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};
49use uuid::Uuid;
50
51mod prompts;
52
53pub use prompts::*;
54
55pub(crate) const DEFAULT_WINDOW_SIZE: Size<DevicePixels> =
56 size(DevicePixels(1024), DevicePixels(700));
57
58/// Represents the two different phases when dispatching events.
59#[derive(Default, Copy, Clone, Debug, Eq, PartialEq)]
60pub enum DispatchPhase {
61 /// After the capture phase comes the bubble phase, in which mouse event listeners are
62 /// invoked front to back and keyboard event listeners are invoked from the focused element
63 /// to the root of the element tree. This is the phase you'll most commonly want to use when
64 /// registering event listeners.
65 #[default]
66 Bubble,
67 /// During the initial capture phase, mouse event listeners are invoked back to front, and keyboard
68 /// listeners are invoked from the root of the tree downward toward the focused element. This phase
69 /// is used for special purposes such as clearing the "pressed" state for click events. If
70 /// you stop event propagation during this phase, you need to know what you're doing. Handlers
71 /// outside of the immediate region may rely on detecting non-local events during this phase.
72 Capture,
73}
74
75impl DispatchPhase {
76 /// Returns true if this represents the "bubble" phase.
77 pub fn bubble(self) -> bool {
78 self == DispatchPhase::Bubble
79 }
80
81 /// Returns true if this represents the "capture" phase.
82 pub fn capture(self) -> bool {
83 self == DispatchPhase::Capture
84 }
85}
86
87type AnyObserver = Box<dyn FnMut(&mut WindowContext) -> bool + 'static>;
88
89type AnyWindowFocusListener = Box<dyn FnMut(&FocusEvent, &mut WindowContext) -> bool + 'static>;
90
91struct FocusEvent {
92 previous_focus_path: SmallVec<[FocusId; 8]>,
93 current_focus_path: SmallVec<[FocusId; 8]>,
94}
95
96slotmap::new_key_type! {
97 /// A globally unique identifier for a focusable element.
98 pub struct FocusId;
99}
100
101thread_local! {
102 /// 8MB wasn't quite enough...
103 pub(crate) static ELEMENT_ARENA: RefCell<Arena> = RefCell::new(Arena::new(32 * 1024 * 1024));
104}
105
106impl FocusId {
107 /// Obtains whether the element associated with this handle is currently focused.
108 pub fn is_focused(&self, cx: &WindowContext) -> bool {
109 cx.window.focus == Some(*self)
110 }
111
112 /// Obtains whether the element associated with this handle contains the focused
113 /// element or is itself focused.
114 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
115 cx.focused()
116 .map_or(false, |focused| self.contains(focused.id, cx))
117 }
118
119 /// Obtains whether the element associated with this handle is contained within the
120 /// focused element or is itself focused.
121 pub fn within_focused(&self, cx: &WindowContext) -> bool {
122 let focused = cx.focused();
123 focused.map_or(false, |focused| focused.id.contains(*self, cx))
124 }
125
126 /// Obtains whether this handle contains the given handle in the most recently rendered frame.
127 pub(crate) fn contains(&self, other: Self, cx: &WindowContext) -> bool {
128 cx.window
129 .rendered_frame
130 .dispatch_tree
131 .focus_contains(*self, other)
132 }
133}
134
135/// A handle which can be used to track and manipulate the focused element in a window.
136pub struct FocusHandle {
137 pub(crate) id: FocusId,
138 handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
139}
140
141impl std::fmt::Debug for FocusHandle {
142 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
143 f.write_fmt(format_args!("FocusHandle({:?})", self.id))
144 }
145}
146
147impl FocusHandle {
148 pub(crate) fn new(handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>) -> Self {
149 let id = handles.write().insert(AtomicUsize::new(1));
150 Self {
151 id,
152 handles: handles.clone(),
153 }
154 }
155
156 pub(crate) fn for_id(
157 id: FocusId,
158 handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
159 ) -> Option<Self> {
160 let lock = handles.read();
161 let ref_count = lock.get(id)?;
162 if ref_count.load(SeqCst) == 0 {
163 None
164 } else {
165 ref_count.fetch_add(1, SeqCst);
166 Some(Self {
167 id,
168 handles: handles.clone(),
169 })
170 }
171 }
172
173 /// Converts this focus handle into a weak variant, which does not prevent it from being released.
174 pub fn downgrade(&self) -> WeakFocusHandle {
175 WeakFocusHandle {
176 id: self.id,
177 handles: Arc::downgrade(&self.handles),
178 }
179 }
180
181 /// Moves the focus to the element associated with this handle.
182 pub fn focus(&self, cx: &mut WindowContext) {
183 cx.focus(self)
184 }
185
186 /// Obtains whether the element associated with this handle is currently focused.
187 pub fn is_focused(&self, cx: &WindowContext) -> bool {
188 self.id.is_focused(cx)
189 }
190
191 /// Obtains whether the element associated with this handle contains the focused
192 /// element or is itself focused.
193 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
194 self.id.contains_focused(cx)
195 }
196
197 /// Obtains whether the element associated with this handle is contained within the
198 /// focused element or is itself focused.
199 pub fn within_focused(&self, cx: &WindowContext) -> bool {
200 self.id.within_focused(cx)
201 }
202
203 /// Obtains whether this handle contains the given handle in the most recently rendered frame.
204 pub fn contains(&self, other: &Self, cx: &WindowContext) -> bool {
205 self.id.contains(other.id, cx)
206 }
207
208 /// Dispatch an action on the element that rendered this focus handle
209 pub fn dispatch_action(&self, action: &dyn Action, cx: &mut WindowContext) {
210 if let Some(node_id) = cx
211 .window
212 .rendered_frame
213 .dispatch_tree
214 .focusable_node_id(self.id)
215 {
216 cx.dispatch_action_on_node(node_id, action)
217 }
218 }
219}
220
221impl Clone for FocusHandle {
222 fn clone(&self) -> Self {
223 Self::for_id(self.id, &self.handles).unwrap()
224 }
225}
226
227impl PartialEq for FocusHandle {
228 fn eq(&self, other: &Self) -> bool {
229 self.id == other.id
230 }
231}
232
233impl Eq for FocusHandle {}
234
235impl Drop for FocusHandle {
236 fn drop(&mut self) {
237 self.handles
238 .read()
239 .get(self.id)
240 .unwrap()
241 .fetch_sub(1, SeqCst);
242 }
243}
244
245/// A weak reference to a focus handle.
246#[derive(Clone, Debug)]
247pub struct WeakFocusHandle {
248 pub(crate) id: FocusId,
249 handles: Weak<RwLock<SlotMap<FocusId, AtomicUsize>>>,
250}
251
252impl WeakFocusHandle {
253 /// Attempts to upgrade the [WeakFocusHandle] to a [FocusHandle].
254 pub fn upgrade(&self) -> Option<FocusHandle> {
255 let handles = self.handles.upgrade()?;
256 FocusHandle::for_id(self.id, &handles)
257 }
258}
259
260impl PartialEq for WeakFocusHandle {
261 fn eq(&self, other: &WeakFocusHandle) -> bool {
262 self.id == other.id
263 }
264}
265
266impl Eq for WeakFocusHandle {}
267
268impl PartialEq<FocusHandle> for WeakFocusHandle {
269 fn eq(&self, other: &FocusHandle) -> bool {
270 self.id == other.id
271 }
272}
273
274impl PartialEq<WeakFocusHandle> for FocusHandle {
275 fn eq(&self, other: &WeakFocusHandle) -> bool {
276 self.id == other.id
277 }
278}
279
280/// FocusableView allows users of your view to easily
281/// focus it (using cx.focus_view(view))
282pub trait FocusableView: 'static + Render {
283 /// Returns the focus handle associated with this view.
284 fn focus_handle(&self, cx: &AppContext) -> FocusHandle;
285}
286
287/// ManagedView is a view (like a Modal, Popover, Menu, etc.)
288/// where the lifecycle of the view is handled by another view.
289pub trait ManagedView: FocusableView + EventEmitter<DismissEvent> {}
290
291impl<M: FocusableView + EventEmitter<DismissEvent>> ManagedView for M {}
292
293/// Emitted by implementers of [`ManagedView`] to indicate the view should be dismissed, such as when a view is presented as a modal.
294pub struct DismissEvent;
295
296type FrameCallback = Box<dyn FnOnce(&mut WindowContext)>;
297
298pub(crate) type AnyMouseListener =
299 Box<dyn FnMut(&dyn Any, DispatchPhase, &mut WindowContext) + 'static>;
300
301#[derive(Clone)]
302pub(crate) struct CursorStyleRequest {
303 pub(crate) hitbox_id: HitboxId,
304 pub(crate) style: CursorStyle,
305}
306
307/// An identifier for a [Hitbox].
308#[derive(Copy, Clone, Debug, Default, Eq, PartialEq)]
309pub struct HitboxId(usize);
310
311impl HitboxId {
312 /// Checks if the hitbox with this id is currently hovered.
313 pub fn is_hovered(&self, cx: &WindowContext) -> bool {
314 cx.window.mouse_hit_test.0.contains(self)
315 }
316}
317
318/// A rectangular region that potentially blocks hitboxes inserted prior.
319/// See [WindowContext::insert_hitbox] for more details.
320#[derive(Clone, Debug, Deref)]
321pub struct Hitbox {
322 /// A unique identifier for the hitbox.
323 pub id: HitboxId,
324 /// The bounds of the hitbox.
325 #[deref]
326 pub bounds: Bounds<Pixels>,
327 /// The content mask when the hitbox was inserted.
328 pub content_mask: ContentMask<Pixels>,
329 /// Whether the hitbox occludes other hitboxes inserted prior.
330 pub opaque: bool,
331}
332
333impl Hitbox {
334 /// Checks if the hitbox is currently hovered.
335 pub fn is_hovered(&self, cx: &WindowContext) -> bool {
336 self.id.is_hovered(cx)
337 }
338}
339
340#[derive(Default, Eq, PartialEq)]
341pub(crate) struct HitTest(SmallVec<[HitboxId; 8]>);
342
343/// An identifier for a tooltip.
344#[derive(Copy, Clone, Debug, Default, Eq, PartialEq)]
345pub struct TooltipId(usize);
346
347impl TooltipId {
348 /// Checks if the tooltip is currently hovered.
349 pub fn is_hovered(&self, cx: &WindowContext) -> bool {
350 cx.window
351 .tooltip_bounds
352 .as_ref()
353 .map_or(false, |tooltip_bounds| {
354 tooltip_bounds.id == *self && tooltip_bounds.bounds.contains(&cx.mouse_position())
355 })
356 }
357}
358
359pub(crate) struct TooltipBounds {
360 id: TooltipId,
361 bounds: Bounds<Pixels>,
362}
363
364#[derive(Clone)]
365pub(crate) struct TooltipRequest {
366 id: TooltipId,
367 tooltip: AnyTooltip,
368}
369
370pub(crate) struct DeferredDraw {
371 priority: usize,
372 parent_node: DispatchNodeId,
373 element_id_stack: SmallVec<[ElementId; 32]>,
374 text_style_stack: Vec<TextStyleRefinement>,
375 element: Option<AnyElement>,
376 absolute_offset: Point<Pixels>,
377 prepaint_range: Range<PrepaintStateIndex>,
378 paint_range: Range<PaintIndex>,
379}
380
381pub(crate) struct Frame {
382 pub(crate) focus: Option<FocusId>,
383 pub(crate) window_active: bool,
384 pub(crate) element_states: FxHashMap<(GlobalElementId, TypeId), ElementStateBox>,
385 accessed_element_states: Vec<(GlobalElementId, TypeId)>,
386 pub(crate) mouse_listeners: Vec<Option<AnyMouseListener>>,
387 pub(crate) dispatch_tree: DispatchTree,
388 pub(crate) scene: Scene,
389 pub(crate) hitboxes: Vec<Hitbox>,
390 pub(crate) deferred_draws: Vec<DeferredDraw>,
391 pub(crate) input_handlers: Vec<Option<PlatformInputHandler>>,
392 pub(crate) tooltip_requests: Vec<Option<TooltipRequest>>,
393 pub(crate) cursor_styles: Vec<CursorStyleRequest>,
394 #[cfg(any(test, feature = "test-support"))]
395 pub(crate) debug_bounds: FxHashMap<String, Bounds<Pixels>>,
396}
397
398#[derive(Clone, Default)]
399pub(crate) struct PrepaintStateIndex {
400 hitboxes_index: usize,
401 tooltips_index: usize,
402 deferred_draws_index: usize,
403 dispatch_tree_index: usize,
404 accessed_element_states_index: usize,
405 line_layout_index: LineLayoutIndex,
406}
407
408#[derive(Clone, Default)]
409pub(crate) struct PaintIndex {
410 scene_index: usize,
411 mouse_listeners_index: usize,
412 input_handlers_index: usize,
413 cursor_styles_index: usize,
414 accessed_element_states_index: usize,
415 line_layout_index: LineLayoutIndex,
416}
417
418impl Frame {
419 pub(crate) fn new(dispatch_tree: DispatchTree) -> Self {
420 Frame {
421 focus: None,
422 window_active: false,
423 element_states: FxHashMap::default(),
424 accessed_element_states: Vec::new(),
425 mouse_listeners: Vec::new(),
426 dispatch_tree,
427 scene: Scene::default(),
428 hitboxes: Vec::new(),
429 deferred_draws: Vec::new(),
430 input_handlers: Vec::new(),
431 tooltip_requests: Vec::new(),
432 cursor_styles: Vec::new(),
433
434 #[cfg(any(test, feature = "test-support"))]
435 debug_bounds: FxHashMap::default(),
436 }
437 }
438
439 pub(crate) fn clear(&mut self) {
440 self.element_states.clear();
441 self.accessed_element_states.clear();
442 self.mouse_listeners.clear();
443 self.dispatch_tree.clear();
444 self.scene.clear();
445 self.input_handlers.clear();
446 self.tooltip_requests.clear();
447 self.cursor_styles.clear();
448 self.hitboxes.clear();
449 self.deferred_draws.clear();
450 }
451
452 pub(crate) fn hit_test(&self, position: Point<Pixels>) -> HitTest {
453 let mut hit_test = HitTest::default();
454 for hitbox in self.hitboxes.iter().rev() {
455 let bounds = hitbox.bounds.intersect(&hitbox.content_mask.bounds);
456 if bounds.contains(&position) {
457 hit_test.0.push(hitbox.id);
458 if hitbox.opaque {
459 break;
460 }
461 }
462 }
463 hit_test
464 }
465
466 pub(crate) fn focus_path(&self) -> SmallVec<[FocusId; 8]> {
467 self.focus
468 .map(|focus_id| self.dispatch_tree.focus_path(focus_id))
469 .unwrap_or_default()
470 }
471
472 pub(crate) fn finish(&mut self, prev_frame: &mut Self) {
473 for element_state_key in &self.accessed_element_states {
474 if let Some((element_state_key, element_state)) =
475 prev_frame.element_states.remove_entry(element_state_key)
476 {
477 self.element_states.insert(element_state_key, element_state);
478 }
479 }
480
481 self.scene.finish();
482 }
483}
484
485// Holds the state for a specific window.
486#[doc(hidden)]
487pub struct Window {
488 pub(crate) handle: AnyWindowHandle,
489 pub(crate) removed: bool,
490 pub(crate) platform_window: Box<dyn PlatformWindow>,
491 display_id: Option<DisplayId>,
492 sprite_atlas: Arc<dyn PlatformAtlas>,
493 text_system: Arc<WindowTextSystem>,
494 rem_size: Pixels,
495 /// The stack of override values for the window's rem size.
496 ///
497 /// This is used by `with_rem_size` to allow rendering an element tree with
498 /// a given rem size.
499 rem_size_override_stack: SmallVec<[Pixels; 8]>,
500 pub(crate) viewport_size: Size<Pixels>,
501 layout_engine: Option<TaffyLayoutEngine>,
502 pub(crate) root_view: Option<AnyView>,
503 pub(crate) element_id_stack: SmallVec<[ElementId; 32]>,
504 pub(crate) text_style_stack: Vec<TextStyleRefinement>,
505 pub(crate) element_offset_stack: Vec<Point<Pixels>>,
506 pub(crate) content_mask_stack: Vec<ContentMask<Pixels>>,
507 pub(crate) requested_autoscroll: Option<Bounds<Pixels>>,
508 pub(crate) rendered_frame: Frame,
509 pub(crate) next_frame: Frame,
510 pub(crate) next_hitbox_id: HitboxId,
511 pub(crate) next_tooltip_id: TooltipId,
512 pub(crate) tooltip_bounds: Option<TooltipBounds>,
513 next_frame_callbacks: Rc<RefCell<Vec<FrameCallback>>>,
514 pub(crate) dirty_views: FxHashSet<EntityId>,
515 pub(crate) focus_handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
516 focus_listeners: SubscriberSet<(), AnyWindowFocusListener>,
517 focus_lost_listeners: SubscriberSet<(), AnyObserver>,
518 default_prevented: bool,
519 mouse_position: Point<Pixels>,
520 mouse_hit_test: HitTest,
521 modifiers: Modifiers,
522 scale_factor: f32,
523 bounds_observers: SubscriberSet<(), AnyObserver>,
524 appearance: WindowAppearance,
525 appearance_observers: SubscriberSet<(), AnyObserver>,
526 active: Rc<Cell<bool>>,
527 pub(crate) dirty: Rc<Cell<bool>>,
528 pub(crate) needs_present: Rc<Cell<bool>>,
529 pub(crate) last_input_timestamp: Rc<Cell<Instant>>,
530 pub(crate) refreshing: bool,
531 pub(crate) draw_phase: DrawPhase,
532 activation_observers: SubscriberSet<(), AnyObserver>,
533 pub(crate) focus: Option<FocusId>,
534 focus_enabled: bool,
535 pending_input: Option<PendingInput>,
536 prompt: Option<RenderablePromptHandle>,
537}
538
539#[derive(Clone, Copy, Debug, Eq, PartialEq)]
540pub(crate) enum DrawPhase {
541 None,
542 Prepaint,
543 Paint,
544 Focus,
545}
546
547#[derive(Default, Debug)]
548struct PendingInput {
549 keystrokes: SmallVec<[Keystroke; 1]>,
550 bindings: SmallVec<[KeyBinding; 1]>,
551 focus: Option<FocusId>,
552 timer: Option<Task<()>>,
553}
554
555impl PendingInput {
556 fn input(&self) -> String {
557 self.keystrokes
558 .iter()
559 .flat_map(|k| k.ime_key.clone())
560 .collect::<Vec<String>>()
561 .join("")
562 }
563
564 fn used_by_binding(&self, binding: &KeyBinding) -> bool {
565 if self.keystrokes.is_empty() {
566 return true;
567 }
568 let keystroke = &self.keystrokes[0];
569 for candidate in keystroke.match_candidates() {
570 if binding.match_keystrokes(&[candidate]) == KeyMatch::Pending {
571 return true;
572 }
573 }
574 false
575 }
576}
577
578pub(crate) struct ElementStateBox {
579 pub(crate) inner: Box<dyn Any>,
580 #[cfg(debug_assertions)]
581 pub(crate) type_name: &'static str,
582}
583
584fn default_bounds(display_id: Option<DisplayId>, cx: &mut AppContext) -> Bounds<DevicePixels> {
585 const DEFAULT_WINDOW_OFFSET: Point<DevicePixels> = point(DevicePixels(0), DevicePixels(35));
586
587 cx.active_window()
588 .and_then(|w| w.update(cx, |_, cx| cx.bounds()).ok())
589 .map(|bounds| bounds.map_origin(|origin| origin + DEFAULT_WINDOW_OFFSET))
590 .unwrap_or_else(|| {
591 let display = display_id
592 .map(|id| cx.find_display(id))
593 .unwrap_or_else(|| cx.primary_display());
594
595 display
596 .map(|display| display.default_bounds())
597 .unwrap_or_else(|| {
598 Bounds::new(point(DevicePixels(0), DevicePixels(0)), DEFAULT_WINDOW_SIZE)
599 })
600 })
601}
602
603impl Window {
604 pub(crate) fn new(
605 handle: AnyWindowHandle,
606 options: WindowOptions,
607 cx: &mut AppContext,
608 ) -> Self {
609 let WindowOptions {
610 window_bounds,
611 titlebar,
612 focus,
613 show,
614 kind,
615 is_movable,
616 display_id,
617 window_background,
618 app_id,
619 } = options;
620
621 let bounds = window_bounds
622 .map(|bounds| bounds.get_bounds())
623 .unwrap_or_else(|| default_bounds(display_id, cx));
624 let mut platform_window = cx.platform.open_window(
625 handle,
626 WindowParams {
627 bounds,
628 titlebar,
629 kind,
630 is_movable,
631 focus,
632 show,
633 display_id,
634 window_background,
635 },
636 );
637 let display_id = platform_window.display().map(|display| display.id());
638 let sprite_atlas = platform_window.sprite_atlas();
639 let mouse_position = platform_window.mouse_position();
640 let modifiers = platform_window.modifiers();
641 let content_size = platform_window.content_size();
642 let scale_factor = platform_window.scale_factor();
643 let appearance = platform_window.appearance();
644 let text_system = Arc::new(WindowTextSystem::new(cx.text_system().clone()));
645 let dirty = Rc::new(Cell::new(true));
646 let active = Rc::new(Cell::new(platform_window.is_active()));
647 let needs_present = Rc::new(Cell::new(false));
648 let next_frame_callbacks: Rc<RefCell<Vec<FrameCallback>>> = Default::default();
649 let last_input_timestamp = Rc::new(Cell::new(Instant::now()));
650
651 if let Some(ref window_open_state) = window_bounds {
652 match window_open_state {
653 WindowBounds::Fullscreen(_) => platform_window.toggle_fullscreen(),
654 WindowBounds::Maximized(_) => platform_window.zoom(),
655 WindowBounds::Windowed(_) => {}
656 }
657 }
658
659 platform_window.on_close(Box::new({
660 let mut cx = cx.to_async();
661 move || {
662 let _ = handle.update(&mut cx, |_, cx| cx.remove_window());
663 }
664 }));
665 platform_window.on_request_frame(Box::new({
666 let mut cx = cx.to_async();
667 let dirty = dirty.clone();
668 let active = active.clone();
669 let needs_present = needs_present.clone();
670 let next_frame_callbacks = next_frame_callbacks.clone();
671 let last_input_timestamp = last_input_timestamp.clone();
672 move || {
673 let next_frame_callbacks = next_frame_callbacks.take();
674 if !next_frame_callbacks.is_empty() {
675 handle
676 .update(&mut cx, |_, cx| {
677 for callback in next_frame_callbacks {
678 callback(cx);
679 }
680 })
681 .log_err();
682 }
683
684 // Keep presenting the current scene for 1 extra second since the
685 // last input to prevent the display from underclocking the refresh rate.
