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