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, Decorations, DevicePixels, DispatchActionListener,
5 DispatchNodeId, DispatchTree, DisplayId, Edges, Effect, Entity, EntityId, EventEmitter,
6 FileDropEvent, Flatten, FontId, Global, GlobalElementId, GlyphId, Hsla, ImageData,
7 InputHandler, IsZero, KeyBinding, KeyContext, KeyDownEvent, KeyEvent, KeyMatch, KeymatchResult,
8 Keystroke, KeystrokeEvent, LayoutId, LineLayoutIndex, Model, ModelContext, Modifiers,
9 ModifiersChangedEvent, MonochromeSprite, MouseButton, MouseEvent, MouseMoveEvent, MouseUpEvent,
10 Path, Pixels, PlatformAtlas, PlatformDisplay, PlatformInput, PlatformInputHandler,
11 PlatformWindow, Point, PolychromeSprite, PromptLevel, Quad, Render, RenderGlyphParams,
12 RenderImageParams, RenderSvgParams, ResizeEdge, ScaledPixels, Scene, Shadow, SharedString,
13 Size, StrikethroughStyle, Style, SubscriberSet, Subscription, TaffyLayoutEngine, Task,
14 TextStyle, TextStyleRefinement, TransformationMatrix, Underline, UnderlineStyle, View,
15 VisualContext, WeakView, WindowAppearance, WindowBackgroundAppearance, WindowBounds,
16 WindowControls, WindowDecorations, WindowOptions, WindowParams, WindowTextSystem,
17 SUBPIXEL_VARIANTS,
18};
19use anyhow::{anyhow, Context as _, Result};
20use collections::{FxHashMap, FxHashSet};
21use derive_more::{Deref, DerefMut};
22use futures::channel::oneshot;
23use futures::{future::Shared, FutureExt};
24#[cfg(target_os = "macos")]
25use media::core_video::CVImageBuffer;
26use parking_lot::RwLock;
27use refineable::Refineable;
28use slotmap::SlotMap;
29use smallvec::SmallVec;
30use std::{
31 any::{Any, TypeId},
32 borrow::{Borrow, BorrowMut, Cow},
33 cell::{Cell, RefCell},
34 cmp,
35 fmt::{Debug, Display},
36 future::Future,
37 hash::{Hash, Hasher},
38 marker::PhantomData,
39 mem,
40 ops::Range,
41 rc::Rc,
42 sync::{
43 atomic::{AtomicUsize, Ordering::SeqCst},
44 Arc, Weak,
45 },
46 time::{Duration, Instant},
47};
48use util::post_inc;
49use util::{measure, ResultExt};
50use uuid::Uuid;
51
52mod prompts;
53
54pub use prompts::*;
55
56pub(crate) const DEFAULT_WINDOW_SIZE: Size<Pixels> = size(px(1024.), px(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 =
90 Box<dyn FnMut(&WindowFocusEvent, &mut WindowContext) -> bool + 'static>;
91
92struct WindowFocusEvent {
93 previous_focus_path: SmallVec<[FocusId; 8]>,
94 current_focus_path: SmallVec<[FocusId; 8]>,
95}
96
97impl WindowFocusEvent {
98 pub fn is_focus_in(&self, focus_id: FocusId) -> bool {
99 !self.previous_focus_path.contains(&focus_id) && self.current_focus_path.contains(&focus_id)
100 }
101
102 pub fn is_focus_out(&self, focus_id: FocusId) -> bool {
103 self.previous_focus_path.contains(&focus_id) && !self.current_focus_path.contains(&focus_id)
104 }
105}
106
107/// This is provided when subscribing for `ViewContext::on_focus_out` events.
108pub struct FocusOutEvent {
109 /// A weak focus handle representing what was blurred.
110 pub blurred: WeakFocusHandle,
111}
112
113slotmap::new_key_type! {
114 /// A globally unique identifier for a focusable element.
115 pub struct FocusId;
116}
117
118thread_local! {
119 /// 8MB wasn't quite enough...
120 pub(crate) static ELEMENT_ARENA: RefCell<Arena> = RefCell::new(Arena::new(32 * 1024 * 1024));
121}
122
123impl FocusId {
124 /// Obtains whether the element associated with this handle is currently focused.
125 pub fn is_focused(&self, cx: &WindowContext) -> bool {
126 cx.window.focus == Some(*self)
127 }
128
129 /// Obtains whether the element associated with this handle contains the focused
130 /// element or is itself focused.
131 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
132 cx.focused()
133 .map_or(false, |focused| self.contains(focused.id, cx))
134 }
135
136 /// Obtains whether the element associated with this handle is contained within the
137 /// focused element or is itself focused.
138 pub fn within_focused(&self, cx: &WindowContext) -> bool {
139 let focused = cx.focused();
140 focused.map_or(false, |focused| focused.id.contains(*self, cx))
141 }
142
143 /// Obtains whether this handle contains the given handle in the most recently rendered frame.
144 pub(crate) fn contains(&self, other: Self, cx: &WindowContext) -> bool {
145 cx.window
146 .rendered_frame
147 .dispatch_tree
148 .focus_contains(*self, other)
149 }
150}
151
152/// A handle which can be used to track and manipulate the focused element in a window.
153pub struct FocusHandle {
154 pub(crate) id: FocusId,
155 handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
156}
157
158impl std::fmt::Debug for FocusHandle {
159 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
160 f.write_fmt(format_args!("FocusHandle({:?})", self.id))
161 }
162}
163
164impl FocusHandle {
165 pub(crate) fn new(handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>) -> Self {
166 let id = handles.write().insert(AtomicUsize::new(1));
167 Self {
168 id,
169 handles: handles.clone(),
170 }
171 }
172
173 pub(crate) fn for_id(
174 id: FocusId,
175 handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
176 ) -> Option<Self> {
177 let lock = handles.read();
178 let ref_count = lock.get(id)?;
179 if ref_count.load(SeqCst) == 0 {
180 None
181 } else {
182 ref_count.fetch_add(1, SeqCst);
183 Some(Self {
184 id,
185 handles: handles.clone(),
186 })
187 }
188 }
189
190 /// Converts this focus handle into a weak variant, which does not prevent it from being released.
191 pub fn downgrade(&self) -> WeakFocusHandle {
192 WeakFocusHandle {
193 id: self.id,
194 handles: Arc::downgrade(&self.handles),
195 }
196 }
197
198 /// Moves the focus to the element associated with this handle.
199 pub fn focus(&self, cx: &mut WindowContext) {
200 cx.focus(self)
201 }
202
203 /// Obtains whether the element associated with this handle is currently focused.
204 pub fn is_focused(&self, cx: &WindowContext) -> bool {
205 self.id.is_focused(cx)
206 }
207
208 /// Obtains whether the element associated with this handle contains the focused
209 /// element or is itself focused.
210 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
211 self.id.contains_focused(cx)
212 }
213
214 /// Obtains whether the element associated with this handle is contained within the
215 /// focused element or is itself focused.
216 pub fn within_focused(&self, cx: &WindowContext) -> bool {
217 self.id.within_focused(cx)
218 }
219
220 /// Obtains whether this handle contains the given handle in the most recently rendered frame.
221 pub fn contains(&self, other: &Self, cx: &WindowContext) -> bool {
222 self.id.contains(other.id, cx)
223 }
224
225 /// Dispatch an action on the element that rendered this focus handle
226 pub fn dispatch_action(&self, action: &dyn Action, cx: &mut WindowContext) {
227 if let Some(node_id) = cx
228 .window
229 .rendered_frame
230 .dispatch_tree
231 .focusable_node_id(self.id)
232 {
233 cx.dispatch_action_on_node(node_id, action)
234 }
235 }
236}
237
238impl Clone for FocusHandle {
239 fn clone(&self) -> Self {
240 Self::for_id(self.id, &self.handles).unwrap()
241 }
242}
243
244impl PartialEq for FocusHandle {
245 fn eq(&self, other: &Self) -> bool {
246 self.id == other.id
247 }
248}
249
250impl Eq for FocusHandle {}
251
252impl Drop for FocusHandle {
253 fn drop(&mut self) {
254 self.handles
255 .read()
256 .get(self.id)
257 .unwrap()
258 .fetch_sub(1, SeqCst);
259 }
260}
261
262/// A weak reference to a focus handle.
263#[derive(Clone, Debug)]
264pub struct WeakFocusHandle {
265 pub(crate) id: FocusId,
266 handles: Weak<RwLock<SlotMap<FocusId, AtomicUsize>>>,
267}
268
269impl WeakFocusHandle {
270 /// Attempts to upgrade the [WeakFocusHandle] to a [FocusHandle].
271 pub fn upgrade(&self) -> Option<FocusHandle> {
272 let handles = self.handles.upgrade()?;
273 FocusHandle::for_id(self.id, &handles)
274 }
275}
276
277impl PartialEq for WeakFocusHandle {
278 fn eq(&self, other: &WeakFocusHandle) -> bool {
279 self.id == other.id
280 }
281}
282
283impl Eq for WeakFocusHandle {}
284
285impl PartialEq<FocusHandle> for WeakFocusHandle {
286 fn eq(&self, other: &FocusHandle) -> bool {
287 self.id == other.id
288 }
289}
290
291impl PartialEq<WeakFocusHandle> for FocusHandle {
292 fn eq(&self, other: &WeakFocusHandle) -> bool {
293 self.id == other.id
294 }
295}
296
297/// FocusableView allows users of your view to easily
298/// focus it (using cx.focus_view(view))
299pub trait FocusableView: 'static + Render {
300 /// Returns the focus handle associated with this view.
301 fn focus_handle(&self, cx: &AppContext) -> FocusHandle;
302}
303
304/// ManagedView is a view (like a Modal, Popover, Menu, etc.)
305/// where the lifecycle of the view is handled by another view.
306pub trait ManagedView: FocusableView + EventEmitter<DismissEvent> {}
307
308impl<M: FocusableView + EventEmitter<DismissEvent>> ManagedView for M {}
309
310/// Emitted by implementers of [`ManagedView`] to indicate the view should be dismissed, such as when a view is presented as a modal.
311pub struct DismissEvent;
312
313type FrameCallback = Box<dyn FnOnce(&mut WindowContext)>;
314
315pub(crate) type AnyMouseListener =
316 Box<dyn FnMut(&dyn Any, DispatchPhase, &mut WindowContext) + 'static>;
317
318#[derive(Clone)]
319pub(crate) struct CursorStyleRequest {
320 pub(crate) hitbox_id: HitboxId,
321 pub(crate) style: CursorStyle,
322}
323
324/// An identifier for a [Hitbox].
325#[derive(Copy, Clone, Debug, Default, Eq, PartialEq)]
326pub struct HitboxId(usize);
327
328impl HitboxId {
329 /// Checks if the hitbox with this id is currently hovered.
330 pub fn is_hovered(&self, cx: &WindowContext) -> bool {
331 cx.window.mouse_hit_test.0.contains(self)
332 }
333}
334
335/// A rectangular region that potentially blocks hitboxes inserted prior.
336/// See [WindowContext::insert_hitbox] for more details.
337#[derive(Clone, Debug, Deref)]
338pub struct Hitbox {
339 /// A unique identifier for the hitbox.
340 pub id: HitboxId,
341 /// The bounds of the hitbox.
342 #[deref]
343 pub bounds: Bounds<Pixels>,
344 /// The content mask when the hitbox was inserted.
345 pub content_mask: ContentMask<Pixels>,
346 /// Whether the hitbox occludes other hitboxes inserted prior.
347 pub opaque: bool,
348}
349
350impl Hitbox {
351 /// Checks if the hitbox is currently hovered.
352 pub fn is_hovered(&self, cx: &WindowContext) -> bool {
353 self.id.is_hovered(cx)
354 }
355}
356
357#[derive(Default, Eq, PartialEq)]
358pub(crate) struct HitTest(SmallVec<[HitboxId; 8]>);
359
360/// An identifier for a tooltip.
361#[derive(Copy, Clone, Debug, Default, Eq, PartialEq)]
362pub struct TooltipId(usize);
363
364impl TooltipId {
365 /// Checks if the tooltip is currently hovered.
366 pub fn is_hovered(&self, cx: &WindowContext) -> bool {
367 cx.window
368 .tooltip_bounds
369 .as_ref()
370 .map_or(false, |tooltip_bounds| {
371 tooltip_bounds.id == *self && tooltip_bounds.bounds.contains(&cx.mouse_position())
372 })
373 }
374}
375
376pub(crate) struct TooltipBounds {
377 id: TooltipId,
378 bounds: Bounds<Pixels>,
379}
380
381#[derive(Clone)]
382pub(crate) struct TooltipRequest {
383 id: TooltipId,
384 tooltip: AnyTooltip,
385}
386
387pub(crate) struct DeferredDraw {
388 priority: usize,
389 parent_node: DispatchNodeId,
390 element_id_stack: SmallVec<[ElementId; 32]>,
391 text_style_stack: Vec<TextStyleRefinement>,
392 element: Option<AnyElement>,
393 absolute_offset: Point<Pixels>,
394 prepaint_range: Range<PrepaintStateIndex>,
395 paint_range: Range<PaintIndex>,
396}
397
398pub(crate) struct Frame {
399 pub(crate) focus: Option<FocusId>,
400 pub(crate) window_active: bool,
401 pub(crate) element_states: FxHashMap<(GlobalElementId, TypeId), ElementStateBox>,
402 accessed_element_states: Vec<(GlobalElementId, TypeId)>,
403 pub(crate) mouse_listeners: Vec<Option<AnyMouseListener>>,
404 pub(crate) dispatch_tree: DispatchTree,
405 pub(crate) scene: Scene,
406 pub(crate) hitboxes: Vec<Hitbox>,
407 pub(crate) deferred_draws: Vec<DeferredDraw>,
408 pub(crate) input_handlers: Vec<Option<PlatformInputHandler>>,
409 pub(crate) tooltip_requests: Vec<Option<TooltipRequest>>,
410 pub(crate) cursor_styles: Vec<CursorStyleRequest>,
411 #[cfg(any(test, feature = "test-support"))]
412 pub(crate) debug_bounds: FxHashMap<String, Bounds<Pixels>>,
413}
414
415#[derive(Clone, Default)]
416pub(crate) struct PrepaintStateIndex {
417 hitboxes_index: usize,
418 tooltips_index: usize,
419 deferred_draws_index: usize,
420 dispatch_tree_index: usize,
421 accessed_element_states_index: usize,
422 line_layout_index: LineLayoutIndex,
423}
424
425#[derive(Clone, Default)]
426pub(crate) struct PaintIndex {
427 scene_index: usize,
428 mouse_listeners_index: usize,
429 input_handlers_index: usize,
430 cursor_styles_index: usize,
431 accessed_element_states_index: usize,
432 line_layout_index: LineLayoutIndex,
433}
434
435impl Frame {
436 pub(crate) fn new(dispatch_tree: DispatchTree) -> Self {
437 Frame {
438 focus: None,
439 window_active: false,
440 element_states: FxHashMap::default(),
441 accessed_element_states: Vec::new(),
442 mouse_listeners: Vec::new(),
443 dispatch_tree,
444 scene: Scene::default(),
445 hitboxes: Vec::new(),
446 deferred_draws: Vec::new(),
447 input_handlers: Vec::new(),
448 tooltip_requests: Vec::new(),
449 cursor_styles: Vec::new(),
450
451 #[cfg(any(test, feature = "test-support"))]
452 debug_bounds: FxHashMap::default(),
453 }
454 }
455
456 pub(crate) fn clear(&mut self) {
457 self.element_states.clear();
458 self.accessed_element_states.clear();
459 self.mouse_listeners.clear();
460 self.dispatch_tree.clear();
461 self.scene.clear();
462 self.input_handlers.clear();
463 self.tooltip_requests.clear();
464 self.cursor_styles.clear();
465 self.hitboxes.clear();
466 self.deferred_draws.clear();
467 }
468
469 pub(crate) fn hit_test(&self, position: Point<Pixels>) -> HitTest {
470 let mut hit_test = HitTest::default();
471 for hitbox in self.hitboxes.iter().rev() {
472 let bounds = hitbox.bounds.intersect(&hitbox.content_mask.bounds);
473 if bounds.contains(&position) {
474 hit_test.0.push(hitbox.id);
475 if hitbox.opaque {
476 break;
477 }
478 }
479 }
480 hit_test
481 }
482
483 pub(crate) fn focus_path(&self) -> SmallVec<[FocusId; 8]> {
484 self.focus
485 .map(|focus_id| self.dispatch_tree.focus_path(focus_id))
486 .unwrap_or_default()
487 }
488
489 pub(crate) fn finish(&mut self, prev_frame: &mut Self) {
490 for element_state_key in &self.accessed_element_states {
491 if let Some((element_state_key, element_state)) =
492 prev_frame.element_states.remove_entry(element_state_key)
493 {
494 self.element_states.insert(element_state_key, element_state);
495 }
496 }
497
498 self.scene.finish();
499 }
500}
501
502// Holds the state for a specific window.
503#[doc(hidden)]
504pub struct Window {
505 pub(crate) handle: AnyWindowHandle,
506 pub(crate) removed: bool,
507 pub(crate) platform_window: Box<dyn PlatformWindow>,
508 display_id: Option<DisplayId>,
509 sprite_atlas: Arc<dyn PlatformAtlas>,
510 text_system: Arc<WindowTextSystem>,
511 rem_size: Pixels,
512 /// The stack of override values for the window's rem size.
513 ///
514 /// This is used by `with_rem_size` to allow rendering an element tree with
515 /// a given rem size.
516 rem_size_override_stack: SmallVec<[Pixels; 8]>,
517 pub(crate) viewport_size: Size<Pixels>,
518 layout_engine: Option<TaffyLayoutEngine>,
519 pub(crate) root_view: Option<AnyView>,
520 pub(crate) element_id_stack: SmallVec<[ElementId; 32]>,
521 pub(crate) text_style_stack: Vec<TextStyleRefinement>,
522 pub(crate) element_offset_stack: Vec<Point<Pixels>>,
523 pub(crate) content_mask_stack: Vec<ContentMask<Pixels>>,
524 pub(crate) requested_autoscroll: Option<Bounds<Pixels>>,
525 pub(crate) rendered_frame: Frame,
526 pub(crate) next_frame: Frame,
527 pub(crate) next_hitbox_id: HitboxId,
528 pub(crate) next_tooltip_id: TooltipId,
529 pub(crate) tooltip_bounds: Option<TooltipBounds>,
530 next_frame_callbacks: Rc<RefCell<Vec<FrameCallback>>>,
531 pub(crate) dirty_views: FxHashSet<EntityId>,
532 pub(crate) focus_handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
533 focus_listeners: SubscriberSet<(), AnyWindowFocusListener>,
534 focus_lost_listeners: SubscriberSet<(), AnyObserver>,
535 default_prevented: bool,
536 mouse_position: Point<Pixels>,
537 mouse_hit_test: HitTest,
538 modifiers: Modifiers,
539 scale_factor: f32,
540 bounds_observers: SubscriberSet<(), AnyObserver>,
541 appearance: WindowAppearance,
542 appearance_observers: SubscriberSet<(), AnyObserver>,
543 active: Rc<Cell<bool>>,
544 hovered: Rc<Cell<bool>>,
545 pub(crate) dirty: Rc<Cell<bool>>,
546 pub(crate) needs_present: Rc<Cell<bool>>,
547 pub(crate) last_input_timestamp: Rc<Cell<Instant>>,
548 pub(crate) refreshing: bool,
549 pub(crate) draw_phase: DrawPhase,
550 activation_observers: SubscriberSet<(), AnyObserver>,
551 pub(crate) focus: Option<FocusId>,
552 focus_enabled: bool,
553 pending_input: Option<PendingInput>,
554 pending_modifier: ModifierState,
555 pending_input_observers: SubscriberSet<(), AnyObserver>,
556 prompt: Option<RenderablePromptHandle>,
557}
558
559#[derive(Clone, Debug, Default)]
560struct ModifierState {
561 modifiers: Modifiers,
562 saw_keystroke: bool,
563}
564
565#[derive(Clone, Copy, Debug, Eq, PartialEq)]
566pub(crate) enum DrawPhase {
567 None,
568 Prepaint,
569 Paint,
570 Focus,
571}
572
573#[derive(Default, Debug)]
574struct PendingInput {
575 keystrokes: SmallVec<[Keystroke; 1]>,
576 bindings: SmallVec<[KeyBinding; 1]>,
577 focus: Option<FocusId>,
578 timer: Option<Task<()>>,
579}
580
581impl PendingInput {
582 fn input(&self) -> String {
583 self.keystrokes
584 .iter()
585 .flat_map(|k| k.ime_key.clone())
586 .collect::<Vec<String>>()
587 .join("")
588 }
589
590 fn used_by_binding(&self, binding: &KeyBinding) -> bool {
591 if self.keystrokes.is_empty() {
592 return true;
593 }
594 let keystroke = &self.keystrokes[0];
595 for candidate in keystroke.match_candidates() {
596 if binding.match_keystrokes(&[candidate]) == KeyMatch::Pending {
597 return true;
598 }
599 }
600 false
601 }
602}
603
604pub(crate) struct ElementStateBox {
605 pub(crate) inner: Box<dyn Any>,
606 #[cfg(debug_assertions)]
607 pub(crate) type_name: &'static str,
608}
609
610fn default_bounds(display_id: Option<DisplayId>, cx: &mut AppContext) -> Bounds<Pixels> {
611 const DEFAULT_WINDOW_OFFSET: Point<Pixels> = point(px(0.), px(35.));
612
613 cx.active_window()
614 .and_then(|w| w.update(cx, |_, cx| cx.bounds()).ok())
615 .map(|mut bounds| {
616 bounds.origin += DEFAULT_WINDOW_OFFSET;
617 bounds
618 })
619 .unwrap_or_else(|| {
620 let display = display_id
621 .map(|id| cx.find_display(id))
622 .unwrap_or_else(|| cx.primary_display());
623
624 display
625 .map(|display| display.default_bounds())
626 .unwrap_or_else(|| Bounds::new(point(px(0.), px(0.)), DEFAULT_WINDOW_SIZE))
627 })
628}
629
630impl Window {
631 pub(crate) fn new(
632 handle: AnyWindowHandle,
633 options: WindowOptions,
634 cx: &mut AppContext,
635 ) -> Result<Self> {
636 let WindowOptions {
637 window_bounds,
638 titlebar,
639 focus,
640 show,
641 kind,
642 is_movable,
643 display_id,
644 window_background,
645 app_id,
646 window_min_size,
647 window_decorations,
648 } = options;
649
650 let bounds = window_bounds
651 .map(|bounds| bounds.get_bounds())
652 .unwrap_or_else(|| default_bounds(display_id, cx));
653 let mut platform_window = cx.platform.open_window(
654 handle,
655 WindowParams {
656 bounds,
657 titlebar,
658 kind,
659 is_movable,
660 focus,
661 show,
662 display_id,
663 window_min_size,
664 },
665 )?;
666 let display_id = platform_window.display().map(|display| display.id());
667 let sprite_atlas = platform_window.sprite_atlas();
668 let mouse_position = platform_window.mouse_position();
669 let modifiers = platform_window.modifiers();
670 let content_size = platform_window.content_size();
671 let scale_factor = platform_window.scale_factor();
672 let appearance = platform_window.appearance();
673 let text_system = Arc::new(WindowTextSystem::new(cx.text_system().clone()));
674 let dirty = Rc::new(Cell::new(true));
675 let active = Rc::new(Cell::new(platform_window.is_active()));
676 let hovered = Rc::new(Cell::new(platform_window.is_hovered()));
677 let needs_present = Rc::new(Cell::new(false));
678 let next_frame_callbacks: Rc<RefCell<Vec<FrameCallback>>> = Default::default();
679 let last_input_timestamp = Rc::new(Cell::new(Instant::now()));
680
681 platform_window
682 .request_decorations(window_decorations.unwrap_or(WindowDecorations::Server));
683 platform_window.set_background_appearance(window_background);
684
685 if let Some(ref window_open_state) = window_bounds {
686 match window_open_state {
687 WindowBounds::Fullscreen(_) => platform_window.toggle_fullscreen(),
688 WindowBounds::Maximized(_) => platform_window.zoom(),
689 WindowBounds::Windowed(_) => {}
690 }
691 }
692
693 platform_window.on_close(Box::new({
694 let mut cx = cx.to_async();
695 move || {
696 let _ = handle.update(&mut cx, |_, cx| cx.remove_window());
697 }
698 }));
699 platform_window.on_request_frame(Box::new({
700 let mut cx = cx.to_async();
701 let dirty = dirty.clone();
702 let active = active.clone();
703 let needs_present = needs_present.clone();
704 let next_frame_callbacks = next_frame_callbacks.clone();
705 let last_input_timestamp = last_input_timestamp.clone();
706 move || {
707 let next_frame_callbacks = next_frame_callbacks.take();
708 if !next_frame_callbacks.is_empty() {
709 handle
710 .update(&mut cx, |_, cx| {
711 for callback in next_frame_callbacks {
712 callback(cx);
713 }
714 })
715 .log_err();
716 }
717
718 // Keep presenting the current scene for 1 extra second since the
719 // last input to prevent the display from underclocking the refresh rate.
