
3330
3331 /// Present a platform dialog.
3332 /// The provided message will be presented, along with buttons for each answer.
3333 /// When a button is clicked, the returned Receiver will receive the index of the clicked button.
3334 pub fn prompt(
3335 &mut self,
3336 level: PromptLevel,
3337 message: &str,
3338 detail: Option<&str>,
3339 answers: &[&str],
3340 ) -> oneshot::Receiver<usize> {
3341 let prompt_builder = self.app.prompt_builder.take();
3342 let Some(prompt_builder) = prompt_builder else {
3343 unreachable!("Re-entrant window prompting is not supported by GPUI");
3344 };
3345
3346 let receiver = match &prompt_builder {
3347 PromptBuilder::Default => self
3348 .window
3349 .platform_window
3350 .prompt(level, message, detail, answers)
3351 .unwrap_or_else(|| {
3352 self.build_custom_prompt(&prompt_builder, level, message, detail, answers)
3353 }),
3354 PromptBuilder::Custom(_) => {
3355 self.build_custom_prompt(&prompt_builder, level, message, detail, answers)
3356 }
3357 };
3358
3359 self.app.prompt_builder = Some(prompt_builder);
3360
3361 receiver
3362 }
3363
3364 fn build_custom_prompt(
3365 &mut self,
3366 prompt_builder: &PromptBuilder,
3367 level: PromptLevel,
3368 message: &str,
3369 detail: Option<&str>,
3370 answers: &[&str],
3371 ) -> oneshot::Receiver<usize> {
3372 let (sender, receiver) = oneshot::channel();
3373 let handle = PromptHandle::new(sender);
3374 let handle = (prompt_builder)(level, message, detail, answers, handle, self);
3375 self.window.prompt = Some(handle);
3376 receiver
3377 }
3378
3379 /// Returns all available actions for the focused element.
3380 pub fn available_actions(&self) -> Vec<Box<dyn Action>> {
3381 let node_id = self
3382 .window
3383 .focus
3384 .and_then(|focus_id| {
3385 self.window
3386 .rendered_frame
3387 .dispatch_tree
3388 .focusable_node_id(focus_id)
3389 })
3390 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3391
3392 let mut actions = self
3393 .window
3394 .rendered_frame
3395 .dispatch_tree
3396 .available_actions(node_id);
3397 for action_type in self.global_action_listeners.keys() {
3398 if let Err(ix) = actions.binary_search_by_key(action_type, |a| a.as_any().type_id()) {
3399 let action = self.actions.build_action_type(action_type).ok();
3400 if let Some(action) = action {
3401 actions.insert(ix, action);
3402 }
3403 }
3404 }
3405 actions
3406 }
3407
3408 /// Returns key bindings that invoke the given action on the currently focused element.
3409 pub fn bindings_for_action(&self, action: &dyn Action) -> Vec<KeyBinding> {
3410 self.window
3411 .rendered_frame
3412 .dispatch_tree
3413 .bindings_for_action(
3414 action,
3415 &self.window.rendered_frame.dispatch_tree.context_stack,
3416 )
3417 }
3418
3419 /// Returns any bindings that would invoke the given action on the given focus handle if it were focused.
3420 pub fn bindings_for_action_in(
3421 &self,
3422 action: &dyn Action,
3423 focus_handle: &FocusHandle,
3424 ) -> Vec<KeyBinding> {
3425 let dispatch_tree = &self.window.rendered_frame.dispatch_tree;
3426
3427 let Some(node_id) = dispatch_tree.focusable_node_id(focus_handle.id) else {
3428 return vec![];
3429 };
3430 let context_stack: Vec<_> = dispatch_tree
3431 .dispatch_path(node_id)
3432 .into_iter()
3433 .filter_map(|node_id| dispatch_tree.node(node_id).context.clone())
3434 .collect();
3435 dispatch_tree.bindings_for_action(action, &context_stack)
3436 }
3437
3438 /// Returns a generic event listener that invokes the given listener with the view and context associated with the given view handle.
3439 pub fn listener_for<V: Render, E>(
3440 &self,
3441 view: &View<V>,
3442 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
3443 ) -> impl Fn(&E, &mut WindowContext) + 'static {
3444 let view = view.downgrade();
3445 move |e: &E, cx: &mut WindowContext| {
3446 view.update(cx, |view, cx| f(view, e, cx)).ok();
3447 }
3448 }
3449
3450 /// Returns a generic handler that invokes the given handler with the view and context associated with the given view handle.
3451 pub fn handler_for<V: Render>(
3452 &self,
3453 view: &View<V>,
3454 f: impl Fn(&mut V, &mut ViewContext<V>) + 'static,
3455 ) -> impl Fn(&mut WindowContext) {
3456 let view = view.downgrade();
3457 move |cx: &mut WindowContext| {
3458 view.update(cx, |view, cx| f(view, cx)).ok();
3459 }
3460 }
3461
3462 /// Register a callback that can interrupt the closing of the current window based the returned boolean.
3463 /// If the callback returns false, the window won't be closed.
3464 pub fn on_window_should_close(&mut self, f: impl Fn(&mut WindowContext) -> bool + 'static) {
3465 let mut this = self.to_async();
3466 self.window
3467 .platform_window
3468 .on_should_close(Box::new(move || this.update(|cx| f(cx)).unwrap_or(true)))
3469 }
3470
3471 /// Register an action listener on the window for the next frame. The type of action
3472 /// is determined by the first parameter of the given listener. When the next frame is rendered
3473 /// the listener will be cleared.
3474 ///
3475 /// This is a fairly low-level method, so prefer using action handlers on elements unless you have
3476 /// a specific need to register a global listener.