686 let needs_present = needs_present.get()
687 || (active.get()
688 && last_input_timestamp.get().elapsed() < Duration::from_secs(1));
689
690 if dirty.get() {
691 measure("frame duration", || {
692 handle
693 .update(&mut cx, |_, cx| {
694 cx.draw();
695 cx.present();
696 })
697 .log_err();
698 })
699 } else if needs_present {
700 handle.update(&mut cx, |_, cx| cx.present()).log_err();
701 }
702
703 handle
704 .update(&mut cx, |_, cx| {
705 cx.complete_frame();
706 })
707 .log_err();
708 }
709 }));
710 platform_window.on_resize(Box::new({
711 let mut cx = cx.to_async();
712 move |_, _| {
713 handle
714 .update(&mut cx, |_, cx| cx.bounds_changed())
715 .log_err();
716 }
717 }));
718 platform_window.on_moved(Box::new({
719 let mut cx = cx.to_async();
720 move || {
721 handle
722 .update(&mut cx, |_, cx| cx.bounds_changed())
723 .log_err();
724 }
725 }));
726 platform_window.on_appearance_changed(Box::new({
727 let mut cx = cx.to_async();
728 move || {
729 handle
730 .update(&mut cx, |_, cx| cx.appearance_changed())
731 .log_err();
732 }
733 }));
734 platform_window.on_active_status_change(Box::new({
735 let mut cx = cx.to_async();
736 move |active| {
737 handle
738 .update(&mut cx, |_, cx| {
739 cx.window.active.set(active);
740 cx.window
741 .activation_observers
742 .clone()
743 .retain(&(), |callback| callback(cx));
744 cx.refresh();
745 })
746 .log_err();
747 }
748 }));
749
750 platform_window.on_input({
751 let mut cx = cx.to_async();
752 Box::new(move |event| {
753 handle
754 .update(&mut cx, |_, cx| cx.dispatch_event(event))
755 .log_err()
756 .unwrap_or(DispatchEventResult::default())
757 })
758 });
759
760 if let Some(app_id) = app_id {
761 platform_window.set_app_id(&app_id);
762 }
763
764 Window {
765 handle,
766 removed: false,
767 platform_window,
768 display_id,
769 sprite_atlas,
770 text_system,
771 rem_size: px(16.),
772 rem_size_override_stack: SmallVec::new(),
773 viewport_size: content_size,
774 layout_engine: Some(TaffyLayoutEngine::new()),
775 root_view: None,
776 element_id_stack: SmallVec::default(),
777 text_style_stack: Vec::new(),
778 element_offset_stack: Vec::new(),
779 content_mask_stack: Vec::new(),
780 requested_autoscroll: None,
781 rendered_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
782 next_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
783 next_frame_callbacks,
784 next_hitbox_id: HitboxId::default(),
785 next_tooltip_id: TooltipId::default(),
786 tooltip_bounds: None,
787 dirty_views: FxHashSet::default(),
788 focus_handles: Arc::new(RwLock::new(SlotMap::with_key())),
789 focus_listeners: SubscriberSet::new(),
790 focus_lost_listeners: SubscriberSet::new(),
791 default_prevented: true,
792 mouse_position,
793 mouse_hit_test: HitTest::default(),
794 modifiers,
795 scale_factor,
796 bounds_observers: SubscriberSet::new(),
797 appearance,
798 appearance_observers: SubscriberSet::new(),
799 active,
800 dirty,
801 needs_present,
802 last_input_timestamp,
803 refreshing: false,
804 draw_phase: DrawPhase::None,
805 activation_observers: SubscriberSet::new(),
806 focus: None,
807 focus_enabled: true,
808 pending_input: None,
809 prompt: None,
810 }
811 }
812 fn new_focus_listener(
813 &mut self,
814 value: AnyWindowFocusListener,
815 ) -> (Subscription, impl FnOnce()) {
816 self.focus_listeners.insert((), value)
817 }
818}
819
820#[derive(Clone, Debug, Default, PartialEq, Eq)]
821pub(crate) struct DispatchEventResult {
822 pub propagate: bool,
823 pub default_prevented: bool,
824}
825
826/// Indicates which region of the window is visible. Content falling outside of this mask will not be
827/// rendered. Currently, only rectangular content masks are supported, but we give the mask its own type
828/// to leave room to support more complex shapes in the future.
829#[derive(Clone, Debug, Default, PartialEq, Eq)]
830#[repr(C)]
831pub struct ContentMask<P: Clone + Default + Debug> {
832 /// The bounds
833 pub bounds: Bounds<P>,
834}
835
836impl ContentMask<Pixels> {
837 /// Scale the content mask's pixel units by the given scaling factor.
838 pub fn scale(&self, factor: f32) -> ContentMask<ScaledPixels> {
839 ContentMask {
840 bounds: self.bounds.scale(factor),
841 }
842 }
843
844 /// Intersect the content mask with the given content mask.
845 pub fn intersect(&self, other: &Self) -> Self {
846 let bounds = self.bounds.intersect(&other.bounds);
847 ContentMask { bounds }
848 }
849}
850
851/// Provides access to application state in the context of a single window. Derefs
852/// to an [`AppContext`], so you can also pass a [`WindowContext`] to any method that takes
853/// an [`AppContext`] and call any [`AppContext`] methods.
854pub struct WindowContext<'a> {
855 pub(crate) app: &'a mut AppContext,
856 pub(crate) window: &'a mut Window,
857}
858
859impl<'a> WindowContext<'a> {
860 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window) -> Self {
861 Self { app, window }
862 }
863
864 /// Obtain a handle to the window that belongs to this context.
865 pub fn window_handle(&self) -> AnyWindowHandle {
866 self.window.handle
867 }
868
869 /// Mark the window as dirty, scheduling it to be redrawn on the next frame.
870 pub fn refresh(&mut self) {
871 if self.window.draw_phase == DrawPhase::None {
872 self.window.refreshing = true;
873 self.window.dirty.set(true);
874 }
875 }
876
877 /// Indicate that this view has changed, which will invoke any observers and also mark the window as dirty.
878 /// If this view or any of its ancestors are *cached*, notifying it will cause it or its ancestors to be redrawn.
879 pub fn notify(&mut self, view_id: EntityId) {
880 for view_id in self
881 .window
882 .rendered_frame
883 .dispatch_tree
884 .view_path(view_id)
885 .into_iter()
886 .rev()
887 {
888 if !self.window.dirty_views.insert(view_id) {
889 break;
890 }
891 }
892
893 if self.window.draw_phase == DrawPhase::None {
894 self.window.dirty.set(true);
895 self.app.push_effect(Effect::Notify { emitter: view_id });
896 }
897 }
898
899 /// Close this window.
900 pub fn remove_window(&mut self) {
901 self.window.removed = true;
902 }
903
904 /// Obtain a new [`FocusHandle`], which allows you to track and manipulate the keyboard focus
905 /// for elements rendered within this window.
906 pub fn focus_handle(&mut self) -> FocusHandle {
907 FocusHandle::new(&self.window.focus_handles)
908 }
909
910 /// Obtain the currently focused [`FocusHandle`]. If no elements are focused, returns `None`.
911 pub fn focused(&self) -> Option<FocusHandle> {
912 self.window
913 .focus
914 .and_then(|id| FocusHandle::for_id(id, &self.window.focus_handles))
915 }
916
917 /// Move focus to the element associated with the given [`FocusHandle`].
918 pub fn focus(&mut self, handle: &FocusHandle) {
919 if !self.window.focus_enabled || self.window.focus == Some(handle.id) {
920 return;
921 }
922
923 self.window.focus = Some(handle.id);
924 self.window
925 .rendered_frame
926 .dispatch_tree
927 .clear_pending_keystrokes();
928 self.refresh();
929 }
930
931 /// Remove focus from all elements within this context's window.
932 pub fn blur(&mut self) {
933 if !self.window.focus_enabled {
934 return;
935 }
936
937 self.window.focus = None;
938 self.refresh();
939 }
940
941 /// Blur the window and don't allow anything in it to be focused again.
942 pub fn disable_focus(&mut self) {
943 self.blur();
944 self.window.focus_enabled = false;
945 }
946
947 /// Accessor for the text system.
948 pub fn text_system(&self) -> &Arc<WindowTextSystem> {
949 &self.window.text_system
950 }
951
952 /// The current text style. Which is composed of all the style refinements provided to `with_text_style`.
953 pub fn text_style(&self) -> TextStyle {
954 let mut style = TextStyle::default();
955 for refinement in &self.window.text_style_stack {
956 style.refine(refinement);
957 }
958 style
959 }
960
961 /// Check if the platform window is maximized
962 /// On some platforms (namely Windows) this is different than the bounds being the size of the display
963 pub fn is_maximized(&self) -> bool {
964 self.window.platform_window.is_maximized()
965 }
966
967 /// Return the `WindowBounds` to indicate that how a window should be opened
968 /// after it has been closed
969 pub fn window_bounds(&self) -> WindowBounds {
970 self.window.platform_window.window_bounds()
971 }
972
973 /// Dispatch the given action on the currently focused element.
974 pub fn dispatch_action(&mut self, action: Box<dyn Action>) {
975 let focus_handle = self.focused();
976
977 let window = self.window.handle;
978 self.app.defer(move |cx| {
979 window
980 .update(cx, |_, cx| {
981 let node_id = focus_handle
982 .and_then(|handle| {
983 cx.window
984 .rendered_frame
985 .dispatch_tree
986 .focusable_node_id(handle.id)
987 })
988 .unwrap_or_else(|| cx.window.rendered_frame.dispatch_tree.root_node_id());
989
990 cx.dispatch_action_on_node(node_id, action.as_ref());
991 })
992 .log_err();
993 })
994 }
995
996 pub(crate) fn dispatch_keystroke_observers(
997 &mut self,
998 event: &dyn Any,
999 action: Option<Box<dyn Action>>,
1000 ) {
1001 let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() else {
1002 return;
1003 };
1004
1005 self.keystroke_observers
1006 .clone()
1007 .retain(&(), move |callback| {
1008 (callback)(
1009 &KeystrokeEvent {
1010 keystroke: key_down_event.keystroke.clone(),
1011 action: action.as_ref().map(|action| action.boxed_clone()),
1012 },
1013 self,
1014 );
1015 true
1016 });
1017 }
1018
1019 pub(crate) fn clear_pending_keystrokes(&mut self) {
1020 self.window
1021 .rendered_frame
1022 .dispatch_tree
1023 .clear_pending_keystrokes();
1024 self.window
1025 .next_frame
1026 .dispatch_tree
1027 .clear_pending_keystrokes();
1028 }
1029
1030 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
1031 /// that are currently on the stack to be returned to the app.
1032 pub fn defer(&mut self, f: impl FnOnce(&mut WindowContext) + 'static) {
1033 let handle = self.window.handle;
1034 self.app.defer(move |cx| {
1035 handle.update(cx, |_, cx| f(cx)).ok();
1036 });
1037 }
1038
1039 /// Subscribe to events emitted by a model or view.
1040 /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
1041 /// 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.
1042 pub fn subscribe<Emitter, E, Evt>(
1043 &mut self,
1044 entity: &E,
1045 mut on_event: impl FnMut(E, &Evt, &mut WindowContext<'_>) + 'static,
1046 ) -> Subscription
1047 where
1048 Emitter: EventEmitter<Evt>,
1049 E: Entity<Emitter>,
1050 Evt: 'static,
1051 {
1052 let entity_id = entity.entity_id();
1053 let entity = entity.downgrade();
1054 let window_handle = self.window.handle;
1055 self.app.new_subscription(
1056 entity_id,
1057 (
1058 TypeId::of::<Evt>(),
1059 Box::new(move |event, cx| {
1060 window_handle
1061 .update(cx, |_, cx| {
1062 if let Some(handle) = E::upgrade_from(&entity) {
1063 let event = event.downcast_ref().expect("invalid event type");
1064 on_event(handle, event, cx);
1065 true
1066 } else {
1067 false
1068 }
1069 })
1070 .unwrap_or(false)
1071 }),
1072 ),
1073 )
1074 }
1075
1076 /// Creates an [`AsyncWindowContext`], which has a static lifetime and can be held across
1077 /// await points in async code.
1078 pub fn to_async(&self) -> AsyncWindowContext {
1079 AsyncWindowContext::new(self.app.to_async(), self.window.handle)
1080 }
1081
1082 /// Schedule the given closure to be run directly after the current frame is rendered.
1083 pub fn on_next_frame(&mut self, callback: impl FnOnce(&mut WindowContext) + 'static) {
1084 RefCell::borrow_mut(&self.window.next_frame_callbacks).push(Box::new(callback));
1085 }
1086
1087 /// Spawn the future returned by the given closure on the application thread pool.
1088 /// The closure is provided a handle to the current window and an `AsyncWindowContext` for
1089 /// use within your future.
1090 pub fn spawn<Fut, R>(&mut self, f: impl FnOnce(AsyncWindowContext) -> Fut) -> Task<R>
1091 where
1092 R: 'static,
1093 Fut: Future<Output = R> + 'static,
1094 {
1095 self.app
1096 .spawn(|app| f(AsyncWindowContext::new(app, self.window.handle)))
1097 }
1098
1099 fn bounds_changed(&mut self) {
1100 self.window.scale_factor = self.window.platform_window.scale_factor();
1101 self.window.viewport_size = self.window.platform_window.content_size();
1102 self.window.display_id = self
1103 .window
1104 .platform_window
1105 .display()
1106 .map(|display| display.id());
1107
1108 self.refresh();
1109
1110 self.window
1111 .bounds_observers
1112 .clone()
1113 .retain(&(), |callback| callback(self));
1114 }
1115
1116 /// Returns the bounds of the current window in the global coordinate space, which could span across multiple displays.
1117 pub fn bounds(&self) -> Bounds<DevicePixels> {
1118 self.window.platform_window.bounds()
1119 }
1120
1121 /// Returns whether or not the window is currently fullscreen
1122 pub fn is_fullscreen(&self) -> bool {
1123 self.window.platform_window.is_fullscreen()
1124 }
1125
1126 fn appearance_changed(&mut self) {
1127 self.window.appearance = self.window.platform_window.appearance();
1128
1129 self.window
1130 .appearance_observers
1131 .clone()
1132 .retain(&(), |callback| callback(self));
1133 }
1134
1135 /// Returns the appearance of the current window.
1136 pub fn appearance(&self) -> WindowAppearance {
1137 self.window.appearance
1138 }
1139
1140 /// Returns the size of the drawable area within the window.
1141 pub fn viewport_size(&self) -> Size<Pixels> {
1142 self.window.viewport_size
1143 }
1144
1145 /// Returns whether this window is focused by the operating system (receiving key events).
1146 pub fn is_window_active(&self) -> bool {
1147 self.window.active.get()
1148 }
1149
1150 /// Toggle zoom on the window.
1151 pub fn zoom_window(&self) {
1152 self.window.platform_window.zoom();
1153 }
1154
1155 /// Opens the native title bar context menu, useful when implementing client side decorations (Wayland and X11)
1156 pub fn show_window_menu(&self, position: Point<Pixels>) {
1157 self.window.platform_window.show_window_menu(position)
1158 }
1159
1160 /// Tells the compositor to take control of window movement (Wayland and X11)
1161 ///
1162 /// Events may not be received during a move operation.
1163 pub fn start_system_move(&self) {
1164 self.window.platform_window.start_system_move()
1165 }
1166
1167 /// Returns whether the title bar window controls need to be rendered by the application (Wayland and X11)
1168 pub fn should_render_window_controls(&self) -> bool {
1169 self.window.platform_window.should_render_window_controls()
1170 }
1171
1172 /// Updates the window's title at the platform level.
1173 pub fn set_window_title(&mut self, title: &str) {
1174 self.window.platform_window.set_title(title);
1175 }
1176
1177 /// Sets the application identifier.
1178 pub fn set_app_id(&mut self, app_id: &str) {
1179 self.window.platform_window.set_app_id(app_id);
1180 }
1181
1182 /// Sets the window background appearance.
1183 pub fn set_background_appearance(&mut self, background_appearance: WindowBackgroundAppearance) {
1184 self.window
1185 .platform_window
1186 .set_background_appearance(background_appearance);
1187 }
1188
1189 /// Mark the window as dirty at the platform level.
1190 pub fn set_window_edited(&mut self, edited: bool) {
1191 self.window.platform_window.set_edited(edited);
1192 }
1193
1194 /// Determine the display on which the window is visible.
1195 pub fn display(&self) -> Option<Rc<dyn PlatformDisplay>> {
1196 self.platform
1197 .displays()
1198 .into_iter()
1199 .find(|display| Some(display.id()) == self.window.display_id)
1200 }
1201
1202 /// Show the platform character palette.
1203 pub fn show_character_palette(&self) {
1204 self.window.platform_window.show_character_palette();
1205 }
1206
1207 /// The scale factor of the display associated with the window. For example, it could
1208 /// return 2.0 for a "retina" display, indicating that each logical pixel should actually
1209 /// be rendered as two pixels on screen.
1210 pub fn scale_factor(&self) -> f32 {
1211 self.window.scale_factor
1212 }
1213
1214 /// The size of an em for the base font of the application. Adjusting this value allows the
1215 /// UI to scale, just like zooming a web page.
1216 pub fn rem_size(&self) -> Pixels {
1217 self.window
1218 .rem_size_override_stack
1219 .last()
1220 .copied()
1221 .unwrap_or(self.window.rem_size)
1222 }
1223
1224 /// Sets the size of an em for the base font of the application. Adjusting this value allows the
1225 /// UI to scale, just like zooming a web page.
1226 pub fn set_rem_size(&mut self, rem_size: impl Into<Pixels>) {
1227 self.window.rem_size = rem_size.into();
1228 }
1229
1230 /// Executes the provided function with the specified rem size.