720 let needs_present = needs_present.get()
721 || (active.get()
722 && last_input_timestamp.get().elapsed() < Duration::from_secs(1));
723
724 if dirty.get() {
725 measure("frame duration", || {
726 handle
727 .update(&mut cx, |_, cx| {
728 cx.draw();
729 cx.present();
730 })
731 .log_err();
732 })
733 } else if needs_present {
734 handle.update(&mut cx, |_, cx| cx.present()).log_err();
735 }
736
737 handle
738 .update(&mut cx, |_, cx| {
739 cx.complete_frame();
740 })
741 .log_err();
742 }
743 }));
744 platform_window.on_resize(Box::new({
745 let mut cx = cx.to_async();
746 move |_, _| {
747 handle
748 .update(&mut cx, |_, cx| cx.bounds_changed())
749 .log_err();
750 }
751 }));
752 platform_window.on_moved(Box::new({
753 let mut cx = cx.to_async();
754 move || {
755 handle
756 .update(&mut cx, |_, cx| cx.bounds_changed())
757 .log_err();
758 }
759 }));
760 platform_window.on_appearance_changed(Box::new({
761 let mut cx = cx.to_async();
762 move || {
763 handle
764 .update(&mut cx, |_, cx| cx.appearance_changed())
765 .log_err();
766 }
767 }));
768 platform_window.on_active_status_change(Box::new({
769 let mut cx = cx.to_async();
770 move |active| {
771 handle
772 .update(&mut cx, |_, cx| {
773 cx.window.active.set(active);
774 cx.window
775 .activation_observers
776 .clone()
777 .retain(&(), |callback| callback(cx));
778 cx.refresh();
779 })
780 .log_err();
781 }
782 }));
783 platform_window.on_hover_status_change(Box::new({
784 let mut cx = cx.to_async();
785 move |active| {
786 handle
787 .update(&mut cx, |_, cx| {
788 cx.window.hovered.set(active);
789 cx.refresh();
790 })
791 .log_err();
792 }
793 }));
794 platform_window.on_input({
795 let mut cx = cx.to_async();
796 Box::new(move |event| {
797 handle
798 .update(&mut cx, |_, cx| cx.dispatch_event(event))
799 .log_err()
800 .unwrap_or(DispatchEventResult::default())
801 })
802 });
803
804 if let Some(app_id) = app_id {
805 platform_window.set_app_id(&app_id);
806 }
807
808 Ok(Window {
809 handle,
810 removed: false,
811 platform_window,
812 display_id,
813 sprite_atlas,
814 text_system,
815 rem_size: px(16.),
816 rem_size_override_stack: SmallVec::new(),
817 viewport_size: content_size,
818 layout_engine: Some(TaffyLayoutEngine::new()),
819 root_view: None,
820 element_id_stack: SmallVec::default(),
821 text_style_stack: Vec::new(),
822 element_offset_stack: Vec::new(),
823 content_mask_stack: Vec::new(),
824 requested_autoscroll: None,
825 rendered_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
826 next_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
827 next_frame_callbacks,
828 next_hitbox_id: HitboxId::default(),
829 next_tooltip_id: TooltipId::default(),
830 tooltip_bounds: None,
831 dirty_views: FxHashSet::default(),
832 focus_handles: Arc::new(RwLock::new(SlotMap::with_key())),
833 focus_listeners: SubscriberSet::new(),
834 focus_lost_listeners: SubscriberSet::new(),
835 default_prevented: true,
836 mouse_position,
837 mouse_hit_test: HitTest::default(),
838 modifiers,
839 scale_factor,
840 bounds_observers: SubscriberSet::new(),
841 appearance,
842 appearance_observers: SubscriberSet::new(),
843 active,
844 hovered,
845 dirty,
846 needs_present,
847 last_input_timestamp,
848 refreshing: false,
849 draw_phase: DrawPhase::None,
850 activation_observers: SubscriberSet::new(),
851 focus: None,
852 focus_enabled: true,
853 pending_input: None,
854 pending_modifier: ModifierState::default(),
855 pending_input_observers: SubscriberSet::new(),
856 prompt: None,
857 })
858 }
859 fn new_focus_listener(
860 &mut self,
861 value: AnyWindowFocusListener,
862 ) -> (Subscription, impl FnOnce()) {
863 self.focus_listeners.insert((), value)
864 }
865}
866
867#[derive(Clone, Debug, Default, PartialEq, Eq)]
868pub(crate) struct DispatchEventResult {
869 pub propagate: bool,
870 pub default_prevented: bool,
871}
872
873/// Indicates which region of the window is visible. Content falling outside of this mask will not be
874/// rendered. Currently, only rectangular content masks are supported, but we give the mask its own type
875/// to leave room to support more complex shapes in the future.
876#[derive(Clone, Debug, Default, PartialEq, Eq)]
877#[repr(C)]
878pub struct ContentMask<P: Clone + Default + Debug> {
879 /// The bounds
880 pub bounds: Bounds<P>,
881}
882
883impl ContentMask<Pixels> {
884 /// Scale the content mask's pixel units by the given scaling factor.
885 pub fn scale(&self, factor: f32) -> ContentMask<ScaledPixels> {
886 ContentMask {
887 bounds: self.bounds.scale(factor),
888 }
889 }
890
891 /// Intersect the content mask with the given content mask.
892 pub fn intersect(&self, other: &Self) -> Self {
893 let bounds = self.bounds.intersect(&other.bounds);
894 ContentMask { bounds }
895 }
896}
897
898/// Provides access to application state in the context of a single window. Derefs
899/// to an [`AppContext`], so you can also pass a [`WindowContext`] to any method that takes
900/// an [`AppContext`] and call any [`AppContext`] methods.
901pub struct WindowContext<'a> {
902 pub(crate) app: &'a mut AppContext,
903 pub(crate) window: &'a mut Window,
904}
905
906impl<'a> WindowContext<'a> {
907 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window) -> Self {
908 Self { app, window }
909 }
910
911 /// Obtain a handle to the window that belongs to this context.
912 pub fn window_handle(&self) -> AnyWindowHandle {
913 self.window.handle
914 }
915
916 /// Mark the window as dirty, scheduling it to be redrawn on the next frame.
917 pub fn refresh(&mut self) {
918 if self.window.draw_phase == DrawPhase::None {
919 self.window.refreshing = true;
920 self.window.dirty.set(true);
921 }
922 }
923
924 /// Indicate that this view has changed, which will invoke any observers and also mark the window as dirty.
925 /// If this view or any of its ancestors are *cached*, notifying it will cause it or its ancestors to be redrawn.
926 pub fn notify(&mut self, view_id: EntityId) {
927 for view_id in self
928 .window
929 .rendered_frame
930 .dispatch_tree
931 .view_path(view_id)
932 .into_iter()
933 .rev()
934 {
935 if !self.window.dirty_views.insert(view_id) {
936 break;
937 }
938 }
939
940 if self.window.draw_phase == DrawPhase::None {
941 self.window.dirty.set(true);
942 self.app.push_effect(Effect::Notify { emitter: view_id });
943 }
944 }
945
946 /// Close this window.
947 pub fn remove_window(&mut self) {
948 self.window.removed = true;
949 }
950
951 /// Obtain a new [`FocusHandle`], which allows you to track and manipulate the keyboard focus
952 /// for elements rendered within this window.
953 pub fn focus_handle(&mut self) -> FocusHandle {
954 FocusHandle::new(&self.window.focus_handles)
955 }
956
957 /// Obtain the currently focused [`FocusHandle`]. If no elements are focused, returns `None`.
958 pub fn focused(&self) -> Option<FocusHandle> {
959 self.window
960 .focus
961 .and_then(|id| FocusHandle::for_id(id, &self.window.focus_handles))
962 }
963
964 /// Move focus to the element associated with the given [`FocusHandle`].
965 pub fn focus(&mut self, handle: &FocusHandle) {
966 if !self.window.focus_enabled || self.window.focus == Some(handle.id) {
967 return;
968 }
969
970 self.window.focus = Some(handle.id);
971 self.window
972 .rendered_frame
973 .dispatch_tree
974 .clear_pending_keystrokes();
975 self.refresh();
976 }
977
978 /// Remove focus from all elements within this context's window.
979 pub fn blur(&mut self) {
980 if !self.window.focus_enabled {
981 return;
982 }
983
984 self.window.focus = None;
985 self.refresh();
986 }
987
988 /// Blur the window and don't allow anything in it to be focused again.
989 pub fn disable_focus(&mut self) {
990 self.blur();
991 self.window.focus_enabled = false;
992 }
993
994 /// Accessor for the text system.
995 pub fn text_system(&self) -> &Arc<WindowTextSystem> {
996 &self.window.text_system
997 }
998
999 /// The current text style. Which is composed of all the style refinements provided to `with_text_style`.
1000 pub fn text_style(&self) -> TextStyle {
1001 let mut style = TextStyle::default();
1002 for refinement in &self.window.text_style_stack {
1003 style.refine(refinement);
1004 }
1005 style
1006 }
1007
1008 /// Check if the platform window is maximized
1009 /// On some platforms (namely Windows) this is different than the bounds being the size of the display
1010 pub fn is_maximized(&self) -> bool {
1011 self.window.platform_window.is_maximized()
1012 }
1013
1014 /// request a certain window decoration (Wayland)
1015 pub fn request_decorations(&self, decorations: WindowDecorations) {
1016 self.window.platform_window.request_decorations(decorations);
1017 }
1018
1019 /// Start a window resize operation (Wayland)
1020 pub fn start_window_resize(&self, edge: ResizeEdge) {
1021 self.window.platform_window.start_window_resize(edge);
1022 }
1023
1024 /// Return the `WindowBounds` to indicate that how a window should be opened
1025 /// after it has been closed
1026 pub fn window_bounds(&self) -> WindowBounds {
1027 self.window.platform_window.window_bounds()
1028 }
1029
1030 /// Dispatch the given action on the currently focused element.
1031 pub fn dispatch_action(&mut self, action: Box<dyn Action>) {
1032 let focus_handle = self.focused();
1033
1034 let window = self.window.handle;
1035 self.app.defer(move |cx| {
1036 window
1037 .update(cx, |_, cx| {
1038 let node_id = focus_handle
1039 .and_then(|handle| {
1040 cx.window
1041 .rendered_frame
1042 .dispatch_tree
1043 .focusable_node_id(handle.id)
1044 })
1045 .unwrap_or_else(|| cx.window.rendered_frame.dispatch_tree.root_node_id());
1046
1047 cx.dispatch_action_on_node(node_id, action.as_ref());
1048 })
1049 .log_err();
1050 })
1051 }
1052
1053 pub(crate) fn dispatch_keystroke_observers(
1054 &mut self,
1055 event: &dyn Any,
1056 action: Option<Box<dyn Action>>,
1057 ) {
1058 let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() else {
1059 return;
1060 };
1061
1062 self.keystroke_observers
1063 .clone()
1064 .retain(&(), move |callback| {
1065 (callback)(
1066 &KeystrokeEvent {
1067 keystroke: key_down_event.keystroke.clone(),
1068 action: action.as_ref().map(|action| action.boxed_clone()),
1069 },
1070 self,
1071 );
1072 true
1073 });
1074 }
1075
1076 pub(crate) fn clear_pending_keystrokes(&mut self) {
1077 self.window
1078 .rendered_frame
1079 .dispatch_tree
1080 .clear_pending_keystrokes();
1081 self.window
1082 .next_frame
1083 .dispatch_tree
1084 .clear_pending_keystrokes();
1085 }
1086
1087 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
1088 /// that are currently on the stack to be returned to the app.
1089 pub fn defer(&mut self, f: impl FnOnce(&mut WindowContext) + 'static) {
1090 let handle = self.window.handle;
1091 self.app.defer(move |cx| {
1092 handle.update(cx, |_, cx| f(cx)).ok();
1093 });
1094 }
1095
1096 /// Subscribe to events emitted by a model or view.
1097 /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
1098 /// 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.
1099 pub fn observe<E, T>(
1100 &mut self,
1101 entity: &E,
1102 mut on_notify: impl FnMut(E, &mut WindowContext<'_>) + 'static,
1103 ) -> Subscription
1104 where
1105 E: Entity<T>,
1106 {
1107 let entity_id = entity.entity_id();
1108 let entity = entity.downgrade();
1109 let window_handle = self.window.handle;
1110 self.app.new_observer(
1111 entity_id,
1112 Box::new(move |cx| {
1113 window_handle
1114 .update(cx, |_, cx| {
1115 if let Some(handle) = E::upgrade_from(&entity) {
1116 on_notify(handle, cx);
1117 true
1118 } else {
1119 false
1120 }
1121 })
1122 .unwrap_or(false)
1123 }),
1124 )
1125 }
1126
1127 /// Subscribe to events emitted by a model or view.
1128 /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
1129 /// 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.
1130 pub fn subscribe<Emitter, E, Evt>(
1131 &mut self,
1132 entity: &E,
1133 mut on_event: impl FnMut(E, &Evt, &mut WindowContext<'_>) + 'static,
1134 ) -> Subscription
1135 where
1136 Emitter: EventEmitter<Evt>,
1137 E: Entity<Emitter>,
1138 Evt: 'static,
1139 {
1140 let entity_id = entity.entity_id();
1141 let entity = entity.downgrade();
1142 let window_handle = self.window.handle;
1143 self.app.new_subscription(
1144 entity_id,
1145 (
1146 TypeId::of::<Evt>(),
1147 Box::new(move |event, cx| {
1148 window_handle
1149 .update(cx, |_, cx| {
1150 if let Some(handle) = E::upgrade_from(&entity) {
1151 let event = event.downcast_ref().expect("invalid event type");
1152 on_event(handle, event, cx);
1153 true
1154 } else {
1155 false
1156 }
1157 })
1158 .unwrap_or(false)
1159 }),
1160 ),
1161 )
1162 }
1163
1164 /// Creates an [`AsyncWindowContext`], which has a static lifetime and can be held across
1165 /// await points in async code.
1166 pub fn to_async(&self) -> AsyncWindowContext {
1167 AsyncWindowContext::new(self.app.to_async(), self.window.handle)
1168 }
1169
1170 /// Schedule the given closure to be run directly after the current frame is rendered.
1171 pub fn on_next_frame(&mut self, callback: impl FnOnce(&mut WindowContext) + 'static) {
1172 RefCell::borrow_mut(&self.window.next_frame_callbacks).push(Box::new(callback));
1173 }
1174
1175 /// Spawn the future returned by the given closure on the application thread pool.
1176 /// The closure is provided a handle to the current window and an `AsyncWindowContext` for
1177 /// use within your future.
1178 pub fn spawn<Fut, R>(&mut self, f: impl FnOnce(AsyncWindowContext) -> Fut) -> Task<R>
1179 where
1180 R: 'static,
1181 Fut: Future<Output = R> + 'static,
1182 {
1183 self.app
1184 .spawn(|app| f(AsyncWindowContext::new(app, self.window.handle)))
1185 }
1186
1187 fn bounds_changed(&mut self) {
1188 self.window.scale_factor = self.window.platform_window.scale_factor();
1189 self.window.viewport_size = self.window.platform_window.content_size();
1190 self.window.display_id = self
1191 .window
1192 .platform_window
1193 .display()
1194 .map(|display| display.id());
1195
1196 self.refresh();
1197
1198 self.window
1199 .bounds_observers
1200 .clone()
1201 .retain(&(), |callback| callback(self));
1202 }
1203
1204 /// Returns the bounds of the current window in the global coordinate space, which could span across multiple displays.
1205 pub fn bounds(&self) -> Bounds<Pixels> {
1206 self.window.platform_window.bounds()
1207 }
1208
1209 /// Returns whether or not the window is currently fullscreen
1210 pub fn is_fullscreen(&self) -> bool {
1211 self.window.platform_window.is_fullscreen()
1212 }
1213
1214 pub(crate) fn appearance_changed(&mut self) {
1215 self.window.appearance = self.window.platform_window.appearance();
1216
1217 self.window
1218 .appearance_observers
1219 .clone()
1220 .retain(&(), |callback| callback(self));
1221 }
1222
1223 /// Returns the appearance of the current window.
1224 pub fn appearance(&self) -> WindowAppearance {
1225 self.window.appearance
1226 }
1227
1228 /// Returns the size of the drawable area within the window.
1229 pub fn viewport_size(&self) -> Size<Pixels> {
1230 self.window.viewport_size
1231 }
1232
1233 /// Returns whether this window is focused by the operating system (receiving key events).
1234 pub fn is_window_active(&self) -> bool {
1235 self.window.active.get()
1236 }
1237
1238 /// Returns whether this window is considered to be the window
1239 /// that currently owns the mouse cursor.
1240 /// On mac, this is equivalent to `is_window_active`.
1241 pub fn is_window_hovered(&self) -> bool {
1242 if cfg!(target_os = "linux") {
1243 self.window.hovered.get()
1244 } else {
1245 self.is_window_active()
1246 }
1247 }
1248
1249 /// Toggle zoom on the window.
1250 pub fn zoom_window(&self) {
1251 self.window.platform_window.zoom();
1252 }
1253
1254 /// Opens the native title bar context menu, useful when implementing client side decorations (Wayland and X11)
1255 pub fn show_window_menu(&self, position: Point<Pixels>) {
1256 self.window.platform_window.show_window_menu(position)
1257 }
1258
1259 /// Tells the compositor to take control of window movement (Wayland and X11)
1260 ///
1261 /// Events may not be received during a move operation.
1262 pub fn start_window_move(&self) {
1263 self.window.platform_window.start_window_move()
1264 }
1265
1266 /// When using client side decorations, set this to the width of the invisible decorations (Wayland and X11)
1267 pub fn set_client_inset(&self, inset: Pixels) {
1268 self.window.platform_window.set_client_inset(inset);
1269 }
1270
1271 /// Returns whether the title bar window controls need to be rendered by the application (Wayland and X11)
1272 pub fn window_decorations(&self) -> Decorations {
1273 self.window.platform_window.window_decorations()
1274 }
1275
1276 /// Returns which window controls are currently visible (Wayland)
1277 pub fn window_controls(&self) -> WindowControls {
1278 self.window.platform_window.window_controls()
1279 }
1280
1281 /// Updates the window's title at the platform level.
