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