1231 ///
1232 /// This method must only be called as part of element drawing.
1233 pub fn with_rem_size<F, R>(&mut self, rem_size: Option<impl Into<Pixels>>, f: F) -> R
1234 where
1235 F: FnOnce(&mut Self) -> R,
1236 {
1237 debug_assert!(
1238 matches!(
1239 self.window.draw_phase,
1240 DrawPhase::Prepaint | DrawPhase::Paint
1241 ),
1242 "this method can only be called during request_layout, prepaint, or paint"
1243 );
1244
1245 if let Some(rem_size) = rem_size {
1246 self.window.rem_size_override_stack.push(rem_size.into());
1247 let result = f(self);
1248 self.window.rem_size_override_stack.pop();
1249 result
1250 } else {
1251 f(self)
1252 }
1253 }
1254
1255 /// The line height associated with the current text style.
1256 pub fn line_height(&self) -> Pixels {
1257 let rem_size = self.rem_size();
1258 let text_style = self.text_style();
1259 text_style
1260 .line_height
1261 .to_pixels(text_style.font_size, rem_size)
1262 }
1263
1264 /// Call to prevent the default action of an event. Currently only used to prevent
1265 /// parent elements from becoming focused on mouse down.
1266 pub fn prevent_default(&mut self) {
1267 self.window.default_prevented = true;
1268 }
1269
1270 /// Obtain whether default has been prevented for the event currently being dispatched.
1271 pub fn default_prevented(&self) -> bool {
1272 self.window.default_prevented
1273 }
1274
1275 /// Determine whether the given action is available along the dispatch path to the currently focused element.
1276 pub fn is_action_available(&self, action: &dyn Action) -> bool {
1277 let target = self
1278 .focused()
1279 .and_then(|focused_handle| {
1280 self.window
1281 .rendered_frame
1282 .dispatch_tree
1283 .focusable_node_id(focused_handle.id)
1284 })
1285 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
1286 self.window
1287 .rendered_frame
1288 .dispatch_tree
1289 .is_action_available(action, target)
1290 }
1291
1292 /// The position of the mouse relative to the window.
1293 pub fn mouse_position(&self) -> Point<Pixels> {
1294 self.window.mouse_position
1295 }
1296
1297 /// The current state of the keyboard's modifiers
1298 pub fn modifiers(&self) -> Modifiers {
1299 self.window.modifiers
1300 }
1301
1302 fn complete_frame(&self) {
1303 self.window.platform_window.completed_frame();
1304 }
1305
1306 /// Produces a new frame and assigns it to `rendered_frame`. To actually show
1307 /// the contents of the new [Scene], use [present].
1308 #[profiling::function]
1309 pub fn draw(&mut self) {
1310 self.window.dirty.set(false);
1311 self.window.requested_autoscroll = None;
1312
1313 // Restore the previously-used input handler.
1314 if let Some(input_handler) = self.window.platform_window.take_input_handler() {
1315 self.window
1316 .rendered_frame
1317 .input_handlers
1318 .push(Some(input_handler));
1319 }
1320
1321 self.draw_roots();
1322 self.window.dirty_views.clear();
1323
1324 self.window
1325 .next_frame
1326 .dispatch_tree
1327 .preserve_pending_keystrokes(
1328 &mut self.window.rendered_frame.dispatch_tree,
1329 self.window.focus,
1330 );
1331 self.window.next_frame.focus = self.window.focus;
1332 self.window.next_frame.window_active = self.window.active.get();
1333
1334 // Register requested input handler with the platform window.
1335 if let Some(input_handler) = self.window.next_frame.input_handlers.pop() {
1336 self.window
1337 .platform_window
1338 .set_input_handler(input_handler.unwrap());
1339 }
1340
1341 self.window.layout_engine.as_mut().unwrap().clear();
1342 self.text_system().finish_frame();
1343 self.window
1344 .next_frame
1345 .finish(&mut self.window.rendered_frame);
1346 ELEMENT_ARENA.with_borrow_mut(|element_arena| {
1347 let percentage = (element_arena.len() as f32 / element_arena.capacity() as f32) * 100.;
1348 if percentage >= 80. {
1349 log::warn!("elevated element arena occupation: {}.", percentage);
1350 }
1351 element_arena.clear();
1352 });
1353
1354 self.window.draw_phase = DrawPhase::Focus;
1355 let previous_focus_path = self.window.rendered_frame.focus_path();
1356 let previous_window_active = self.window.rendered_frame.window_active;
1357 mem::swap(&mut self.window.rendered_frame, &mut self.window.next_frame);
1358 self.window.next_frame.clear();
1359 let current_focus_path = self.window.rendered_frame.focus_path();
1360 let current_window_active = self.window.rendered_frame.window_active;
1361
1362 if previous_focus_path != current_focus_path
1363 || previous_window_active != current_window_active
1364 {
1365 if !previous_focus_path.is_empty() && current_focus_path.is_empty() {
1366 self.window
1367 .focus_lost_listeners
1368 .clone()
1369 .retain(&(), |listener| listener(self));
1370 }
1371
1372 let event = FocusEvent {
1373 previous_focus_path: if previous_window_active {
1374 previous_focus_path
1375 } else {
1376 Default::default()
1377 },
1378 current_focus_path: if current_window_active {
1379 current_focus_path
1380 } else {
1381 Default::default()
1382 },
1383 };
1384 self.window
1385 .focus_listeners
1386 .clone()
1387 .retain(&(), |listener| listener(&event, self));
1388 }
1389
1390 self.reset_cursor_style();
1391 self.window.refreshing = false;
1392 self.window.draw_phase = DrawPhase::None;
1393 self.window.needs_present.set(true);
1394 }
1395
1396 #[profiling::function]
1397 fn present(&self) {
1398 self.window
1399 .platform_window
1400 .draw(&self.window.rendered_frame.scene);
1401 self.window.needs_present.set(false);
1402 profiling::finish_frame!();
1403 }
1404
1405 fn draw_roots(&mut self) {
1406 self.window.draw_phase = DrawPhase::Prepaint;
1407 self.window.tooltip_bounds.take();
1408
1409 // Layout all root elements.
1410 let mut root_element = self.window.root_view.as_ref().unwrap().clone().into_any();
1411 root_element.prepaint_as_root(Point::default(), self.window.viewport_size.into(), self);
1412
1413 let mut sorted_deferred_draws =
1414 (0..self.window.next_frame.deferred_draws.len()).collect::<SmallVec<[_; 8]>>();
1415 sorted_deferred_draws.sort_by_key(|ix| self.window.next_frame.deferred_draws[*ix].priority);
1416 self.prepaint_deferred_draws(&sorted_deferred_draws);
1417
1418 let mut prompt_element = None;
1419 let mut active_drag_element = None;
1420 let mut tooltip_element = None;
1421 if let Some(prompt) = self.window.prompt.take() {
1422 let mut element = prompt.view.any_view().into_any();
1423 element.prepaint_as_root(Point::default(), self.window.viewport_size.into(), self);
1424 prompt_element = Some(element);
1425 self.window.prompt = Some(prompt);
1426 } else if let Some(active_drag) = self.app.active_drag.take() {
1427 let mut element = active_drag.view.clone().into_any();
1428 let offset = self.mouse_position() - active_drag.cursor_offset;
1429 element.prepaint_as_root(offset, AvailableSpace::min_size(), self);
1430 active_drag_element = Some(element);
1431 self.app.active_drag = Some(active_drag);
1432 } else {
1433 tooltip_element = self.prepaint_tooltip();
1434 }
1435
1436 self.window.mouse_hit_test = self.window.next_frame.hit_test(self.window.mouse_position);
1437
1438 // Now actually paint the elements.
1439 self.window.draw_phase = DrawPhase::Paint;
1440 root_element.paint(self);
1441
1442 self.paint_deferred_draws(&sorted_deferred_draws);
1443
1444 if let Some(mut prompt_element) = prompt_element {
1445 prompt_element.paint(self)
1446 } else if let Some(mut drag_element) = active_drag_element {
1447 drag_element.paint(self);
1448 } else if let Some(mut tooltip_element) = tooltip_element {
1449 tooltip_element.paint(self);
1450 }
1451 }
1452
1453 fn prepaint_tooltip(&mut self) -> Option<AnyElement> {
1454 let tooltip_request = self.window.next_frame.tooltip_requests.last().cloned()?;
1455 let tooltip_request = tooltip_request.unwrap();
1456 let mut element = tooltip_request.tooltip.view.clone().into_any();
1457 let mouse_position = tooltip_request.tooltip.mouse_position;
1458 let tooltip_size = element.layout_as_root(AvailableSpace::min_size(), self);
1459
1460 let mut tooltip_bounds = Bounds::new(mouse_position + point(px(1.), px(1.)), tooltip_size);
1461 let window_bounds = Bounds {
1462 origin: Point::default(),
1463 size: self.viewport_size(),
1464 };
1465
1466 if tooltip_bounds.right() > window_bounds.right() {
1467 let new_x = mouse_position.x - tooltip_bounds.size.width - px(1.);
1468 if new_x >= Pixels::ZERO {
1469 tooltip_bounds.origin.x = new_x;
1470 } else {
1471 tooltip_bounds.origin.x = cmp::max(
1472 Pixels::ZERO,
1473 tooltip_bounds.origin.x - tooltip_bounds.right() - window_bounds.right(),
1474 );
1475 }
1476 }
1477
1478 if tooltip_bounds.bottom() > window_bounds.bottom() {
1479 let new_y = mouse_position.y - tooltip_bounds.size.height - px(1.);
1480 if new_y >= Pixels::ZERO {
1481 tooltip_bounds.origin.y = new_y;
1482 } else {
1483 tooltip_bounds.origin.y = cmp::max(
1484 Pixels::ZERO,
1485 tooltip_bounds.origin.y - tooltip_bounds.bottom() - window_bounds.bottom(),
1486 );
1487 }
1488 }
1489
1490 self.with_absolute_element_offset(tooltip_bounds.origin, |cx| element.prepaint(cx));
1491
1492 self.window.tooltip_bounds = Some(TooltipBounds {
1493 id: tooltip_request.id,
1494 bounds: tooltip_bounds,
1495 });
1496 Some(element)
1497 }
1498
1499 fn prepaint_deferred_draws(&mut self, deferred_draw_indices: &[usize]) {
1500 assert_eq!(self.window.element_id_stack.len(), 0);
1501
1502 let mut deferred_draws = mem::take(&mut self.window.next_frame.deferred_draws);
1503 for deferred_draw_ix in deferred_draw_indices {
1504 let deferred_draw = &mut deferred_draws[*deferred_draw_ix];
1505 self.window
1506 .element_id_stack
1507 .clone_from(&deferred_draw.element_id_stack);
1508 self.window
1509 .text_style_stack
1510 .clone_from(&deferred_draw.text_style_stack);
1511 self.window
1512 .next_frame
1513 .dispatch_tree
1514 .set_active_node(deferred_draw.parent_node);
1515
1516 let prepaint_start = self.prepaint_index();
1517 if let Some(element) = deferred_draw.element.as_mut() {
1518 self.with_absolute_element_offset(deferred_draw.absolute_offset, |cx| {
1519 element.prepaint(cx)
1520 });
1521 } else {
1522 self.reuse_prepaint(deferred_draw.prepaint_range.clone());
1523 }
1524 let prepaint_end = self.prepaint_index();
1525 deferred_draw.prepaint_range = prepaint_start..prepaint_end;
1526 }
1527 assert_eq!(
1528 self.window.next_frame.deferred_draws.len(),
1529 0,
1530 "cannot call defer_draw during deferred drawing"
1531 );
1532 self.window.next_frame.deferred_draws = deferred_draws;
1533 self.window.element_id_stack.clear();
1534 self.window.text_style_stack.clear();
1535 }
1536
1537 fn paint_deferred_draws(&mut self, deferred_draw_indices: &[usize]) {
1538 assert_eq!(self.window.element_id_stack.len(), 0);
1539
1540 let mut deferred_draws = mem::take(&mut self.window.next_frame.deferred_draws);
1541 for deferred_draw_ix in deferred_draw_indices {
1542 let mut deferred_draw = &mut deferred_draws[*deferred_draw_ix];
1543 self.window
1544 .element_id_stack
1545 .clone_from(&deferred_draw.element_id_stack);
1546 self.window
1547 .next_frame
1548 .dispatch_tree
1549 .set_active_node(deferred_draw.parent_node);
1550
1551 let paint_start = self.paint_index();
1552 if let Some(element) = deferred_draw.element.as_mut() {
1553 element.paint(self);
1554 } else {
1555 self.reuse_paint(deferred_draw.paint_range.clone());
1556 }
1557 let paint_end = self.paint_index();
1558 deferred_draw.paint_range = paint_start..paint_end;
1559 }
1560 self.window.next_frame.deferred_draws = deferred_draws;
1561 self.window.element_id_stack.clear();
1562 }
1563
1564 pub(crate) fn prepaint_index(&self) -> PrepaintStateIndex {
1565 PrepaintStateIndex {
1566 hitboxes_index: self.window.next_frame.hitboxes.len(),
1567 tooltips_index: self.window.next_frame.tooltip_requests.len(),
1568 deferred_draws_index: self.window.next_frame.deferred_draws.len(),
1569 dispatch_tree_index: self.window.next_frame.dispatch_tree.len(),
1570 accessed_element_states_index: self.window.next_frame.accessed_element_states.len(),
1571 line_layout_index: self.window.text_system.layout_index(),
1572 }
1573 }
1574
1575 pub(crate) fn reuse_prepaint(&mut self, range: Range<PrepaintStateIndex>) {
1576 let window = &mut self.window;
1577 window.next_frame.hitboxes.extend(
1578 window.rendered_frame.hitboxes[range.start.hitboxes_index..range.end.hitboxes_index]
1579 .iter()
1580 .cloned(),
1581 );
1582 window.next_frame.tooltip_requests.extend(
1583 window.rendered_frame.tooltip_requests
1584 [range.start.tooltips_index..range.end.tooltips_index]
1585 .iter_mut()
1586 .map(|request| request.take()),
1587 );
1588 window.next_frame.accessed_element_states.extend(
1589 window.rendered_frame.accessed_element_states[range.start.accessed_element_states_index
1590 ..range.end.accessed_element_states_index]
1591 .iter()
1592 .map(|(id, type_id)| (GlobalElementId(id.0.clone()), *type_id)),
1593 );
1594 window
1595 .text_system
1596 .reuse_layouts(range.start.line_layout_index..range.end.line_layout_index);
1597
1598 let reused_subtree = window.next_frame.dispatch_tree.reuse_subtree(
1599 range.start.dispatch_tree_index..range.end.dispatch_tree_index,
1600 &mut window.rendered_frame.dispatch_tree,
1601 );
1602 window.next_frame.deferred_draws.extend(
1603 window.rendered_frame.deferred_draws
1604 [range.start.deferred_draws_index..range.end.deferred_draws_index]
1605 .iter()
1606 .map(|deferred_draw| DeferredDraw {
1607 parent_node: reused_subtree.refresh_node_id(deferred_draw.parent_node),
1608 element_id_stack: deferred_draw.element_id_stack.clone(),
1609 text_style_stack: deferred_draw.text_style_stack.clone(),
1610 priority: deferred_draw.priority,
1611 element: None,
1612 absolute_offset: deferred_draw.absolute_offset,
1613 prepaint_range: deferred_draw.prepaint_range.clone(),
1614 paint_range: deferred_draw.paint_range.clone(),
1615 }),
1616 );
1617 }
1618
1619 pub(crate) fn paint_index(&self) -> PaintIndex {
1620 PaintIndex {
1621 scene_index: self.window.next_frame.scene.len(),
1622 mouse_listeners_index: self.window.next_frame.mouse_listeners.len(),
1623 input_handlers_index: self.window.next_frame.input_handlers.len(),
1624 cursor_styles_index: self.window.next_frame.cursor_styles.len(),
1625 accessed_element_states_index: self.window.next_frame.accessed_element_states.len(),
1626 line_layout_index: self.window.text_system.layout_index(),
1627 }
1628 }
1629
1630 pub(crate) fn reuse_paint(&mut self, range: Range<PaintIndex>) {
1631 let window = &mut self.window;
1632
1633 window.next_frame.cursor_styles.extend(
1634 window.rendered_frame.cursor_styles
1635 [range.start.cursor_styles_index..range.end.cursor_styles_index]
1636 .iter()
1637 .cloned(),
1638 );
1639 window.next_frame.input_handlers.extend(
1640 window.rendered_frame.input_handlers
1641 [range.start.input_handlers_index..range.end.input_handlers_index]
1642 .iter_mut()
1643 .map(|handler| handler.take()),
1644 );
1645 window.next_frame.mouse_listeners.extend(
1646 window.rendered_frame.mouse_listeners
1647 [range.start.mouse_listeners_index..range.end.mouse_listeners_index]
1648 .iter_mut()
1649 .map(|listener| listener.take()),
1650 );
1651 window.next_frame.accessed_element_states.extend(
1652 window.rendered_frame.accessed_element_states[range.start.accessed_element_states_index
1653 ..range.end.accessed_element_states_index]
1654 .iter()
1655 .map(|(id, type_id)| (GlobalElementId(id.0.clone()), *type_id)),
1656 );
1657 window
1658 .text_system
1659 .reuse_layouts(range.start.line_layout_index..range.end.line_layout_index);
1660 window.next_frame.scene.replay(
1661 range.start.scene_index..range.end.scene_index,
1662 &window.rendered_frame.scene,
1663 );
1664 }
1665
1666 /// Push a text style onto the stack, and call a function with that style active.
1667 /// Use [`AppContext::text_style`] to get the current, combined text style. This method
1668 /// should only be called as part of element drawing.
1669 pub fn with_text_style<F, R>(&mut self, style: Option<TextStyleRefinement>, f: F) -> R
1670 where
1671 F: FnOnce(&mut Self) -> R,
1672 {
1673 debug_assert!(
1674 matches!(
1675 self.window.draw_phase,
1676 DrawPhase::Prepaint | DrawPhase::Paint
1677 ),
1678 "this method can only be called during request_layout, prepaint, or paint"
1679 );
1680 if let Some(style) = style {
1681 self.window.text_style_stack.push(style);
1682 let result = f(self);
1683 self.window.text_style_stack.pop();
1684 result
1685 } else {
1686 f(self)
1687 }
1688 }
1689
1690 /// Updates the cursor style at the platform level. This method should only be called
1691 /// during the prepaint phase of element drawing.
1692 pub fn set_cursor_style(&mut self, style: CursorStyle, hitbox: &Hitbox) {
1693 debug_assert_eq!(
1694 self.window.draw_phase,
1695 DrawPhase::Paint,
1696 "this method can only be called during paint"
1697 );
1698 self.window
1699 .next_frame
1700 .cursor_styles
1701 .push(CursorStyleRequest {
1702 hitbox_id: hitbox.id,
1703 style,
1704 });
1705 }
1706
1707 /// Sets a tooltip to be rendered for the upcoming frame. This method should only be called
1708 /// during the paint phase of element drawing.
1709 pub fn set_tooltip(&mut self, tooltip: AnyTooltip) -> TooltipId {
1710 debug_assert_eq!(
1711 self.window.draw_phase,
1712 DrawPhase::Prepaint,
1713 "this method can only be called during prepaint"
1714 );
1715 let id = TooltipId(post_inc(&mut self.window.next_tooltip_id.0));
1716 self.window
1717 .next_frame
1718 .tooltip_requests
1719 .push(Some(TooltipRequest { id, tooltip }));
1720 id
1721 }
1722
1723 /// Invoke the given function with the given content mask after intersecting it
1724 /// with the current mask. This method should only be called during element drawing.
1725 pub fn with_content_mask<R>(
1726 &mut self,
1727 mask: Option<ContentMask<Pixels>>,
1728 f: impl FnOnce(&mut Self) -> R,
1729 ) -> R {
1730 debug_assert!(
1731 matches!(
1732 self.window.draw_phase,
1733 DrawPhase::Prepaint | DrawPhase::Paint
1734 ),
1735 "this method can only be called during request_layout, prepaint, or paint"
1736 );
1737 if let Some(mask) = mask {
1738 let mask = mask.intersect(&self.content_mask());
1739 self.window_mut().content_mask_stack.push(mask);
1740 let result = f(self);
1741 self.window_mut().content_mask_stack.pop();
1742 result
1743 } else {
1744 f(self)
1745 }
1746 }
1747
1748 /// Updates the global element offset relative to the current offset. This is used to implement
1749 /// scrolling. This method should only be called during the prepaint phase of element drawing.