1282 pub fn set_window_title(&mut self, title: &str) {
1283 self.window.platform_window.set_title(title);
1284 }
1285
1286 /// Sets the application identifier.
1287 pub fn set_app_id(&mut self, app_id: &str) {
1288 self.window.platform_window.set_app_id(app_id);
1289 }
1290
1291 /// Sets the window background appearance.
1292 pub fn set_background_appearance(&self, background_appearance: WindowBackgroundAppearance) {
1293 self.window
1294 .platform_window
1295 .set_background_appearance(background_appearance);
1296 }
1297
1298 /// Mark the window as dirty at the platform level.
1299 pub fn set_window_edited(&mut self, edited: bool) {
1300 self.window.platform_window.set_edited(edited);
1301 }
1302
1303 /// Determine the display on which the window is visible.
1304 pub fn display(&self) -> Option<Rc<dyn PlatformDisplay>> {
1305 self.platform
1306 .displays()
1307 .into_iter()
1308 .find(|display| Some(display.id()) == self.window.display_id)
1309 }
1310
1311 /// Show the platform character palette.
1312 pub fn show_character_palette(&self) {
1313 self.window.platform_window.show_character_palette();
1314 }
1315
1316 /// The scale factor of the display associated with the window. For example, it could
1317 /// return 2.0 for a "retina" display, indicating that each logical pixel should actually
1318 /// be rendered as two pixels on screen.
1319 pub fn scale_factor(&self) -> f32 {
1320 self.window.scale_factor
1321 }
1322
1323 /// The size of an em for the base font of the application. Adjusting this value allows the
1324 /// UI to scale, just like zooming a web page.
1325 pub fn rem_size(&self) -> Pixels {
1326 self.window
1327 .rem_size_override_stack
1328 .last()
1329 .copied()
1330 .unwrap_or(self.window.rem_size)
1331 }
1332
1333 /// Sets the size of an em for the base font of the application. Adjusting this value allows the
1334 /// UI to scale, just like zooming a web page.
1335 pub fn set_rem_size(&mut self, rem_size: impl Into<Pixels>) {
1336 self.window.rem_size = rem_size.into();
1337 }
1338
1339 /// Executes the provided function with the specified rem size.
1340 ///
1341 /// This method must only be called as part of element drawing.
1342 pub fn with_rem_size<F, R>(&mut self, rem_size: Option<impl Into<Pixels>>, f: F) -> R
1343 where
1344 F: FnOnce(&mut Self) -> R,
1345 {
1346 debug_assert!(
1347 matches!(
1348 self.window.draw_phase,
1349 DrawPhase::Prepaint | DrawPhase::Paint
1350 ),
1351 "this method can only be called during request_layout, prepaint, or paint"
1352 );
1353
1354 if let Some(rem_size) = rem_size {
1355 self.window.rem_size_override_stack.push(rem_size.into());
1356 let result = f(self);
1357 self.window.rem_size_override_stack.pop();
1358 result
1359 } else {
1360 f(self)
1361 }
1362 }
1363
1364 /// The line height associated with the current text style.
1365 pub fn line_height(&self) -> Pixels {
1366 let rem_size = self.rem_size();
1367 let text_style = self.text_style();
1368 text_style
1369 .line_height
1370 .to_pixels(text_style.font_size, rem_size)
1371 }
1372
1373 /// Call to prevent the default action of an event. Currently only used to prevent
1374 /// parent elements from becoming focused on mouse down.
1375 pub fn prevent_default(&mut self) {
1376 self.window.default_prevented = true;
1377 }
1378
1379 /// Obtain whether default has been prevented for the event currently being dispatched.
1380 pub fn default_prevented(&self) -> bool {
1381 self.window.default_prevented
1382 }
1383
1384 /// Determine whether the given action is available along the dispatch path to the currently focused element.
1385 pub fn is_action_available(&self, action: &dyn Action) -> bool {
1386 let target = self
1387 .focused()
1388 .and_then(|focused_handle| {
1389 self.window
1390 .rendered_frame
1391 .dispatch_tree
1392 .focusable_node_id(focused_handle.id)
1393 })
1394 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
1395 self.window
1396 .rendered_frame
1397 .dispatch_tree
1398 .is_action_available(action, target)
1399 }
1400
1401 /// The position of the mouse relative to the window.
1402 pub fn mouse_position(&self) -> Point<Pixels> {
1403 self.window.mouse_position
1404 }
1405
1406 /// The current state of the keyboard's modifiers
1407 pub fn modifiers(&self) -> Modifiers {
1408 self.window.modifiers
1409 }
1410
1411 fn complete_frame(&self) {
1412 self.window.platform_window.completed_frame();
1413 }
1414
1415 /// Produces a new frame and assigns it to `rendered_frame`. To actually show
1416 /// the contents of the new [Scene], use [present].
1417 #[profiling::function]
1418 pub fn draw(&mut self) {
1419 self.window.dirty.set(false);
1420 self.window.requested_autoscroll = None;
1421
1422 // Restore the previously-used input handler.
1423 if let Some(input_handler) = self.window.platform_window.take_input_handler() {
1424 self.window
1425 .rendered_frame
1426 .input_handlers
1427 .push(Some(input_handler));
1428 }
1429
1430 self.draw_roots();
1431 self.window.dirty_views.clear();
1432
1433 self.window
1434 .next_frame
1435 .dispatch_tree
1436 .preserve_pending_keystrokes(
1437 &mut self.window.rendered_frame.dispatch_tree,
1438 self.window.focus,
1439 );
1440 self.window.next_frame.focus = self.window.focus;
1441 self.window.next_frame.window_active = self.window.active.get();
1442
1443 // Register requested input handler with the platform window.
1444 if let Some(input_handler) = self.window.next_frame.input_handlers.pop() {
1445 self.window
1446 .platform_window
1447 .set_input_handler(input_handler.unwrap());
1448 }
1449
1450 self.window.layout_engine.as_mut().unwrap().clear();
1451 self.text_system().finish_frame();
1452 self.window
1453 .next_frame
1454 .finish(&mut self.window.rendered_frame);
1455 ELEMENT_ARENA.with_borrow_mut(|element_arena| {
1456 let percentage = (element_arena.len() as f32 / element_arena.capacity() as f32) * 100.;
1457 if percentage >= 80. {
1458 log::warn!("elevated element arena occupation: {}.", percentage);
1459 }
1460 element_arena.clear();
1461 });
1462
1463 self.window.draw_phase = DrawPhase::Focus;
1464 let previous_focus_path = self.window.rendered_frame.focus_path();
1465 let previous_window_active = self.window.rendered_frame.window_active;
1466 mem::swap(&mut self.window.rendered_frame, &mut self.window.next_frame);
1467 self.window.next_frame.clear();
1468 let current_focus_path = self.window.rendered_frame.focus_path();
1469 let current_window_active = self.window.rendered_frame.window_active;
1470
1471 if previous_focus_path != current_focus_path
1472 || previous_window_active != current_window_active
1473 {
1474 if !previous_focus_path.is_empty() && current_focus_path.is_empty() {
1475 self.window
1476 .focus_lost_listeners
1477 .clone()
1478 .retain(&(), |listener| listener(self));
1479 }
1480
1481 let event = WindowFocusEvent {
1482 previous_focus_path: if previous_window_active {
1483 previous_focus_path
1484 } else {
1485 Default::default()
1486 },
1487 current_focus_path: if current_window_active {
1488 current_focus_path
1489 } else {
1490 Default::default()
1491 },
1492 };
1493 self.window
1494 .focus_listeners
1495 .clone()
1496 .retain(&(), |listener| listener(&event, self));
1497 }
1498
1499 self.reset_cursor_style();
1500 self.window.refreshing = false;
1501 self.window.draw_phase = DrawPhase::None;
1502 self.window.needs_present.set(true);
1503 }
1504
1505 #[profiling::function]
1506 fn present(&self) {
1507 self.window
1508 .platform_window
1509 .draw(&self.window.rendered_frame.scene);
1510 self.window.needs_present.set(false);
1511 profiling::finish_frame!();
1512 }
1513
1514 fn draw_roots(&mut self) {
1515 self.window.draw_phase = DrawPhase::Prepaint;
1516 self.window.tooltip_bounds.take();
1517
1518 // Layout all root elements.
1519 let mut root_element = self.window.root_view.as_ref().unwrap().clone().into_any();
1520 root_element.prepaint_as_root(Point::default(), self.window.viewport_size.into(), self);
1521
1522 let mut sorted_deferred_draws =
1523 (0..self.window.next_frame.deferred_draws.len()).collect::<SmallVec<[_; 8]>>();
1524 sorted_deferred_draws.sort_by_key(|ix| self.window.next_frame.deferred_draws[*ix].priority);
1525 self.prepaint_deferred_draws(&sorted_deferred_draws);
1526
1527 let mut prompt_element = None;
1528 let mut active_drag_element = None;
1529 let mut tooltip_element = None;
1530 if let Some(prompt) = self.window.prompt.take() {
1531 let mut element = prompt.view.any_view().into_any();
1532 element.prepaint_as_root(Point::default(), self.window.viewport_size.into(), self);
1533 prompt_element = Some(element);
1534 self.window.prompt = Some(prompt);
1535 } else if let Some(active_drag) = self.app.active_drag.take() {
1536 let mut element = active_drag.view.clone().into_any();
1537 let offset = self.mouse_position() - active_drag.cursor_offset;
1538 element.prepaint_as_root(offset, AvailableSpace::min_size(), self);
1539 active_drag_element = Some(element);
1540 self.app.active_drag = Some(active_drag);
1541 } else {
1542 tooltip_element = self.prepaint_tooltip();
1543 }
1544
1545 self.window.mouse_hit_test = self.window.next_frame.hit_test(self.window.mouse_position);
1546
1547 // Now actually paint the elements.
1548 self.window.draw_phase = DrawPhase::Paint;
1549 root_element.paint(self);
1550
1551 self.paint_deferred_draws(&sorted_deferred_draws);
1552
1553 if let Some(mut prompt_element) = prompt_element {
1554 prompt_element.paint(self)
1555 } else if let Some(mut drag_element) = active_drag_element {
1556 drag_element.paint(self);
1557 } else if let Some(mut tooltip_element) = tooltip_element {
1558 tooltip_element.paint(self);
1559 }
1560 }
1561
1562 fn prepaint_tooltip(&mut self) -> Option<AnyElement> {
1563 let tooltip_request = self.window.next_frame.tooltip_requests.last().cloned()?;
1564 let tooltip_request = tooltip_request.unwrap();
1565 let mut element = tooltip_request.tooltip.view.clone().into_any();
1566 let mouse_position = tooltip_request.tooltip.mouse_position;
1567 let tooltip_size = element.layout_as_root(AvailableSpace::min_size(), self);
1568
1569 let mut tooltip_bounds = Bounds::new(mouse_position + point(px(1.), px(1.)), tooltip_size);
1570 let window_bounds = Bounds {
1571 origin: Point::default(),
1572 size: self.viewport_size(),
1573 };
1574
1575 if tooltip_bounds.right() > window_bounds.right() {
1576 let new_x = mouse_position.x - tooltip_bounds.size.width - px(1.);
1577 if new_x >= Pixels::ZERO {
1578 tooltip_bounds.origin.x = new_x;
1579 } else {
1580 tooltip_bounds.origin.x = cmp::max(
1581 Pixels::ZERO,
1582 tooltip_bounds.origin.x - tooltip_bounds.right() - window_bounds.right(),
1583 );
1584 }
1585 }
1586
1587 if tooltip_bounds.bottom() > window_bounds.bottom() {
1588 let new_y = mouse_position.y - tooltip_bounds.size.height - px(1.);
1589 if new_y >= Pixels::ZERO {
1590 tooltip_bounds.origin.y = new_y;
1591 } else {
1592 tooltip_bounds.origin.y = cmp::max(
1593 Pixels::ZERO,
1594 tooltip_bounds.origin.y - tooltip_bounds.bottom() - window_bounds.bottom(),
1595 );
1596 }
1597 }
1598
1599 self.with_absolute_element_offset(tooltip_bounds.origin, |cx| element.prepaint(cx));
1600
1601 self.window.tooltip_bounds = Some(TooltipBounds {
1602 id: tooltip_request.id,
1603 bounds: tooltip_bounds,
1604 });
1605 Some(element)
1606 }
1607
1608 fn prepaint_deferred_draws(&mut self, deferred_draw_indices: &[usize]) {
1609 assert_eq!(self.window.element_id_stack.len(), 0);
1610
1611 let mut deferred_draws = mem::take(&mut self.window.next_frame.deferred_draws);
1612 for deferred_draw_ix in deferred_draw_indices {
1613 let deferred_draw = &mut deferred_draws[*deferred_draw_ix];
1614 self.window
1615 .element_id_stack
1616 .clone_from(&deferred_draw.element_id_stack);
1617 self.window
1618 .text_style_stack
1619 .clone_from(&deferred_draw.text_style_stack);
1620 self.window
1621 .next_frame
1622 .dispatch_tree
1623 .set_active_node(deferred_draw.parent_node);
1624
1625 let prepaint_start = self.prepaint_index();
1626 if let Some(element) = deferred_draw.element.as_mut() {
1627 self.with_absolute_element_offset(deferred_draw.absolute_offset, |cx| {
1628 element.prepaint(cx)
1629 });
1630 } else {
1631 self.reuse_prepaint(deferred_draw.prepaint_range.clone());
1632 }
1633 let prepaint_end = self.prepaint_index();
1634 deferred_draw.prepaint_range = prepaint_start..prepaint_end;
1635 }
1636 assert_eq!(
1637 self.window.next_frame.deferred_draws.len(),
1638 0,
1639 "cannot call defer_draw during deferred drawing"
1640 );
1641 self.window.next_frame.deferred_draws = deferred_draws;
1642 self.window.element_id_stack.clear();
1643 self.window.text_style_stack.clear();
1644 }
1645
1646 fn paint_deferred_draws(&mut self, deferred_draw_indices: &[usize]) {
1647 assert_eq!(self.window.element_id_stack.len(), 0);
1648
1649 let mut deferred_draws = mem::take(&mut self.window.next_frame.deferred_draws);
1650 for deferred_draw_ix in deferred_draw_indices {
1651 let mut deferred_draw = &mut deferred_draws[*deferred_draw_ix];
1652 self.window
1653 .element_id_stack
1654 .clone_from(&deferred_draw.element_id_stack);
1655 self.window
1656 .next_frame
1657 .dispatch_tree
1658 .set_active_node(deferred_draw.parent_node);
1659
1660 let paint_start = self.paint_index();
1661 if let Some(element) = deferred_draw.element.as_mut() {
1662 element.paint(self);
1663 } else {
1664 self.reuse_paint(deferred_draw.paint_range.clone());
1665 }
1666 let paint_end = self.paint_index();
1667 deferred_draw.paint_range = paint_start..paint_end;
1668 }
1669 self.window.next_frame.deferred_draws = deferred_draws;
1670 self.window.element_id_stack.clear();
1671 }
1672
1673 pub(crate) fn prepaint_index(&self) -> PrepaintStateIndex {
1674 PrepaintStateIndex {
1675 hitboxes_index: self.window.next_frame.hitboxes.len(),
1676 tooltips_index: self.window.next_frame.tooltip_requests.len(),
1677 deferred_draws_index: self.window.next_frame.deferred_draws.len(),
1678 dispatch_tree_index: self.window.next_frame.dispatch_tree.len(),
1679 accessed_element_states_index: self.window.next_frame.accessed_element_states.len(),
1680 line_layout_index: self.window.text_system.layout_index(),
1681 }
1682 }
1683
1684 pub(crate) fn reuse_prepaint(&mut self, range: Range<PrepaintStateIndex>) {
1685 let window = &mut self.window;
1686 window.next_frame.hitboxes.extend(
1687 window.rendered_frame.hitboxes[range.start.hitboxes_index..range.end.hitboxes_index]
1688 .iter()
1689 .cloned(),
1690 );
1691 window.next_frame.tooltip_requests.extend(
1692 window.rendered_frame.tooltip_requests
1693 [range.start.tooltips_index..range.end.tooltips_index]
1694 .iter_mut()
1695 .map(|request| request.take()),
1696 );
1697 window.next_frame.accessed_element_states.extend(
1698 window.rendered_frame.accessed_element_states[range.start.accessed_element_states_index
1699 ..range.end.accessed_element_states_index]
1700 .iter()
1701 .map(|(id, type_id)| (GlobalElementId(id.0.clone()), *type_id)),
1702 );
1703 window
1704 .text_system
1705 .reuse_layouts(range.start.line_layout_index..range.end.line_layout_index);
1706
1707 let reused_subtree = window.next_frame.dispatch_tree.reuse_subtree(
1708 range.start.dispatch_tree_index..range.end.dispatch_tree_index,
1709 &mut window.rendered_frame.dispatch_tree,
1710 );
1711 window.next_frame.deferred_draws.extend(
1712 window.rendered_frame.deferred_draws
1713 [range.start.deferred_draws_index..range.end.deferred_draws_index]
1714 .iter()
1715 .map(|deferred_draw| DeferredDraw {
1716 parent_node: reused_subtree.refresh_node_id(deferred_draw.parent_node),
1717 element_id_stack: deferred_draw.element_id_stack.clone(),
1718 text_style_stack: deferred_draw.text_style_stack.clone(),
1719 priority: deferred_draw.priority,
1720 element: None,
1721 absolute_offset: deferred_draw.absolute_offset,
1722 prepaint_range: deferred_draw.prepaint_range.clone(),
1723 paint_range: deferred_draw.paint_range.clone(),
1724 }),
1725 );
1726 }
1727
1728 pub(crate) fn paint_index(&self) -> PaintIndex {
1729 PaintIndex {
1730 scene_index: self.window.next_frame.scene.len(),
1731 mouse_listeners_index: self.window.next_frame.mouse_listeners.len(),
1732 input_handlers_index: self.window.next_frame.input_handlers.len(),
1733 cursor_styles_index: self.window.next_frame.cursor_styles.len(),
1734 accessed_element_states_index: self.window.next_frame.accessed_element_states.len(),
1735 line_layout_index: self.window.text_system.layout_index(),
1736 }
1737 }
1738
1739 pub(crate) fn reuse_paint(&mut self, range: Range<PaintIndex>) {
1740 let window = &mut self.window;
1741
1742 window.next_frame.cursor_styles.extend(
1743 window.rendered_frame.cursor_styles
1744 [range.start.cursor_styles_index..range.end.cursor_styles_index]
1745 .iter()
1746 .cloned(),
1747 );
1748 window.next_frame.input_handlers.extend(
1749 window.rendered_frame.input_handlers
1750 [range.start.input_handlers_index..range.end.input_handlers_index]
1751 .iter_mut()
1752 .map(|handler| handler.take()),
1753 );
1754 window.next_frame.mouse_listeners.extend(
1755 window.rendered_frame.mouse_listeners
1756 [range.start.mouse_listeners_index..range.end.mouse_listeners_index]
1757 .iter_mut()
1758 .map(|listener| listener.take()),
1759 );
1760 window.next_frame.accessed_element_states.extend(
1761 window.rendered_frame.accessed_element_states[range.start.accessed_element_states_index
1762 ..range.end.accessed_element_states_index]
1763 .iter()
1764 .map(|(id, type_id)| (GlobalElementId(id.0.clone()), *type_id)),
1765 );
1766 window
1767 .text_system
1768 .reuse_layouts(range.start.line_layout_index..range.end.line_layout_index);
1769 window.next_frame.scene.replay(
1770 range.start.scene_index..range.end.scene_index,
1771 &window.rendered_frame.scene,
1772 );
1773 }
1774
1775 /// Push a text style onto the stack, and call a function with that style active.
1776 /// Use [`AppContext::text_style`] to get the current, combined text style. This method
1777 /// should only be called as part of element drawing.
1778 pub fn with_text_style<F, R>(&mut self, style: Option<TextStyleRefinement>, f: F) -> R
1779 where
1780 F: FnOnce(&mut Self) -> R,
1781 {
1782 debug_assert!(
1783 matches!(
1784 self.window.draw_phase,
1785 DrawPhase::Prepaint | DrawPhase::Paint
1786 ),
1787 "this method can only be called during request_layout, prepaint, or paint"
1788 );
1789 if let Some(style) = style {
1790 self.window.text_style_stack.push(style);
1791 let result = f(self);
1792 self.window.text_style_stack.pop();
1793 result
1794 } else {
1795 f(self)
1796 }
1797 }
1798
1799 /// Updates the cursor style at the platform level. This method should only be called
1800 /// during the prepaint phase of element drawing.
1801 pub fn set_cursor_style(&mut self, style: CursorStyle, hitbox: &Hitbox) {
1802 debug_assert_eq!(
1803 self.window.draw_phase,
1804 DrawPhase::Paint,
1805 "this method can only be called during paint"
1806 );
1807 self.window
1808 .next_frame
1809 .cursor_styles
1810 .push(CursorStyleRequest {
1811 hitbox_id: hitbox.id,
1812 style,
1813 });
1814 }
1815
1816 /// Sets a tooltip to be rendered for the upcoming frame. This method should only be called
1817 /// during the paint phase of element drawing.