3477 pub fn on_action(
3478 &mut self,
3479 action_type: TypeId,
3480 listener: impl Fn(&dyn Any, DispatchPhase, &mut WindowContext) + 'static,
3481 ) {
3482 self.window
3483 .next_frame
3484 .dispatch_tree
3485 .on_action(action_type, Rc::new(listener));
3486 }
3487}
3488
3489#[cfg(target_os = "windows")]
3490impl WindowContext<'_> {
3491 /// Returns the raw HWND handle for the window.
3492 pub fn get_raw_handle(&self) -> windows::Win32::Foundation::HWND {
3493 self.window.platform_window.get_raw_handle()
3494 }
3495}
3496
3497impl Context for WindowContext<'_> {
3498 type Result<T> = T;
3499
3500 fn new_model<T>(&mut self, build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T) -> Model<T>
3501 where
3502 T: 'static,
3503 {
3504 let slot = self.app.entities.reserve();
3505 let model = build_model(&mut ModelContext::new(&mut *self.app, slot.downgrade()));
3506 self.entities.insert(slot, model)
3507 }
3508
3509 fn reserve_model<T: 'static>(&mut self) -> Self::Result<crate::Reservation<T>> {
3510 self.app.reserve_model()
3511 }
3512
3513 fn insert_model<T: 'static>(
3514 &mut self,
3515 reservation: crate::Reservation<T>,
3516 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
3517 ) -> Self::Result<Model<T>> {
3518 self.app.insert_model(reservation, build_model)
3519 }
3520
3521 fn update_model<T: 'static, R>(
3522 &mut self,
3523 model: &Model<T>,
3524 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
3525 ) -> R {
3526 let mut entity = self.entities.lease(model);
3527 let result = update(
3528 &mut *entity,
3529 &mut ModelContext::new(&mut *self.app, model.downgrade()),
3530 );
3531 self.entities.end_lease(entity);
3532 result
3533 }
3534
3535 fn read_model<T, R>(
3536 &self,
3537 handle: &Model<T>,
3538 read: impl FnOnce(&T, &AppContext) -> R,
3539 ) -> Self::Result<R>
3540 where
3541 T: 'static,
3542 {
3543 let entity = self.entities.read(handle);
3544 read(entity, &*self.app)
3545 }
3546
3547 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
3548 where
3549 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
3550 {
3551 if window == self.window.handle {
3552 let root_view = self.window.root_view.clone().unwrap();
3553 Ok(update(root_view, self))
3554 } else {
3555 window.update(self.app, update)
3556 }
3557 }
3558
3559 fn read_window<T, R>(
3560 &self,
3561 window: &WindowHandle<T>,
3562 read: impl FnOnce(View<T>, &AppContext) -> R,
3563 ) -> Result<R>
3564 where
3565 T: 'static,
3566 {
3567 if window.any_handle == self.window.handle {
3568 let root_view = self
3569 .window
3570 .root_view
3571 .clone()
3572 .unwrap()
3573 .downcast::<T>()
3574 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
3575 Ok(read(root_view, self))
3576 } else {
3577 self.app.read_window(window, read)
3578 }
3579 }
3580}
3581
3582impl VisualContext for WindowContext<'_> {
3583 fn new_view<V>(
3584 &mut self,
3585 build_view_state: impl FnOnce(&mut ViewContext<'_, V>) -> V,
3586 ) -> Self::Result<View<V>>
3587 where
3588 V: 'static + Render,
3589 {
3590 let slot = self.app.entities.reserve();
3591 let view = View {
3592 model: slot.clone(),
3593 };
3594 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
3595 let entity = build_view_state(&mut cx);
3596 cx.entities.insert(slot, entity);
3597
3598 // Non-generic part to avoid leaking SubscriberSet to invokers of `new_view`.
3599 fn notify_observers(cx: &mut WindowContext, tid: TypeId, view: AnyView) {
3600 cx.new_view_observers.clone().retain(&tid, |observer| {
3601 let any_view = view.clone();
3602 (observer)(any_view, cx);
3603 true
3604 });
3605 }
3606 notify_observers(self, TypeId::of::<V>(), AnyView::from(view.clone()));
3607
3608 view
3609 }
3610
3611 /// Updates the given view. Prefer calling [`View::update`] instead, which calls this method.