1750 pub fn with_element_offset<R>(
1751 &mut self,
1752 offset: Point<Pixels>,
1753 f: impl FnOnce(&mut Self) -> R,
1754 ) -> R {
1755 debug_assert_eq!(
1756 self.window.draw_phase,
1757 DrawPhase::Prepaint,
1758 "this method can only be called during request_layout, or prepaint"
1759 );
1760
1761 if offset.is_zero() {
1762 return f(self);
1763 };
1764
1765 let abs_offset = self.element_offset() + offset;
1766 self.with_absolute_element_offset(abs_offset, f)
1767 }
1768
1769 /// Updates the global element offset based on the given offset. This is used to implement
1770 /// drag handles and other manual painting of elements. This method should only be called during
1771 /// the prepaint phase of element drawing.
1772 pub fn with_absolute_element_offset<R>(
1773 &mut self,
1774 offset: Point<Pixels>,
1775 f: impl FnOnce(&mut Self) -> R,
1776 ) -> R {
1777 debug_assert_eq!(
1778 self.window.draw_phase,
1779 DrawPhase::Prepaint,
1780 "this method can only be called during request_layout, or prepaint"
1781 );
1782 self.window_mut().element_offset_stack.push(offset);
1783 let result = f(self);
1784 self.window_mut().element_offset_stack.pop();
1785 result
1786 }
1787
1788 /// Perform prepaint on child elements in a "retryable" manner, so that any side effects
1789 /// of prepaints can be discarded before prepainting again. This is used to support autoscroll
1790 /// where we need to prepaint children to detect the autoscroll bounds, then adjust the
1791 /// element offset and prepaint again. See [`List`] for an example. This method should only be
1792 /// called during the prepaint phase of element drawing.
1793 pub fn transact<T, U>(&mut self, f: impl FnOnce(&mut Self) -> Result<T, U>) -> Result<T, U> {
1794 debug_assert_eq!(
1795 self.window.draw_phase,
1796 DrawPhase::Prepaint,
1797 "this method can only be called during prepaint"
1798 );
1799 let index = self.prepaint_index();
1800 let result = f(self);
1801 if result.is_err() {
1802 self.window
1803 .next_frame
1804 .hitboxes
1805 .truncate(index.hitboxes_index);
1806 self.window
1807 .next_frame
1808 .tooltip_requests
1809 .truncate(index.tooltips_index);
1810 self.window
1811 .next_frame
1812 .deferred_draws
1813 .truncate(index.deferred_draws_index);
1814 self.window
1815 .next_frame
1816 .dispatch_tree
1817 .truncate(index.dispatch_tree_index);
1818 self.window
1819 .next_frame
1820 .accessed_element_states
1821 .truncate(index.accessed_element_states_index);
1822 self.window
1823 .text_system
1824 .truncate_layouts(index.line_layout_index);
1825 }
1826 result
1827 }
1828
1829 /// When you call this method during [`prepaint`], containing elements will attempt to
1830 /// scroll to cause the specified bounds to become visible. When they decide to autoscroll, they will call
1831 /// [`prepaint`] again with a new set of bounds. See [`List`] for an example of an element
1832 /// that supports this method being called on the elements it contains. This method should only be
1833 /// called during the prepaint phase of element drawing.
1834 pub fn request_autoscroll(&mut self, bounds: Bounds<Pixels>) {
1835 debug_assert_eq!(
1836 self.window.draw_phase,
1837 DrawPhase::Prepaint,
1838 "this method can only be called during prepaint"
1839 );
1840 self.window.requested_autoscroll = Some(bounds);
1841 }
1842
1843 /// This method can be called from a containing element such as [`List`] to support the autoscroll behavior
1844 /// described in [`request_autoscroll`].
1845 pub fn take_autoscroll(&mut self) -> Option<Bounds<Pixels>> {
1846 debug_assert_eq!(
1847 self.window.draw_phase,
1848 DrawPhase::Prepaint,
1849 "this method can only be called during prepaint"
1850 );
1851 self.window.requested_autoscroll.take()
1852 }
1853
1854 /// Remove an asset from GPUI's cache
1855 pub fn remove_cached_asset<A: Asset + 'static>(
1856 &mut self,
1857 source: &A::Source,
1858 ) -> Option<A::Output> {
1859 self.asset_cache.remove::<A>(source)
1860 }
1861
1862 /// Asynchronously load an asset, if the asset hasn't finished loading this will return None.
1863 /// Your view will be re-drawn once the asset has finished loading.
1864 ///
1865 /// Note that the multiple calls to this method will only result in one `Asset::load` call.
1866 /// The results of that call will be cached, and returned on subsequent uses of this API.
1867 ///
1868 /// Use [Self::remove_cached_asset] to reload your asset.
1869 pub fn use_cached_asset<A: Asset + 'static>(
1870 &mut self,
1871 source: &A::Source,
1872 ) -> Option<A::Output> {
1873 self.asset_cache.get::<A>(source).or_else(|| {
1874 if let Some(asset) = self.use_asset::<A>(source) {
1875 self.asset_cache
1876 .insert::<A>(source.to_owned(), asset.clone());
1877 Some(asset)
1878 } else {
1879 None
1880 }
1881 })
1882 }
1883
1884 /// Asynchronously load an asset, if the asset hasn't finished loading this will return None.
1885 /// Your view will be re-drawn once the asset has finished loading.
1886 ///
1887 /// Note that the multiple calls to this method will only result in one `Asset::load` call at a
1888 /// time.
1889 ///
1890 /// This asset will not be cached by default, see [Self::use_cached_asset]
1891 pub fn use_asset<A: Asset + 'static>(&mut self, source: &A::Source) -> Option<A::Output> {
1892 let asset_id = (TypeId::of::<A>(), hash(source));
1893 let mut is_first = false;
1894 let task = self
1895 .loading_assets
1896 .remove(&asset_id)
1897 .map(|boxed_task| *boxed_task.downcast::<Shared<Task<A::Output>>>().unwrap())
1898 .unwrap_or_else(|| {
1899 is_first = true;
1900 let future = A::load(source.clone(), self);
1901 let task = self.background_executor().spawn(future).shared();
1902 task
1903 });
1904
1905 task.clone().now_or_never().or_else(|| {
1906 if is_first {
1907 let parent_id = self.parent_view_id();
1908 self.spawn({
1909 let task = task.clone();
1910 |mut cx| async move {
1911 task.await;
1912
1913 cx.on_next_frame(move |cx| {
1914 if let Some(parent_id) = parent_id {
1915 cx.notify(parent_id)
1916 } else {
1917 cx.refresh()
1918 }
1919 });
1920 }
1921 })
1922 .detach();
1923 }
1924
1925 self.loading_assets.insert(asset_id, Box::new(task));
1926
1927 None
1928 })
1929 }
1930
1931 /// Obtain the current element offset. This method should only be called during the
1932 /// prepaint phase of element drawing.
1933 pub fn element_offset(&self) -> Point<Pixels> {
1934 debug_assert_eq!(
1935 self.window.draw_phase,
1936 DrawPhase::Prepaint,
1937 "this method can only be called during prepaint"
1938 );
1939 self.window()
1940 .element_offset_stack
1941 .last()
1942 .copied()
1943 .unwrap_or_default()
1944 }
1945
1946 /// Obtain the current content mask. This method should only be called during element drawing.
1947 pub fn content_mask(&self) -> ContentMask<Pixels> {
1948 debug_assert!(
1949 matches!(
1950 self.window.draw_phase,
1951 DrawPhase::Prepaint | DrawPhase::Paint
1952 ),
1953 "this method can only be called during prepaint, or paint"
1954 );
1955 self.window()
1956 .content_mask_stack
1957 .last()
1958 .cloned()
1959 .unwrap_or_else(|| ContentMask {
1960 bounds: Bounds {
1961 origin: Point::default(),
1962 size: self.window().viewport_size,
1963 },
1964 })
1965 }
1966
1967 /// Provide elements in the called function with a new namespace in which their identiers must be unique.
1968 /// This can be used within a custom element to distinguish multiple sets of child elements.
1969 pub fn with_element_namespace<R>(
1970 &mut self,
1971 element_id: impl Into<ElementId>,
1972 f: impl FnOnce(&mut Self) -> R,
1973 ) -> R {
1974 self.window.element_id_stack.push(element_id.into());
1975 let result = f(self);
1976 self.window.element_id_stack.pop();
1977 result
1978 }
1979
1980 /// Updates or initializes state for an element with the given id that lives across multiple
1981 /// frames. If an element with this ID existed in the rendered frame, its state will be passed
1982 /// to the given closure. The state returned by the closure will be stored so it can be referenced
1983 /// when drawing the next frame. This method should only be called as part of element drawing.
1984 pub fn with_element_state<S, R>(
1985 &mut self,
1986 global_id: &GlobalElementId,
1987 f: impl FnOnce(Option<S>, &mut Self) -> (R, S),
1988 ) -> R
1989 where
1990 S: 'static,
1991 {
1992 debug_assert!(
1993 matches!(
1994 self.window.draw_phase,
1995 DrawPhase::Prepaint | DrawPhase::Paint
1996 ),
1997 "this method can only be called during request_layout, prepaint, or paint"
1998 );
1999
2000 let key = (GlobalElementId(global_id.0.clone()), TypeId::of::<S>());
2001 self.window
2002 .next_frame
2003 .accessed_element_states
2004 .push((GlobalElementId(key.0.clone()), TypeId::of::<S>()));
2005
2006 if let Some(any) = self
2007 .window
2008 .next_frame
2009 .element_states
2010 .remove(&key)
2011 .or_else(|| self.window.rendered_frame.element_states.remove(&key))
2012 {
2013 let ElementStateBox {
2014 inner,
2015 #[cfg(debug_assertions)]
2016 type_name,
2017 } = any;
2018 // Using the extra inner option to avoid needing to reallocate a new box.
2019 let mut state_box = inner
2020 .downcast::<Option<S>>()
2021 .map_err(|_| {
2022 #[cfg(debug_assertions)]
2023 {
2024 anyhow::anyhow!(
2025 "invalid element state type for id, requested {:?}, actual: {:?}",
2026 std::any::type_name::<S>(),
2027 type_name
2028 )
2029 }
2030
2031 #[cfg(not(debug_assertions))]
2032 {
2033 anyhow::anyhow!(
2034 "invalid element state type for id, requested {:?}",
2035 std::any::type_name::<S>(),
2036 )
2037 }
2038 })
2039 .unwrap();
2040
2041 let state = state_box.take().expect(
2042 "reentrant call to with_element_state for the same state type and element id",
2043 );
2044 let (result, state) = f(Some(state), self);
2045 state_box.replace(state);
2046 self.window.next_frame.element_states.insert(
2047 key,
2048 ElementStateBox {
2049 inner: state_box,
2050 #[cfg(debug_assertions)]
2051 type_name,
2052 },
2053 );
2054 result
2055 } else {
2056 let (result, state) = f(None, self);
2057 self.window.next_frame.element_states.insert(
2058 key,
2059 ElementStateBox {
2060 inner: Box::new(Some(state)),
2061 #[cfg(debug_assertions)]
2062 type_name: std::any::type_name::<S>(),
2063 },
2064 );
2065 result
2066 }
2067 }
2068
2069 /// A variant of `with_element_state` that allows the element's id to be optional. This is a convenience
2070 /// method for elements where the element id may or may not be assigned. Prefer using `with_element_state`
2071 /// when the element is guaranteed to have an id.
2072 pub fn with_optional_element_state<S, R>(
2073 &mut self,
2074 global_id: Option<&GlobalElementId>,
2075 f: impl FnOnce(Option<Option<S>>, &mut Self) -> (R, Option<S>),
2076 ) -> R
2077 where
2078 S: 'static,
2079 {
2080 debug_assert!(
2081 matches!(
2082 self.window.draw_phase,
2083 DrawPhase::Prepaint | DrawPhase::Paint
2084 ),
2085 "this method can only be called during request_layout, prepaint, or paint"
2086 );
2087
2088 if let Some(global_id) = global_id {
2089 self.with_element_state(global_id, |state, cx| {
2090 let (result, state) = f(Some(state), cx);
2091 let state =
2092 state.expect("you must return some state when you pass some element id");
2093 (result, state)
2094 })
2095 } else {
2096 let (result, state) = f(None, self);
2097 debug_assert!(
2098 state.is_none(),
2099 "you must not return an element state when passing None for the global id"
2100 );
2101 result
2102 }
2103 }
2104
2105 /// Defers the drawing of the given element, scheduling it to be painted on top of the currently-drawn tree
2106 /// at a later time. The `priority` parameter determines the drawing order relative to other deferred elements,
2107 /// with higher values being drawn on top.
2108 ///
2109 /// This method should only be called as part of the prepaint phase of element drawing.
2110 pub fn defer_draw(
2111 &mut self,
2112 element: AnyElement,
2113 absolute_offset: Point<Pixels>,
2114 priority: usize,
2115 ) {
2116 let window = &mut self.window;
2117 debug_assert_eq!(
2118 window.draw_phase,
2119 DrawPhase::Prepaint,
2120 "this method can only be called during request_layout or prepaint"
2121 );
2122 let parent_node = window.next_frame.dispatch_tree.active_node_id().unwrap();
2123 window.next_frame.deferred_draws.push(DeferredDraw {
2124 parent_node,
2125 element_id_stack: window.element_id_stack.clone(),
2126 text_style_stack: window.text_style_stack.clone(),
2127 priority,
2128 element: Some(element),
2129 absolute_offset,
2130 prepaint_range: PrepaintStateIndex::default()..PrepaintStateIndex::default(),
2131 paint_range: PaintIndex::default()..PaintIndex::default(),
2132 });
2133 }
2134
2135 /// Creates a new painting layer for the specified bounds. A "layer" is a batch
2136 /// of geometry that are non-overlapping and have the same draw order. This is typically used
2137 /// for performance reasons.
2138 ///
2139 /// This method should only be called as part of the paint phase of element drawing.
2140 pub fn paint_layer<R>(&mut self, bounds: Bounds<Pixels>, f: impl FnOnce(&mut Self) -> R) -> R {
2141 debug_assert_eq!(
2142 self.window.draw_phase,
2143 DrawPhase::Paint,
2144 "this method can only be called during paint"
2145 );
2146
2147 let scale_factor = self.scale_factor();
2148 let content_mask = self.content_mask();
2149 let clipped_bounds = bounds.intersect(&content_mask.bounds);
2150 if !clipped_bounds.is_empty() {
2151 self.window
2152 .next_frame
2153 .scene
2154 .push_layer(clipped_bounds.scale(scale_factor));
2155 }
2156
2157 let result = f(self);
2158
2159 if !clipped_bounds.is_empty() {
2160 self.window.next_frame.scene.pop_layer();
2161 }
2162
2163 result
2164 }
2165
2166 /// Paint one or more drop shadows into the scene for the next frame at the current z-index.
2167 ///
2168 /// This method should only be called as part of the paint phase of element drawing.
2169 pub fn paint_shadows(
2170 &mut self,
2171 bounds: Bounds<Pixels>,
2172 corner_radii: Corners<Pixels>,
2173 shadows: &[BoxShadow],
2174 ) {
2175 debug_assert_eq!(
2176 self.window.draw_phase,
2177 DrawPhase::Paint,
2178 "this method can only be called during paint"
2179 );
2180
2181 let scale_factor = self.scale_factor();
2182 let content_mask = self.content_mask();
2183 for shadow in shadows {
2184 let mut shadow_bounds = bounds;
2185 shadow_bounds.origin += shadow.offset;
2186 shadow_bounds.dilate(shadow.spread_radius);
2187 self.window.next_frame.scene.insert_primitive(Shadow {
2188 order: 0,
2189 blur_radius: shadow.blur_radius.scale(scale_factor),
2190 bounds: shadow_bounds.scale(scale_factor),
2191 content_mask: content_mask.scale(scale_factor),
2192 corner_radii: corner_radii.scale(scale_factor),
2193 color: shadow.color,
2194 });
2195 }
2196 }
2197
2198 /// Paint one or more quads into the scene for the next frame at the current stacking context.
2199 /// Quads are colored rectangular regions with an optional background, border, and corner radius.
2200 /// see [`fill`](crate::fill), [`outline`](crate::outline), and [`quad`](crate::quad) to construct this type.
2201 ///
2202 /// This method should only be called as part of the paint phase of element drawing.
2203 pub fn paint_quad(&mut self, quad: PaintQuad) {
2204 debug_assert_eq!(
2205 self.window.draw_phase,
2206 DrawPhase::Paint,
2207 "this method can only be called during paint"
2208 );
2209
2210 let scale_factor = self.scale_factor();
2211 let content_mask = self.content_mask();
2212 self.window.next_frame.scene.insert_primitive(Quad {
2213 order: 0,
2214 pad: 0,
2215 bounds: quad.bounds.scale(scale_factor),
2216 content_mask: content_mask.scale(scale_factor),
2217 background: quad.background,
2218 border_color: quad.border_color,
2219 corner_radii: quad.corner_radii.scale(scale_factor),
2220 border_widths: quad.border_widths.scale(scale_factor),
2221 });
2222 }
2223
2224 /// Paint the given `Path` into the scene for the next frame at the current z-index.
2225 ///
2226 /// This method should only be called as part of the paint phase of element drawing.
2227 pub fn paint_path(&mut self, mut path: Path<Pixels>, color: impl Into<Hsla>) {
2228 debug_assert_eq!(
2229 self.window.draw_phase,
2230 DrawPhase::Paint,
2231 "this method can only be called during paint"
2232 );
2233
2234 let scale_factor = self.scale_factor();
2235 let content_mask = self.content_mask();
2236 path.content_mask = content_mask;
2237 path.color = color.into();
2238 self.window
2239 .next_frame
2240 .scene
2241 .insert_primitive(path.scale(scale_factor));
2242 }
2243
2244 /// Paint an underline into the scene for the next frame at the current z-index.
2245 ///
2246 /// This method should only be called as part of the paint phase of element drawing.
2247 pub fn paint_underline(
2248 &mut self,
2249 origin: Point<Pixels>,
2250 width: Pixels,
2251 style: &UnderlineStyle,
2252 ) {
2253 debug_assert_eq!(
2254 self.window.draw_phase,
2255 DrawPhase::Paint,
2256 "this method can only be called during paint"
2257 );
2258
2259 let scale_factor = self.scale_factor();
2260 let height = if style.wavy {
2261 style.thickness * 3.
2262 } else {
2263 style.thickness
2264 };
2265 let bounds = Bounds {
2266 origin,
2267 size: size(width, height),
2268 };
2269 let content_mask = self.content_mask();
2270
2271 self.window.next_frame.scene.insert_primitive(Underline {
2272 order: 0,
2273 pad: 0,
2274 bounds: bounds.scale(scale_factor),
2275 content_mask: content_mask.scale(scale_factor),
2276 color: style.color.unwrap_or_default(),
2277 thickness: style.thickness.scale(scale_factor),
2278 wavy: style.wavy,
2279 });
2280 }
2281
2282 /// Paint a strikethrough into the scene for the next frame at the current z-index.
2283 ///
2284 /// This method should only be called as part of the paint phase of element drawing.
2285 pub fn paint_strikethrough(
2286 &mut self,
2287 origin: Point<Pixels>,
2288 width: Pixels,
2289 style: &StrikethroughStyle,
2290 ) {
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 height = style.thickness;
2299 let bounds = Bounds {
2300 origin,
2301 size: size(width, height),
2302 };
2303 let content_mask = self.content_mask();
2304
2305 self.window.next_frame.scene.insert_primitive(Underline {
2306 order: 0,
2307 pad: 0,
2308 bounds: bounds.scale(scale_factor),
2309 content_mask: content_mask.scale(scale_factor),
2310 thickness: style.thickness.scale(scale_factor),
2311 color: style.color.unwrap_or_default(),
2312 wavy: false,
2313 });
2314 }
2315
2316 /// Paints a monochrome (non-emoji) glyph into the scene for the next frame at the current z-index.