1818 pub fn set_tooltip(&mut self, tooltip: AnyTooltip) -> TooltipId {
1819 debug_assert_eq!(
1820 self.window.draw_phase,
1821 DrawPhase::Prepaint,
1822 "this method can only be called during prepaint"
1823 );
1824 let id = TooltipId(post_inc(&mut self.window.next_tooltip_id.0));
1825 self.window
1826 .next_frame
1827 .tooltip_requests
1828 .push(Some(TooltipRequest { id, tooltip }));
1829 id
1830 }
1831
1832 /// Invoke the given function with the given content mask after intersecting it
1833 /// with the current mask. This method should only be called during element drawing.
1834 pub fn with_content_mask<R>(
1835 &mut self,
1836 mask: Option<ContentMask<Pixels>>,
1837 f: impl FnOnce(&mut Self) -> R,
1838 ) -> R {
1839 debug_assert!(
1840 matches!(
1841 self.window.draw_phase,
1842 DrawPhase::Prepaint | DrawPhase::Paint
1843 ),
1844 "this method can only be called during request_layout, prepaint, or paint"
1845 );
1846 if let Some(mask) = mask {
1847 let mask = mask.intersect(&self.content_mask());
1848 self.window_mut().content_mask_stack.push(mask);
1849 let result = f(self);
1850 self.window_mut().content_mask_stack.pop();
1851 result
1852 } else {
1853 f(self)
1854 }
1855 }
1856
1857 /// Updates the global element offset relative to the current offset. This is used to implement
1858 /// scrolling. This method should only be called during the prepaint phase of element drawing.
1859 pub fn with_element_offset<R>(
1860 &mut self,
1861 offset: Point<Pixels>,
1862 f: impl FnOnce(&mut Self) -> R,
1863 ) -> R {
1864 debug_assert_eq!(
1865 self.window.draw_phase,
1866 DrawPhase::Prepaint,
1867 "this method can only be called during request_layout, or prepaint"
1868 );
1869
1870 if offset.is_zero() {
1871 return f(self);
1872 };
1873
1874 let abs_offset = self.element_offset() + offset;
1875 self.with_absolute_element_offset(abs_offset, f)
1876 }
1877
1878 /// Updates the global element offset based on the given offset. This is used to implement
1879 /// drag handles and other manual painting of elements. This method should only be called during
1880 /// the prepaint phase of element drawing.
1881 pub fn with_absolute_element_offset<R>(
1882 &mut self,
1883 offset: Point<Pixels>,
1884 f: impl FnOnce(&mut Self) -> R,
1885 ) -> R {
1886 debug_assert_eq!(
1887 self.window.draw_phase,
1888 DrawPhase::Prepaint,
1889 "this method can only be called during request_layout, or prepaint"
1890 );
1891 self.window_mut().element_offset_stack.push(offset);
1892 let result = f(self);
1893 self.window_mut().element_offset_stack.pop();
1894 result
1895 }
1896
1897 /// Perform prepaint on child elements in a "retryable" manner, so that any side effects
1898 /// of prepaints can be discarded before prepainting again. This is used to support autoscroll
1899 /// where we need to prepaint children to detect the autoscroll bounds, then adjust the
1900 /// element offset and prepaint again. See [`List`] for an example. This method should only be
1901 /// called during the prepaint phase of element drawing.
1902 pub fn transact<T, U>(&mut self, f: impl FnOnce(&mut Self) -> Result<T, U>) -> Result<T, U> {
1903 debug_assert_eq!(
1904 self.window.draw_phase,
1905 DrawPhase::Prepaint,
1906 "this method can only be called during prepaint"
1907 );
1908 let index = self.prepaint_index();
1909 let result = f(self);
1910 if result.is_err() {
1911 self.window
1912 .next_frame
1913 .hitboxes
1914 .truncate(index.hitboxes_index);
1915 self.window
1916 .next_frame
1917 .tooltip_requests
1918 .truncate(index.tooltips_index);
1919 self.window
1920 .next_frame
1921 .deferred_draws
1922 .truncate(index.deferred_draws_index);
1923 self.window
1924 .next_frame
1925 .dispatch_tree
1926 .truncate(index.dispatch_tree_index);
1927 self.window
1928 .next_frame
1929 .accessed_element_states
1930 .truncate(index.accessed_element_states_index);
1931 self.window
1932 .text_system
1933 .truncate_layouts(index.line_layout_index);
1934 }
1935 result
1936 }
1937
1938 /// When you call this method during [`prepaint`], containing elements will attempt to
1939 /// scroll to cause the specified bounds to become visible. When they decide to autoscroll, they will call
1940 /// [`prepaint`] again with a new set of bounds. See [`List`] for an example of an element
1941 /// that supports this method being called on the elements it contains. This method should only be
1942 /// called during the prepaint phase of element drawing.
1943 pub fn request_autoscroll(&mut self, bounds: Bounds<Pixels>) {
1944 debug_assert_eq!(
1945 self.window.draw_phase,
1946 DrawPhase::Prepaint,
1947 "this method can only be called during prepaint"
1948 );
1949 self.window.requested_autoscroll = Some(bounds);
1950 }
1951
1952 /// This method can be called from a containing element such as [`List`] to support the autoscroll behavior
1953 /// described in [`request_autoscroll`].
1954 pub fn take_autoscroll(&mut self) -> Option<Bounds<Pixels>> {
1955 debug_assert_eq!(
1956 self.window.draw_phase,
1957 DrawPhase::Prepaint,
1958 "this method can only be called during prepaint"
1959 );
1960 self.window.requested_autoscroll.take()
1961 }
1962
1963 /// Remove an asset from GPUI's cache
1964 pub fn remove_cached_asset<A: Asset + 'static>(
1965 &mut self,
1966 source: &A::Source,
1967 ) -> Option<A::Output> {
1968 self.asset_cache.remove::<A>(source)
1969 }
1970
1971 /// Asynchronously load an asset, if the asset hasn't finished loading this will return None.
1972 /// Your view will be re-drawn once the asset has finished loading.
1973 ///
1974 /// Note that the multiple calls to this method will only result in one `Asset::load` call.
1975 /// The results of that call will be cached, and returned on subsequent uses of this API.
1976 ///
1977 /// Use [Self::remove_cached_asset] to reload your asset.
1978 pub fn use_cached_asset<A: Asset + 'static>(
1979 &mut self,
1980 source: &A::Source,
1981 ) -> Option<A::Output> {
1982 self.asset_cache.get::<A>(source).or_else(|| {
1983 if let Some(asset) = self.use_asset::<A>(source) {
1984 self.asset_cache
1985 .insert::<A>(source.to_owned(), asset.clone());
1986 Some(asset)
1987 } else {
1988 None
1989 }
1990 })
1991 }
1992
1993 /// Asynchronously load an asset, if the asset hasn't finished loading this will return None.
1994 /// Your view will be re-drawn once the asset has finished loading.
1995 ///
1996 /// Note that the multiple calls to this method will only result in one `Asset::load` call at a
1997 /// time.
1998 ///
1999 /// This asset will not be cached by default, see [Self::use_cached_asset]
2000 pub fn use_asset<A: Asset + 'static>(&mut self, source: &A::Source) -> Option<A::Output> {
2001 let asset_id = (TypeId::of::<A>(), hash(source));
2002 let mut is_first = false;
2003 let task = self
2004 .loading_assets
2005 .remove(&asset_id)
2006 .map(|boxed_task| *boxed_task.downcast::<Shared<Task<A::Output>>>().unwrap())
2007 .unwrap_or_else(|| {
2008 is_first = true;
2009 let future = A::load(source.clone(), self);
2010 let task = self.background_executor().spawn(future).shared();
2011 task
2012 });
2013
2014 task.clone().now_or_never().or_else(|| {
2015 if is_first {
2016 let parent_id = self.parent_view_id();
2017 self.spawn({
2018 let task = task.clone();
2019 |mut cx| async move {
2020 task.await;
2021
2022 cx.on_next_frame(move |cx| {
2023 if let Some(parent_id) = parent_id {
2024 cx.notify(parent_id)
2025 } else {
2026 cx.refresh()
2027 }
2028 });
2029 }
2030 })
2031 .detach();
2032 }
2033
2034 self.loading_assets.insert(asset_id, Box::new(task));
2035
2036 None
2037 })
2038 }
2039
2040 /// Obtain the current element offset. This method should only be called during the
2041 /// prepaint phase of element drawing.
2042 pub fn element_offset(&self) -> Point<Pixels> {
2043 debug_assert_eq!(
2044 self.window.draw_phase,
2045 DrawPhase::Prepaint,
2046 "this method can only be called during prepaint"
2047 );
2048 self.window()
2049 .element_offset_stack
2050 .last()
2051 .copied()
2052 .unwrap_or_default()
2053 }
2054
2055 /// Obtain the current content mask. This method should only be called during element drawing.
2056 pub fn content_mask(&self) -> ContentMask<Pixels> {
2057 debug_assert!(
2058 matches!(
2059 self.window.draw_phase,
2060 DrawPhase::Prepaint | DrawPhase::Paint
2061 ),
2062 "this method can only be called during prepaint, or paint"
2063 );
2064 self.window()
2065 .content_mask_stack
2066 .last()
2067 .cloned()
2068 .unwrap_or_else(|| ContentMask {
2069 bounds: Bounds {
2070 origin: Point::default(),
2071 size: self.window().viewport_size,
2072 },
2073 })
2074 }
2075
2076 /// Provide elements in the called function with a new namespace in which their identiers must be unique.
2077 /// This can be used within a custom element to distinguish multiple sets of child elements.
2078 pub fn with_element_namespace<R>(
2079 &mut self,
2080 element_id: impl Into<ElementId>,
2081 f: impl FnOnce(&mut Self) -> R,
2082 ) -> R {
2083 self.window.element_id_stack.push(element_id.into());
2084 let result = f(self);
2085 self.window.element_id_stack.pop();
2086 result
2087 }
2088
2089 /// Updates or initializes state for an element with the given id that lives across multiple
2090 /// frames. If an element with this ID existed in the rendered frame, its state will be passed
2091 /// to the given closure. The state returned by the closure will be stored so it can be referenced
2092 /// when drawing the next frame. This method should only be called as part of element drawing.
2093 pub fn with_element_state<S, R>(
2094 &mut self,
2095 global_id: &GlobalElementId,
2096 f: impl FnOnce(Option<S>, &mut Self) -> (R, S),
2097 ) -> R
2098 where
2099 S: 'static,
2100 {
2101 debug_assert!(
2102 matches!(
2103 self.window.draw_phase,
2104 DrawPhase::Prepaint | DrawPhase::Paint
2105 ),
2106 "this method can only be called during request_layout, prepaint, or paint"
2107 );
2108
2109 let key = (GlobalElementId(global_id.0.clone()), TypeId::of::<S>());
2110 self.window
2111 .next_frame
2112 .accessed_element_states
2113 .push((GlobalElementId(key.0.clone()), TypeId::of::<S>()));
2114
2115 if let Some(any) = self
2116 .window
2117 .next_frame
2118 .element_states
2119 .remove(&key)
2120 .or_else(|| self.window.rendered_frame.element_states.remove(&key))
2121 {
2122 let ElementStateBox {
2123 inner,
2124 #[cfg(debug_assertions)]
2125 type_name,
2126 } = any;
2127 // Using the extra inner option to avoid needing to reallocate a new box.
2128 let mut state_box = inner
2129 .downcast::<Option<S>>()
2130 .map_err(|_| {
2131 #[cfg(debug_assertions)]
2132 {
2133 anyhow::anyhow!(
2134 "invalid element state type for id, requested {:?}, actual: {:?}",
2135 std::any::type_name::<S>(),
2136 type_name
2137 )
2138 }
2139
2140 #[cfg(not(debug_assertions))]
2141 {
2142 anyhow::anyhow!(
2143 "invalid element state type for id, requested {:?}",
2144 std::any::type_name::<S>(),
2145 )
2146 }
2147 })
2148 .unwrap();
2149
2150 let state = state_box.take().expect(
2151 "reentrant call to with_element_state for the same state type and element id",
2152 );
2153 let (result, state) = f(Some(state), self);
2154 state_box.replace(state);
2155 self.window.next_frame.element_states.insert(
2156 key,
2157 ElementStateBox {
2158 inner: state_box,
2159 #[cfg(debug_assertions)]
2160 type_name,
2161 },
2162 );
2163 result
2164 } else {
2165 let (result, state) = f(None, self);
2166 self.window.next_frame.element_states.insert(
2167 key,
2168 ElementStateBox {
2169 inner: Box::new(Some(state)),
2170 #[cfg(debug_assertions)]
2171 type_name: std::any::type_name::<S>(),
2172 },
2173 );
2174 result
2175 }
2176 }
2177
2178 /// A variant of `with_element_state` that allows the element's id to be optional. This is a convenience
2179 /// method for elements where the element id may or may not be assigned. Prefer using `with_element_state`
2180 /// when the element is guaranteed to have an id.
2181 pub fn with_optional_element_state<S, R>(
2182 &mut self,
2183 global_id: Option<&GlobalElementId>,
2184 f: impl FnOnce(Option<Option<S>>, &mut Self) -> (R, Option<S>),
2185 ) -> R
2186 where
2187 S: 'static,
2188 {
2189 debug_assert!(
2190 matches!(
2191 self.window.draw_phase,
2192 DrawPhase::Prepaint | DrawPhase::Paint
2193 ),
2194 "this method can only be called during request_layout, prepaint, or paint"
2195 );
2196
2197 if let Some(global_id) = global_id {
2198 self.with_element_state(global_id, |state, cx| {
2199 let (result, state) = f(Some(state), cx);
2200 let state =
2201 state.expect("you must return some state when you pass some element id");
2202 (result, state)
2203 })
2204 } else {
2205 let (result, state) = f(None, self);
2206 debug_assert!(
2207 state.is_none(),
2208 "you must not return an element state when passing None for the global id"
2209 );
2210 result
2211 }
2212 }
2213
2214 /// Defers the drawing of the given element, scheduling it to be painted on top of the currently-drawn tree
2215 /// at a later time. The `priority` parameter determines the drawing order relative to other deferred elements,
2216 /// with higher values being drawn on top.
2217 ///
2218 /// This method should only be called as part of the prepaint phase of element drawing.
2219 pub fn defer_draw(
2220 &mut self,
2221 element: AnyElement,
2222 absolute_offset: Point<Pixels>,
2223 priority: usize,
2224 ) {
2225 let window = &mut self.window;
2226 debug_assert_eq!(
2227 window.draw_phase,
2228 DrawPhase::Prepaint,
2229 "this method can only be called during request_layout or prepaint"
2230 );
2231 let parent_node = window.next_frame.dispatch_tree.active_node_id().unwrap();
2232 window.next_frame.deferred_draws.push(DeferredDraw {
2233 parent_node,
2234 element_id_stack: window.element_id_stack.clone(),
2235 text_style_stack: window.text_style_stack.clone(),
2236 priority,
2237 element: Some(element),
2238 absolute_offset,
2239 prepaint_range: PrepaintStateIndex::default()..PrepaintStateIndex::default(),
2240 paint_range: PaintIndex::default()..PaintIndex::default(),
2241 });
2242 }
2243
2244 /// Creates a new painting layer for the specified bounds. A "layer" is a batch
2245 /// of geometry that are non-overlapping and have the same draw order. This is typically used
2246 /// for performance reasons.
2247 ///
2248 /// This method should only be called as part of the paint phase of element drawing.
2249 pub fn paint_layer<R>(&mut self, bounds: Bounds<Pixels>, f: impl FnOnce(&mut Self) -> R) -> R {
2250 debug_assert_eq!(
2251 self.window.draw_phase,
2252 DrawPhase::Paint,
2253 "this method can only be called during paint"
2254 );
2255
2256 let scale_factor = self.scale_factor();
2257 let content_mask = self.content_mask();
2258 let clipped_bounds = bounds.intersect(&content_mask.bounds);
2259 if !clipped_bounds.is_empty() {
2260 self.window
2261 .next_frame
2262 .scene
2263 .push_layer(clipped_bounds.scale(scale_factor));
2264 }
2265
2266 let result = f(self);
2267
2268 if !clipped_bounds.is_empty() {
2269 self.window.next_frame.scene.pop_layer();
2270 }
2271
2272 result
2273 }
2274
2275 /// Paint one or more drop shadows into the scene for the next frame at the current z-index.
2276 ///
2277 /// This method should only be called as part of the paint phase of element drawing.
2278 pub fn paint_shadows(
2279 &mut self,
2280 bounds: Bounds<Pixels>,
2281 corner_radii: Corners<Pixels>,
2282 shadows: &[BoxShadow],
2283 ) {
2284 debug_assert_eq!(
2285 self.window.draw_phase,
2286 DrawPhase::Paint,
2287 "this method can only be called during paint"
2288 );
2289
2290 let scale_factor = self.scale_factor();
2291 let content_mask = self.content_mask();
2292 for shadow in shadows {
2293 let mut shadow_bounds = bounds;
2294 shadow_bounds.origin += shadow.offset;
2295 shadow_bounds.dilate(shadow.spread_radius);
2296 self.window.next_frame.scene.insert_primitive(Shadow {
2297 order: 0,
2298 blur_radius: shadow.blur_radius.scale(scale_factor),
2299 bounds: shadow_bounds.scale(scale_factor),
2300 content_mask: content_mask.scale(scale_factor),
2301 corner_radii: corner_radii.scale(scale_factor),
2302 color: shadow.color,
2303 });
2304 }
2305 }
2306
2307 /// Paint one or more quads into the scene for the next frame at the current stacking context.
2308 /// Quads are colored rectangular regions with an optional background, border, and corner radius.
2309 /// see [`fill`](crate::fill), [`outline`](crate::outline), and [`quad`](crate::quad) to construct this type.
2310 ///
2311 /// This method should only be called as part of the paint phase of element drawing.
2312 pub fn paint_quad(&mut self, quad: PaintQuad) {
2313 debug_assert_eq!(
2314 self.window.draw_phase,
2315 DrawPhase::Paint,
2316 "this method can only be called during paint"
2317 );
2318
2319 let scale_factor = self.scale_factor();
2320 let content_mask = self.content_mask();
2321 self.window.next_frame.scene.insert_primitive(Quad {
2322 order: 0,
2323 pad: 0,
2324 bounds: quad.bounds.scale(scale_factor),
2325 content_mask: content_mask.scale(scale_factor),
2326 background: quad.background,
2327 border_color: quad.border_color,
2328 corner_radii: quad.corner_radii.scale(scale_factor),
2329 border_widths: quad.border_widths.scale(scale_factor),
2330 });
2331 }
2332
2333 /// Paint the given `Path` into the scene for the next frame at the current z-index.
2334 ///
2335 /// This method should only be called as part of the paint phase of element drawing.
2336 pub fn paint_path(&mut self, mut path: Path<Pixels>, color: impl Into<Hsla>) {
2337 debug_assert_eq!(
2338 self.window.draw_phase,
2339 DrawPhase::Paint,
2340 "this method can only be called during paint"
2341 );
2342
2343 let scale_factor = self.scale_factor();
2344 let content_mask = self.content_mask();
2345 path.content_mask = content_mask;
2346 path.color = color.into();
2347 self.window
2348 .next_frame
2349 .scene
2350 .insert_primitive(path.scale(scale_factor));
2351 }
2352
2353 /// Paint an underline into the scene for the next frame at the current z-index.
2354 ///
2355 /// This method should only be called as part of the paint phase of element drawing.
2356 pub fn paint_underline(
2357 &mut self,
2358 origin: Point<Pixels>,
2359 width: Pixels,
2360 style: &UnderlineStyle,
2361 ) {
2362 debug_assert_eq!(
2363 self.window.draw_phase,
2364 DrawPhase::Paint,
2365 "this method can only be called during paint"
2366 );
2367
2368 let scale_factor = self.scale_factor();
2369 let height = if style.wavy {
2370 style.thickness * 3.
2371 } else {
2372 style.thickness
2373 };
2374 let bounds = Bounds {
2375 origin,
2376 size: size(width, height),
2377 };
2378 let content_mask = self.content_mask();
2379
2380 self.window.next_frame.scene.insert_primitive(Underline {
2381 order: 0,
2382 pad: 0,
2383 bounds: bounds.scale(scale_factor),
2384 content_mask: content_mask.scale(scale_factor),
2385 color: style.color.unwrap_or_default(),
2386 thickness: style.thickness.scale(scale_factor),
2387 wavy: style.wavy,
2388 });
2389 }
2390
2391 /// Paint a strikethrough into the scene for the next frame at the current z-index.
2392 ///
2393 /// This method should only be called as part of the paint phase of element drawing.
2394 pub fn paint_strikethrough(
2395 &mut self,
2396 origin: Point<Pixels>,
2397 width: Pixels,
2398 style: &StrikethroughStyle,
2399 ) {
2400 debug_assert_eq!(
2401 self.window.draw_phase,
2402 DrawPhase::Paint,
2403 "this method can only be called during paint"
2404 );
2405
2406 let scale_factor = self.scale_factor();
2407 let height = style.thickness;
2408 let bounds = Bounds {
2409 origin,
2410 size: size(width, height),
2411 };
2412 let content_mask = self.content_mask();
2413
2414 self.window.next_frame.scene.insert_primitive(Underline {
2415 order: 0,
2416 pad: 0,
2417 bounds: bounds.scale(scale_factor),
2418 content_mask: content_mask.scale(scale_factor),
2419 thickness: style.thickness.scale(scale_factor),
2420 color: style.color.unwrap_or_default(),
2421 wavy: false,
2422 });
2423 }
2424
2425 /// Paints a monochrome (non-emoji) glyph into the scene for the next frame at the current z-index.
2426 ///
2427 /// The y component of the origin is the baseline of the glyph.