3612 fn update_view<T: 'static, R>(
3613 &mut self,
3614 view: &View<T>,
3615 update: impl FnOnce(&mut T, &mut ViewContext<'_, T>) -> R,
3616 ) -> Self::Result<R> {
3617 let mut lease = self.app.entities.lease(&view.model);
3618 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, view);
3619 let result = update(&mut *lease, &mut cx);
3620 cx.app.entities.end_lease(lease);
3621 result
3622 }
3623
3624 fn replace_root_view<V>(
3625 &mut self,
3626 build_view: impl FnOnce(&mut ViewContext<'_, V>) -> V,
3627 ) -> Self::Result<View<V>>
3628 where
3629 V: 'static + Render,
3630 {
3631 let view = self.new_view(build_view);
3632 self.window.root_view = Some(view.clone().into());
3633 self.refresh();
3634 view
3635 }
3636
3637 fn focus_view<V: crate::FocusableView>(&mut self, view: &View<V>) -> Self::Result<()> {
3638 self.update_view(view, |view, cx| {
3639 view.focus_handle(cx).clone().focus(cx);
3640 })
3641 }
3642
3643 fn dismiss_view<V>(&mut self, view: &View<V>) -> Self::Result<()>
3644 where
3645 V: ManagedView,
3646 {
3647 self.update_view(view, |_, cx| cx.emit(DismissEvent))
3648 }
3649}
3650
3651impl<'a> std::ops::Deref for WindowContext<'a> {
3652 type Target = AppContext;
3653
3654 fn deref(&self) -> &Self::Target {
3655 self.app
3656 }
3657}
3658
3659impl<'a> std::ops::DerefMut for WindowContext<'a> {
3660 fn deref_mut(&mut self) -> &mut Self::Target {
3661 self.app
3662 }
3663}
3664
3665impl<'a> Borrow<AppContext> for WindowContext<'a> {
3666 fn borrow(&self) -> &AppContext {
3667 self.app
3668 }
3669}
3670
3671impl<'a> BorrowMut<AppContext> for WindowContext<'a> {
3672 fn borrow_mut(&mut self) -> &mut AppContext {
3673 self.app
3674 }
3675}
3676
3677/// This trait contains functionality that is shared across [`ViewContext`] and [`WindowContext`]
3678pub trait BorrowWindow: BorrowMut<Window> + BorrowMut<AppContext> {
3679 #[doc(hidden)]
3680 fn app_mut(&mut self) -> &mut AppContext {
3681 self.borrow_mut()
3682 }
3683
3684 #[doc(hidden)]
3685 fn app(&self) -> &AppContext {
3686 self.borrow()
3687 }
3688
3689 #[doc(hidden)]
3690 fn window(&self) -> &Window {
3691 self.borrow()
3692 }
3693
3694 #[doc(hidden)]
3695 fn window_mut(&mut self) -> &mut Window {
3696 self.borrow_mut()
3697 }
3698}
3699
3700impl Borrow<Window> for WindowContext<'_> {
3701 fn borrow(&self) -> &Window {
3702 self.window
3703 }
3704}
3705
3706impl BorrowMut<Window> for WindowContext<'_> {
3707 fn borrow_mut(&mut self) -> &mut Window {
3708 self.window
3709 }
3710}
3711
3712impl<T> BorrowWindow for T where T: BorrowMut<AppContext> + BorrowMut<Window> {}
3713
3714/// Provides access to application state that is specialized for a particular [`View`].
3715/// Allows you to interact with focus, emit events, etc.
3716/// ViewContext also derefs to [`WindowContext`], giving you access to all of its methods as well.
3717/// When you call [`View::update`], you're passed a `&mut V` and an `&mut ViewContext<V>`.
3718pub struct ViewContext<'a, V> {
3719 window_cx: WindowContext<'a>,
3720 view: &'a View<V>,
3721}
3722
3723impl<V> Borrow<AppContext> for ViewContext<'_, V> {
3724 fn borrow(&self) -> &AppContext {
3725 &*self.window_cx.app
3726 }
3727}
3728
3729impl<V> BorrowMut<AppContext> for ViewContext<'_, V> {
3730 fn borrow_mut(&mut self) -> &mut AppContext {
3731 &mut *self.window_cx.app
3732 }
3733}
3734
3735impl<V> Borrow<Window> for ViewContext<'_, V> {
3736 fn borrow(&self) -> &Window {
3737 &*self.window_cx.window
3738 }
3739}
3740
3741impl<V> BorrowMut<Window> for ViewContext<'_, V> {
3742 fn borrow_mut(&mut self) -> &mut Window {
3743 &mut *self.window_cx.window
3744 }
3745}
3746
3747impl<'a, V: 'static> ViewContext<'a, V> {
3748 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window, view: &'a View<V>) -> Self {
3749 Self {
3750 window_cx: WindowContext::new(app, window),
3751 view,
3752 }
3753 }
3754
3755 /// Get the entity_id of this view.
3756 pub fn entity_id(&self) -> EntityId {
3757 self.view.entity_id()
3758 }
3759
3760 /// Get the view pointer underlying this context.
3761 pub fn view(&self) -> &View<V> {
3762 self.view
3763 }
3764
3765 /// Get the model underlying this view.
3766 pub fn model(&self) -> &Model<V> {
3767 &self.view.model
3768 }
3769
3770 /// Access the underlying window context.
3771 pub fn window_context(&mut self) -> &mut WindowContext<'a> {
3772 &mut self.window_cx
3773 }
3774
3775 /// Sets a given callback to be run on the next frame.
3776 pub fn on_next_frame(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static)
3777 where
3778 V: 'static,
3779 {
3780 let view = self.view().clone();
3781 self.window_cx.on_next_frame(move |cx| view.update(cx, f));
3782 }
3783
3784 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
3785 /// that are currently on the stack to be returned to the app.
3786 pub fn defer(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static) {
3787 let view = self.view().downgrade();
3788 self.window_cx.defer(move |cx| {
3789 view.update(cx, f).ok();
3790 });
3791 }
3792
3793 /// Observe another model or view for changes to its state, as tracked by [`ModelContext::notify`].
3794 pub fn observe<V2, E>(
3795 &mut self,
3796 entity: &E,
3797 mut on_notify: impl FnMut(&mut V, E, &mut ViewContext<'_, V>) + 'static,
3798 ) -> Subscription
3799 where
3800 V2: 'static,
3801 V: 'static,
3802 E: Entity<V2>,
3803 {
3804 let view = self.view().downgrade();
3805 let entity_id = entity.entity_id();
3806 let entity = entity.downgrade();
3807 let window_handle = self.window.handle;
3808 self.app.new_observer(
3809 entity_id,
3810 Box::new(move |cx| {
3811 window_handle
3812 .update(cx, |_, cx| {
3813 if let Some(handle) = E::upgrade_from(&entity) {
3814 view.update(cx, |this, cx| on_notify(this, handle, cx))
3815 .is_ok()
3816 } else {
3817 false
3818 }
3819 })
3820 .unwrap_or(false)
3821 }),
3822 )
3823 }
3824
3825 /// Subscribe to events emitted by another model or view.