2317 ///
2318 /// The y component of the origin is the baseline of the glyph.
2319 /// You should generally prefer to use the [`ShapedLine::paint`](crate::ShapedLine::paint) or
2320 /// [`WrappedLine::paint`](crate::WrappedLine::paint) methods in the [`TextSystem`](crate::TextSystem).
2321 /// This method is only useful if you need to paint a single glyph that has already been shaped.
2322 ///
2323 /// This method should only be called as part of the paint phase of element drawing.
2324 pub fn paint_glyph(
2325 &mut self,
2326 origin: Point<Pixels>,
2327 font_id: FontId,
2328 glyph_id: GlyphId,
2329 font_size: Pixels,
2330 color: Hsla,
2331 ) -> Result<()> {
2332 debug_assert_eq!(
2333 self.window.draw_phase,
2334 DrawPhase::Paint,
2335 "this method can only be called during paint"
2336 );
2337
2338 let scale_factor = self.scale_factor();
2339 let glyph_origin = origin.scale(scale_factor);
2340 let subpixel_variant = Point {
2341 x: (glyph_origin.x.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
2342 y: (glyph_origin.y.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
2343 };
2344 let params = RenderGlyphParams {
2345 font_id,
2346 glyph_id,
2347 font_size,
2348 subpixel_variant,
2349 scale_factor,
2350 is_emoji: false,
2351 };
2352
2353 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
2354 if !raster_bounds.is_zero() {
2355 let tile = self
2356 .window
2357 .sprite_atlas
2358 .get_or_insert_with(¶ms.clone().into(), &mut || {
2359 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
2360 Ok(Some((size, Cow::Owned(bytes))))
2361 })?
2362 .expect("Callback above only errors or returns Some");
2363 let bounds = Bounds {
2364 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
2365 size: tile.bounds.size.map(Into::into),
2366 };
2367 let content_mask = self.content_mask().scale(scale_factor);
2368 self.window
2369 .next_frame
2370 .scene
2371 .insert_primitive(MonochromeSprite {
2372 order: 0,
2373 pad: 0,
2374 bounds,
2375 content_mask,
2376 color,
2377 tile,
2378 transformation: TransformationMatrix::unit(),
2379 });
2380 }
2381 Ok(())
2382 }
2383
2384 /// Paints an emoji glyph into the scene for the next frame at the current z-index.
2385 ///
2386 /// The y component of the origin is the baseline of the glyph.
2387 /// You should generally prefer to use the [`ShapedLine::paint`](crate::ShapedLine::paint) or
2388 /// [`WrappedLine::paint`](crate::WrappedLine::paint) methods in the [`TextSystem`](crate::TextSystem).
2389 /// This method is only useful if you need to paint a single emoji that has already been shaped.
2390 ///
2391 /// This method should only be called as part of the paint phase of element drawing.
2392 pub fn paint_emoji(
2393 &mut self,
2394 origin: Point<Pixels>,
2395 font_id: FontId,
2396 glyph_id: GlyphId,
2397 font_size: Pixels,
2398 ) -> Result<()> {
2399 debug_assert_eq!(
2400 self.window.draw_phase,
2401 DrawPhase::Paint,
2402 "this method can only be called during paint"
2403 );
2404
2405 let scale_factor = self.scale_factor();
2406 let glyph_origin = origin.scale(scale_factor);
2407 let params = RenderGlyphParams {
2408 font_id,
2409 glyph_id,
2410 font_size,
2411 // We don't render emojis with subpixel variants.
2412 subpixel_variant: Default::default(),
2413 scale_factor,
2414 is_emoji: true,
2415 };
2416
2417 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
2418 if !raster_bounds.is_zero() {
2419 let tile = self
2420 .window
2421 .sprite_atlas
2422 .get_or_insert_with(¶ms.clone().into(), &mut || {
2423 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
2424 Ok(Some((size, Cow::Owned(bytes))))
2425 })?
2426 .expect("Callback above only errors or returns Some");
2427
2428 let bounds = Bounds {
2429 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
2430 size: tile.bounds.size.map(Into::into),
2431 };
2432 let content_mask = self.content_mask().scale(scale_factor);
2433
2434 self.window
2435 .next_frame
2436 .scene
2437 .insert_primitive(PolychromeSprite {
2438 order: 0,
2439 grayscale: false,
2440 bounds,
2441 corner_radii: Default::default(),
2442 content_mask,
2443 tile,
2444 });
2445 }
2446 Ok(())
2447 }
2448
2449 /// Paint a monochrome SVG into the scene for the next frame at the current stacking context.
2450 ///
2451 /// This method should only be called as part of the paint phase of element drawing.
2452 pub fn paint_svg(
2453 &mut self,
2454 bounds: Bounds<Pixels>,
2455 path: SharedString,
2456 transformation: TransformationMatrix,
2457 color: Hsla,
2458 ) -> Result<()> {
2459 debug_assert_eq!(
2460 self.window.draw_phase,
2461 DrawPhase::Paint,
2462 "this method can only be called during paint"
2463 );
2464
2465 let scale_factor = self.scale_factor();
2466 let bounds = bounds.scale(scale_factor);
2467 // Render the SVG at twice the size to get a higher quality result.
2468 let params = RenderSvgParams {
2469 path,
2470 size: bounds
2471 .size
2472 .map(|pixels| DevicePixels::from((pixels.0 * 2.).ceil() as i32)),
2473 };
2474
2475 let Some(tile) =
2476 self.window
2477 .sprite_atlas
2478 .get_or_insert_with(¶ms.clone().into(), &mut || {
2479 let Some(bytes) = self.svg_renderer.render(¶ms)? else {
2480 return Ok(None);
2481 };
2482 Ok(Some((params.size, Cow::Owned(bytes))))
2483 })?
2484 else {
2485 return Ok(());
2486 };
2487 let content_mask = self.content_mask().scale(scale_factor);
2488
2489 self.window
2490 .next_frame
2491 .scene
2492 .insert_primitive(MonochromeSprite {
2493 order: 0,
2494 pad: 0,
2495 bounds,
2496 content_mask,
2497 color,
2498 tile,
2499 transformation,
2500 });
2501
2502 Ok(())
2503 }
2504
2505 /// Paint an image into the scene for the next frame at the current z-index.
2506 ///
2507 /// This method should only be called as part of the paint phase of element drawing.
2508 pub fn paint_image(
2509 &mut self,
2510 bounds: Bounds<Pixels>,
2511 corner_radii: Corners<Pixels>,
2512 data: Arc<ImageData>,
2513 grayscale: bool,
2514 ) -> Result<()> {
2515 debug_assert_eq!(
2516 self.window.draw_phase,
2517 DrawPhase::Paint,
2518 "this method can only be called during paint"
2519 );
2520
2521 let scale_factor = self.scale_factor();
2522 let bounds = bounds.scale(scale_factor);
2523 let params = RenderImageParams { image_id: data.id };
2524
2525 let tile = self
2526 .window
2527 .sprite_atlas
2528 .get_or_insert_with(¶ms.clone().into(), &mut || {
2529 Ok(Some((data.size(), Cow::Borrowed(data.as_bytes()))))
2530 })?
2531 .expect("Callback above only returns Some");
2532 let content_mask = self.content_mask().scale(scale_factor);
2533 let corner_radii = corner_radii.scale(scale_factor);
2534
2535 self.window
2536 .next_frame
2537 .scene
2538 .insert_primitive(PolychromeSprite {
2539 order: 0,
2540 grayscale,
2541 bounds,
2542 content_mask,
2543 corner_radii,
2544 tile,
2545 });
2546 Ok(())
2547 }
2548
2549 /// Paint a surface into the scene for the next frame at the current z-index.
2550 ///
2551 /// This method should only be called as part of the paint phase of element drawing.
2552 #[cfg(target_os = "macos")]
2553 pub fn paint_surface(&mut self, bounds: Bounds<Pixels>, image_buffer: CVImageBuffer) {
2554 debug_assert_eq!(
2555 self.window.draw_phase,
2556 DrawPhase::Paint,
2557 "this method can only be called during paint"
2558 );
2559
2560 let scale_factor = self.scale_factor();
2561 let bounds = bounds.scale(scale_factor);
2562 let content_mask = self.content_mask().scale(scale_factor);
2563 self.window
2564 .next_frame
2565 .scene
2566 .insert_primitive(crate::Surface {
2567 order: 0,
2568 bounds,
2569 content_mask,
2570 image_buffer,
2571 });
2572 }
2573
2574 #[must_use]
2575 /// Add a node to the layout tree for the current frame. Takes the `Style` of the element for which
2576 /// layout is being requested, along with the layout ids of any children. This method is called during
2577 /// calls to the [`Element::request_layout`] trait method and enables any element to participate in layout.
2578 ///
2579 /// This method should only be called as part of the request_layout or prepaint phase of element drawing.
2580 pub fn request_layout(
2581 &mut self,
2582 style: Style,
2583 children: impl IntoIterator<Item = LayoutId>,
2584 ) -> LayoutId {
2585 debug_assert_eq!(
2586 self.window.draw_phase,
2587 DrawPhase::Prepaint,
2588 "this method can only be called during request_layout, or prepaint"
2589 );
2590
2591 self.app.layout_id_buffer.clear();
2592 self.app.layout_id_buffer.extend(children);
2593 let rem_size = self.rem_size();
2594
2595 self.window.layout_engine.as_mut().unwrap().request_layout(
2596 style,
2597 rem_size,
2598 &self.app.layout_id_buffer,
2599 )
2600 }
2601
2602 /// Add a node to the layout tree for the current frame. Instead of taking a `Style` and children,
2603 /// this variant takes a function that is invoked during layout so you can use arbitrary logic to
2604 /// determine the element's size. One place this is used internally is when measuring text.
2605 ///
2606 /// The given closure is invoked at layout time with the known dimensions and available space and
2607 /// returns a `Size`.
2608 ///
2609 /// This method should only be called as part of the request_layout or prepaint phase of element drawing.
2610 pub fn request_measured_layout<
2611 F: FnMut(Size<Option<Pixels>>, Size<AvailableSpace>, &mut WindowContext) -> Size<Pixels>
2612 + 'static,
2613 >(
2614 &mut self,
2615 style: Style,
2616 measure: F,
2617 ) -> LayoutId {
2618 debug_assert_eq!(
2619 self.window.draw_phase,
2620 DrawPhase::Prepaint,
2621 "this method can only be called during request_layout, or prepaint"
2622 );
2623
2624 let rem_size = self.rem_size();
2625 self.window
2626 .layout_engine
2627 .as_mut()
2628 .unwrap()
2629 .request_measured_layout(style, rem_size, measure)
2630 }
2631
2632 /// Compute the layout for the given id within the given available space.
2633 /// This method is called for its side effect, typically by the framework prior to painting.
2634 /// After calling it, you can request the bounds of the given layout node id or any descendant.
2635 ///
2636 /// This method should only be called as part of the prepaint phase of element drawing.
2637 pub fn compute_layout(&mut self, layout_id: LayoutId, available_space: Size<AvailableSpace>) {
2638 debug_assert_eq!(
2639 self.window.draw_phase,
2640 DrawPhase::Prepaint,
2641 "this method can only be called during request_layout, or prepaint"
2642 );
2643
2644 let mut layout_engine = self.window.layout_engine.take().unwrap();
2645 layout_engine.compute_layout(layout_id, available_space, self);
2646 self.window.layout_engine = Some(layout_engine);
2647 }
2648
2649 /// Obtain the bounds computed for the given LayoutId relative to the window. This method will usually be invoked by
2650 /// GPUI itself automatically in order to pass your element its `Bounds` automatically.
2651 ///
2652 /// This method should only be called as part of element drawing.
2653 pub fn layout_bounds(&mut self, layout_id: LayoutId) -> Bounds<Pixels> {
2654 debug_assert_eq!(
2655 self.window.draw_phase,
2656 DrawPhase::Prepaint,
2657 "this method can only be called during request_layout, prepaint, or paint"
2658 );
2659
2660 let mut bounds = self
2661 .window
2662 .layout_engine
2663 .as_mut()
2664 .unwrap()
2665 .layout_bounds(layout_id)
2666 .map(Into::into);
2667 bounds.origin += self.element_offset();
2668 bounds
2669 }
2670
2671 /// This method should be called during `prepaint`. You can use
2672 /// the returned [Hitbox] during `paint` or in an event handler
2673 /// to determine whether the inserted hitbox was the topmost.
2674 ///
2675 /// This method should only be called as part of the prepaint phase of element drawing.
2676 pub fn insert_hitbox(&mut self, bounds: Bounds<Pixels>, opaque: bool) -> Hitbox {
2677 debug_assert_eq!(
2678 self.window.draw_phase,
2679 DrawPhase::Prepaint,
2680 "this method can only be called during prepaint"
2681 );
2682
2683 let content_mask = self.content_mask();
2684 let window = &mut self.window;
2685 let id = window.next_hitbox_id;
2686 window.next_hitbox_id.0 += 1;
2687 let hitbox = Hitbox {
2688 id,
2689 bounds,
2690 content_mask,
2691 opaque,
2692 };
2693 window.next_frame.hitboxes.push(hitbox.clone());
2694 hitbox
2695 }
2696
2697 /// Sets the key context for the current element. This context will be used to translate
2698 /// keybindings into actions.
2699 ///
2700 /// This method should only be called as part of the paint phase of element drawing.
2701 pub fn set_key_context(&mut self, context: KeyContext) {
2702 debug_assert_eq!(
2703 self.window.draw_phase,
2704 DrawPhase::Paint,
2705 "this method can only be called during paint"
2706 );
2707 self.window
2708 .next_frame
2709 .dispatch_tree
2710 .set_key_context(context);
2711 }
2712
2713 /// Sets the focus handle for the current element. This handle will be used to manage focus state
2714 /// and keyboard event dispatch for the element.
2715 ///
2716 /// This method should only be called as part of the paint phase of element drawing.
2717 pub fn set_focus_handle(&mut self, focus_handle: &FocusHandle) {
2718 debug_assert_eq!(
2719 self.window.draw_phase,
2720 DrawPhase::Paint,
2721 "this method can only be called during paint"
2722 );
2723 self.window
2724 .next_frame
2725 .dispatch_tree
2726 .set_focus_id(focus_handle.id);
2727 }
2728
2729 /// Sets the view id for the current element, which will be used to manage view caching.
2730 ///
2731 /// This method should only be called as part of element prepaint. We plan on removing this
2732 /// method eventually when we solve some issues that require us to construct editor elements
2733 /// directly instead of always using editors via views.
2734 pub fn set_view_id(&mut self, view_id: EntityId) {
2735 debug_assert_eq!(
2736 self.window.draw_phase,
2737 DrawPhase::Prepaint,
2738 "this method can only be called during prepaint"
2739 );
2740 self.window.next_frame.dispatch_tree.set_view_id(view_id);
2741 }
2742
2743 /// Get the last view id for the current element
2744 pub fn parent_view_id(&mut self) -> Option<EntityId> {
2745 self.window.next_frame.dispatch_tree.parent_view_id()
2746 }
2747
2748 /// Sets an input handler, such as [`ElementInputHandler`][element_input_handler], which interfaces with the
2749 /// platform to receive textual input with proper integration with concerns such
2750 /// as IME interactions. This handler will be active for the upcoming frame until the following frame is
2751 /// rendered.
2752 ///
2753 /// This method should only be called as part of the paint phase of element drawing.
2754 ///
2755 /// [element_input_handler]: crate::ElementInputHandler
2756 pub fn handle_input(&mut self, focus_handle: &FocusHandle, input_handler: impl InputHandler) {
2757 debug_assert_eq!(
2758 self.window.draw_phase,
2759 DrawPhase::Paint,
2760 "this method can only be called during paint"
2761 );
2762
2763 if focus_handle.is_focused(self) {
2764 let cx = self.to_async();
2765 self.window
2766 .next_frame
2767 .input_handlers
2768 .push(Some(PlatformInputHandler::new(cx, Box::new(input_handler))));
2769 }
2770 }
2771
2772 /// Register a mouse event listener on the window for the next frame. The type of event
2773 /// is determined by the first parameter of the given listener. When the next frame is rendered
2774 /// the listener will be cleared.
2775 ///
2776 /// This method should only be called as part of the paint phase of element drawing.
2777 pub fn on_mouse_event<Event: MouseEvent>(
2778 &mut self,
2779 mut handler: impl FnMut(&Event, DispatchPhase, &mut WindowContext) + 'static,
2780 ) {
2781 debug_assert_eq!(
2782 self.window.draw_phase,
2783 DrawPhase::Paint,
2784 "this method can only be called during paint"
2785 );
2786
2787 self.window.next_frame.mouse_listeners.push(Some(Box::new(
2788 move |event: &dyn Any, phase: DispatchPhase, cx: &mut WindowContext<'_>| {
2789 if let Some(event) = event.downcast_ref() {
2790 handler(event, phase, cx)
2791 }
2792 },
2793 )));
2794 }
2795
2796 /// Register a key event listener on the window for the next frame. The type of event
2797 /// is determined by the first parameter of the given listener. When the next frame is rendered
2798 /// the listener will be cleared.
2799 ///
2800 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
2801 /// a specific need to register a global listener.
2802 ///
2803 /// This method should only be called as part of the paint phase of element drawing.
2804 pub fn on_key_event<Event: KeyEvent>(
2805 &mut self,
2806 listener: impl Fn(&Event, DispatchPhase, &mut WindowContext) + 'static,
2807 ) {
2808 debug_assert_eq!(
2809 self.window.draw_phase,
2810 DrawPhase::Paint,
2811 "this method can only be called during paint"
2812 );
2813
2814 self.window.next_frame.dispatch_tree.on_key_event(Rc::new(
2815 move |event: &dyn Any, phase, cx: &mut WindowContext<'_>| {
2816 if let Some(event) = event.downcast_ref::<Event>() {
2817 listener(event, phase, cx)
2818 }
2819 },
2820 ));
2821 }
2822
2823 /// Register a modifiers changed event listener on the window for the next frame.
2824 ///
2825 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
2826 /// a specific need to register a global listener.
2827 ///
2828 /// This method should only be called as part of the paint phase of element drawing.
2829 pub fn on_modifiers_changed(
2830 &mut self,
2831 listener: impl Fn(&ModifiersChangedEvent, &mut WindowContext) + 'static,
2832 ) {
2833 debug_assert_eq!(
2834 self.window.draw_phase,
2835 DrawPhase::Paint,
2836 "this method can only be called during paint"
2837 );
2838
2839 self.window
2840 .next_frame
2841 .dispatch_tree
2842 .on_modifiers_changed(Rc::new(
2843 move |event: &ModifiersChangedEvent, cx: &mut WindowContext<'_>| {
2844 listener(event, cx)
2845 },
2846 ));
2847 }
2848
2849 fn reset_cursor_style(&self) {
2850 // Set the cursor only if we're the active window.
2851 if self.is_window_active() {
2852 let style = self
2853 .window
2854 .rendered_frame
2855 .cursor_styles
2856 .iter()
2857 .rev()
2858 .find(|request| request.hitbox_id.is_hovered(self))
2859 .map(|request| request.style)
2860 .unwrap_or(CursorStyle::Arrow);
2861 self.platform.set_cursor_style(style);
2862 }
2863 }
2864
2865 /// Dispatch a given keystroke as though the user had typed it.
2866 /// You can create a keystroke with Keystroke::parse("").
2867 pub fn dispatch_keystroke(&mut self, keystroke: Keystroke) -> bool {
2868 let keystroke = keystroke.with_simulated_ime();
2869 let result = self.dispatch_event(PlatformInput::KeyDown(KeyDownEvent {
2870 keystroke: keystroke.clone(),
2871 is_held: false,
2872 }));
2873 if !result.propagate {
2874 return true;
2875 }
2876
2877 if let Some(input) = keystroke.ime_key {
2878 if let Some(mut input_handler) = self.window.platform_window.take_input_handler() {
2879 input_handler.dispatch_input(&input, self);
2880 self.window.platform_window.set_input_handler(input_handler);
2881 return true;
2882 }
2883 }
2884
2885 false
2886 }
2887
2888 /// Represent this action as a key binding string, to display in the UI.