2428 /// You should generally prefer to use the [`ShapedLine::paint`](crate::ShapedLine::paint) or
2429 /// [`WrappedLine::paint`](crate::WrappedLine::paint) methods in the [`TextSystem`](crate::TextSystem).
2430 /// This method is only useful if you need to paint a single glyph that has already been shaped.
2431 ///
2432 /// This method should only be called as part of the paint phase of element drawing.
2433 pub fn paint_glyph(
2434 &mut self,
2435 origin: Point<Pixels>,
2436 font_id: FontId,
2437 glyph_id: GlyphId,
2438 font_size: Pixels,
2439 color: Hsla,
2440 ) -> Result<()> {
2441 debug_assert_eq!(
2442 self.window.draw_phase,
2443 DrawPhase::Paint,
2444 "this method can only be called during paint"
2445 );
2446
2447 let scale_factor = self.scale_factor();
2448 let glyph_origin = origin.scale(scale_factor);
2449 let subpixel_variant = Point {
2450 x: (glyph_origin.x.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
2451 y: (glyph_origin.y.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
2452 };
2453 let params = RenderGlyphParams {
2454 font_id,
2455 glyph_id,
2456 font_size,
2457 subpixel_variant,
2458 scale_factor,
2459 is_emoji: false,
2460 };
2461
2462 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
2463 if !raster_bounds.is_zero() {
2464 let tile = self
2465 .window
2466 .sprite_atlas
2467 .get_or_insert_with(¶ms.clone().into(), &mut || {
2468 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
2469 Ok(Some((size, Cow::Owned(bytes))))
2470 })?
2471 .expect("Callback above only errors or returns Some");
2472 let bounds = Bounds {
2473 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
2474 size: tile.bounds.size.map(Into::into),
2475 };
2476 let content_mask = self.content_mask().scale(scale_factor);
2477 self.window
2478 .next_frame
2479 .scene
2480 .insert_primitive(MonochromeSprite {
2481 order: 0,
2482 pad: 0,
2483 bounds,
2484 content_mask,
2485 color,
2486 tile,
2487 transformation: TransformationMatrix::unit(),
2488 });
2489 }
2490 Ok(())
2491 }
2492
2493 /// Paints an emoji glyph into the scene for the next frame at the current z-index.
2494 ///
2495 /// The y component of the origin is the baseline of the glyph.
2496 /// You should generally prefer to use the [`ShapedLine::paint`](crate::ShapedLine::paint) or
2497 /// [`WrappedLine::paint`](crate::WrappedLine::paint) methods in the [`TextSystem`](crate::TextSystem).
2498 /// This method is only useful if you need to paint a single emoji that has already been shaped.
2499 ///
2500 /// This method should only be called as part of the paint phase of element drawing.
2501 pub fn paint_emoji(
2502 &mut self,
2503 origin: Point<Pixels>,
2504 font_id: FontId,
2505 glyph_id: GlyphId,
2506 font_size: Pixels,
2507 ) -> Result<()> {
2508 debug_assert_eq!(
2509 self.window.draw_phase,
2510 DrawPhase::Paint,
2511 "this method can only be called during paint"
2512 );
2513
2514 let scale_factor = self.scale_factor();
2515 let glyph_origin = origin.scale(scale_factor);
2516 let params = RenderGlyphParams {
2517 font_id,
2518 glyph_id,
2519 font_size,
2520 // We don't render emojis with subpixel variants.
2521 subpixel_variant: Default::default(),
2522 scale_factor,
2523 is_emoji: true,
2524 };
2525
2526 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
2527 if !raster_bounds.is_zero() {
2528 let tile = self
2529 .window
2530 .sprite_atlas
2531 .get_or_insert_with(¶ms.clone().into(), &mut || {
2532 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
2533 Ok(Some((size, Cow::Owned(bytes))))
2534 })?
2535 .expect("Callback above only errors or returns Some");
2536
2537 let bounds = Bounds {
2538 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
2539 size: tile.bounds.size.map(Into::into),
2540 };
2541 let content_mask = self.content_mask().scale(scale_factor);
2542
2543 self.window
2544 .next_frame
2545 .scene
2546 .insert_primitive(PolychromeSprite {
2547 order: 0,
2548 grayscale: false,
2549 bounds,
2550 corner_radii: Default::default(),
2551 content_mask,
2552 tile,
2553 });
2554 }
2555 Ok(())
2556 }
2557
2558 /// Paint a monochrome SVG into the scene for the next frame at the current stacking context.
2559 ///
2560 /// This method should only be called as part of the paint phase of element drawing.
2561 pub fn paint_svg(
2562 &mut self,
2563 bounds: Bounds<Pixels>,
2564 path: SharedString,
2565 transformation: TransformationMatrix,
2566 color: Hsla,
2567 ) -> Result<()> {
2568 debug_assert_eq!(
2569 self.window.draw_phase,
2570 DrawPhase::Paint,
2571 "this method can only be called during paint"
2572 );
2573
2574 let scale_factor = self.scale_factor();
2575 let bounds = bounds.scale(scale_factor);
2576 // Render the SVG at twice the size to get a higher quality result.
2577 let params = RenderSvgParams {
2578 path,
2579 size: bounds
2580 .size
2581 .map(|pixels| DevicePixels::from((pixels.0 * 2.).ceil() as i32)),
2582 };
2583
2584 let Some(tile) =
2585 self.window
2586 .sprite_atlas
2587 .get_or_insert_with(¶ms.clone().into(), &mut || {
2588 let Some(bytes) = self.svg_renderer.render(¶ms)? else {
2589 return Ok(None);
2590 };
2591 Ok(Some((params.size, Cow::Owned(bytes))))
2592 })?
2593 else {
2594 return Ok(());
2595 };
2596 let content_mask = self.content_mask().scale(scale_factor);
2597
2598 self.window
2599 .next_frame
2600 .scene
2601 .insert_primitive(MonochromeSprite {
2602 order: 0,
2603 pad: 0,
2604 bounds,
2605 content_mask,
2606 color,
2607 tile,
2608 transformation,
2609 });
2610
2611 Ok(())
2612 }
2613
2614 /// Paint an image into the scene for the next frame at the current z-index.
2615 ///
2616 /// This method should only be called as part of the paint phase of element drawing.
2617 pub fn paint_image(
2618 &mut self,
2619 bounds: Bounds<Pixels>,
2620 corner_radii: Corners<Pixels>,
2621 data: Arc<ImageData>,
2622 grayscale: bool,
2623 ) -> Result<()> {
2624 debug_assert_eq!(
2625 self.window.draw_phase,
2626 DrawPhase::Paint,
2627 "this method can only be called during paint"
2628 );
2629
2630 let scale_factor = self.scale_factor();
2631 let bounds = bounds.scale(scale_factor);
2632 let params = RenderImageParams { image_id: data.id };
2633
2634 let tile = self
2635 .window
2636 .sprite_atlas
2637 .get_or_insert_with(¶ms.clone().into(), &mut || {
2638 Ok(Some((data.size(), Cow::Borrowed(data.as_bytes()))))
2639 })?
2640 .expect("Callback above only returns Some");
2641 let content_mask = self.content_mask().scale(scale_factor);
2642 let corner_radii = corner_radii.scale(scale_factor);
2643
2644 self.window
2645 .next_frame
2646 .scene
2647 .insert_primitive(PolychromeSprite {
2648 order: 0,
2649 grayscale,
2650 bounds,
2651 content_mask,
2652 corner_radii,
2653 tile,
2654 });
2655 Ok(())
2656 }
2657
2658 /// Paint a surface into the scene for the next frame at the current z-index.
2659 ///
2660 /// This method should only be called as part of the paint phase of element drawing.
2661 #[cfg(target_os = "macos")]
2662 pub fn paint_surface(&mut self, bounds: Bounds<Pixels>, image_buffer: CVImageBuffer) {
2663 debug_assert_eq!(
2664 self.window.draw_phase,
2665 DrawPhase::Paint,
2666 "this method can only be called during paint"
2667 );
2668
2669 let scale_factor = self.scale_factor();
2670 let bounds = bounds.scale(scale_factor);
2671 let content_mask = self.content_mask().scale(scale_factor);
2672 self.window
2673 .next_frame
2674 .scene
2675 .insert_primitive(crate::Surface {
2676 order: 0,
2677 bounds,
2678 content_mask,
2679 image_buffer,
2680 });
2681 }
2682
2683 #[must_use]
2684 /// Add a node to the layout tree for the current frame. Takes the `Style` of the element for which
2685 /// layout is being requested, along with the layout ids of any children. This method is called during
2686 /// calls to the [`Element::request_layout`] trait method and enables any element to participate in layout.
2687 ///
2688 /// This method should only be called as part of the request_layout or prepaint phase of element drawing.
2689 pub fn request_layout(
2690 &mut self,
2691 style: Style,
2692 children: impl IntoIterator<Item = LayoutId>,
2693 ) -> LayoutId {
2694 debug_assert_eq!(
2695 self.window.draw_phase,
2696 DrawPhase::Prepaint,
2697 "this method can only be called during request_layout, or prepaint"
2698 );
2699
2700 self.app.layout_id_buffer.clear();
2701 self.app.layout_id_buffer.extend(children);
2702 let rem_size = self.rem_size();
2703
2704 self.window.layout_engine.as_mut().unwrap().request_layout(
2705 style,
2706 rem_size,
2707 &self.app.layout_id_buffer,
2708 )
2709 }
2710
2711 /// Add a node to the layout tree for the current frame. Instead of taking a `Style` and children,
2712 /// this variant takes a function that is invoked during layout so you can use arbitrary logic to
2713 /// determine the element's size. One place this is used internally is when measuring text.
2714 ///
2715 /// The given closure is invoked at layout time with the known dimensions and available space and
2716 /// returns a `Size`.
2717 ///
2718 /// This method should only be called as part of the request_layout or prepaint phase of element drawing.
2719 pub fn request_measured_layout<
2720 F: FnMut(Size<Option<Pixels>>, Size<AvailableSpace>, &mut WindowContext) -> Size<Pixels>
2721 + 'static,
2722 >(
2723 &mut self,
2724 style: Style,
2725 measure: F,
2726 ) -> LayoutId {
2727 debug_assert_eq!(
2728 self.window.draw_phase,
2729 DrawPhase::Prepaint,
2730 "this method can only be called during request_layout, or prepaint"
2731 );
2732
2733 let rem_size = self.rem_size();
2734 self.window
2735 .layout_engine
2736 .as_mut()
2737 .unwrap()
2738 .request_measured_layout(style, rem_size, measure)
2739 }
2740
2741 /// Compute the layout for the given id within the given available space.
2742 /// This method is called for its side effect, typically by the framework prior to painting.
2743 /// After calling it, you can request the bounds of the given layout node id or any descendant.
2744 ///
2745 /// This method should only be called as part of the prepaint phase of element drawing.
2746 pub fn compute_layout(&mut self, layout_id: LayoutId, available_space: Size<AvailableSpace>) {
2747 debug_assert_eq!(
2748 self.window.draw_phase,
2749 DrawPhase::Prepaint,
2750 "this method can only be called during request_layout, or prepaint"
2751 );
2752
2753 let mut layout_engine = self.window.layout_engine.take().unwrap();
2754 layout_engine.compute_layout(layout_id, available_space, self);
2755 self.window.layout_engine = Some(layout_engine);
2756 }
2757
2758 /// Obtain the bounds computed for the given LayoutId relative to the window. This method will usually be invoked by
2759 /// GPUI itself automatically in order to pass your element its `Bounds` automatically.
2760 ///
2761 /// This method should only be called as part of element drawing.
2762 pub fn layout_bounds(&mut self, layout_id: LayoutId) -> Bounds<Pixels> {
2763 debug_assert_eq!(
2764 self.window.draw_phase,
2765 DrawPhase::Prepaint,
2766 "this method can only be called during request_layout, prepaint, or paint"
2767 );
2768
2769 let mut bounds = self
2770 .window
2771 .layout_engine
2772 .as_mut()
2773 .unwrap()
2774 .layout_bounds(layout_id)
2775 .map(Into::into);
2776 bounds.origin += self.element_offset();
2777 bounds
2778 }
2779
2780 /// This method should be called during `prepaint`. You can use
2781 /// the returned [Hitbox] during `paint` or in an event handler
2782 /// to determine whether the inserted hitbox was the topmost.
2783 ///
2784 /// This method should only be called as part of the prepaint phase of element drawing.
2785 pub fn insert_hitbox(&mut self, bounds: Bounds<Pixels>, opaque: bool) -> Hitbox {
2786 debug_assert_eq!(
2787 self.window.draw_phase,
2788 DrawPhase::Prepaint,
2789 "this method can only be called during prepaint"
2790 );
2791
2792 let content_mask = self.content_mask();
2793 let window = &mut self.window;
2794 let id = window.next_hitbox_id;
2795 window.next_hitbox_id.0 += 1;
2796 let hitbox = Hitbox {
2797 id,
2798 bounds,
2799 content_mask,
2800 opaque,
2801 };
2802 window.next_frame.hitboxes.push(hitbox.clone());
2803 hitbox
2804 }
2805
2806 /// Sets the key context for the current element. This context will be used to translate
2807 /// keybindings into actions.
2808 ///
2809 /// This method should only be called as part of the paint phase of element drawing.
2810 pub fn set_key_context(&mut self, context: KeyContext) {
2811 debug_assert_eq!(
2812 self.window.draw_phase,
2813 DrawPhase::Paint,
2814 "this method can only be called during paint"
2815 );
2816 self.window
2817 .next_frame
2818 .dispatch_tree
2819 .set_key_context(context);
2820 }
2821
2822 /// Sets the focus handle for the current element. This handle will be used to manage focus state
2823 /// and keyboard event dispatch for the element.
2824 ///
2825 /// This method should only be called as part of the paint phase of element drawing.
2826 pub fn set_focus_handle(&mut self, focus_handle: &FocusHandle) {
2827 debug_assert_eq!(
2828 self.window.draw_phase,
2829 DrawPhase::Paint,
2830 "this method can only be called during paint"
2831 );
2832 self.window
2833 .next_frame
2834 .dispatch_tree
2835 .set_focus_id(focus_handle.id);
2836 }
2837
2838 /// Sets the view id for the current element, which will be used to manage view caching.
2839 ///
2840 /// This method should only be called as part of element prepaint. We plan on removing this
2841 /// method eventually when we solve some issues that require us to construct editor elements
2842 /// directly instead of always using editors via views.
2843 pub fn set_view_id(&mut self, view_id: EntityId) {
2844 debug_assert_eq!(
2845 self.window.draw_phase,
2846 DrawPhase::Prepaint,
2847 "this method can only be called during prepaint"
2848 );
2849 self.window.next_frame.dispatch_tree.set_view_id(view_id);
2850 }
2851
2852 /// Get the last view id for the current element
2853 pub fn parent_view_id(&mut self) -> Option<EntityId> {
2854 self.window.next_frame.dispatch_tree.parent_view_id()
2855 }
2856
2857 /// Sets an input handler, such as [`ElementInputHandler`][element_input_handler], which interfaces with the
2858 /// platform to receive textual input with proper integration with concerns such
2859 /// as IME interactions. This handler will be active for the upcoming frame until the following frame is
2860 /// rendered.
2861 ///
2862 /// This method should only be called as part of the paint phase of element drawing.
2863 ///
2864 /// [element_input_handler]: crate::ElementInputHandler
2865 pub fn handle_input(&mut self, focus_handle: &FocusHandle, input_handler: impl InputHandler) {
2866 debug_assert_eq!(
2867 self.window.draw_phase,
2868 DrawPhase::Paint,
2869 "this method can only be called during paint"
2870 );
2871
2872 if focus_handle.is_focused(self) {
2873 let cx = self.to_async();
2874 self.window
2875 .next_frame
2876 .input_handlers
2877 .push(Some(PlatformInputHandler::new(cx, Box::new(input_handler))));
2878 }
2879 }
2880
2881 /// Register a mouse event listener on the window for the next frame. The type of event
2882 /// is determined by the first parameter of the given listener. When the next frame is rendered
2883 /// the listener will be cleared.
2884 ///
2885 /// This method should only be called as part of the paint phase of element drawing.
2886 pub fn on_mouse_event<Event: MouseEvent>(
2887 &mut self,
2888 mut handler: impl FnMut(&Event, DispatchPhase, &mut WindowContext) + 'static,
2889 ) {
2890 debug_assert_eq!(
2891 self.window.draw_phase,
2892 DrawPhase::Paint,
2893 "this method can only be called during paint"
2894 );
2895
2896 self.window.next_frame.mouse_listeners.push(Some(Box::new(
2897 move |event: &dyn Any, phase: DispatchPhase, cx: &mut WindowContext<'_>| {
2898 if let Some(event) = event.downcast_ref() {
2899 handler(event, phase, cx)
2900 }
2901 },
2902 )));
2903 }
2904
2905 /// Register a key event listener on the window for the next frame. The type of event
2906 /// is determined by the first parameter of the given listener. When the next frame is rendered
2907 /// the listener will be cleared.
2908 ///
2909 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
2910 /// a specific need to register a global listener.
2911 ///
2912 /// This method should only be called as part of the paint phase of element drawing.
2913 pub fn on_key_event<Event: KeyEvent>(
2914 &mut self,
2915 listener: impl Fn(&Event, DispatchPhase, &mut WindowContext) + 'static,
2916 ) {
2917 debug_assert_eq!(
2918 self.window.draw_phase,
2919 DrawPhase::Paint,
2920 "this method can only be called during paint"
2921 );
2922
2923 self.window.next_frame.dispatch_tree.on_key_event(Rc::new(
2924 move |event: &dyn Any, phase, cx: &mut WindowContext<'_>| {
2925 if let Some(event) = event.downcast_ref::<Event>() {
2926 listener(event, phase, cx)
2927 }
2928 },
2929 ));
2930 }
2931
2932 /// Register a modifiers changed event listener on the window for the next frame.
2933 ///
2934 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
2935 /// a specific need to register a global listener.
2936 ///
2937 /// This method should only be called as part of the paint phase of element drawing.
2938 pub fn on_modifiers_changed(
2939 &mut self,
2940 listener: impl Fn(&ModifiersChangedEvent, &mut WindowContext) + 'static,
2941 ) {
2942 debug_assert_eq!(
2943 self.window.draw_phase,
2944 DrawPhase::Paint,
2945 "this method can only be called during paint"
2946 );
2947
2948 self.window
2949 .next_frame
2950 .dispatch_tree
2951 .on_modifiers_changed(Rc::new(
2952 move |event: &ModifiersChangedEvent, cx: &mut WindowContext<'_>| {
2953 listener(event, cx)
2954 },
2955 ));
2956 }
2957
2958 /// Register a listener to be called when the given focus handle or one of its descendants receives focus.
2959 /// This does not fire if the given focus handle - or one of its descendants - was previously focused.
2960 /// Returns a subscription and persists until the subscription is dropped.
2961 pub fn on_focus_in(
2962 &mut self,
2963 handle: &FocusHandle,
2964 mut listener: impl FnMut(&mut WindowContext) + 'static,
2965 ) -> Subscription {
2966 let focus_id = handle.id;
2967 let (subscription, activate) =
2968 self.window.new_focus_listener(Box::new(move |event, cx| {
2969 if event.is_focus_in(focus_id) {
2970 listener(cx);
2971 }
2972 true
2973 }));
2974 self.app.defer(move |_| activate());
2975 subscription
2976 }
2977
2978 /// Register a listener to be called when the given focus handle or one of its descendants loses focus.
2979 /// Returns a subscription and persists until the subscription is dropped.
2980 pub fn on_focus_out(
2981 &mut self,
2982 handle: &FocusHandle,
2983 mut listener: impl FnMut(FocusOutEvent, &mut WindowContext) + 'static,
2984 ) -> Subscription {
2985 let focus_id = handle.id;
2986 let (subscription, activate) =
2987 self.window.new_focus_listener(Box::new(move |event, cx| {
2988 if let Some(blurred_id) = event.previous_focus_path.last().copied() {
2989 if event.is_focus_out(focus_id) {
2990 let event = FocusOutEvent {
2991 blurred: WeakFocusHandle {
2992 id: blurred_id,
2993 handles: Arc::downgrade(&cx.window.focus_handles),
2994 },
2995 };
2996 listener(event, cx)
2997 }
2998 }
2999 true
3000 }));
3001 self.app.defer(move |_| activate());
3002 subscription
3003 }
3004
3005 fn reset_cursor_style(&self) {
3006 // Set the cursor only if we're the active window.
3007 if self.is_window_hovered() {
3008 let style = self
3009 .window
3010 .rendered_frame
3011 .cursor_styles
3012 .iter()
3013 .rev()
3014 .find(|request| request.hitbox_id.is_hovered(self))
3015 .map(|request| request.style)
3016 .unwrap_or(CursorStyle::Arrow);
3017 self.platform.set_cursor_style(style);
3018 }
3019 }
3020
3021 /// Dispatch a given keystroke as though the user had typed it.
3022 /// You can create a keystroke with Keystroke::parse("").
3023 pub fn dispatch_keystroke(&mut self, keystroke: Keystroke) -> bool {
3024 let keystroke = keystroke.with_simulated_ime();
3025 let result = self.dispatch_event(PlatformInput::KeyDown(KeyDownEvent {
3026 keystroke: keystroke.clone(),
3027 is_held: false,
3028 }));
3029 if !result.propagate {
3030 return true;
3031 }
3032
3033 if let Some(input) = keystroke.ime_key {
3034 if let Some(mut input_handler) = self.window.platform_window.take_input_handler() {
3035 input_handler.dispatch_input(&input, self);
3036 self.window.platform_window.set_input_handler(input_handler);
3037 return true;
3038 }
3039 }
3040
3041 false
3042 }
3043
3044 /// Represent this action as a key binding string, to display in the UI.