3826 /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
3827 /// The callback will be invoked with a reference to the current view, a handle to the emitting entity (either a [`View`] or [`Model`]), the event, and a view context for the current view.
3828 pub fn subscribe<V2, E, Evt>(
3829 &mut self,
3830 entity: &E,
3831 mut on_event: impl FnMut(&mut V, E, &Evt, &mut ViewContext<'_, V>) + 'static,
3832 ) -> Subscription
3833 where
3834 V2: EventEmitter<Evt>,
3835 E: Entity<V2>,
3836 Evt: 'static,
3837 {
3838 let view = self.view().downgrade();
3839 let entity_id = entity.entity_id();
3840 let handle = entity.downgrade();
3841 let window_handle = self.window.handle;
3842 self.app.new_subscription(
3843 entity_id,
3844 (
3845 TypeId::of::<Evt>(),
3846 Box::new(move |event, cx| {
3847 window_handle
3848 .update(cx, |_, cx| {
3849 if let Some(handle) = E::upgrade_from(&handle) {
3850 let event = event.downcast_ref().expect("invalid event type");
3851 view.update(cx, |this, cx| on_event(this, handle, event, cx))
3852 .is_ok()
3853 } else {
3854 false
3855 }
3856 })
3857 .unwrap_or(false)
3858 }),
3859 ),
3860 )
3861 }
3862
3863 /// Register a callback to be invoked when the view is released.
3864 ///
3865 /// The callback receives a handle to the view's window. This handle may be
3866 /// invalid, if the window was closed before the view was released.
3867 pub fn on_release(
3868 &mut self,
3869 on_release: impl FnOnce(&mut V, AnyWindowHandle, &mut AppContext) + 'static,
3870 ) -> Subscription {
3871 let window_handle = self.window.handle;
3872 let (subscription, activate) = self.app.release_listeners.insert(
3873 self.view.model.entity_id,
3874 Box::new(move |this, cx| {
3875 let this = this.downcast_mut().expect("invalid entity type");
3876 on_release(this, window_handle, cx)
3877 }),
3878 );
3879 activate();
3880 subscription
3881 }
3882
3883 /// Register a callback to be invoked when the given Model or View is released.
3884 pub fn observe_release<V2, E>(
3885 &mut self,
3886 entity: &E,
3887 mut on_release: impl FnMut(&mut V, &mut V2, &mut ViewContext<'_, V>) + 'static,
3888 ) -> Subscription
3889 where
3890 V: 'static,
3891 V2: 'static,
3892 E: Entity<V2>,
3893 {
3894 let view = self.view().downgrade();
3895 let entity_id = entity.entity_id();
3896 let window_handle = self.window.handle;
3897 let (subscription, activate) = self.app.release_listeners.insert(
3898 entity_id,
3899 Box::new(move |entity, cx| {
3900 let entity = entity.downcast_mut().expect("invalid entity type");
3901 let _ = window_handle.update(cx, |_, cx| {
3902 view.update(cx, |this, cx| on_release(this, entity, cx))
3903 });
3904 }),
3905 );
3906 activate();
3907 subscription
3908 }
3909
3910 /// Indicate that this view has changed, which will invoke any observers and also mark the window as dirty.
3911 /// If this view or any of its ancestors are *cached*, notifying it will cause it or its ancestors to be redrawn.
3912 pub fn notify(&mut self) {
3913 self.window_cx.notify(self.view.entity_id());
3914 }
3915
3916 /// Register a callback to be invoked when the window is resized.
3917 pub fn observe_window_bounds(
3918 &mut self,
3919 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
3920 ) -> Subscription {
3921 let view = self.view.downgrade();
3922 let (subscription, activate) = self.window.bounds_observers.insert(
3923 (),
3924 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
3925 );
3926 activate();
3927 subscription
3928 }
3929
3930 /// Register a callback to be invoked when the window is activated or deactivated.
3931 pub fn observe_window_activation(
3932 &mut self,
3933 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
3934 ) -> Subscription {
3935 let view = self.view.downgrade();
3936 let (subscription, activate) = self.window.activation_observers.insert(
3937 (),
3938 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
3939 );
3940 activate();
3941 subscription
3942 }
3943
3944 /// Registers a callback to be invoked when the window appearance changes.
3945 pub fn observe_window_appearance(
3946 &mut self,
3947 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
3948 ) -> Subscription {
3949 let view = self.view.downgrade();
3950 let (subscription, activate) = self.window.appearance_observers.insert(
3951 (),
3952 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
3953 );
3954 activate();
3955 subscription
3956 }
3957
3958 /// Register a listener to be called when the given focus handle receives focus.
3959 /// Returns a subscription and persists until the subscription is dropped.
3960 pub fn on_focus(
3961 &mut self,
3962 handle: &FocusHandle,
3963 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
3964 ) -> Subscription {
3965 let view = self.view.downgrade();
3966 let focus_id = handle.id;
3967 let (subscription, activate) =
3968 self.window.new_focus_listener(Box::new(move |event, cx| {
3969 view.update(cx, |view, cx| {
3970 if event.previous_focus_path.last() != Some(&focus_id)
3971 && event.current_focus_path.last() == Some(&focus_id)
3972 {
3973 listener(view, cx)
3974 }
3975 })
3976 .is_ok()
3977 }));
3978 self.app.defer(|_| activate());
3979 subscription
3980 }
3981
3982 /// Register a listener to be called when the given focus handle or one of its descendants receives focus.
3983 /// Returns a subscription and persists until the subscription is dropped.