2889 pub fn keystroke_text_for(&self, action: &dyn Action) -> String {
2890 self.bindings_for_action(action)
2891 .into_iter()
2892 .next()
2893 .map(|binding| {
2894 binding
2895 .keystrokes()
2896 .iter()
2897 .map(ToString::to_string)
2898 .collect::<Vec<_>>()
2899 .join(" ")
2900 })
2901 .unwrap_or_else(|| action.name().to_string())
2902 }
2903
2904 /// Dispatch a mouse or keyboard event on the window.
2905 #[profiling::function]
2906 pub fn dispatch_event(&mut self, event: PlatformInput) -> DispatchEventResult {
2907 self.window.last_input_timestamp.set(Instant::now());
2908 // Handlers may set this to false by calling `stop_propagation`.
2909 self.app.propagate_event = true;
2910 // Handlers may set this to true by calling `prevent_default`.
2911 self.window.default_prevented = false;
2912
2913 let event = match event {
2914 // Track the mouse position with our own state, since accessing the platform
2915 // API for the mouse position can only occur on the main thread.
2916 PlatformInput::MouseMove(mouse_move) => {
2917 self.window.mouse_position = mouse_move.position;
2918 self.window.modifiers = mouse_move.modifiers;
2919 PlatformInput::MouseMove(mouse_move)
2920 }
2921 PlatformInput::MouseDown(mouse_down) => {
2922 self.window.mouse_position = mouse_down.position;
2923 self.window.modifiers = mouse_down.modifiers;
2924 PlatformInput::MouseDown(mouse_down)
2925 }
2926 PlatformInput::MouseUp(mouse_up) => {
2927 self.window.mouse_position = mouse_up.position;
2928 self.window.modifiers = mouse_up.modifiers;
2929 PlatformInput::MouseUp(mouse_up)
2930 }
2931 PlatformInput::MouseExited(mouse_exited) => {
2932 self.window.modifiers = mouse_exited.modifiers;
2933 PlatformInput::MouseExited(mouse_exited)
2934 }
2935 PlatformInput::ModifiersChanged(modifiers_changed) => {
2936 self.window.modifiers = modifiers_changed.modifiers;
2937 PlatformInput::ModifiersChanged(modifiers_changed)
2938 }
2939 PlatformInput::ScrollWheel(scroll_wheel) => {
2940 self.window.mouse_position = scroll_wheel.position;
2941 self.window.modifiers = scroll_wheel.modifiers;
2942 PlatformInput::ScrollWheel(scroll_wheel)
2943 }
2944 // Translate dragging and dropping of external files from the operating system
2945 // to internal drag and drop events.
2946 PlatformInput::FileDrop(file_drop) => match file_drop {
2947 FileDropEvent::Entered { position, paths } => {
2948 self.window.mouse_position = position;
2949 if self.active_drag.is_none() {
2950 self.active_drag = Some(AnyDrag {
2951 value: Box::new(paths.clone()),
2952 view: self.new_view(|_| paths).into(),
2953 cursor_offset: position,
2954 });
2955 }
2956 PlatformInput::MouseMove(MouseMoveEvent {
2957 position,
2958 pressed_button: Some(MouseButton::Left),
2959 modifiers: Modifiers::default(),
2960 })
2961 }
2962 FileDropEvent::Pending { position } => {
2963 self.window.mouse_position = position;
2964 PlatformInput::MouseMove(MouseMoveEvent {
2965 position,
2966 pressed_button: Some(MouseButton::Left),
2967 modifiers: Modifiers::default(),
2968 })
2969 }
2970 FileDropEvent::Submit { position } => {
2971 self.activate(true);
2972 self.window.mouse_position = position;
2973 PlatformInput::MouseUp(MouseUpEvent {
2974 button: MouseButton::Left,
2975 position,
2976 modifiers: Modifiers::default(),
2977 click_count: 1,
2978 })
2979 }
2980 FileDropEvent::Exited => {
2981 self.active_drag.take();
2982 PlatformInput::FileDrop(FileDropEvent::Exited)
2983 }
2984 },
2985 PlatformInput::KeyDown(_) | PlatformInput::KeyUp(_) => event,
2986 };
2987
2988 if let Some(any_mouse_event) = event.mouse_event() {
2989 self.dispatch_mouse_event(any_mouse_event);
2990 } else if let Some(any_key_event) = event.keyboard_event() {
2991 self.dispatch_key_event(any_key_event);
2992 }
2993
2994 DispatchEventResult {
2995 propagate: self.app.propagate_event,
2996 default_prevented: self.window.default_prevented,
2997 }
2998 }
2999
3000 fn dispatch_mouse_event(&mut self, event: &dyn Any) {
3001 let hit_test = self.window.rendered_frame.hit_test(self.mouse_position());
3002 if hit_test != self.window.mouse_hit_test {
3003 self.window.mouse_hit_test = hit_test;
3004 self.reset_cursor_style();
3005 }
3006
3007 let mut mouse_listeners = mem::take(&mut self.window.rendered_frame.mouse_listeners);
3008
3009 // Capture phase, events bubble from back to front. Handlers for this phase are used for
3010 // special purposes, such as detecting events outside of a given Bounds.
3011 for listener in &mut mouse_listeners {
3012 let listener = listener.as_mut().unwrap();
3013 listener(event, DispatchPhase::Capture, self);
3014 if !self.app.propagate_event {
3015 break;
3016 }
3017 }
3018
3019 // Bubble phase, where most normal handlers do their work.
3020 if self.app.propagate_event {
3021 for listener in mouse_listeners.iter_mut().rev() {
3022 let listener = listener.as_mut().unwrap();
3023 listener(event, DispatchPhase::Bubble, self);
3024 if !self.app.propagate_event {
3025 break;
3026 }
3027 }
3028 }
3029
3030 self.window.rendered_frame.mouse_listeners = mouse_listeners;
3031
3032 if self.has_active_drag() {
3033 if event.is::<MouseMoveEvent>() {
3034 // If this was a mouse move event, redraw the window so that the
3035 // active drag can follow the mouse cursor.
3036 self.refresh();
3037 } else if event.is::<MouseUpEvent>() {
3038 // If this was a mouse up event, cancel the active drag and redraw
3039 // the window.
3040 self.active_drag = None;
3041 self.refresh();
3042 }
3043 }
3044 }
3045
3046 fn dispatch_key_event(&mut self, event: &dyn Any) {
3047 if self.window.dirty.get() {
3048 self.draw();
3049 }
3050
3051 let node_id = self
3052 .window
3053 .focus
3054 .and_then(|focus_id| {
3055 self.window
3056 .rendered_frame
3057 .dispatch_tree
3058 .focusable_node_id(focus_id)
3059 })
3060 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3061
3062 let dispatch_path = self
3063 .window
3064 .rendered_frame
3065 .dispatch_tree
3066 .dispatch_path(node_id);
3067
3068 if let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() {
3069 let KeymatchResult { bindings, pending } = self
3070 .window
3071 .rendered_frame
3072 .dispatch_tree
3073 .dispatch_key(&key_down_event.keystroke, &dispatch_path);
3074
3075 if pending {
3076 let mut currently_pending = self.window.pending_input.take().unwrap_or_default();
3077 if currently_pending.focus.is_some() && currently_pending.focus != self.window.focus
3078 {
3079 currently_pending = PendingInput::default();
3080 }
3081 currently_pending.focus = self.window.focus;
3082 currently_pending
3083 .keystrokes
3084 .push(key_down_event.keystroke.clone());
3085 for binding in bindings {
3086 currently_pending.bindings.push(binding);
3087 }
3088
3089 currently_pending.timer = Some(self.spawn(|mut cx| async move {
3090 cx.background_executor.timer(Duration::from_secs(1)).await;
3091 cx.update(move |cx| {
3092 cx.clear_pending_keystrokes();
3093 let Some(currently_pending) = cx.window.pending_input.take() else {
3094 return;
3095 };
3096 cx.replay_pending_input(currently_pending)
3097 })
3098 .log_err();
3099 }));
3100
3101 self.window.pending_input = Some(currently_pending);
3102
3103 self.propagate_event = false;
3104 return;
3105 } else if let Some(currently_pending) = self.window.pending_input.take() {
3106 if bindings
3107 .iter()
3108 .all(|binding| !currently_pending.used_by_binding(binding))
3109 {
3110 self.replay_pending_input(currently_pending)
3111 }
3112 }
3113
3114 if !bindings.is_empty() {
3115 self.clear_pending_keystrokes();
3116 }
3117
3118 self.propagate_event = true;
3119 for binding in bindings {
3120 self.dispatch_action_on_node(node_id, binding.action.as_ref());
3121 if !self.propagate_event {
3122 self.dispatch_keystroke_observers(event, Some(binding.action));
3123 return;
3124 }
3125 }
3126 }
3127
3128 self.dispatch_key_down_up_event(event, &dispatch_path);
3129 if !self.propagate_event {
3130 return;
3131 }
3132
3133 self.dispatch_modifiers_changed_event(event, &dispatch_path);
3134 if !self.propagate_event {
3135 return;
3136 }
3137
3138 self.dispatch_keystroke_observers(event, None);
3139 }
3140
3141 fn dispatch_key_down_up_event(
3142 &mut self,
3143 event: &dyn Any,
3144 dispatch_path: &SmallVec<[DispatchNodeId; 32]>,
3145 ) {
3146 // Capture phase
3147 for node_id in dispatch_path {
3148 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3149
3150 for key_listener in node.key_listeners.clone() {
3151 key_listener(event, DispatchPhase::Capture, self);
3152 if !self.propagate_event {
3153 return;
3154 }
3155 }
3156 }
3157
3158 // Bubble phase
3159 for node_id in dispatch_path.iter().rev() {
3160 // Handle low level key events
3161 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3162 for key_listener in node.key_listeners.clone() {
3163 key_listener(event, DispatchPhase::Bubble, self);
3164 if !self.propagate_event {
3165 return;
3166 }
3167 }
3168 }
3169 }
3170
3171 fn dispatch_modifiers_changed_event(
3172 &mut self,
3173 event: &dyn Any,
3174 dispatch_path: &SmallVec<[DispatchNodeId; 32]>,
3175 ) {
3176 let Some(event) = event.downcast_ref::<ModifiersChangedEvent>() else {
3177 return;
3178 };
3179 for node_id in dispatch_path.iter().rev() {
3180 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3181 for listener in node.modifiers_changed_listeners.clone() {
3182 listener(event, self);
3183 if !self.propagate_event {
3184 return;
3185 }
3186 }
3187 }
3188 }
3189
3190 /// Determine whether a potential multi-stroke key binding is in progress on this window.
3191 pub fn has_pending_keystrokes(&self) -> bool {
3192 self.window
3193 .rendered_frame
3194 .dispatch_tree
3195 .has_pending_keystrokes()
3196 }
3197
3198 fn replay_pending_input(&mut self, currently_pending: PendingInput) {
3199 let node_id = self
3200 .window
3201 .focus
3202 .and_then(|focus_id| {
3203 self.window
3204 .rendered_frame
3205 .dispatch_tree
3206 .focusable_node_id(focus_id)
3207 })
3208 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3209
3210 if self.window.focus != currently_pending.focus {
3211 return;
3212 }
3213
3214 let input = currently_pending.input();
3215
3216 self.propagate_event = true;
3217 for binding in currently_pending.bindings {
3218 self.dispatch_action_on_node(node_id, binding.action.as_ref());
3219 if !self.propagate_event {
3220 return;
3221 }
3222 }
3223
3224 let dispatch_path = self
3225 .window
3226 .rendered_frame
3227 .dispatch_tree
3228 .dispatch_path(node_id);
3229
3230 for keystroke in currently_pending.keystrokes {
3231 let event = KeyDownEvent {
3232 keystroke,
3233 is_held: false,
3234 };
3235
3236 self.dispatch_key_down_up_event(&event, &dispatch_path);
3237 if !self.propagate_event {
3238 return;
3239 }
3240 }
3241
3242 if !input.is_empty() {
3243 if let Some(mut input_handler) = self.window.platform_window.take_input_handler() {
3244 input_handler.dispatch_input(&input, self);
3245 self.window.platform_window.set_input_handler(input_handler)
3246 }
3247 }
3248 }
3249
3250 fn dispatch_action_on_node(&mut self, node_id: DispatchNodeId, action: &dyn Action) {
3251 let dispatch_path = self
3252 .window
3253 .rendered_frame
3254 .dispatch_tree
3255 .dispatch_path(node_id);
3256
3257 // Capture phase for global actions.
3258 self.propagate_event = true;
3259 if let Some(mut global_listeners) = self
3260 .global_action_listeners
3261 .remove(&action.as_any().type_id())
3262 {
3263 for listener in &global_listeners {
3264 listener(action.as_any(), DispatchPhase::Capture, self);
3265 if !self.propagate_event {
3266 break;
3267 }
3268 }
3269
3270 global_listeners.extend(
3271 self.global_action_listeners
3272 .remove(&action.as_any().type_id())
3273 .unwrap_or_default(),
3274 );
3275
3276 self.global_action_listeners
3277 .insert(action.as_any().type_id(), global_listeners);
3278 }
3279
3280 if !self.propagate_event {
3281 return;
3282 }
3283
3284 // Capture phase for window actions.
3285 for node_id in &dispatch_path {
3286 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3287 for DispatchActionListener {
3288 action_type,
3289 listener,
3290 } in node.action_listeners.clone()
3291 {
3292 let any_action = action.as_any();
3293 if action_type == any_action.type_id() {
3294 listener(any_action, DispatchPhase::Capture, self);
3295
3296 if !self.propagate_event {
3297 return;
3298 }
3299 }
3300 }
3301 }
3302
3303 // Bubble phase for window actions.
3304 for node_id in dispatch_path.iter().rev() {
3305 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3306 for DispatchActionListener {
3307 action_type,
3308 listener,
3309 } in node.action_listeners.clone()
3310 {
3311 let any_action = action.as_any();
3312 if action_type == any_action.type_id() {
3313 self.propagate_event = false; // Actions stop propagation by default during the bubble phase
3314 listener(any_action, DispatchPhase::Bubble, self);
3315
3316 if !self.propagate_event {
3317 return;
3318 }
3319 }
3320 }
3321 }
3322
3323 // Bubble phase for global actions.
3324 if let Some(mut global_listeners) = self
3325 .global_action_listeners
3326 .remove(&action.as_any().type_id())
3327 {
3328 for listener in global_listeners.iter().rev() {
3329 self.propagate_event = false; // Actions stop propagation by default during the bubble phase
3330
3331 listener(action.as_any(), DispatchPhase::Bubble, self);
3332 if !self.propagate_event {
3333 break;
3334 }
3335 }
3336
3337 global_listeners.extend(
3338 self.global_action_listeners
3339 .remove(&action.as_any().type_id())
3340 .unwrap_or_default(),
3341 );
3342
3343 self.global_action_listeners
3344 .insert(action.as_any().type_id(), global_listeners);
3345 }
3346 }
3347
3348 /// Register the given handler to be invoked whenever the global of the given type
3349 /// is updated.
3350 pub fn observe_global<G: Global>(
3351 &mut self,
3352 f: impl Fn(&mut WindowContext<'_>) + 'static,
3353 ) -> Subscription {
3354 let window_handle = self.window.handle;
3355 let (subscription, activate) = self.global_observers.insert(
3356 TypeId::of::<G>(),
3357 Box::new(move |cx| window_handle.update(cx, |_, cx| f(cx)).is_ok()),
3358 );
3359 self.app.defer(move |_| activate());
3360 subscription
3361 }
3362
3363 /// Focus the current window and bring it to the foreground at the platform level.
3364 pub fn activate_window(&self) {
3365 self.window.platform_window.activate();
3366 }
3367
3368 /// Minimize the current window at the platform level.
3369 pub fn minimize_window(&self) {
3370 self.window.platform_window.minimize();
3371 }
3372
3373 /// Toggle full screen status on the current window at the platform level.
3374 pub fn toggle_fullscreen(&self) {
3375 self.window.platform_window.toggle_fullscreen();
3376 }
3377
3378 /// Present a platform dialog.
3379 /// The provided message will be presented, along with buttons for each answer.
3380 /// When a button is clicked, the returned Receiver will receive the index of the clicked button.
3381 pub fn prompt(
3382 &mut self,
3383 level: PromptLevel,
3384 message: &str,
3385 detail: Option<&str>,
3386 answers: &[&str],
3387 ) -> oneshot::Receiver<usize> {
3388 let prompt_builder = self.app.prompt_builder.take();
3389 let Some(prompt_builder) = prompt_builder else {
3390 unreachable!("Re-entrant window prompting is not supported by GPUI");
3391 };
3392
3393 let receiver = match &prompt_builder {
3394 PromptBuilder::Default => self
3395 .window
3396 .platform_window
3397 .prompt(level, message, detail, answers)
3398 .unwrap_or_else(|| {
3399 self.build_custom_prompt(&prompt_builder, level, message, detail, answers)
3400 }),
3401 PromptBuilder::Custom(_) => {
3402 self.build_custom_prompt(&prompt_builder, level, message, detail, answers)
3403 }
3404 };
3405
3406 self.app.prompt_builder = Some(prompt_builder);
3407
3408 receiver
3409 }
3410
3411 fn build_custom_prompt(
3412 &mut self,
3413 prompt_builder: &PromptBuilder,
3414 level: PromptLevel,
3415 message: &str,
3416 detail: Option<&str>,
3417 answers: &[&str],
3418 ) -> oneshot::Receiver<usize> {
3419 let (sender, receiver) = oneshot::channel();
3420 let handle = PromptHandle::new(sender);
3421 let handle = (prompt_builder)(level, message, detail, answers, handle, self);
3422 self.window.prompt = Some(handle);
3423 receiver
3424 }
3425
3426 /// Returns all available actions for the focused element.
3427 pub fn available_actions(&self) -> Vec<Box<dyn Action>> {
3428 let node_id = self
3429 .window
3430 .focus
3431 .and_then(|focus_id| {
3432 self.window
3433 .rendered_frame
3434 .dispatch_tree
3435 .focusable_node_id(focus_id)
3436 })
3437 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3438
3439 let mut actions = self
3440 .window
3441 .rendered_frame
3442 .dispatch_tree
3443 .available_actions(node_id);
3444 for action_type in self.global_action_listeners.keys() {
3445 if let Err(ix) = actions.binary_search_by_key(action_type, |a| a.as_any().type_id()) {
3446 let action = self.actions.build_action_type(action_type).ok();
3447 if let Some(action) = action {
3448 actions.insert(ix, action);
3449 }
3450 }
3451 }
3452 actions
3453 }
3454
3455 /// Returns key bindings that invoke the given action on the currently focused element.
3456 pub fn bindings_for_action(&self, action: &dyn Action) -> Vec<KeyBinding> {
3457 self.window
3458 .rendered_frame
3459 .dispatch_tree
3460 .bindings_for_action(
3461 action,
3462 &self.window.rendered_frame.dispatch_tree.context_stack,
3463 )
3464 }
3465
3466 /// Returns any bindings that would invoke the given action on the given focus handle if it were focused.
3467 pub fn bindings_for_action_in(
3468 &self,
3469 action: &dyn Action,
3470 focus_handle: &FocusHandle,
3471 ) -> Vec<KeyBinding> {
3472 let dispatch_tree = &self.window.rendered_frame.dispatch_tree;
3473
3474 let Some(node_id) = dispatch_tree.focusable_node_id(focus_handle.id) else {
3475 return vec![];
3476 };
3477 let context_stack: Vec<_> = dispatch_tree
3478 .dispatch_path(node_id)
3479 .into_iter()
3480 .filter_map(|node_id| dispatch_tree.node(node_id).context.clone())
3481 .collect();
3482 dispatch_tree.bindings_for_action(action, &context_stack)
3483 }
3484
3485 /// Returns a generic event listener that invokes the given listener with the view and context associated with the given view handle.
3486 pub fn listener_for<V: Render, E>(
3487 &self,
3488 view: &View<V>,
3489 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
3490 ) -> impl Fn(&E, &mut WindowContext) + 'static {
3491 let view = view.downgrade();
3492 move |e: &E, cx: &mut WindowContext| {
3493 view.update(cx, |view, cx| f(view, e, cx)).ok();
3494 }
3495 }
3496
3497 /// Returns a generic handler that invokes the given handler with the view and context associated with the given view handle.