3045 pub fn keystroke_text_for(&self, action: &dyn Action) -> String {
3046 self.bindings_for_action(action)
3047 .into_iter()
3048 .next()
3049 .map(|binding| {
3050 binding
3051 .keystrokes()
3052 .iter()
3053 .map(ToString::to_string)
3054 .collect::<Vec<_>>()
3055 .join(" ")
3056 })
3057 .unwrap_or_else(|| action.name().to_string())
3058 }
3059
3060 /// Dispatch a mouse or keyboard event on the window.
3061 #[profiling::function]
3062 pub fn dispatch_event(&mut self, event: PlatformInput) -> DispatchEventResult {
3063 self.window.last_input_timestamp.set(Instant::now());
3064 // Handlers may set this to false by calling `stop_propagation`.
3065 self.app.propagate_event = true;
3066 // Handlers may set this to true by calling `prevent_default`.
3067 self.window.default_prevented = false;
3068
3069 let event = match event {
3070 // Track the mouse position with our own state, since accessing the platform
3071 // API for the mouse position can only occur on the main thread.
3072 PlatformInput::MouseMove(mouse_move) => {
3073 self.window.mouse_position = mouse_move.position;
3074 self.window.modifiers = mouse_move.modifiers;
3075 PlatformInput::MouseMove(mouse_move)
3076 }
3077 PlatformInput::MouseDown(mouse_down) => {
3078 self.window.mouse_position = mouse_down.position;
3079 self.window.modifiers = mouse_down.modifiers;
3080 PlatformInput::MouseDown(mouse_down)
3081 }
3082 PlatformInput::MouseUp(mouse_up) => {
3083 self.window.mouse_position = mouse_up.position;
3084 self.window.modifiers = mouse_up.modifiers;
3085 PlatformInput::MouseUp(mouse_up)
3086 }
3087 PlatformInput::MouseExited(mouse_exited) => {
3088 self.window.modifiers = mouse_exited.modifiers;
3089 PlatformInput::MouseExited(mouse_exited)
3090 }
3091 PlatformInput::ModifiersChanged(modifiers_changed) => {
3092 self.window.modifiers = modifiers_changed.modifiers;
3093 PlatformInput::ModifiersChanged(modifiers_changed)
3094 }
3095 PlatformInput::ScrollWheel(scroll_wheel) => {
3096 self.window.mouse_position = scroll_wheel.position;
3097 self.window.modifiers = scroll_wheel.modifiers;
3098 PlatformInput::ScrollWheel(scroll_wheel)
3099 }
3100 // Translate dragging and dropping of external files from the operating system
3101 // to internal drag and drop events.
3102 PlatformInput::FileDrop(file_drop) => match file_drop {
3103 FileDropEvent::Entered { position, paths } => {
3104 self.window.mouse_position = position;
3105 if self.active_drag.is_none() {
3106 self.active_drag = Some(AnyDrag {
3107 value: Box::new(paths.clone()),
3108 view: self.new_view(|_| paths).into(),
3109 cursor_offset: position,
3110 });
3111 }
3112 PlatformInput::MouseMove(MouseMoveEvent {
3113 position,
3114 pressed_button: Some(MouseButton::Left),
3115 modifiers: Modifiers::default(),
3116 })
3117 }
3118 FileDropEvent::Pending { position } => {
3119 self.window.mouse_position = position;
3120 PlatformInput::MouseMove(MouseMoveEvent {
3121 position,
3122 pressed_button: Some(MouseButton::Left),
3123 modifiers: Modifiers::default(),
3124 })
3125 }
3126 FileDropEvent::Submit { position } => {
3127 self.activate(true);
3128 self.window.mouse_position = position;
3129 PlatformInput::MouseUp(MouseUpEvent {
3130 button: MouseButton::Left,
3131 position,
3132 modifiers: Modifiers::default(),
3133 click_count: 1,
3134 })
3135 }
3136 FileDropEvent::Exited => {
3137 self.active_drag.take();
3138 PlatformInput::FileDrop(FileDropEvent::Exited)
3139 }
3140 },
3141 PlatformInput::KeyDown(_) | PlatformInput::KeyUp(_) => event,
3142 };
3143
3144 if let Some(any_mouse_event) = event.mouse_event() {
3145 self.dispatch_mouse_event(any_mouse_event);
3146 } else if let Some(any_key_event) = event.keyboard_event() {
3147 self.dispatch_key_event(any_key_event);
3148 }
3149
3150 DispatchEventResult {
3151 propagate: self.app.propagate_event,
3152 default_prevented: self.window.default_prevented,
3153 }
3154 }
3155
3156 fn dispatch_mouse_event(&mut self, event: &dyn Any) {
3157 let hit_test = self.window.rendered_frame.hit_test(self.mouse_position());
3158 if hit_test != self.window.mouse_hit_test {
3159 self.window.mouse_hit_test = hit_test;
3160 self.reset_cursor_style();
3161 }
3162
3163 let mut mouse_listeners = mem::take(&mut self.window.rendered_frame.mouse_listeners);
3164
3165 // Capture phase, events bubble from back to front. Handlers for this phase are used for
3166 // special purposes, such as detecting events outside of a given Bounds.
3167 for listener in &mut mouse_listeners {
3168 let listener = listener.as_mut().unwrap();
3169 listener(event, DispatchPhase::Capture, self);
3170 if !self.app.propagate_event {
3171 break;
3172 }
3173 }
3174
3175 // Bubble phase, where most normal handlers do their work.
3176 if self.app.propagate_event {
3177 for listener in mouse_listeners.iter_mut().rev() {
3178 let listener = listener.as_mut().unwrap();
3179 listener(event, DispatchPhase::Bubble, self);
3180 if !self.app.propagate_event {
3181 break;
3182 }
3183 }
3184 }
3185
3186 self.window.rendered_frame.mouse_listeners = mouse_listeners;
3187
3188 if self.has_active_drag() {
3189 if event.is::<MouseMoveEvent>() {
3190 // If this was a mouse move event, redraw the window so that the
3191 // active drag can follow the mouse cursor.
3192 self.refresh();
3193 } else if event.is::<MouseUpEvent>() {
3194 // If this was a mouse up event, cancel the active drag and redraw
3195 // the window.
3196 self.active_drag = None;
3197 self.refresh();
3198 }
3199 }
3200 }
3201
3202 fn dispatch_key_event(&mut self, event: &dyn Any) {
3203 if self.window.dirty.get() {
3204 self.draw();
3205 }
3206
3207 let node_id = self
3208 .window
3209 .focus
3210 .and_then(|focus_id| {
3211 self.window
3212 .rendered_frame
3213 .dispatch_tree
3214 .focusable_node_id(focus_id)
3215 })
3216 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3217
3218 let dispatch_path = self
3219 .window
3220 .rendered_frame
3221 .dispatch_tree
3222 .dispatch_path(node_id);
3223
3224 let mut bindings: SmallVec<[KeyBinding; 1]> = SmallVec::new();
3225 let mut pending = false;
3226 let mut keystroke: Option<Keystroke> = None;
3227
3228 if let Some(event) = event.downcast_ref::<ModifiersChangedEvent>() {
3229 if event.modifiers.number_of_modifiers() == 0
3230 && self.window.pending_modifier.modifiers.number_of_modifiers() == 1
3231 && !self.window.pending_modifier.saw_keystroke
3232 {
3233 if event.modifiers.number_of_modifiers() == 0 {
3234 let key = match self.window.pending_modifier.modifiers {
3235 modifiers if modifiers.shift => Some("shift"),
3236 modifiers if modifiers.control => Some("control"),
3237 modifiers if modifiers.alt => Some("alt"),
3238 modifiers if modifiers.platform => Some("platform"),
3239 modifiers if modifiers.function => Some("function"),
3240 _ => None,
3241 };
3242 if let Some(key) = key {
3243 let key = Keystroke {
3244 key: key.to_string(),
3245 ime_key: None,
3246 modifiers: Modifiers::default(),
3247 };
3248 let KeymatchResult {
3249 bindings: modifier_bindings,
3250 pending: pending_bindings,
3251 } = self
3252 .window
3253 .rendered_frame
3254 .dispatch_tree
3255 .dispatch_key(&key, &dispatch_path);
3256
3257 keystroke = Some(key);
3258 bindings = modifier_bindings;
3259 pending = pending_bindings;
3260 }
3261 }
3262 }
3263 if self.window.pending_modifier.modifiers.number_of_modifiers() == 0
3264 && event.modifiers.number_of_modifiers() == 1
3265 {
3266 self.window.pending_modifier.saw_keystroke = false
3267 }
3268 self.window.pending_modifier.modifiers = event.modifiers
3269 } else if let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() {
3270 self.window.pending_modifier.saw_keystroke = true;
3271 let KeymatchResult {
3272 bindings: key_down_bindings,
3273 pending: key_down_pending,
3274 } = self
3275 .window
3276 .rendered_frame
3277 .dispatch_tree
3278 .dispatch_key(&key_down_event.keystroke, &dispatch_path);
3279
3280 keystroke = Some(key_down_event.keystroke.clone());
3281
3282 bindings = key_down_bindings;
3283 pending = key_down_pending;
3284 }
3285
3286 if keystroke.is_none() {
3287 self.finish_dispatch_key_event(event, dispatch_path);
3288 return;
3289 }
3290
3291 if pending {
3292 let mut currently_pending = self.window.pending_input.take().unwrap_or_default();
3293 if currently_pending.focus.is_some() && currently_pending.focus != self.window.focus {
3294 currently_pending = PendingInput::default();
3295 }
3296 currently_pending.focus = self.window.focus;
3297 if let Some(keystroke) = keystroke {
3298 currently_pending.keystrokes.push(keystroke.clone());
3299 }
3300 for binding in bindings {
3301 currently_pending.bindings.push(binding);
3302 }
3303
3304 currently_pending.timer = Some(self.spawn(|mut cx| async move {
3305 cx.background_executor.timer(Duration::from_secs(1)).await;
3306 cx.update(move |cx| {
3307 cx.clear_pending_keystrokes();
3308 let Some(currently_pending) = cx.window.pending_input.take() else {
3309 return;
3310 };
3311 cx.replay_pending_input(currently_pending);
3312 cx.pending_input_changed();
3313 })
3314 .log_err();
3315 }));
3316
3317 self.window.pending_input = Some(currently_pending);
3318 self.pending_input_changed();
3319
3320 self.propagate_event = false;
3321 return;
3322 } else if let Some(currently_pending) = self.window.pending_input.take() {
3323 self.pending_input_changed();
3324 if bindings
3325 .iter()
3326 .all(|binding| !currently_pending.used_by_binding(binding))
3327 {
3328 self.replay_pending_input(currently_pending)
3329 }
3330 }
3331
3332 if !bindings.is_empty() {
3333 self.clear_pending_keystrokes();
3334 }
3335
3336 self.propagate_event = true;
3337 for binding in bindings {
3338 self.dispatch_action_on_node(node_id, binding.action.as_ref());
3339 if !self.propagate_event {
3340 self.dispatch_keystroke_observers(event, Some(binding.action));
3341 return;
3342 }
3343 }
3344
3345 self.finish_dispatch_key_event(event, dispatch_path)
3346 }
3347
3348 fn finish_dispatch_key_event(
3349 &mut self,
3350 event: &dyn Any,
3351 dispatch_path: SmallVec<[DispatchNodeId; 32]>,
3352 ) {
3353 self.dispatch_key_down_up_event(event, &dispatch_path);
3354 if !self.propagate_event {
3355 return;
3356 }
3357
3358 self.dispatch_modifiers_changed_event(event, &dispatch_path);
3359 if !self.propagate_event {
3360 return;
3361 }
3362
3363 self.dispatch_keystroke_observers(event, None);
3364 }
3365
3366 fn pending_input_changed(&mut self) {
3367 self.window
3368 .pending_input_observers
3369 .clone()
3370 .retain(&(), |callback| callback(self));
3371 }
3372
3373 fn dispatch_key_down_up_event(
3374 &mut self,
3375 event: &dyn Any,
3376 dispatch_path: &SmallVec<[DispatchNodeId; 32]>,
3377 ) {
3378 // Capture phase
3379 for node_id in dispatch_path {
3380 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3381
3382 for key_listener in node.key_listeners.clone() {
3383 key_listener(event, DispatchPhase::Capture, self);
3384 if !self.propagate_event {
3385 return;
3386 }
3387 }
3388 }
3389
3390 // Bubble phase
3391 for node_id in dispatch_path.iter().rev() {
3392 // Handle low level key events
3393 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3394 for key_listener in node.key_listeners.clone() {
3395 key_listener(event, DispatchPhase::Bubble, self);
3396 if !self.propagate_event {
3397 return;
3398 }
3399 }
3400 }
3401 }
3402
3403 fn dispatch_modifiers_changed_event(
3404 &mut self,
3405 event: &dyn Any,
3406 dispatch_path: &SmallVec<[DispatchNodeId; 32]>,
3407 ) {
3408 let Some(event) = event.downcast_ref::<ModifiersChangedEvent>() else {
3409 return;
3410 };
3411 for node_id in dispatch_path.iter().rev() {
3412 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3413 for listener in node.modifiers_changed_listeners.clone() {
3414 listener(event, self);
3415 if !self.propagate_event {
3416 return;
3417 }
3418 }
3419 }
3420 }
3421
3422 /// Determine whether a potential multi-stroke key binding is in progress on this window.
3423 pub fn has_pending_keystrokes(&self) -> bool {
3424 self.window
3425 .rendered_frame
3426 .dispatch_tree
3427 .has_pending_keystrokes()
3428 }
3429
3430 /// Returns the currently pending input keystrokes that might result in a multi-stroke key binding.
3431 pub fn pending_input_keystrokes(&self) -> Option<&[Keystroke]> {
3432 self.window
3433 .pending_input
3434 .as_ref()
3435 .map(|pending_input| pending_input.keystrokes.as_slice())
3436 }
3437
3438 fn replay_pending_input(&mut self, currently_pending: PendingInput) {
3439 let node_id = self
3440 .window
3441 .focus
3442 .and_then(|focus_id| {
3443 self.window
3444 .rendered_frame
3445 .dispatch_tree
3446 .focusable_node_id(focus_id)
3447 })
3448 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3449
3450 if self.window.focus != currently_pending.focus {
3451 return;
3452 }
3453
3454 let input = currently_pending.input();
3455
3456 self.propagate_event = true;
3457 for binding in currently_pending.bindings {
3458 self.dispatch_action_on_node(node_id, binding.action.as_ref());
3459 if !self.propagate_event {
3460 return;
3461 }
3462 }
3463
3464 let dispatch_path = self
3465 .window
3466 .rendered_frame
3467 .dispatch_tree
3468 .dispatch_path(node_id);
3469
3470 for keystroke in currently_pending.keystrokes {
3471 let event = KeyDownEvent {
3472 keystroke,
3473 is_held: false,
3474 };
3475
3476 self.dispatch_key_down_up_event(&event, &dispatch_path);
3477 if !self.propagate_event {
3478 return;
3479 }
3480 }
3481
3482 if !input.is_empty() {
3483 if let Some(mut input_handler) = self.window.platform_window.take_input_handler() {
3484 input_handler.dispatch_input(&input, self);
3485 self.window.platform_window.set_input_handler(input_handler)
3486 }
3487 }
3488 }
3489
3490 fn dispatch_action_on_node(&mut self, node_id: DispatchNodeId, action: &dyn Action) {
3491 let dispatch_path = self
3492 .window
3493 .rendered_frame
3494 .dispatch_tree
3495 .dispatch_path(node_id);
3496
3497 // Capture phase for global actions.
3498 self.propagate_event = true;
3499 if let Some(mut global_listeners) = self
3500 .global_action_listeners
3501 .remove(&action.as_any().type_id())
3502 {
3503 for listener in &global_listeners {
3504 listener(action.as_any(), DispatchPhase::Capture, self);
3505 if !self.propagate_event {
3506 break;
3507 }
3508 }
3509
3510 global_listeners.extend(
3511 self.global_action_listeners
3512 .remove(&action.as_any().type_id())
3513 .unwrap_or_default(),
3514 );
3515
3516 self.global_action_listeners
3517 .insert(action.as_any().type_id(), global_listeners);
3518 }
3519
3520 if !self.propagate_event {
3521 return;
3522 }
3523
3524 // Capture phase for window actions.
3525 for node_id in &dispatch_path {
3526 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3527 for DispatchActionListener {
3528 action_type,
3529 listener,
3530 } in node.action_listeners.clone()
3531 {
3532 let any_action = action.as_any();
3533 if action_type == any_action.type_id() {
3534 listener(any_action, DispatchPhase::Capture, self);
3535
3536 if !self.propagate_event {
3537 return;
3538 }
3539 }
3540 }
3541 }
3542
3543 // Bubble phase for window actions.
3544 for node_id in dispatch_path.iter().rev() {
3545 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3546 for DispatchActionListener {
3547 action_type,
3548 listener,
3549 } in node.action_listeners.clone()
3550 {
3551 let any_action = action.as_any();
3552 if action_type == any_action.type_id() {
3553 self.propagate_event = false; // Actions stop propagation by default during the bubble phase
3554 listener(any_action, DispatchPhase::Bubble, self);
3555
3556 if !self.propagate_event {
3557 return;
3558 }
3559 }
3560 }
3561 }
3562
3563 // Bubble phase for global actions.
3564 if let Some(mut global_listeners) = self
3565 .global_action_listeners
3566 .remove(&action.as_any().type_id())
3567 {
3568 for listener in global_listeners.iter().rev() {
3569 self.propagate_event = false; // Actions stop propagation by default during the bubble phase
3570
3571 listener(action.as_any(), DispatchPhase::Bubble, self);
3572 if !self.propagate_event {
3573 break;
3574 }
3575 }
3576
3577 global_listeners.extend(
3578 self.global_action_listeners
3579 .remove(&action.as_any().type_id())
3580 .unwrap_or_default(),
3581 );
3582
3583 self.global_action_listeners
3584 .insert(action.as_any().type_id(), global_listeners);
3585 }
3586 }
3587
3588 /// Register the given handler to be invoked whenever the global of the given type
3589 /// is updated.
3590 pub fn observe_global<G: Global>(
3591 &mut self,
3592 f: impl Fn(&mut WindowContext<'_>) + 'static,
3593 ) -> Subscription {
3594 let window_handle = self.window.handle;
3595 let (subscription, activate) = self.global_observers.insert(
3596 TypeId::of::<G>(),
3597 Box::new(move |cx| window_handle.update(cx, |_, cx| f(cx)).is_ok()),
3598 );
3599 self.app.defer(move |_| activate());
3600 subscription
3601 }
3602
3603 /// Focus the current window and bring it to the foreground at the platform level.
3604 pub fn activate_window(&self) {
3605 self.window.platform_window.activate();
3606 }
3607
3608 /// Minimize the current window at the platform level.
3609 pub fn minimize_window(&self) {
3610 self.window.platform_window.minimize();
3611 }
3612
3613 /// Toggle full screen status on the current window at the platform level.
3614 pub fn toggle_fullscreen(&self) {
3615 self.window.platform_window.toggle_fullscreen();
3616 }
3617
3618 /// Present a platform dialog.
3619 /// The provided message will be presented, along with buttons for each answer.
3620 /// When a button is clicked, the returned Receiver will receive the index of the clicked button.
3621 pub fn prompt(
3622 &mut self,
3623 level: PromptLevel,
3624 message: &str,
3625 detail: Option<&str>,
3626 answers: &[&str],
3627 ) -> oneshot::Receiver<usize> {
3628 let prompt_builder = self.app.prompt_builder.take();
3629 let Some(prompt_builder) = prompt_builder else {
3630 unreachable!("Re-entrant window prompting is not supported by GPUI");
3631 };
3632
3633 let receiver = match &prompt_builder {
3634 PromptBuilder::Default => self
3635 .window
3636 .platform_window
3637 .prompt(level, message, detail, answers)
3638 .unwrap_or_else(|| {
3639 self.build_custom_prompt(&prompt_builder, level, message, detail, answers)
3640 }),
3641 PromptBuilder::Custom(_) => {
3642 self.build_custom_prompt(&prompt_builder, level, message, detail, answers)
3643 }
3644 };
3645
3646 self.app.prompt_builder = Some(prompt_builder);
3647
3648 receiver
3649 }
3650
3651 fn build_custom_prompt(
3652 &mut self,
3653 prompt_builder: &PromptBuilder,
3654 level: PromptLevel,
3655 message: &str,
3656 detail: Option<&str>,
3657 answers: &[&str],
3658 ) -> oneshot::Receiver<usize> {
3659 let (sender, receiver) = oneshot::channel();
3660 let handle = PromptHandle::new(sender);
3661 let handle = (prompt_builder)(level, message, detail, answers, handle, self);
3662 self.window.prompt = Some(handle);
3663 receiver
3664 }
3665
3666 /// Returns all available actions for the focused element.
3667 pub fn available_actions(&self) -> Vec<Box<dyn Action>> {
3668 let node_id = self
3669 .window
3670 .focus
3671 .and_then(|focus_id| {
3672 self.window
3673 .rendered_frame
3674 .dispatch_tree
3675 .focusable_node_id(focus_id)
3676 })
3677 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3678
3679 let mut actions = self
3680 .window
3681 .rendered_frame
3682 .dispatch_tree
3683 .available_actions(node_id);
3684 for action_type in self.global_action_listeners.keys() {
3685 if let Err(ix) = actions.binary_search_by_key(action_type, |a| a.as_any().type_id()) {
3686 let action = self.actions.build_action_type(action_type).ok();
3687 if let Some(action) = action {
3688 actions.insert(ix, action);
3689 }
3690 }
3691 }
3692 actions
3693 }
3694
3695 /// Returns key bindings that invoke the given action on the currently focused element.