3984 pub fn on_focus_in(
3985 &mut self,
3986 handle: &FocusHandle,
3987 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
3988 ) -> Subscription {
3989 let view = self.view.downgrade();
3990 let focus_id = handle.id;
3991 let (subscription, activate) =
3992 self.window.new_focus_listener(Box::new(move |event, cx| {
3993 view.update(cx, |view, cx| {
3994 if !event.previous_focus_path.contains(&focus_id)
3995 && event.current_focus_path.contains(&focus_id)
3996 {
3997 listener(view, cx)
3998 }
3999 })
4000 .is_ok()
4001 }));
4002 self.app.defer(move |_| activate());
4003 subscription
4004 }
4005
4006 /// Register a listener to be called when the given focus handle loses focus.
4007 /// Returns a subscription and persists until the subscription is dropped.
4008 pub fn on_blur(
4009 &mut self,
4010 handle: &FocusHandle,
4011 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4012 ) -> Subscription {
4013 let view = self.view.downgrade();
4014 let focus_id = handle.id;
4015 let (subscription, activate) =
4016 self.window.new_focus_listener(Box::new(move |event, cx| {
4017 view.update(cx, |view, cx| {
4018 if event.previous_focus_path.last() == Some(&focus_id)
4019 && event.current_focus_path.last() != Some(&focus_id)
4020 {
4021 listener(view, cx)
4022 }
4023 })
4024 .is_ok()
4025 }));
4026 self.app.defer(move |_| activate());
4027 subscription
4028 }
4029
4030 /// Register a listener to be called when nothing in the window has focus.
4031 /// This typically happens when the node that was focused is removed from the tree,
4032 /// and this callback lets you chose a default place to restore the users focus.
4033 /// Returns a subscription and persists until the subscription is dropped.
4034 pub fn on_focus_lost(
4035 &mut self,
4036 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4037 ) -> Subscription {
4038 let view = self.view.downgrade();
4039 let (subscription, activate) = self.window.focus_lost_listeners.insert(
4040 (),
4041 Box::new(move |cx| view.update(cx, |view, cx| listener(view, cx)).is_ok()),
4042 );
4043 activate();
4044 subscription
4045 }
4046
4047 /// Register a listener to be called when the given focus handle or one of its descendants loses focus.
4048 /// Returns a subscription and persists until the subscription is dropped.
4049 pub fn on_focus_out(
4050 &mut self,
4051 handle: &FocusHandle,
4052 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4053 ) -> Subscription {
4054 let view = self.view.downgrade();
4055 let focus_id = handle.id;
4056 let (subscription, activate) =
4057 self.window.new_focus_listener(Box::new(move |event, cx| {
4058 view.update(cx, |view, cx| {
4059 if event.previous_focus_path.contains(&focus_id)
4060 && !event.current_focus_path.contains(&focus_id)
4061 {
4062 listener(view, cx)
4063 }
4064 })
4065 .is_ok()
4066 }));
4067 self.app.defer(move |_| activate());
4068 subscription
4069 }
4070
4071 /// Schedule a future to be run asynchronously.
4072 /// The given callback is invoked with a [`WeakView<V>`] to avoid leaking the view for a long-running process.
4073 /// It's also given an [`AsyncWindowContext`], which can be used to access the state of the view across await points.
4074 /// The returned future will be polled on the main thread.
4075 pub fn spawn<Fut, R>(
4076 &mut self,
4077 f: impl FnOnce(WeakView<V>, AsyncWindowContext) -> Fut,
4078 ) -> Task<R>
4079 where
4080 R: 'static,
4081 Fut: Future<Output = R> + 'static,
4082 {
4083 let view = self.view().downgrade();
4084 self.window_cx.spawn(|cx| f(view, cx))
4085 }
4086
4087 /// Register a callback to be invoked when the given global state changes.
4088 pub fn observe_global<G: Global>(
4089 &mut self,
4090 mut f: impl FnMut(&mut V, &mut ViewContext<'_, V>) + 'static,
4091 ) -> Subscription {
4092 let window_handle = self.window.handle;
4093 let view = self.view().downgrade();
4094 let (subscription, activate) = self.global_observers.insert(
4095 TypeId::of::<G>(),
4096 Box::new(move |cx| {
4097 window_handle
4098 .update(cx, |_, cx| view.update(cx, |view, cx| f(view, cx)).is_ok())
4099 .unwrap_or(false)
4100 }),
4101 );
4102 self.app.defer(move |_| activate());
4103 subscription
4104 }
4105
4106 /// Register a callback to be invoked when the given Action type is dispatched to the window.
4107 pub fn on_action(
4108 &mut self,
4109 action_type: TypeId,
4110 listener: impl Fn(&mut V, &dyn Any, DispatchPhase, &mut ViewContext<V>) + 'static,
4111 ) {
4112 let handle = self.view().clone();
4113 self.window_cx
4114 .on_action(action_type, move |action, phase, cx| {
4115 handle.update(cx, |view, cx| {
4116 listener(view, action, phase, cx);
4117 })
4118 });
4119 }
4120
4121 /// Emit an event to be handled any other views that have subscribed via [ViewContext::subscribe].
4122 pub fn emit<Evt>(&mut self, event: Evt)
4123 where
4124 Evt: 'static,
4125 V: EventEmitter<Evt>,
4126 {
4127 let emitter = self.view.model.entity_id;
4128 self.app.push_effect(Effect::Emit {
4129 emitter,
4130 event_type: TypeId::of::<Evt>(),
4131 event: Box::new(event),
4132 });
4133 }
4134
4135 /// Move focus to the current view, assuming it implements [`FocusableView`].
4136 pub fn focus_self(&mut self)
4137 where
4138 V: FocusableView,
4139 {
4140 self.defer(|view, cx| view.focus_handle(cx).focus(cx))
4141 }
4142
4143 /// Convenience method for accessing view state in an event callback.
