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