3696 pub fn bindings_for_action(&self, action: &dyn Action) -> Vec<KeyBinding> {
3697 self.window
3698 .rendered_frame
3699 .dispatch_tree
3700 .bindings_for_action(
3701 action,
3702 &self.window.rendered_frame.dispatch_tree.context_stack,
3703 )
3704 }
3705
3706 /// Returns any bindings that would invoke the given action on the given focus handle if it were focused.
3707 pub fn bindings_for_action_in(
3708 &self,
3709 action: &dyn Action,
3710 focus_handle: &FocusHandle,
3711 ) -> Vec<KeyBinding> {
3712 let dispatch_tree = &self.window.rendered_frame.dispatch_tree;
3713
3714 let Some(node_id) = dispatch_tree.focusable_node_id(focus_handle.id) else {
3715 return vec![];
3716 };
3717 let context_stack: Vec<_> = dispatch_tree
3718 .dispatch_path(node_id)
3719 .into_iter()
3720 .filter_map(|node_id| dispatch_tree.node(node_id).context.clone())
3721 .collect();
3722 dispatch_tree.bindings_for_action(action, &context_stack)
3723 }
3724
3725 /// Returns a generic event listener that invokes the given listener with the view and context associated with the given view handle.
3726 pub fn listener_for<V: Render, E>(
3727 &self,
3728 view: &View<V>,
3729 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
3730 ) -> impl Fn(&E, &mut WindowContext) + 'static {
3731 let view = view.downgrade();
3732 move |e: &E, cx: &mut WindowContext| {
3733 view.update(cx, |view, cx| f(view, e, cx)).ok();
3734 }
3735 }
3736
3737 /// Returns a generic handler that invokes the given handler with the view and context associated with the given view handle.
3738 pub fn handler_for<V: Render>(
3739 &self,
3740 view: &View<V>,
3741 f: impl Fn(&mut V, &mut ViewContext<V>) + 'static,
3742 ) -> impl Fn(&mut WindowContext) {
3743 let view = view.downgrade();
3744 move |cx: &mut WindowContext| {
3745 view.update(cx, |view, cx| f(view, cx)).ok();
3746 }
3747 }
3748
3749 /// Register a callback that can interrupt the closing of the current window based the returned boolean.
3750 /// If the callback returns false, the window won't be closed.
3751 pub fn on_window_should_close(&mut self, f: impl Fn(&mut WindowContext) -> bool + 'static) {
3752 let mut this = self.to_async();
3753 self.window
3754 .platform_window
3755 .on_should_close(Box::new(move || this.update(|cx| f(cx)).unwrap_or(true)))
3756 }
3757
3758 /// Register an action listener on the window for the next frame. The type of action
3759 /// is determined by the first parameter of the given listener. When the next frame is rendered
3760 /// the listener will be cleared.
3761 ///
3762 /// This is a fairly low-level method, so prefer using action handlers on elements unless you have
3763 /// a specific need to register a global listener.
3764 pub fn on_action(
3765 &mut self,
3766 action_type: TypeId,
3767 listener: impl Fn(&dyn Any, DispatchPhase, &mut WindowContext) + 'static,
3768 ) {
3769 self.window
3770 .next_frame
3771 .dispatch_tree
3772 .on_action(action_type, Rc::new(listener));
3773 }
3774}
3775
3776#[cfg(target_os = "windows")]
3777impl WindowContext<'_> {
3778 /// Returns the raw HWND handle for the window.
3779 pub fn get_raw_handle(&self) -> windows::Win32::Foundation::HWND {
3780 self.window.platform_window.get_raw_handle()
3781 }
3782}
3783
3784impl Context for WindowContext<'_> {
3785 type Result<T> = T;
3786
3787 fn new_model<T>(&mut self, build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T) -> Model<T>
3788 where
3789 T: 'static,
3790 {
3791 let slot = self.app.entities.reserve();
3792 let model = build_model(&mut ModelContext::new(&mut *self.app, slot.downgrade()));
3793 self.entities.insert(slot, model)
3794 }
3795
3796 fn reserve_model<T: 'static>(&mut self) -> Self::Result<crate::Reservation<T>> {
3797 self.app.reserve_model()
3798 }
3799
3800 fn insert_model<T: 'static>(
3801 &mut self,
3802 reservation: crate::Reservation<T>,
3803 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
3804 ) -> Self::Result<Model<T>> {
3805 self.app.insert_model(reservation, build_model)
3806 }
3807
3808 fn update_model<T: 'static, R>(
3809 &mut self,
3810 model: &Model<T>,
3811 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
3812 ) -> R {
3813 let mut entity = self.entities.lease(model);
3814 let result = update(
3815 &mut *entity,
3816 &mut ModelContext::new(&mut *self.app, model.downgrade()),
3817 );
3818 self.entities.end_lease(entity);
3819 result
3820 }
3821
3822 fn read_model<T, R>(
3823 &self,
3824 handle: &Model<T>,
3825 read: impl FnOnce(&T, &AppContext) -> R,
3826 ) -> Self::Result<R>
3827 where
3828 T: 'static,
3829 {
3830 let entity = self.entities.read(handle);
3831 read(entity, &*self.app)
3832 }
3833
3834 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
3835 where
3836 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
3837 {
3838 if window == self.window.handle {
3839 let root_view = self.window.root_view.clone().unwrap();
3840 Ok(update(root_view, self))
3841 } else {
3842 window.update(self.app, update)
3843 }
3844 }
3845
3846 fn read_window<T, R>(
3847 &self,
3848 window: &WindowHandle<T>,
3849 read: impl FnOnce(View<T>, &AppContext) -> R,
3850 ) -> Result<R>
3851 where
3852 T: 'static,
3853 {
3854 if window.any_handle == self.window.handle {
3855 let root_view = self
3856 .window
3857 .root_view
3858 .clone()
3859 .unwrap()
3860 .downcast::<T>()
3861 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
3862 Ok(read(root_view, self))
3863 } else {
3864 self.app.read_window(window, read)
3865 }
3866 }
3867}
3868
3869impl VisualContext for WindowContext<'_> {
3870 fn new_view<V>(
3871 &mut self,
3872 build_view_state: impl FnOnce(&mut ViewContext<'_, V>) -> V,
3873 ) -> Self::Result<View<V>>
3874 where
3875 V: 'static + Render,
3876 {
3877 let slot = self.app.entities.reserve();
3878 let view = View {
3879 model: slot.clone(),
3880 };
3881 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
3882 let entity = build_view_state(&mut cx);
3883 cx.entities.insert(slot, entity);
3884
3885 // Non-generic part to avoid leaking SubscriberSet to invokers of `new_view`.
3886 fn notify_observers(cx: &mut WindowContext, tid: TypeId, view: AnyView) {
3887 cx.new_view_observers.clone().retain(&tid, |observer| {
3888 let any_view = view.clone();
3889 (observer)(any_view, cx);
3890 true
3891 });
3892 }
3893 notify_observers(self, TypeId::of::<V>(), AnyView::from(view.clone()));
3894
3895 view
3896 }
3897
3898 /// Updates the given view. Prefer calling [`View::update`] instead, which calls this method.
3899 fn update_view<T: 'static, R>(
3900 &mut self,
3901 view: &View<T>,
3902 update: impl FnOnce(&mut T, &mut ViewContext<'_, T>) -> R,
3903 ) -> Self::Result<R> {
3904 let mut lease = self.app.entities.lease(&view.model);
3905 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, view);
3906 let result = update(&mut *lease, &mut cx);
3907 cx.app.entities.end_lease(lease);
3908 result
3909 }
3910
3911 fn replace_root_view<V>(
3912 &mut self,
3913 build_view: impl FnOnce(&mut ViewContext<'_, V>) -> V,
3914 ) -> Self::Result<View<V>>
3915 where
3916 V: 'static + Render,
3917 {
3918 let view = self.new_view(build_view);
3919 self.window.root_view = Some(view.clone().into());
3920 self.refresh();
3921 view
3922 }
3923
3924 fn focus_view<V: crate::FocusableView>(&mut self, view: &View<V>) -> Self::Result<()> {
3925 self.update_view(view, |view, cx| {
3926 view.focus_handle(cx).clone().focus(cx);
3927 })
3928 }
3929
3930 fn dismiss_view<V>(&mut self, view: &View<V>) -> Self::Result<()>
3931 where
3932 V: ManagedView,
3933 {
3934 self.update_view(view, |_, cx| cx.emit(DismissEvent))
3935 }
3936}
3937
3938impl<'a> std::ops::Deref for WindowContext<'a> {
3939 type Target = AppContext;
3940
3941 fn deref(&self) -> &Self::Target {
3942 self.app
3943 }
3944}
3945
3946impl<'a> std::ops::DerefMut for WindowContext<'a> {
3947 fn deref_mut(&mut self) -> &mut Self::Target {
3948 self.app
3949 }
3950}
3951
3952impl<'a> Borrow<AppContext> for WindowContext<'a> {
3953 fn borrow(&self) -> &AppContext {
3954 self.app
3955 }
3956}
3957
3958impl<'a> BorrowMut<AppContext> for WindowContext<'a> {
3959 fn borrow_mut(&mut self) -> &mut AppContext {
3960 self.app
3961 }
3962}
3963
3964/// This trait contains functionality that is shared across [`ViewContext`] and [`WindowContext`]
3965pub trait BorrowWindow: BorrowMut<Window> + BorrowMut<AppContext> {
3966 #[doc(hidden)]
3967 fn app_mut(&mut self) -> &mut AppContext {
3968 self.borrow_mut()
3969 }
3970
3971 #[doc(hidden)]
3972 fn app(&self) -> &AppContext {
3973 self.borrow()
3974 }
3975
3976 #[doc(hidden)]
3977 fn window(&self) -> &Window {
3978 self.borrow()
3979 }
3980
3981 #[doc(hidden)]
3982 fn window_mut(&mut self) -> &mut Window {
3983 self.borrow_mut()
3984 }
3985}
3986
3987impl Borrow<Window> for WindowContext<'_> {
3988 fn borrow(&self) -> &Window {
3989 self.window
3990 }
3991}
3992
3993impl BorrowMut<Window> for WindowContext<'_> {
3994 fn borrow_mut(&mut self) -> &mut Window {
3995 self.window
3996 }
3997}
3998
3999impl<T> BorrowWindow for T where T: BorrowMut<AppContext> + BorrowMut<Window> {}
4000
4001/// Provides access to application state that is specialized for a particular [`View`].
4002/// Allows you to interact with focus, emit events, etc.
4003/// ViewContext also derefs to [`WindowContext`], giving you access to all of its methods as well.
4004/// When you call [`View::update`], you're passed a `&mut V` and an `&mut ViewContext<V>`.
4005pub struct ViewContext<'a, V> {
4006 window_cx: WindowContext<'a>,
4007 view: &'a View<V>,
4008}
4009
4010impl<V> Borrow<AppContext> for ViewContext<'_, V> {
4011 fn borrow(&self) -> &AppContext {
4012 &*self.window_cx.app
4013 }
4014}
4015
4016impl<V> BorrowMut<AppContext> for ViewContext<'_, V> {
4017 fn borrow_mut(&mut self) -> &mut AppContext {
4018 &mut *self.window_cx.app
4019 }
4020}
4021
4022impl<V> Borrow<Window> for ViewContext<'_, V> {
4023 fn borrow(&self) -> &Window {
4024 &*self.window_cx.window
4025 }
4026}
4027
4028impl<V> BorrowMut<Window> for ViewContext<'_, V> {
4029 fn borrow_mut(&mut self) -> &mut Window {
4030 &mut *self.window_cx.window
4031 }
4032}
4033
4034impl<'a, V: 'static> ViewContext<'a, V> {
4035 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window, view: &'a View<V>) -> Self {
4036 Self {
4037 window_cx: WindowContext::new(app, window),
4038 view,
4039 }
4040 }
4041
4042 /// Get the entity_id of this view.
4043 pub fn entity_id(&self) -> EntityId {
4044 self.view.entity_id()
4045 }
4046
4047 /// Get the view pointer underlying this context.
4048 pub fn view(&self) -> &View<V> {
4049 self.view
4050 }
4051
4052 /// Get the model underlying this view.
4053 pub fn model(&self) -> &Model<V> {
4054 &self.view.model
4055 }
4056
4057 /// Access the underlying window context.
4058 pub fn window_context(&mut self) -> &mut WindowContext<'a> {
4059 &mut self.window_cx
4060 }
4061
4062 /// Sets a given callback to be run on the next frame.
4063 pub fn on_next_frame(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static)
4064 where
4065 V: 'static,
4066 {
4067 let view = self.view().clone();
4068 self.window_cx.on_next_frame(move |cx| view.update(cx, f));
4069 }
4070
4071 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
4072 /// that are currently on the stack to be returned to the app.
4073 pub fn defer(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static) {
4074 let view = self.view().downgrade();
4075 self.window_cx.defer(move |cx| {
4076 view.update(cx, f).ok();
4077 });
4078 }
4079
4080 /// Observe another model or view for changes to its state, as tracked by [`ModelContext::notify`].
4081 pub fn observe<V2, E>(
4082 &mut self,
4083 entity: &E,
4084 mut on_notify: impl FnMut(&mut V, E, &mut ViewContext<'_, V>) + 'static,
4085 ) -> Subscription
4086 where
4087 V2: 'static,
4088 V: 'static,
4089 E: Entity<V2>,
4090 {
4091 let view = self.view().downgrade();
4092 let entity_id = entity.entity_id();
4093 let entity = entity.downgrade();
4094 let window_handle = self.window.handle;
4095 self.app.new_observer(
4096 entity_id,
4097 Box::new(move |cx| {
4098 window_handle
4099 .update(cx, |_, cx| {
4100 if let Some(handle) = E::upgrade_from(&entity) {
4101 view.update(cx, |this, cx| on_notify(this, handle, cx))
4102 .is_ok()
4103 } else {
4104 false
4105 }
4106 })
4107 .unwrap_or(false)
4108 }),
4109 )
4110 }
4111
4112 /// Subscribe to events emitted by another model or view.
4113 /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
4114 /// 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.
4115 pub fn subscribe<V2, E, Evt>(
4116 &mut self,
4117 entity: &E,
4118 mut on_event: impl FnMut(&mut V, E, &Evt, &mut ViewContext<'_, V>) + 'static,
4119 ) -> Subscription
4120 where
4121 V2: EventEmitter<Evt>,
4122 E: Entity<V2>,
4123 Evt: 'static,
4124 {
4125 let view = self.view().downgrade();
4126 let entity_id = entity.entity_id();
4127 let handle = entity.downgrade();
4128 let window_handle = self.window.handle;
4129 self.app.new_subscription(
4130 entity_id,
4131 (
4132 TypeId::of::<Evt>(),
4133 Box::new(move |event, cx| {
4134 window_handle
4135 .update(cx, |_, cx| {
4136 if let Some(handle) = E::upgrade_from(&handle) {
4137 let event = event.downcast_ref().expect("invalid event type");
4138 view.update(cx, |this, cx| on_event(this, handle, event, cx))
4139 .is_ok()
4140 } else {
4141 false
4142 }
4143 })
4144 .unwrap_or(false)
4145 }),
4146 ),
4147 )
4148 }
4149
4150 /// Register a callback to be invoked when the view is released.
4151 ///
4152 /// The callback receives a handle to the view's window. This handle may be
4153 /// invalid, if the window was closed before the view was released.
4154 pub fn on_release(
4155 &mut self,
4156 on_release: impl FnOnce(&mut V, AnyWindowHandle, &mut AppContext) + 'static,
4157 ) -> Subscription {
4158 let window_handle = self.window.handle;
4159 let (subscription, activate) = self.app.release_listeners.insert(
4160 self.view.model.entity_id,
4161 Box::new(move |this, cx| {
4162 let this = this.downcast_mut().expect("invalid entity type");
4163 on_release(this, window_handle, cx)
4164 }),
4165 );
4166 activate();
4167 subscription
4168 }
4169
4170 /// Register a callback to be invoked when the given Model or View is released.
4171 pub fn observe_release<V2, E>(
4172 &mut self,
4173 entity: &E,
4174 mut on_release: impl FnMut(&mut V, &mut V2, &mut ViewContext<'_, V>) + 'static,
4175 ) -> Subscription
4176 where
4177 V: 'static,
4178 V2: 'static,
4179 E: Entity<V2>,
4180 {
4181 let view = self.view().downgrade();
4182 let entity_id = entity.entity_id();
4183 let window_handle = self.window.handle;
4184 let (subscription, activate) = self.app.release_listeners.insert(
4185 entity_id,
4186 Box::new(move |entity, cx| {
4187 let entity = entity.downcast_mut().expect("invalid entity type");
4188 let _ = window_handle.update(cx, |_, cx| {
4189 view.update(cx, |this, cx| on_release(this, entity, cx))
4190 });
4191 }),
4192 );
4193 activate();
4194 subscription
4195 }
4196
4197 /// Indicate that this view has changed, which will invoke any observers and also mark the window as dirty.
4198 /// If this view or any of its ancestors are *cached*, notifying it will cause it or its ancestors to be redrawn.
4199 pub fn notify(&mut self) {
4200 self.window_cx.notify(self.view.entity_id());
4201 }
4202
4203 /// Register a callback to be invoked when the window is resized.
4204 pub fn observe_window_bounds(
4205 &mut self,
4206 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4207 ) -> Subscription {
4208 let view = self.view.downgrade();
4209 let (subscription, activate) = self.window.bounds_observers.insert(
4210 (),
4211 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
4212 );
4213 activate();
4214 subscription
4215 }
4216
4217 /// Register a callback to be invoked when the window is activated or deactivated.
4218 pub fn observe_window_activation(
4219 &mut self,
4220 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4221 ) -> Subscription {
4222 let view = self.view.downgrade();
4223 let (subscription, activate) = self.window.activation_observers.insert(
4224 (),
4225 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
4226 );
4227 activate();
4228 subscription
4229 }
4230
4231 /// Registers a callback to be invoked when the window appearance changes.
4232 pub fn observe_window_appearance(
4233 &mut self,
4234 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4235 ) -> Subscription {
4236 let view = self.view.downgrade();
4237 let (subscription, activate) = self.window.appearance_observers.insert(
4238 (),
4239 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
4240 );
4241 activate();
4242 subscription
4243 }
4244
4245 /// Register a callback to be invoked when the window's pending input changes.
4246 pub fn observe_pending_input(
4247 &mut self,
4248 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4249 ) -> Subscription {
4250 let view = self.view.downgrade();
4251 let (subscription, activate) = self.window.pending_input_observers.insert(
4252 (),
4253 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
4254 );
4255 activate();
4256 subscription
4257 }
4258
4259 /// Register a listener to be called when the given focus handle receives focus.
4260 /// Returns a subscription and persists until the subscription is dropped.
4261 pub fn on_focus(
4262 &mut self,
4263 handle: &FocusHandle,
4264 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4265 ) -> Subscription {
4266 let view = self.view.downgrade();
4267 let focus_id = handle.id;
4268 let (subscription, activate) =
4269 self.window.new_focus_listener(Box::new(move |event, cx| {
4270 view.update(cx, |view, cx| {
4271 if event.previous_focus_path.last() != Some(&focus_id)
4272 && event.current_focus_path.last() == Some(&focus_id)
4273 {
4274 listener(view, cx)
4275 }
4276 })
4277 .is_ok()
4278 }));
4279 self.app.defer(|_| activate());
4280 subscription
4281 }
4282
4283 /// Register a listener to be called when the given focus handle or one of its descendants receives focus.
4284 /// This does not fire if the given focus handle - or one of its descendants - was previously focused.
4285 /// Returns a subscription and persists until the subscription is dropped.
4286 pub fn on_focus_in(
4287 &mut self,
4288 handle: &FocusHandle,
4289 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4290 ) -> Subscription {
4291 let view = self.view.downgrade();
4292 let focus_id = handle.id;
4293 let (subscription, activate) =
4294 self.window.new_focus_listener(Box::new(move |event, cx| {
4295 view.update(cx, |view, cx| {
4296 if event.is_focus_in(focus_id) {
4297 listener(view, cx)
4298 }
4299 })
4300 .is_ok()
4301 }));
4302 self.app.defer(move |_| activate());
4303 subscription
4304 }
4305
4306 /// Register a listener to be called when the given focus handle loses focus.
4307 /// Returns a subscription and persists until the subscription is dropped.
4308 pub fn on_blur(
4309 &mut self,
4310 handle: &FocusHandle,
4311 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4312 ) -> Subscription {
4313 let view = self.view.downgrade();
4314 let focus_id = handle.id;
4315 let (subscription, activate) =
4316 self.window.new_focus_listener(Box::new(move |event, cx| {
4317 view.update(cx, |view, cx| {
4318 if event.previous_focus_path.last() == Some(&focus_id)
4319 && event.current_focus_path.last() != Some(&focus_id)
4320 {
4321 listener(view, cx)
4322 }
4323 })
4324 .is_ok()
4325 }));
4326 self.app.defer(move |_| activate());
4327 subscription
4328 }
4329
4330 /// Register a listener to be called when nothing in the window has focus.
4331 /// This typically happens when the node that was focused is removed from the tree,
4332 /// and this callback lets you chose a default place to restore the users focus.
4333 /// Returns a subscription and persists until the subscription is dropped.