4144 ///
4145 /// Many GPUI callbacks take the form of `Fn(&E, &mut WindowContext)`,
4146 /// but it's often useful to be able to access view state in these
4147 /// callbacks. This method provides a convenient way to do so.
4148 pub fn listener<E>(
4149 &self,
4150 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
4151 ) -> impl Fn(&E, &mut WindowContext) + 'static {
4152 let view = self.view().downgrade();
4153 move |e: &E, cx: &mut WindowContext| {
4154 view.update(cx, |view, cx| f(view, e, cx)).ok();
4155 }
4156 }
4157}
4158
4159impl<V> Context for ViewContext<'_, V> {
4160 type Result<U> = U;
4161
4162 fn new_model<T: 'static>(
4163 &mut self,
4164 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
4165 ) -> Model<T> {
4166 self.window_cx.new_model(build_model)
4167 }
4168
4169 fn reserve_model<T: 'static>(&mut self) -> Self::Result<crate::Reservation<T>> {
4170 self.window_cx.reserve_model()
4171 }
4172
4173 fn insert_model<T: 'static>(
4174 &mut self,
4175 reservation: crate::Reservation<T>,
4176 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
4177 ) -> Self::Result<Model<T>> {
4178 self.window_cx.insert_model(reservation, build_model)
4179 }
4180
4181 fn update_model<T: 'static, R>(
4182 &mut self,
4183 model: &Model<T>,
4184 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
4185 ) -> R {
4186 self.window_cx.update_model(model, update)
4187 }
4188
4189 fn read_model<T, R>(
4190 &self,
4191 handle: &Model<T>,
4192 read: impl FnOnce(&T, &AppContext) -> R,
4193 ) -> Self::Result<R>
4194 where
4195 T: 'static,
4196 {
4197 self.window_cx.read_model(handle, read)
4198 }
4199
4200 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
4201 where
4202 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
4203 {
4204 self.window_cx.update_window(window, update)
4205 }
4206
4207 fn read_window<T, R>(
4208 &self,
4209 window: &WindowHandle<T>,
4210 read: impl FnOnce(View<T>, &AppContext) -> R,
4211 ) -> Result<R>
4212 where
4213 T: 'static,
4214 {
4215 self.window_cx.read_window(window, read)
4216 }
4217}
4218
4219impl<V: 'static> VisualContext for ViewContext<'_, V> {
4220 fn new_view<W: Render + 'static>(
4221 &mut self,
4222 build_view_state: impl FnOnce(&mut ViewContext<'_, W>) -> W,
4223 ) -> Self::Result<View<W>> {
4224 self.window_cx.new_view(build_view_state)
4225 }
4226
4227 fn update_view<V2: 'static, R>(
4228 &mut self,
4229 view: &View<V2>,
4230 update: impl FnOnce(&mut V2, &mut ViewContext<'_, V2>) -> R,
4231 ) -> Self::Result<R> {
4232 self.window_cx.update_view(view, update)
4233 }
4234
4235 fn replace_root_view<W>(
4236 &mut self,
4237 build_view: impl FnOnce(&mut ViewContext<'_, W>) -> W,
4238 ) -> Self::Result<View<W>>
4239 where
4240 W: 'static + Render,
4241 {
4242 self.window_cx.replace_root_view(build_view)
4243 }
4244
4245 fn focus_view<W: FocusableView>(&mut self, view: &View<W>) -> Self::Result<()> {
4246 self.window_cx.focus_view(view)
4247 }
4248
4249 fn dismiss_view<W: ManagedView>(&mut self, view: &View<W>) -> Self::Result<()> {
4250 self.window_cx.dismiss_view(view)
4251 }
4252}
4253
4254impl<'a, V> std::ops::Deref for ViewContext<'a, V> {
4255 type Target = WindowContext<'a>;
4256
4257 fn deref(&self) -> &Self::Target {
4258 &self.window_cx
4259 }
4260}
4261
4262impl<'a, V> std::ops::DerefMut for ViewContext<'a, V> {
4263 fn deref_mut(&mut self) -> &mut Self::Target {
4264 &mut self.window_cx
4265 }
4266}
4267
4268// #[derive(Clone, Copy, Eq, PartialEq, Hash)]
4269slotmap::new_key_type! {
4270 /// A unique identifier for a window.
4271 pub struct WindowId;
4272}
4273
4274impl WindowId {
4275 /// Converts this window ID to a `u64`.
4276 pub fn as_u64(&self) -> u64 {
4277 self.0.as_ffi()
4278 }
4279}
4280
4281/// A handle to a window with a specific root view type.
4282/// Note that this does not keep the window alive on its own.
4283#[derive(Deref, DerefMut)]
4284pub struct WindowHandle<V> {
4285 #[deref]
4286 #[deref_mut]
4287 pub(crate) any_handle: AnyWindowHandle,
4288 state_type: PhantomData<V>,
4289}
4290
4291impl<V: 'static + Render> WindowHandle<V> {
4292 /// Creates a new handle from a window ID.
4293 /// This does not check if the root type of the window is `V`.
4294 pub fn new(id: WindowId) -> Self {
4295 WindowHandle {
4296 any_handle: AnyWindowHandle {
4297 id,
4298 state_type: TypeId::of::<V>(),
4299 },
4300 state_type: PhantomData,
4301 }
4302 }
4303
4304 /// Get the root view out of this window.
4305 ///
4306 /// This will fail if the window is closed or if the root view's type does not match `V`.
4307 pub fn root<C>(&self, cx: &mut C) -> Result<View<V>>
4308 where
4309 C: Context,
4310 {
4311 Flatten::flatten(cx.update_window(self.any_handle, |root_view, _| {
4312 root_view
4313 .downcast::<V>()
4314 .map_err(|_| anyhow!("the type of the window's root view has changed"))
4315 }))
4316 }
4317
4318 /// Updates the root view of this window.
