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