4334 pub fn on_focus_lost(
4335 &mut self,
4336 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4337 ) -> Subscription {
4338 let view = self.view.downgrade();
4339 let (subscription, activate) = self.window.focus_lost_listeners.insert(
4340 (),
4341 Box::new(move |cx| view.update(cx, |view, cx| listener(view, cx)).is_ok()),
4342 );
4343 activate();
4344 subscription
4345 }
4346
4347 /// Register a listener to be called when the given focus handle or one of its descendants loses focus.
4348 /// Returns a subscription and persists until the subscription is dropped.
4349 pub fn on_focus_out(
4350 &mut self,
4351 handle: &FocusHandle,
4352 mut listener: impl FnMut(&mut V, FocusOutEvent, &mut ViewContext<V>) + 'static,
4353 ) -> Subscription {
4354 let view = self.view.downgrade();
4355 let focus_id = handle.id;
4356 let (subscription, activate) =
4357 self.window.new_focus_listener(Box::new(move |event, cx| {
4358 view.update(cx, |view, cx| {
4359 if let Some(blurred_id) = event.previous_focus_path.last().copied() {
4360 if event.is_focus_out(focus_id) {
4361 let event = FocusOutEvent {
4362 blurred: WeakFocusHandle {
4363 id: blurred_id,
4364 handles: Arc::downgrade(&cx.window.focus_handles),
4365 },
4366 };
4367 listener(view, event, cx)
4368 }
4369 }
4370 })
4371 .is_ok()
4372 }));
4373 self.app.defer(move |_| activate());
4374 subscription
4375 }
4376
4377 /// Schedule a future to be run asynchronously.
4378 /// The given callback is invoked with a [`WeakView<V>`] to avoid leaking the view for a long-running process.
4379 /// It's also given an [`AsyncWindowContext`], which can be used to access the state of the view across await points.
4380 /// The returned future will be polled on the main thread.
4381 pub fn spawn<Fut, R>(
4382 &mut self,
4383 f: impl FnOnce(WeakView<V>, AsyncWindowContext) -> Fut,
4384 ) -> Task<R>
4385 where
4386 R: 'static,
4387 Fut: Future<Output = R> + 'static,
4388 {
4389 let view = self.view().downgrade();
4390 self.window_cx.spawn(|cx| f(view, cx))
4391 }
4392
4393 /// Register a callback to be invoked when the given global state changes.
4394 pub fn observe_global<G: Global>(
4395 &mut self,
4396 mut f: impl FnMut(&mut V, &mut ViewContext<'_, V>) + 'static,
4397 ) -> Subscription {
4398 let window_handle = self.window.handle;
4399 let view = self.view().downgrade();
4400 let (subscription, activate) = self.global_observers.insert(
4401 TypeId::of::<G>(),
4402 Box::new(move |cx| {
4403 window_handle
4404 .update(cx, |_, cx| view.update(cx, |view, cx| f(view, cx)).is_ok())
4405 .unwrap_or(false)
4406 }),
4407 );
4408 self.app.defer(move |_| activate());
4409 subscription
4410 }
4411
4412 /// Register a callback to be invoked when the given Action type is dispatched to the window.
4413 pub fn on_action(
4414 &mut self,
4415 action_type: TypeId,
4416 listener: impl Fn(&mut V, &dyn Any, DispatchPhase, &mut ViewContext<V>) + 'static,
4417 ) {
4418 let handle = self.view().clone();
4419 self.window_cx
4420 .on_action(action_type, move |action, phase, cx| {
4421 handle.update(cx, |view, cx| {
4422 listener(view, action, phase, cx);
4423 })
4424 });
4425 }
4426
4427 /// Emit an event to be handled by any other views that have subscribed via [ViewContext::subscribe].
4428 pub fn emit<Evt>(&mut self, event: Evt)
4429 where
4430 Evt: 'static,
4431 V: EventEmitter<Evt>,
4432 {
4433 let emitter = self.view.model.entity_id;
4434 self.app.push_effect(Effect::Emit {
4435 emitter,
4436 event_type: TypeId::of::<Evt>(),
4437 event: Box::new(event),
4438 });
4439 }
4440
4441 /// Move focus to the current view, assuming it implements [`FocusableView`].
4442 pub fn focus_self(&mut self)
4443 where
4444 V: FocusableView,
4445 {
4446 self.defer(|view, cx| view.focus_handle(cx).focus(cx))
4447 }
4448
4449 /// Convenience method for accessing view state in an event callback.
4450 ///
4451 /// Many GPUI callbacks take the form of `Fn(&E, &mut WindowContext)`,
4452 /// but it's often useful to be able to access view state in these
4453 /// callbacks. This method provides a convenient way to do so.
4454 pub fn listener<E>(
4455 &self,
4456 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
4457 ) -> impl Fn(&E, &mut WindowContext) + 'static {
4458 let view = self.view().downgrade();
4459 move |e: &E, cx: &mut WindowContext| {
4460 view.update(cx, |view, cx| f(view, e, cx)).ok();
4461 }
4462 }
4463}
4464
4465impl<V> Context for ViewContext<'_, V> {
4466 type Result<U> = U;
4467
4468 fn new_model<T: 'static>(
4469 &mut self,
4470 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
4471 ) -> Model<T> {
4472 self.window_cx.new_model(build_model)
4473 }
4474
4475 fn reserve_model<T: 'static>(&mut self) -> Self::Result<crate::Reservation<T>> {
4476 self.window_cx.reserve_model()
4477 }
4478
4479 fn insert_model<T: 'static>(
4480 &mut self,
4481 reservation: crate::Reservation<T>,
4482 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
4483 ) -> Self::Result<Model<T>> {
4484 self.window_cx.insert_model(reservation, build_model)
4485 }
4486
4487 fn update_model<T: 'static, R>(
4488 &mut self,
4489 model: &Model<T>,
4490 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
4491 ) -> R {
4492 self.window_cx.update_model(model, update)
4493 }
4494
4495 fn read_model<T, R>(
4496 &self,
4497 handle: &Model<T>,
4498 read: impl FnOnce(&T, &AppContext) -> R,
4499 ) -> Self::Result<R>
4500 where
4501 T: 'static,
4502 {
4503 self.window_cx.read_model(handle, read)
4504 }
4505
4506 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
4507 where
4508 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
4509 {
4510 self.window_cx.update_window(window, update)
4511 }
4512
4513 fn read_window<T, R>(
4514 &self,
4515 window: &WindowHandle<T>,
4516 read: impl FnOnce(View<T>, &AppContext) -> R,
4517 ) -> Result<R>
4518 where
4519 T: 'static,
4520 {
4521 self.window_cx.read_window(window, read)
4522 }
4523}
4524
4525impl<V: 'static> VisualContext for ViewContext<'_, V> {
4526 fn new_view<W: Render + 'static>(
4527 &mut self,
4528 build_view_state: impl FnOnce(&mut ViewContext<'_, W>) -> W,
4529 ) -> Self::Result<View<W>> {
4530 self.window_cx.new_view(build_view_state)
4531 }
4532
4533 fn update_view<V2: 'static, R>(
4534 &mut self,
4535 view: &View<V2>,
4536 update: impl FnOnce(&mut V2, &mut ViewContext<'_, V2>) -> R,
4537 ) -> Self::Result<R> {
4538 self.window_cx.update_view(view, update)
4539 }
4540
4541 fn replace_root_view<W>(
4542 &mut self,
4543 build_view: impl FnOnce(&mut ViewContext<'_, W>) -> W,
4544 ) -> Self::Result<View<W>>
4545 where
4546 W: 'static + Render,
4547 {
4548 self.window_cx.replace_root_view(build_view)
4549 }
4550
4551 fn focus_view<W: FocusableView>(&mut self, view: &View<W>) -> Self::Result<()> {
4552 self.window_cx.focus_view(view)
4553 }
4554
4555 fn dismiss_view<W: ManagedView>(&mut self, view: &View<W>) -> Self::Result<()> {
4556 self.window_cx.dismiss_view(view)
4557 }
4558}
4559
4560impl<'a, V> std::ops::Deref for ViewContext<'a, V> {
4561 type Target = WindowContext<'a>;
4562
4563 fn deref(&self) -> &Self::Target {
4564 &self.window_cx
4565 }
4566}
4567
4568impl<'a, V> std::ops::DerefMut for ViewContext<'a, V> {
4569 fn deref_mut(&mut self) -> &mut Self::Target {
4570 &mut self.window_cx
4571 }
4572}
4573
4574// #[derive(Clone, Copy, Eq, PartialEq, Hash)]
4575slotmap::new_key_type! {
4576 /// A unique identifier for a window.
4577 pub struct WindowId;
4578}
4579
4580impl WindowId {
4581 /// Converts this window ID to a `u64`.
4582 pub fn as_u64(&self) -> u64 {
4583 self.0.as_ffi()
4584 }
4585}
4586
4587/// A handle to a window with a specific root view type.
4588/// Note that this does not keep the window alive on its own.
4589#[derive(Deref, DerefMut)]
4590pub struct WindowHandle<V> {
4591 #[deref]
4592 #[deref_mut]
4593 pub(crate) any_handle: AnyWindowHandle,
4594 state_type: PhantomData<V>,
4595}
4596
4597impl<V: 'static + Render> WindowHandle<V> {
4598 /// Creates a new handle from a window ID.
4599 /// This does not check if the root type of the window is `V`.
4600 pub fn new(id: WindowId) -> Self {
4601 WindowHandle {
4602 any_handle: AnyWindowHandle {
4603 id,
4604 state_type: TypeId::of::<V>(),
4605 },
4606 state_type: PhantomData,
4607 }
4608 }
4609
4610 /// Get the root view out of this window.
4611 ///
4612 /// This will fail if the window is closed or if the root view's type does not match `V`.
4613 pub fn root<C>(&self, cx: &mut C) -> Result<View<V>>
4614 where
4615 C: Context,
4616 {
4617 Flatten::flatten(cx.update_window(self.any_handle, |root_view, _| {
4618 root_view
4619 .downcast::<V>()
4620 .map_err(|_| anyhow!("the type of the window's root view has changed"))
4621 }))
4622 }
4623
4624 /// Updates the root view of this window.
4625 ///
4626 /// This will fail if the window has been closed or if the root view's type does not match
4627 pub fn update<C, R>(
4628 &self,
4629 cx: &mut C,
4630 update: impl FnOnce(&mut V, &mut ViewContext<'_, V>) -> R,
4631 ) -> Result<R>
4632 where
4633 C: Context,
4634 {
4635 cx.update_window(self.any_handle, |root_view, cx| {
4636 let view = root_view
4637 .downcast::<V>()
4638 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
4639 Ok(cx.update_view(&view, update))
4640 })?
4641 }
4642
4643 /// Read the root view out of this window.
4644 ///
4645 /// This will fail if the window is closed or if the root view's type does not match `V`.
4646 pub fn read<'a>(&self, cx: &'a AppContext) -> Result<&'a V> {
4647 let x = cx
4648 .windows
4649 .get(self.id)
4650 .and_then(|window| {
4651 window
4652 .as_ref()
4653 .and_then(|window| window.root_view.clone())
4654 .map(|root_view| root_view.downcast::<V>())
4655 })
4656 .ok_or_else(|| anyhow!("window not found"))?
4657 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
4658
4659 Ok(x.read(cx))
4660 }
4661
4662 /// Read the root view out of this window, with a callback
4663 ///
4664 /// This will fail if the window is closed or if the root view's type does not match `V`.
4665 pub fn read_with<C, R>(&self, cx: &C, read_with: impl FnOnce(&V, &AppContext) -> R) -> Result<R>
4666 where
4667 C: Context,
4668 {
4669 cx.read_window(self, |root_view, cx| read_with(root_view.read(cx), cx))
4670 }
4671
4672 /// Read the root view pointer off of this window.
4673 ///
4674 /// This will fail if the window is closed or if the root view's type does not match `V`.
4675 pub fn root_view<C>(&self, cx: &C) -> Result<View<V>>
4676 where
4677 C: Context,
4678 {
4679 cx.read_window(self, |root_view, _cx| root_view.clone())
4680 }
4681
4682 /// Check if this window is 'active'.
4683 ///
4684 /// Will return `None` if the window is closed or currently
4685 /// borrowed.
4686 pub fn is_active(&self, cx: &mut AppContext) -> Option<bool> {
4687 cx.update_window(self.any_handle, |_, cx| cx.is_window_active())
4688 .ok()
4689 }
4690}
4691
4692impl<V> Copy for WindowHandle<V> {}
4693
4694impl<V> Clone for WindowHandle<V> {
4695 fn clone(&self) -> Self {
4696 *self
4697 }
4698}
4699
4700impl<V> PartialEq for WindowHandle<V> {
4701 fn eq(&self, other: &Self) -> bool {
4702 self.any_handle == other.any_handle
4703 }
4704}
4705
4706impl<V> Eq for WindowHandle<V> {}
4707
4708impl<V> Hash for WindowHandle<V> {
4709 fn hash<H: Hasher>(&self, state: &mut H) {
4710 self.any_handle.hash(state);
4711 }
4712}
4713
4714impl<V: 'static> From<WindowHandle<V>> for AnyWindowHandle {
4715 fn from(val: WindowHandle<V>) -> Self {
4716 val.any_handle
4717 }
4718}
4719
4720unsafe impl<V> Send for WindowHandle<V> {}
4721unsafe impl<V> Sync for WindowHandle<V> {}
4722
4723/// A handle to a window with any root view type, which can be downcast to a window with a specific root view type.
4724#[derive(Copy, Clone, PartialEq, Eq, Hash)]
4725pub struct AnyWindowHandle {
4726 pub(crate) id: WindowId,
4727 state_type: TypeId,
4728}
4729
4730impl AnyWindowHandle {
4731 /// Get the ID of this window.
4732 pub fn window_id(&self) -> WindowId {
4733 self.id
4734 }
4735
4736 /// Attempt to convert this handle to a window handle with a specific root view type.
4737 /// If the types do not match, this will return `None`.
4738 pub fn downcast<T: 'static>(&self) -> Option<WindowHandle<T>> {
4739 if TypeId::of::<T>() == self.state_type {
4740 Some(WindowHandle {
4741 any_handle: *self,
4742 state_type: PhantomData,
4743 })
4744 } else {
4745 None
4746 }
4747 }
4748
4749 /// Updates the state of the root view of this window.
4750 ///
4751 /// This will fail if the window has been closed.
4752 pub fn update<C, R>(
4753 self,
4754 cx: &mut C,
4755 update: impl FnOnce(AnyView, &mut WindowContext<'_>) -> R,
4756 ) -> Result<R>
4757 where
4758 C: Context,
4759 {
4760 cx.update_window(self, update)
4761 }
4762
4763 /// Read the state of the root view of this window.
4764 ///
4765 /// This will fail if the window has been closed.
4766 pub fn read<T, C, R>(self, cx: &C, read: impl FnOnce(View<T>, &AppContext) -> R) -> Result<R>
4767 where
4768 C: Context,
4769 T: 'static,
4770 {
4771 let view = self
4772 .downcast::<T>()
4773 .context("the type of the window's root view has changed")?;
4774
4775 cx.read_window(&view, read)
4776 }
4777}
4778
4779/// An identifier for an [`Element`](crate::Element).
4780///
4781/// Can be constructed with a string, a number, or both, as well
4782/// as other internal representations.
4783#[derive(Clone, Debug, Eq, PartialEq, Hash)]
4784pub enum ElementId {
4785 /// The ID of a View element
4786 View(EntityId),
4787 /// An integer ID.
4788 Integer(usize),
4789 /// A string based ID.
4790 Name(SharedString),
4791 /// A UUID.
4792 Uuid(Uuid),
4793 /// An ID that's equated with a focus handle.
4794 FocusHandle(FocusId),
4795 /// A combination of a name and an integer.
4796 NamedInteger(SharedString, usize),
4797}
4798
4799impl Display for ElementId {
4800 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
4801 match self {
4802 ElementId::View(entity_id) => write!(f, "view-{}", entity_id)?,
4803 ElementId::Integer(ix) => write!(f, "{}", ix)?,
4804 ElementId::Name(name) => write!(f, "{}", name)?,
4805 ElementId::FocusHandle(_) => write!(f, "FocusHandle")?,
4806 ElementId::NamedInteger(s, i) => write!(f, "{}-{}", s, i)?,
4807 ElementId::Uuid(uuid) => write!(f, "{}", uuid)?,
4808 }
4809
4810 Ok(())
4811 }
4812}
4813
4814impl TryInto<SharedString> for ElementId {
4815 type Error = anyhow::Error;
4816
4817 fn try_into(self) -> anyhow::Result<SharedString> {
4818 if let ElementId::Name(name) = self {
4819 Ok(name)
4820 } else {
4821 Err(anyhow!("element id is not string"))
4822 }
4823 }
4824}
4825
4826impl From<usize> for ElementId {
4827 fn from(id: usize) -> Self {
4828 ElementId::Integer(id)
4829 }
4830}
4831
4832impl From<i32> for ElementId {
4833 fn from(id: i32) -> Self {
4834 Self::Integer(id as usize)
4835 }
4836}
4837
4838impl From<SharedString> for ElementId {
4839 fn from(name: SharedString) -> Self {
4840 ElementId::Name(name)
4841 }
4842}
4843
4844impl From<&'static str> for ElementId {
4845 fn from(name: &'static str) -> Self {
4846 ElementId::Name(name.into())
4847 }
4848}
4849
4850impl<'a> From<&'a FocusHandle> for ElementId {
4851 fn from(handle: &'a FocusHandle) -> Self {
4852 ElementId::FocusHandle(handle.id)
4853 }
4854}
4855
4856impl From<(&'static str, EntityId)> for ElementId {
4857 fn from((name, id): (&'static str, EntityId)) -> Self {
4858 ElementId::NamedInteger(name.into(), id.as_u64() as usize)
4859 }
4860}
4861
4862impl From<(&'static str, usize)> for ElementId {
4863 fn from((name, id): (&'static str, usize)) -> Self {
4864 ElementId::NamedInteger(name.into(), id)
4865 }
4866}
4867
4868impl From<(&'static str, u64)> for ElementId {
4869 fn from((name, id): (&'static str, u64)) -> Self {
4870 ElementId::NamedInteger(name.into(), id as usize)
4871 }
4872}
4873
4874impl From<Uuid> for ElementId {
4875 fn from(value: Uuid) -> Self {
4876 Self::Uuid(value)
4877 }
4878}
4879
4880impl From<(&'static str, u32)> for ElementId {
4881 fn from((name, id): (&'static str, u32)) -> Self {
4882 ElementId::NamedInteger(name.into(), id as usize)
4883 }
4884}
4885
4886/// A rectangle to be rendered in the window at the given position and size.
4887/// Passed as an argument [`WindowContext::paint_quad`].
4888#[derive(Clone)]
4889pub struct PaintQuad {
4890 /// The bounds of the quad within the window.
4891 pub bounds: Bounds<Pixels>,
4892 /// The radii of the quad's corners.
4893 pub corner_radii: Corners<Pixels>,
4894 /// The background color of the quad.
4895 pub background: Hsla,
4896 /// The widths of the quad's borders.
4897 pub border_widths: Edges<Pixels>,
4898 /// The color of the quad's borders.
4899 pub border_color: Hsla,
4900}
4901
4902impl PaintQuad {
4903 /// Sets the corner radii of the quad.
4904 pub fn corner_radii(self, corner_radii: impl Into<Corners<Pixels>>) -> Self {
4905 PaintQuad {
4906 corner_radii: corner_radii.into(),
4907 ..self
4908 }
4909 }
4910
4911 /// Sets the border widths of the quad.
4912 pub fn border_widths(self, border_widths: impl Into<Edges<Pixels>>) -> Self {
4913 PaintQuad {
4914 border_widths: border_widths.into(),
4915 ..self
4916 }
4917 }
4918
4919 /// Sets the border color of the quad.
4920 pub fn border_color(self, border_color: impl Into<Hsla>) -> Self {
4921 PaintQuad {
4922 border_color: border_color.into(),
4923 ..self
4924 }
4925 }
4926
4927 /// Sets the background color of the quad.
4928 pub fn background(self, background: impl Into<Hsla>) -> Self {
4929 PaintQuad {
4930 background: background.into(),
4931 ..self
4932 }
4933 }
4934}
4935
4936/// Creates a quad with the given parameters.
4937pub fn quad(
4938 bounds: Bounds<Pixels>,
4939 corner_radii: impl Into<Corners<Pixels>>,
4940 background: impl Into<Hsla>,
4941 border_widths: impl Into<Edges<Pixels>>,
4942 border_color: impl Into<Hsla>,
4943) -> PaintQuad {
4944 PaintQuad {
4945 bounds,
4946 corner_radii: corner_radii.into(),
4947 background: background.into(),
4948 border_widths: border_widths.into(),
4949 border_color: border_color.into(),
4950 }
4951}
4952
4953/// Creates a filled quad with the given bounds and background color.
4954pub fn fill(bounds: impl Into<Bounds<Pixels>>, background: impl Into<Hsla>) -> PaintQuad {
4955 PaintQuad {
4956 bounds: bounds.into(),
4957 corner_radii: (0.).into(),
4958 background: background.into(),
4959 border_widths: (0.).into(),
4960 border_color: transparent_black(),
4961 }
4962}
4963
4964/// Creates a rectangle outline with the given bounds, border color, and a 1px border width
4965pub fn outline(bounds: impl Into<Bounds<Pixels>>, border_color: impl Into<Hsla>) -> PaintQuad {
4966 PaintQuad {
4967 bounds: bounds.into(),
4968 corner_radii: (0.).into(),
4969 background: transparent_black(),
4970 border_widths: (1.).into(),
4971 border_color: border_color.into(),
4972 }
4973}