4319 ///
4320 /// This will fail if the window has been closed or if the root view's type does not match
4321 pub fn update<C, R>(
4322 &self,
4323 cx: &mut C,
4324 update: impl FnOnce(&mut V, &mut ViewContext<'_, V>) -> R,
4325 ) -> Result<R>
4326 where
4327 C: Context,
4328 {
4329 cx.update_window(self.any_handle, |root_view, cx| {
4330 let view = root_view
4331 .downcast::<V>()
4332 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
4333 Ok(cx.update_view(&view, update))
4334 })?
4335 }
4336
4337 /// Read the root view out of this window.
4338 ///
4339 /// This will fail if the window is closed or if the root view's type does not match `V`.
4340 pub fn read<'a>(&self, cx: &'a AppContext) -> Result<&'a V> {
4341 let x = cx
4342 .windows
4343 .get(self.id)
4344 .and_then(|window| {
4345 window
4346 .as_ref()
4347 .and_then(|window| window.root_view.clone())
4348 .map(|root_view| root_view.downcast::<V>())
4349 })
4350 .ok_or_else(|| anyhow!("window not found"))?
4351 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
4352
4353 Ok(x.read(cx))
4354 }
4355
4356 /// Read the root view out of this window, with a callback
4357 ///
4358 /// This will fail if the window is closed or if the root view's type does not match `V`.
4359 pub fn read_with<C, R>(&self, cx: &C, read_with: impl FnOnce(&V, &AppContext) -> R) -> Result<R>
4360 where
4361 C: Context,
4362 {
4363 cx.read_window(self, |root_view, cx| read_with(root_view.read(cx), cx))
4364 }
4365
4366 /// Read the root view pointer off of this window.
4367 ///
4368 /// This will fail if the window is closed or if the root view's type does not match `V`.
4369 pub fn root_view<C>(&self, cx: &C) -> Result<View<V>>
4370 where
4371 C: Context,
4372 {
4373 cx.read_window(self, |root_view, _cx| root_view.clone())
4374 }
4375
4376 /// Check if this window is 'active'.
4377 ///
4378 /// Will return `None` if the window is closed or currently
4379 /// borrowed.
4380 pub fn is_active(&self, cx: &mut AppContext) -> Option<bool> {
4381 cx.update_window(self.any_handle, |_, cx| cx.is_window_active())
4382 .ok()
4383 }
4384}
4385
4386impl<V> Copy for WindowHandle<V> {}
4387
4388impl<V> Clone for WindowHandle<V> {
4389 fn clone(&self) -> Self {
4390 *self
4391 }
4392}
4393
4394impl<V> PartialEq for WindowHandle<V> {
4395 fn eq(&self, other: &Self) -> bool {
4396 self.any_handle == other.any_handle
4397 }
4398}
4399
4400impl<V> Eq for WindowHandle<V> {}
4401
4402impl<V> Hash for WindowHandle<V> {
4403 fn hash<H: Hasher>(&self, state: &mut H) {
4404 self.any_handle.hash(state);
4405 }
4406}
4407
4408impl<V: 'static> From<WindowHandle<V>> for AnyWindowHandle {
4409 fn from(val: WindowHandle<V>) -> Self {
4410 val.any_handle
4411 }
4412}
4413
4414/// A handle to a window with any root view type, which can be downcast to a window with a specific root view type.
4415#[derive(Copy, Clone, PartialEq, Eq, Hash)]
4416pub struct AnyWindowHandle {
4417 pub(crate) id: WindowId,
4418 state_type: TypeId,
4419}
4420
4421impl AnyWindowHandle {
4422 /// Get the ID of this window.
4423 pub fn window_id(&self) -> WindowId {
4424 self.id
4425 }
4426
4427 /// Attempt to convert this handle to a window handle with a specific root view type.
4428 /// If the types do not match, this will return `None`.
4429 pub fn downcast<T: 'static>(&self) -> Option<WindowHandle<T>> {
4430 if TypeId::of::<T>() == self.state_type {
4431 Some(WindowHandle {
4432 any_handle: *self,
4433 state_type: PhantomData,
4434 })
4435 } else {
4436 None
4437 }
4438 }
4439
4440 /// Updates the state of the root view of this window.
4441 ///
4442 /// This will fail if the window has been closed.
4443 pub fn update<C, R>(
4444 self,
4445 cx: &mut C,
4446 update: impl FnOnce(AnyView, &mut WindowContext<'_>) -> R,
4447 ) -> Result<R>
4448 where
4449 C: Context,
4450 {
4451 cx.update_window(self, update)
4452 }
4453
4454 /// Read the state of the root view of this window.
4455 ///
4456 /// This will fail if the window has been closed.
4457 pub fn read<T, C, R>(self, cx: &C, read: impl FnOnce(View<T>, &AppContext) -> R) -> Result<R>
4458 where
4459 C: Context,
4460 T: 'static,
4461 {
4462 let view = self
4463 .downcast::<T>()
4464 .context("the type of the window's root view has changed")?;
4465
4466 cx.read_window(&view, read)
4467 }
4468}
4469
4470/// An identifier for an [`Element`](crate::Element).
4471///
4472/// Can be constructed with a string, a number, or both, as well
4473/// as other internal representations.
4474#[derive(Clone, Debug, Eq, PartialEq, Hash)]
4475pub enum ElementId {
4476 /// The ID of a View element
4477 View(EntityId),
4478 /// An integer ID.
4479 Integer(usize),
4480 /// A string based ID.
4481 Name(SharedString),
4482 /// An ID that's equated with a focus handle.
4483 FocusHandle(FocusId),
4484 /// A combination of a name and an integer.