3498 pub fn handler_for<V: Render>(
3499 &self,
3500 view: &View<V>,
3501 f: impl Fn(&mut V, &mut ViewContext<V>) + 'static,
3502 ) -> impl Fn(&mut WindowContext) {
3503 let view = view.downgrade();
3504 move |cx: &mut WindowContext| {
3505 view.update(cx, |view, cx| f(view, cx)).ok();
3506 }
3507 }
3508
3509 /// Register a callback that can interrupt the closing of the current window based the returned boolean.
3510 /// If the callback returns false, the window won't be closed.
3511 pub fn on_window_should_close(&mut self, f: impl Fn(&mut WindowContext) -> bool + 'static) {
3512 let mut this = self.to_async();
3513 self.window
3514 .platform_window
3515 .on_should_close(Box::new(move || this.update(|cx| f(cx)).unwrap_or(true)))
3516 }
3517
3518 /// Register an action listener on the window for the next frame. The type of action
3519 /// is determined by the first parameter of the given listener. When the next frame is rendered
3520 /// the listener will be cleared.
3521 ///
3522 /// This is a fairly low-level method, so prefer using action handlers on elements unless you have
3523 /// a specific need to register a global listener.
3524 pub fn on_action(
3525 &mut self,
3526 action_type: TypeId,
3527 listener: impl Fn(&dyn Any, DispatchPhase, &mut WindowContext) + 'static,
3528 ) {
3529 self.window
3530 .next_frame
3531 .dispatch_tree
3532 .on_action(action_type, Rc::new(listener));
3533 }
3534}
3535
3536#[cfg(target_os = "windows")]
3537impl WindowContext<'_> {
3538 /// Returns the raw HWND handle for the window.
3539 pub fn get_raw_handle(&self) -> windows::Win32::Foundation::HWND {
3540 self.window.platform_window.get_raw_handle()
3541 }
3542}
3543
3544impl Context for WindowContext<'_> {
3545 type Result<T> = T;
3546
3547 fn new_model<T>(&mut self, build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T) -> Model<T>
3548 where
3549 T: 'static,
3550 {
3551 let slot = self.app.entities.reserve();
3552 let model = build_model(&mut ModelContext::new(&mut *self.app, slot.downgrade()));
3553 self.entities.insert(slot, model)
3554 }
3555
3556 fn reserve_model<T: 'static>(&mut self) -> Self::Result<crate::Reservation<T>> {
3557 self.app.reserve_model()
3558 }
3559
3560 fn insert_model<T: 'static>(
3561 &mut self,
3562 reservation: crate::Reservation<T>,
3563 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
3564 ) -> Self::Result<Model<T>> {
3565 self.app.insert_model(reservation, build_model)
3566 }
3567
3568 fn update_model<T: 'static, R>(
3569 &mut self,
3570 model: &Model<T>,
3571 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
3572 ) -> R {
3573 let mut entity = self.entities.lease(model);
3574 let result = update(
3575 &mut *entity,
3576 &mut ModelContext::new(&mut *self.app, model.downgrade()),
3577 );
3578 self.entities.end_lease(entity);
3579 result
3580 }
3581
3582 fn read_model<T, R>(
3583 &self,
3584 handle: &Model<T>,
3585 read: impl FnOnce(&T, &AppContext) -> R,
3586 ) -> Self::Result<R>
3587 where
3588 T: 'static,
3589 {
3590 let entity = self.entities.read(handle);
3591 read(entity, &*self.app)
3592 }
3593
3594 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
3595 where
3596 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
3597 {
3598 if window == self.window.handle {
3599 let root_view = self.window.root_view.clone().unwrap();
3600 Ok(update(root_view, self))
3601 } else {
3602 window.update(self.app, update)
3603 }
3604 }
3605
3606 fn read_window<T, R>(
3607 &self,
3608 window: &WindowHandle<T>,
3609 read: impl FnOnce(View<T>, &AppContext) -> R,
3610 ) -> Result<R>
3611 where
3612 T: 'static,
3613 {
3614 if window.any_handle == self.window.handle {
3615 let root_view = self
3616 .window
3617 .root_view
3618 .clone()
3619 .unwrap()
3620 .downcast::<T>()
3621 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
3622 Ok(read(root_view, self))
3623 } else {
3624 self.app.read_window(window, read)
3625 }
3626 }
3627}
3628
3629impl VisualContext for WindowContext<'_> {
3630 fn new_view<V>(
3631 &mut self,
3632 build_view_state: impl FnOnce(&mut ViewContext<'_, V>) -> V,
3633 ) -> Self::Result<View<V>>
3634 where
3635 V: 'static + Render,
3636 {
3637 let slot = self.app.entities.reserve();
3638 let view = View {
3639 model: slot.clone(),
3640 };
3641 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
3642 let entity = build_view_state(&mut cx);
3643 cx.entities.insert(slot, entity);
3644
3645 // Non-generic part to avoid leaking SubscriberSet to invokers of `new_view`.
3646 fn notify_observers(cx: &mut WindowContext, tid: TypeId, view: AnyView) {
3647 cx.new_view_observers.clone().retain(&tid, |observer| {
3648 let any_view = view.clone();
3649 (observer)(any_view, cx);
3650 true
3651 });
3652 }
3653 notify_observers(self, TypeId::of::<V>(), AnyView::from(view.clone()));
3654
3655 view
3656 }
3657
3658 /// Updates the given view. Prefer calling [`View::update`] instead, which calls this method.
3659 fn update_view<T: 'static, R>(
3660 &mut self,
3661 view: &View<T>,
3662 update: impl FnOnce(&mut T, &mut ViewContext<'_, T>) -> R,
3663 ) -> Self::Result<R> {
3664 let mut lease = self.app.entities.lease(&view.model);
3665 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, view);
3666 let result = update(&mut *lease, &mut cx);
3667 cx.app.entities.end_lease(lease);
3668 result
3669 }
3670
3671 fn replace_root_view<V>(
3672 &mut self,
3673 build_view: impl FnOnce(&mut ViewContext<'_, V>) -> V,
3674 ) -> Self::Result<View<V>>
3675 where
3676 V: 'static + Render,
3677 {
3678 let view = self.new_view(build_view);
3679 self.window.root_view = Some(view.clone().into());
3680 self.refresh();
3681 view
3682 }
3683
3684 fn focus_view<V: crate::FocusableView>(&mut self, view: &View<V>) -> Self::Result<()> {
3685 self.update_view(view, |view, cx| {
3686 view.focus_handle(cx).clone().focus(cx);
3687 })
3688 }
3689
3690 fn dismiss_view<V>(&mut self, view: &View<V>) -> Self::Result<()>
3691 where
3692 V: ManagedView,
3693 {
3694 self.update_view(view, |_, cx| cx.emit(DismissEvent))
3695 }
3696}
3697
3698impl<'a> std::ops::Deref for WindowContext<'a> {
3699 type Target = AppContext;
3700
3701 fn deref(&self) -> &Self::Target {
3702 self.app
3703 }
3704}
3705
3706impl<'a> std::ops::DerefMut for WindowContext<'a> {
3707 fn deref_mut(&mut self) -> &mut Self::Target {
3708 self.app
3709 }
3710}
3711
3712impl<'a> Borrow<AppContext> for WindowContext<'a> {
3713 fn borrow(&self) -> &AppContext {
3714 self.app
3715 }
3716}
3717
3718impl<'a> BorrowMut<AppContext> for WindowContext<'a> {
3719 fn borrow_mut(&mut self) -> &mut AppContext {
3720 self.app
3721 }
3722}
3723
3724/// This trait contains functionality that is shared across [`ViewContext`] and [`WindowContext`]
3725pub trait BorrowWindow: BorrowMut<Window> + BorrowMut<AppContext> {
3726 #[doc(hidden)]
3727 fn app_mut(&mut self) -> &mut AppContext {
3728 self.borrow_mut()
3729 }
3730
3731 #[doc(hidden)]
3732 fn app(&self) -> &AppContext {
3733 self.borrow()
3734 }
3735
3736 #[doc(hidden)]
3737 fn window(&self) -> &Window {
3738 self.borrow()
3739 }
3740
3741 #[doc(hidden)]
3742 fn window_mut(&mut self) -> &mut Window {
3743 self.borrow_mut()
3744 }
3745}
3746
3747impl Borrow<Window> for WindowContext<'_> {
3748 fn borrow(&self) -> &Window {
3749 self.window
3750 }
3751}
3752
3753impl BorrowMut<Window> for WindowContext<'_> {
3754 fn borrow_mut(&mut self) -> &mut Window {
3755 self.window
3756 }
3757}
3758
3759impl<T> BorrowWindow for T where T: BorrowMut<AppContext> + BorrowMut<Window> {}
3760
3761/// Provides access to application state that is specialized for a particular [`View`].
3762/// Allows you to interact with focus, emit events, etc.
3763/// ViewContext also derefs to [`WindowContext`], giving you access to all of its methods as well.
3764/// When you call [`View::update`], you're passed a `&mut V` and an `&mut ViewContext<V>`.
3765pub struct ViewContext<'a, V> {
3766 window_cx: WindowContext<'a>,
3767 view: &'a View<V>,
3768}
3769
3770impl<V> Borrow<AppContext> for ViewContext<'_, V> {
3771 fn borrow(&self) -> &AppContext {
3772 &*self.window_cx.app
3773 }
3774}
3775
3776impl<V> BorrowMut<AppContext> for ViewContext<'_, V> {
3777 fn borrow_mut(&mut self) -> &mut AppContext {
3778 &mut *self.window_cx.app
3779 }
3780}
3781
3782impl<V> Borrow<Window> for ViewContext<'_, V> {
3783 fn borrow(&self) -> &Window {
3784 &*self.window_cx.window
3785 }
3786}
3787
3788impl<V> BorrowMut<Window> for ViewContext<'_, V> {
3789 fn borrow_mut(&mut self) -> &mut Window {
3790 &mut *self.window_cx.window
3791 }
3792}
3793
3794impl<'a, V: 'static> ViewContext<'a, V> {
3795 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window, view: &'a View<V>) -> Self {
3796 Self {
3797 window_cx: WindowContext::new(app, window),
3798 view,
3799 }
3800 }
3801
3802 /// Get the entity_id of this view.
3803 pub fn entity_id(&self) -> EntityId {
3804 self.view.entity_id()
3805 }
3806
3807 /// Get the view pointer underlying this context.
3808 pub fn view(&self) -> &View<V> {
3809 self.view
3810 }
3811
3812 /// Get the model underlying this view.
3813 pub fn model(&self) -> &Model<V> {
3814 &self.view.model
3815 }
3816
3817 /// Access the underlying window context.
3818 pub fn window_context(&mut self) -> &mut WindowContext<'a> {
3819 &mut self.window_cx
3820 }
3821
3822 /// Sets a given callback to be run on the next frame.
3823 pub fn on_next_frame(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static)
3824 where
3825 V: 'static,
3826 {
3827 let view = self.view().clone();
3828 self.window_cx.on_next_frame(move |cx| view.update(cx, f));
3829 }
3830
3831 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
3832 /// that are currently on the stack to be returned to the app.
3833 pub fn defer(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static) {
3834 let view = self.view().downgrade();
3835 self.window_cx.defer(move |cx| {
3836 view.update(cx, f).ok();
3837 });
3838 }
3839
3840 /// Observe another model or view for changes to its state, as tracked by [`ModelContext::notify`].
3841 pub fn observe<V2, E>(
3842 &mut self,
3843 entity: &E,
3844 mut on_notify: impl FnMut(&mut V, E, &mut ViewContext<'_, V>) + 'static,
3845 ) -> Subscription
3846 where
3847 V2: 'static,
3848 V: 'static,
3849 E: Entity<V2>,
3850 {
3851 let view = self.view().downgrade();
3852 let entity_id = entity.entity_id();
3853 let entity = entity.downgrade();
3854 let window_handle = self.window.handle;
3855 self.app.new_observer(
3856 entity_id,
3857 Box::new(move |cx| {
3858 window_handle
3859 .update(cx, |_, cx| {
3860 if let Some(handle) = E::upgrade_from(&entity) {
3861 view.update(cx, |this, cx| on_notify(this, handle, cx))
3862 .is_ok()
3863 } else {
3864 false
3865 }
3866 })
3867 .unwrap_or(false)
3868 }),
3869 )
3870 }
3871
3872 /// Subscribe to events emitted by another model or view.
3873 /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
3874 /// 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.
3875 pub fn subscribe<V2, E, Evt>(
3876 &mut self,
3877 entity: &E,
3878 mut on_event: impl FnMut(&mut V, E, &Evt, &mut ViewContext<'_, V>) + 'static,
3879 ) -> Subscription
3880 where
3881 V2: EventEmitter<Evt>,
3882 E: Entity<V2>,
3883 Evt: 'static,
3884 {
3885 let view = self.view().downgrade();
3886 let entity_id = entity.entity_id();
3887 let handle = entity.downgrade();
3888 let window_handle = self.window.handle;
3889 self.app.new_subscription(
3890 entity_id,
3891 (
3892 TypeId::of::<Evt>(),
3893 Box::new(move |event, cx| {
3894 window_handle
3895 .update(cx, |_, cx| {
3896 if let Some(handle) = E::upgrade_from(&handle) {
3897 let event = event.downcast_ref().expect("invalid event type");
3898 view.update(cx, |this, cx| on_event(this, handle, event, cx))
3899 .is_ok()
3900 } else {
3901 false
3902 }
3903 })
3904 .unwrap_or(false)
3905 }),
3906 ),
3907 )
3908 }
3909
3910 /// Register a callback to be invoked when the view is released.
3911 ///
3912 /// The callback receives a handle to the view's window. This handle may be
3913 /// invalid, if the window was closed before the view was released.
3914 pub fn on_release(
3915 &mut self,
3916 on_release: impl FnOnce(&mut V, AnyWindowHandle, &mut AppContext) + 'static,
3917 ) -> Subscription {
3918 let window_handle = self.window.handle;
3919 let (subscription, activate) = self.app.release_listeners.insert(
3920 self.view.model.entity_id,
3921 Box::new(move |this, cx| {
3922 let this = this.downcast_mut().expect("invalid entity type");
3923 on_release(this, window_handle, cx)
3924 }),
3925 );
3926 activate();
3927 subscription
3928 }
3929
3930 /// Register a callback to be invoked when the given Model or View is released.
3931 pub fn observe_release<V2, E>(
3932 &mut self,
3933 entity: &E,
3934 mut on_release: impl FnMut(&mut V, &mut V2, &mut ViewContext<'_, V>) + 'static,
3935 ) -> Subscription
3936 where
3937 V: 'static,
3938 V2: 'static,
3939 E: Entity<V2>,
3940 {
3941 let view = self.view().downgrade();
3942 let entity_id = entity.entity_id();
3943 let window_handle = self.window.handle;
3944 let (subscription, activate) = self.app.release_listeners.insert(
3945 entity_id,
3946 Box::new(move |entity, cx| {
3947 let entity = entity.downcast_mut().expect("invalid entity type");
3948 let _ = window_handle.update(cx, |_, cx| {
3949 view.update(cx, |this, cx| on_release(this, entity, cx))
3950 });
3951 }),
3952 );
3953 activate();
3954 subscription
3955 }
3956
3957 /// Indicate that this view has changed, which will invoke any observers and also mark the window as dirty.
3958 /// If this view or any of its ancestors are *cached*, notifying it will cause it or its ancestors to be redrawn.
3959 pub fn notify(&mut self) {
3960 self.window_cx.notify(self.view.entity_id());
3961 }
3962
3963 /// Register a callback to be invoked when the window is resized.
3964 pub fn observe_window_bounds(
3965 &mut self,
3966 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
3967 ) -> Subscription {
3968 let view = self.view.downgrade();
3969 let (subscription, activate) = self.window.bounds_observers.insert(
3970 (),
3971 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
3972 );
3973 activate();
3974 subscription
3975 }
3976
3977 /// Register a callback to be invoked when the window is activated or deactivated.
3978 pub fn observe_window_activation(
3979 &mut self,
3980 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
3981 ) -> Subscription {
3982 let view = self.view.downgrade();
3983 let (subscription, activate) = self.window.activation_observers.insert(
3984 (),
3985 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
3986 );
3987 activate();
3988 subscription
3989 }
3990
3991 /// Registers a callback to be invoked when the window appearance changes.
3992 pub fn observe_window_appearance(
3993 &mut self,
3994 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
3995 ) -> Subscription {
3996 let view = self.view.downgrade();
3997 let (subscription, activate) = self.window.appearance_observers.insert(
3998 (),
3999 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
4000 );
4001 activate();
4002 subscription
4003 }
4004
4005 /// Register a listener to be called when the given focus handle receives focus.
4006 /// Returns a subscription and persists until the subscription is dropped.
4007 pub fn on_focus(
4008 &mut self,
4009 handle: &FocusHandle,
4010 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4011 ) -> Subscription {
4012 let view = self.view.downgrade();
4013 let focus_id = handle.id;
4014 let (subscription, activate) =
4015 self.window.new_focus_listener(Box::new(move |event, cx| {
4016 view.update(cx, |view, cx| {
4017 if event.previous_focus_path.last() != Some(&focus_id)
4018 && event.current_focus_path.last() == Some(&focus_id)
4019 {
4020 listener(view, cx)
4021 }
4022 })
4023 .is_ok()
4024 }));
4025 self.app.defer(|_| activate());
4026 subscription
4027 }
4028
4029 /// Register a listener to be called when the given focus handle or one of its descendants receives focus.
4030 /// Returns a subscription and persists until the subscription is dropped.
4031 pub fn on_focus_in(
4032 &mut self,
4033 handle: &FocusHandle,
4034 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4035 ) -> Subscription {
4036 let view = self.view.downgrade();
4037 let focus_id = handle.id;
4038 let (subscription, activate) =
4039 self.window.new_focus_listener(Box::new(move |event, cx| {
4040 view.update(cx, |view, cx| {
4041 if !event.previous_focus_path.contains(&focus_id)
4042 && event.current_focus_path.contains(&focus_id)
4043 {
4044 listener(view, cx)
4045 }
4046 })
4047 .is_ok()
4048 }));
4049 self.app.defer(move |_| activate());
4050 subscription
4051 }
4052
4053 /// Register a listener to be called when the given focus handle loses focus.
4054 /// Returns a subscription and persists until the subscription is dropped.
4055 pub fn on_blur(
4056 &mut self,
4057 handle: &FocusHandle,
4058 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4059 ) -> Subscription {
4060 let view = self.view.downgrade();
4061 let focus_id = handle.id;
4062 let (subscription, activate) =
4063 self.window.new_focus_listener(Box::new(move |event, cx| {
4064 view.update(cx, |view, cx| {
4065 if event.previous_focus_path.last() == Some(&focus_id)
4066 && event.current_focus_path.last() != Some(&focus_id)
4067 {
4068 listener(view, cx)
4069 }
4070 })
4071 .is_ok()
4072 }));
4073 self.app.defer(move |_| activate());
4074 subscription
4075 }
4076
4077 /// Register a listener to be called when nothing in the window has focus.
4078 /// This typically happens when the node that was focused is removed from the tree,
4079 /// and this callback lets you chose a default place to restore the users focus.
4080 /// Returns a subscription and persists until the subscription is dropped.
4081 pub fn on_focus_lost(
4082 &mut self,
4083 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4084 ) -> Subscription {
4085 let view = self.view.downgrade();
4086 let (subscription, activate) = self.window.focus_lost_listeners.insert(
4087 (),
4088 Box::new(move |cx| view.update(cx, |view, cx| listener(view, cx)).is_ok()),
4089 );
4090 activate();
4091 subscription
4092 }
4093
4094 /// Register a listener to be called when the given focus handle or one of its descendants loses focus.
4095 /// Returns a subscription and persists until the subscription is dropped.
4096 pub fn on_focus_out(
4097 &mut self,
4098 handle: &FocusHandle,
4099 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4100 ) -> Subscription {
4101 let view = self.view.downgrade();
4102 let focus_id = handle.id;
4103 let (subscription, activate) =
4104 self.window.new_focus_listener(Box::new(move |event, cx| {
4105 view.update(cx, |view, cx| {
4106 if event.previous_focus_path.contains(&focus_id)
4107 && !event.current_focus_path.contains(&focus_id)
4108 {
4109 listener(view, cx)
4110 }
4111 })
4112 .is_ok()
4113 }));
4114 self.app.defer(move |_| activate());
4115 subscription
4116 }
4117
4118 /// Schedule a future to be run asynchronously.
4119 /// The given callback is invoked with a [`WeakView<V>`] to avoid leaking the view for a long-running process.
4120 /// It's also given an [`AsyncWindowContext`], which can be used to access the state of the view across await points.
4121 /// The returned future will be polled on the main thread.
4122 pub fn spawn<Fut, R>(
4123 &mut self,
4124 f: impl FnOnce(WeakView<V>, AsyncWindowContext) -> Fut,
4125 ) -> Task<R>
4126 where
4127 R: 'static,
4128 Fut: Future<Output = R> + 'static,
4129 {
4130 let view = self.view().downgrade();
4131 self.window_cx.spawn(|cx| f(view, cx))
4132 }
4133
4134 /// Register a callback to be invoked when the given global state changes.
4135 pub fn observe_global<G: Global>(
4136 &mut self,
4137 mut f: impl FnMut(&mut V, &mut ViewContext<'_, V>) + 'static,
4138 ) -> Subscription {
4139 let window_handle = self.window.handle;
4140 let view = self.view().downgrade();
4141 let (subscription, activate) = self.global_observers.insert(
4142 TypeId::of::<G>(),
4143 Box::new(move |cx| {
4144 window_handle
4145 .update(cx, |_, cx| view.update(cx, |view, cx| f(view, cx)).is_ok())
4146 .unwrap_or(false)
4147 }),
4148 );
4149 self.app.defer(move |_| activate());
4150 subscription
4151 }
4152
4153 /// Register a callback to be invoked when the given Action type is dispatched to the window.
4154 pub fn on_action(
4155 &mut self,
4156 action_type: TypeId,
4157 listener: impl Fn(&mut V, &dyn Any, DispatchPhase, &mut ViewContext<V>) + 'static,
4158 ) {
4159 let handle = self.view().clone();
4160 self.window_cx
4161 .on_action(action_type, move |action, phase, cx| {
4162 handle.update(cx, |view, cx| {
4163 listener(view, action, phase, cx);
4164 })
4165 });
4166 }
4167
4168 /// Emit an event to be handled any other views that have subscribed via [ViewContext::subscribe].
4169 pub fn emit<Evt>(&mut self, event: Evt)
4170 where
4171 Evt: 'static,
4172 V: EventEmitter<Evt>,
4173 {
4174 let emitter = self.view.model.entity_id;
4175 self.app.push_effect(Effect::Emit {
4176 emitter,
4177 event_type: TypeId::of::<Evt>(),
4178 event: Box::new(event),
4179 });
4180 }
4181
4182 /// Move focus to the current view, assuming it implements [`FocusableView`].
4183 pub fn focus_self(&mut self)
4184 where
4185 V: FocusableView,
4186 {
4187 self.defer(|view, cx| view.focus_handle(cx).focus(cx))
4188 }
4189
4190 /// Convenience method for accessing view state in an event callback.
4191 ///
4192 /// Many GPUI callbacks take the form of `Fn(&E, &mut WindowContext)`,
4193 /// but it's often useful to be able to access view state in these
4194 /// callbacks. This method provides a convenient way to do so.
4195 pub fn listener<E>(
4196 &self,
4197 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
4198 ) -> impl Fn(&E, &mut WindowContext) + 'static {
4199 let view = self.view().downgrade();
4200 move |e: &E, cx: &mut WindowContext| {
4201 view.update(cx, |view, cx| f(view, e, cx)).ok();
4202 }
4203 }
4204}
4205
4206impl<V> Context for ViewContext<'_, V> {
4207 type Result<U> = U;
4208
4209 fn new_model<T: 'static>(
4210 &mut self,
4211 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
4212 ) -> Model<T> {
4213 self.window_cx.new_model(build_model)
4214 }
4215
4216 fn reserve_model<T: 'static>(&mut self) -> Self::Result<crate::Reservation<T>> {
4217 self.window_cx.reserve_model()
4218 }
4219
4220 fn insert_model<T: 'static>(
4221 &mut self,
4222 reservation: crate::Reservation<T>,
4223 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
4224 ) -> Self::Result<Model<T>> {
4225 self.window_cx.insert_model(reservation, build_model)
4226 }
4227
4228 fn update_model<T: 'static, R>(
4229 &mut self,
4230 model: &Model<T>,
4231 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
4232 ) -> R {
4233 self.window_cx.update_model(model, update)
4234 }
4235
4236 fn read_model<T, R>(
4237 &self,
4238 handle: &Model<T>,
4239 read: impl FnOnce(&T, &AppContext) -> R,
4240 ) -> Self::Result<R>
4241 where
4242 T: 'static,
4243 {
4244 self.window_cx.read_model(handle, read)
4245 }
4246
4247 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
4248 where
4249 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
4250 {
4251 self.window_cx.update_window(window, update)
4252 }
4253
4254 fn read_window<T, R>(
4255 &self,
4256 window: &WindowHandle<T>,
4257 read: impl FnOnce(View<T>, &AppContext) -> R,
4258 ) -> Result<R>
4259 where
4260 T: 'static,
4261 {
4262 self.window_cx.read_window(window, read)
4263 }
4264}
4265
4266impl<V: 'static> VisualContext for ViewContext<'_, V> {
4267 fn new_view<W: Render + 'static>(
4268 &mut self,
4269 build_view_state: impl FnOnce(&mut ViewContext<'_, W>) -> W,
4270 ) -> Self::Result<View<W>> {
4271 self.window_cx.new_view(build_view_state)
4272 }
4273
4274 fn update_view<V2: 'static, R>(
4275 &mut self,
4276 view: &View<V2>,
4277 update: impl FnOnce(&mut V2, &mut ViewContext<'_, V2>) -> R,
4278 ) -> Self::Result<R> {
4279 self.window_cx.update_view(view, update)
4280 }
4281
4282 fn replace_root_view<W>(
4283 &mut self,
4284 build_view: impl FnOnce(&mut ViewContext<'_, W>) -> W,
4285 ) -> Self::Result<View<W>>
4286 where
4287 W: 'static + Render,
4288 {
4289 self.window_cx.replace_root_view(build_view)
4290 }
4291
4292 fn focus_view<W: FocusableView>(&mut self, view: &View<W>) -> Self::Result<()> {
4293 self.window_cx.focus_view(view)
4294 }
4295
4296 fn dismiss_view<W: ManagedView>(&mut self, view: &View<W>) -> Self::Result<()> {
4297 self.window_cx.dismiss_view(view)
4298 }
4299}
4300
4301impl<'a, V> std::ops::Deref for ViewContext<'a, V> {
4302 type Target = WindowContext<'a>;
4303
4304 fn deref(&self) -> &Self::Target {
4305 &self.window_cx
4306 }
4307}
4308
4309impl<'a, V> std::ops::DerefMut for ViewContext<'a, V> {
4310 fn deref_mut(&mut self) -> &mut Self::Target {
4311 &mut self.window_cx
4312 }
4313}
4314
4315// #[derive(Clone, Copy, Eq, PartialEq, Hash)]
4316slotmap::new_key_type! {
4317 /// A unique identifier for a window.
4318 pub struct WindowId;
4319}
4320
4321impl WindowId {
4322 /// Converts this window ID to a `u64`.
4323 pub fn as_u64(&self) -> u64 {
4324 self.0.as_ffi()
4325 }
4326}
4327
4328/// A handle to a window with a specific root view type.
4329/// Note that this does not keep the window alive on its own.
4330#[derive(Deref, DerefMut)]
4331pub struct WindowHandle<V> {
4332 #[deref]
4333 #[deref_mut]
4334 pub(crate) any_handle: AnyWindowHandle,
4335 state_type: PhantomData<V>,
4336}
4337
4338impl<V: 'static + Render> WindowHandle<V> {
4339 /// Creates a new handle from a window ID.
4340 /// This does not check if the root type of the window is `V`.
4341 pub fn new(id: WindowId) -> Self {
4342 WindowHandle {
4343 any_handle: AnyWindowHandle {
4344 id,
4345 state_type: TypeId::of::<V>(),
4346 },
4347 state_type: PhantomData,
4348 }
4349 }
4350
4351 /// Get the root view out of this window.
4352 ///
4353 /// This will fail if the window is closed or if the root view's type does not match `V`.
4354 pub fn root<C>(&self, cx: &mut C) -> Result<View<V>>
4355 where
4356 C: Context,
4357 {
4358 Flatten::flatten(cx.update_window(self.any_handle, |root_view, _| {
4359 root_view
4360 .downcast::<V>()
4361 .map_err(|_| anyhow!("the type of the window's root view has changed"))
4362 }))
4363 }
4364
4365 /// Updates the root view of this window.
4366 ///
4367 /// This will fail if the window has been closed or if the root view's type does not match
4368 pub fn update<C, R>(
4369 &self,
4370 cx: &mut C,
4371 update: impl FnOnce(&mut V, &mut ViewContext<'_, V>) -> R,
4372 ) -> Result<R>
4373 where
4374 C: Context,
4375 {
4376 cx.update_window(self.any_handle, |root_view, cx| {
4377 let view = root_view
4378 .downcast::<V>()
4379 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
4380 Ok(cx.update_view(&view, update))
4381 })?
4382 }
4383
4384 /// Read the root view out of this window.
4385 ///
4386 /// This will fail if the window is closed or if the root view's type does not match `V`.
4387 pub fn read<'a>(&self, cx: &'a AppContext) -> Result<&'a V> {
4388 let x = cx
4389 .windows
4390 .get(self.id)
4391 .and_then(|window| {
4392 window
4393 .as_ref()
4394 .and_then(|window| window.root_view.clone())
4395 .map(|root_view| root_view.downcast::<V>())
4396 })
4397 .ok_or_else(|| anyhow!("window not found"))?
4398 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
4399
4400 Ok(x.read(cx))
4401 }
4402
4403 /// Read the root view out of this window, with a callback
4404 ///
4405 /// This will fail if the window is closed or if the root view's type does not match `V`.
4406 pub fn read_with<C, R>(&self, cx: &C, read_with: impl FnOnce(&V, &AppContext) -> R) -> Result<R>
4407 where
4408 C: Context,
4409 {
4410 cx.read_window(self, |root_view, cx| read_with(root_view.read(cx), cx))
4411 }
4412
4413 /// Read the root view pointer off of this window.
4414 ///
4415 /// This will fail if the window is closed or if the root view's type does not match `V`.
4416 pub fn root_view<C>(&self, cx: &C) -> Result<View<V>>
4417 where
4418 C: Context,
4419 {
4420 cx.read_window(self, |root_view, _cx| root_view.clone())
4421 }
4422
4423 /// Check if this window is 'active'.
4424 ///
4425 /// Will return `None` if the window is closed or currently
4426 /// borrowed.
4427 pub fn is_active(&self, cx: &mut AppContext) -> Option<bool> {
4428 cx.update_window(self.any_handle, |_, cx| cx.is_window_active())
4429 .ok()
4430 }
4431}
4432
4433impl<V> Copy for WindowHandle<V> {}
4434
4435impl<V> Clone for WindowHandle<V> {
4436 fn clone(&self) -> Self {
4437 *self
4438 }
4439}
4440
4441impl<V> PartialEq for WindowHandle<V> {
4442 fn eq(&self, other: &Self) -> bool {
4443 self.any_handle == other.any_handle
4444 }
4445}
4446
4447impl<V> Eq for WindowHandle<V> {}
4448
4449impl<V> Hash for WindowHandle<V> {
4450 fn hash<H: Hasher>(&self, state: &mut H) {
4451 self.any_handle.hash(state);
4452 }
4453}
4454
4455impl<V: 'static> From<WindowHandle<V>> for AnyWindowHandle {
4456 fn from(val: WindowHandle<V>) -> Self {
4457 val.any_handle
4458 }
4459}
4460
4461unsafe impl<V> Send for WindowHandle<V> {}
4462unsafe impl<V> Sync for WindowHandle<V> {}
4463
4464/// A handle to a window with any root view type, which can be downcast to a window with a specific root view type.
4465#[derive(Copy, Clone, PartialEq, Eq, Hash)]
4466pub struct AnyWindowHandle {
4467 pub(crate) id: WindowId,
4468 state_type: TypeId,
4469}
4470
4471impl AnyWindowHandle {
4472 /// Get the ID of this window.
4473 pub fn window_id(&self) -> WindowId {
4474 self.id
4475 }
4476
4477 /// Attempt to convert this handle to a window handle with a specific root view type.
4478 /// If the types do not match, this will return `None`.
4479 pub fn downcast<T: 'static>(&self) -> Option<WindowHandle<T>> {
4480 if TypeId::of::<T>() == self.state_type {
4481 Some(WindowHandle {
4482 any_handle: *self,
4483 state_type: PhantomData,
4484 })
4485 } else {
4486 None
4487 }
4488 }
4489
4490 /// Updates the state of the root view of this window.
4491 ///
4492 /// This will fail if the window has been closed.
4493 pub fn update<C, R>(
4494 self,
4495 cx: &mut C,
4496 update: impl FnOnce(AnyView, &mut WindowContext<'_>) -> R,
4497 ) -> Result<R>
4498 where
4499 C: Context,
4500 {
4501 cx.update_window(self, update)
4502 }
4503
4504 /// Read the state of the root view of this window.
4505 ///
4506 /// This will fail if the window has been closed.
4507 pub fn read<T, C, R>(self, cx: &C, read: impl FnOnce(View<T>, &AppContext) -> R) -> Result<R>
4508 where
4509 C: Context,
4510 T: 'static,
4511 {
4512 let view = self
4513 .downcast::<T>()
4514 .context("the type of the window's root view has changed")?;
4515
4516 cx.read_window(&view, read)
4517 }
4518}
4519
4520/// An identifier for an [`Element`](crate::Element).
4521///
4522/// Can be constructed with a string, a number, or both, as well
4523/// as other internal representations.
4524#[derive(Clone, Debug, Eq, PartialEq, Hash)]
4525pub enum ElementId {
4526 /// The ID of a View element
4527 View(EntityId),
4528 /// An integer ID.
4529 Integer(usize),
4530 /// A string based ID.
4531 Name(SharedString),
4532 /// A UUID.
4533 Uuid(Uuid),
4534 /// An ID that's equated with a focus handle.
4535 FocusHandle(FocusId),
4536 /// A combination of a name and an integer.
4537 NamedInteger(SharedString, usize),
4538}
4539
4540impl Display for ElementId {
4541 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
4542 match self {
4543 ElementId::View(entity_id) => write!(f, "view-{}", entity_id)?,
4544 ElementId::Integer(ix) => write!(f, "{}", ix)?,
4545 ElementId::Name(name) => write!(f, "{}", name)?,
4546 ElementId::FocusHandle(_) => write!(f, "FocusHandle")?,
4547 ElementId::NamedInteger(s, i) => write!(f, "{}-{}", s, i)?,
4548 ElementId::Uuid(uuid) => write!(f, "{}", uuid)?,
4549 }
4550
4551 Ok(())
4552 }
4553}
4554
4555impl TryInto<SharedString> for ElementId {
4556 type Error = anyhow::Error;
4557
4558 fn try_into(self) -> anyhow::Result<SharedString> {
4559 if let ElementId::Name(name) = self {
4560 Ok(name)
4561 } else {
4562 Err(anyhow!("element id is not string"))
4563 }
4564 }
4565}
4566
4567impl From<usize> for ElementId {
4568 fn from(id: usize) -> Self {
4569 ElementId::Integer(id)
4570 }
4571}
4572
4573impl From<i32> for ElementId {
4574 fn from(id: i32) -> Self {
4575 Self::Integer(id as usize)
4576 }
4577}
4578
4579impl From<SharedString> for ElementId {
4580 fn from(name: SharedString) -> Self {
4581 ElementId::Name(name)
4582 }
4583}
4584
4585impl From<&'static str> for ElementId {
4586 fn from(name: &'static str) -> Self {
4587 ElementId::Name(name.into())
4588 }
4589}
4590
4591impl<'a> From<&'a FocusHandle> for ElementId {
4592 fn from(handle: &'a FocusHandle) -> Self {
4593 ElementId::FocusHandle(handle.id)
4594 }
4595}
4596
4597impl From<(&'static str, EntityId)> for ElementId {
4598 fn from((name, id): (&'static str, EntityId)) -> Self {
4599 ElementId::NamedInteger(name.into(), id.as_u64() as usize)
4600 }
4601}
4602
4603impl From<(&'static str, usize)> for ElementId {
4604 fn from((name, id): (&'static str, usize)) -> Self {
4605 ElementId::NamedInteger(name.into(), id)
4606 }
4607}
4608
4609impl From<(&'static str, u64)> for ElementId {
4610 fn from((name, id): (&'static str, u64)) -> Self {
4611 ElementId::NamedInteger(name.into(), id as usize)
4612 }
4613}
4614
4615impl From<Uuid> for ElementId {
4616 fn from(value: Uuid) -> Self {
4617 Self::Uuid(value)
4618 }
4619}
4620
4621impl From<(&'static str, u32)> for ElementId {
4622 fn from((name, id): (&'static str, u32)) -> Self {
4623 ElementId::NamedInteger(name.into(), id as usize)
4624 }
4625}
4626
4627/// A rectangle to be rendered in the window at the given position and size.
4628/// Passed as an argument [`WindowContext::paint_quad`].
4629#[derive(Clone)]
4630pub struct PaintQuad {
4631 /// The bounds of the quad within the window.
4632 pub bounds: Bounds<Pixels>,
4633 /// The radii of the quad's corners.
4634 pub corner_radii: Corners<Pixels>,
4635 /// The background color of the quad.
4636 pub background: Hsla,
4637 /// The widths of the quad's borders.
4638 pub border_widths: Edges<Pixels>,
4639 /// The color of the quad's borders.
4640 pub border_color: Hsla,
4641}
4642
4643impl PaintQuad {
4644 /// Sets the corner radii of the quad.
4645 pub fn corner_radii(self, corner_radii: impl Into<Corners<Pixels>>) -> Self {
4646 PaintQuad {
4647 corner_radii: corner_radii.into(),
4648 ..self
4649 }
4650 }
4651
4652 /// Sets the border widths of the quad.
4653 pub fn border_widths(self, border_widths: impl Into<Edges<Pixels>>) -> Self {
4654 PaintQuad {
4655 border_widths: border_widths.into(),
4656 ..self
4657 }
4658 }
4659
4660 /// Sets the border color of the quad.
4661 pub fn border_color(self, border_color: impl Into<Hsla>) -> Self {
4662 PaintQuad {
4663 border_color: border_color.into(),
4664 ..self
4665 }
4666 }
4667
4668 /// Sets the background color of the quad.
4669 pub fn background(self, background: impl Into<Hsla>) -> Self {
4670 PaintQuad {
4671 background: background.into(),
4672 ..self
4673 }
4674 }
4675}
4676
4677/// Creates a quad with the given parameters.
4678pub fn quad(
4679 bounds: Bounds<Pixels>,
4680 corner_radii: impl Into<Corners<Pixels>>,
4681 background: impl Into<Hsla>,
4682 border_widths: impl Into<Edges<Pixels>>,
4683 border_color: impl Into<Hsla>,
4684) -> PaintQuad {
4685 PaintQuad {
4686 bounds,
4687 corner_radii: corner_radii.into(),
4688 background: background.into(),
4689 border_widths: border_widths.into(),
4690 border_color: border_color.into(),
4691 }
4692}
4693
4694/// Creates a filled quad with the given bounds and background color.
4695pub fn fill(bounds: impl Into<Bounds<Pixels>>, background: impl Into<Hsla>) -> PaintQuad {
4696 PaintQuad {
4697 bounds: bounds.into(),
4698 corner_radii: (0.).into(),
4699 background: background.into(),
4700 border_widths: (0.).into(),
4701 border_color: transparent_black(),
4702 }
4703}
4704
4705/// Creates a rectangle outline with the given bounds, border color, and a 1px border width
4706pub fn outline(bounds: impl Into<Bounds<Pixels>>, border_color: impl Into<Hsla>) -> PaintQuad {
4707 PaintQuad {
4708 bounds: bounds.into(),
4709 corner_radii: (0.).into(),
4710 background: transparent_black(),
4711 border_widths: (1.).into(),
4712 border_color: border_color.into(),
4713 }
4714}