4485 NamedInteger(SharedString, usize),
4486}
4487
4488impl Display for ElementId {
4489 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
4490 match self {
4491 ElementId::View(entity_id) => write!(f, "view-{}", entity_id)?,
4492 ElementId::Integer(ix) => write!(f, "{}", ix)?,
4493 ElementId::Name(name) => write!(f, "{}", name)?,
4494 ElementId::FocusHandle(_) => write!(f, "FocusHandle")?,
4495 ElementId::NamedInteger(s, i) => write!(f, "{}-{}", s, i)?,
4496 }
4497
4498 Ok(())
4499 }
4500}
4501
4502impl TryInto<SharedString> for ElementId {
4503 type Error = anyhow::Error;
4504
4505 fn try_into(self) -> anyhow::Result<SharedString> {
4506 if let ElementId::Name(name) = self {
4507 Ok(name)
4508 } else {
4509 Err(anyhow!("element id is not string"))
4510 }
4511 }
4512}
4513
4514impl From<usize> for ElementId {
4515 fn from(id: usize) -> Self {
4516 ElementId::Integer(id)
4517 }
4518}
4519
4520impl From<i32> for ElementId {
4521 fn from(id: i32) -> Self {
4522 Self::Integer(id as usize)
4523 }
4524}
4525
4526impl From<SharedString> for ElementId {
4527 fn from(name: SharedString) -> Self {
4528 ElementId::Name(name)
4529 }
4530}
4531
4532impl From<&'static str> for ElementId {
4533 fn from(name: &'static str) -> Self {
4534 ElementId::Name(name.into())
4535 }
4536}
4537
4538impl<'a> From<&'a FocusHandle> for ElementId {
4539 fn from(handle: &'a FocusHandle) -> Self {
4540 ElementId::FocusHandle(handle.id)
4541 }
4542}
4543
4544impl From<(&'static str, EntityId)> for ElementId {
4545 fn from((name, id): (&'static str, EntityId)) -> Self {
4546 ElementId::NamedInteger(name.into(), id.as_u64() as usize)
4547 }
4548}
4549
4550impl From<(&'static str, usize)> for ElementId {
4551 fn from((name, id): (&'static str, usize)) -> Self {
4552 ElementId::NamedInteger(name.into(), id)
4553 }
4554}
4555
4556impl From<(&'static str, u64)> for ElementId {
4557 fn from((name, id): (&'static str, u64)) -> Self {
4558 ElementId::NamedInteger(name.into(), id as usize)
4559 }
4560}
4561
4562/// A rectangle to be rendered in the window at the given position and size.
4563/// Passed as an argument [`WindowContext::paint_quad`].
4564#[derive(Clone)]
4565pub struct PaintQuad {
4566 /// The bounds of the quad within the window.
4567 pub bounds: Bounds<Pixels>,
4568 /// The radii of the quad's corners.
4569 pub corner_radii: Corners<Pixels>,
4570 /// The background color of the quad.
4571 pub background: Hsla,
4572 /// The widths of the quad's borders.
4573 pub border_widths: Edges<Pixels>,
4574 /// The color of the quad's borders.
4575 pub border_color: Hsla,
4576}
4577
4578impl PaintQuad {
4579 /// Sets the corner radii of the quad.
4580 pub fn corner_radii(self, corner_radii: impl Into<Corners<Pixels>>) -> Self {
4581 PaintQuad {
4582 corner_radii: corner_radii.into(),
4583 ..self
4584 }
4585 }
4586
4587 /// Sets the border widths of the quad.
4588 pub fn border_widths(self, border_widths: impl Into<Edges<Pixels>>) -> Self {
4589 PaintQuad {
4590 border_widths: border_widths.into(),
4591 ..self
4592 }
4593 }
4594
4595 /// Sets the border color of the quad.
4596 pub fn border_color(self, border_color: impl Into<Hsla>) -> Self {
4597 PaintQuad {
4598 border_color: border_color.into(),
4599 ..self
4600 }
4601 }
4602
4603 /// Sets the background color of the quad.
4604 pub fn background(self, background: impl Into<Hsla>) -> Self {
4605 PaintQuad {
4606 background: background.into(),
4607 ..self
4608 }
4609 }
4610}
4611
4612/// Creates a quad with the given parameters.
4613pub fn quad(
4614 bounds: Bounds<Pixels>,
4615 corner_radii: impl Into<Corners<Pixels>>,
4616 background: impl Into<Hsla>,
4617 border_widths: impl Into<Edges<Pixels>>,
4618 border_color: impl Into<Hsla>,
4619) -> PaintQuad {
4620 PaintQuad {
4621 bounds,
4622 corner_radii: corner_radii.into(),
4623 background: background.into(),
4624 border_widths: border_widths.into(),
4625 border_color: border_color.into(),
4626 }
4627}
4628
4629/// Creates a filled quad with the given bounds and background color.
4630pub fn fill(bounds: impl Into<Bounds<Pixels>>, background: impl Into<Hsla>) -> PaintQuad {
4631 PaintQuad {
4632 bounds: bounds.into(),
4633 corner_radii: (0.).into(),
4634 background: background.into(),
4635 border_widths: (0.).into(),
4636 border_color: transparent_black(),
4637 }
4638}
4639
4640/// Creates a rectangle outline with the given bounds, border color, and a 1px border width
4641pub fn outline(bounds: impl Into<Bounds<Pixels>>, border_color: impl Into<Hsla>) -> PaintQuad {
4642 PaintQuad {
4643 bounds: bounds.into(),
4644 corner_radii: (0.).into(),
4645 background: transparent_black(),
4646 border_widths: (1.).into(),
4647 border_color: border_color.into(),
4648 }
4649}