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, GPUSpecs, Global, GlobalElementId, GlyphId, Hsla, ImageData,
7 InputHandler, IsZero, KeyBinding, KeyContext, KeyDownEvent, KeyEvent, Keystroke,
8 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, Replay, ResizeEdge, ScaledPixels, Scene, Shadow,
13 SharedString, Size, StrikethroughStyle, Style, SubscriberSet, Subscription, TaffyLayoutEngine,
14 Task, 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 self.focus = None;
468 }
469
470 pub(crate) fn hit_test(&self, position: Point<Pixels>) -> HitTest {
471 let mut hit_test = HitTest::default();
472 for hitbox in self.hitboxes.iter().rev() {
473 let bounds = hitbox.bounds.intersect(&hitbox.content_mask.bounds);
474 if bounds.contains(&position) {
475 hit_test.0.push(hitbox.id);
476 if hitbox.opaque {
477 break;
478 }
479 }
480 }
481 hit_test
482 }
483
484 pub(crate) fn focus_path(&self) -> SmallVec<[FocusId; 8]> {
485 self.focus
486 .map(|focus_id| self.dispatch_tree.focus_path(focus_id))
487 .unwrap_or_default()
488 }
489
490 pub(crate) fn finish(&mut self, prev_frame: &mut Self) {
491 for element_state_key in &self.accessed_element_states {
492 if let Some((element_state_key, element_state)) =
493 prev_frame.element_states.remove_entry(element_state_key)
494 {
495 self.element_states.insert(element_state_key, element_state);
496 }
497 }
498
499 self.scene.finish();
500 }
501}
502
503// Holds the state for a specific window.
504#[doc(hidden)]
505pub struct Window {
506 pub(crate) handle: AnyWindowHandle,
507 pub(crate) removed: bool,
508 pub(crate) platform_window: Box<dyn PlatformWindow>,
509 display_id: Option<DisplayId>,
510 sprite_atlas: Arc<dyn PlatformAtlas>,
511 text_system: Arc<WindowTextSystem>,
512 rem_size: Pixels,
513 /// The stack of override values for the window's rem size.
514 ///
515 /// This is used by `with_rem_size` to allow rendering an element tree with
516 /// a given rem size.
517 rem_size_override_stack: SmallVec<[Pixels; 8]>,
518 pub(crate) viewport_size: Size<Pixels>,
519 layout_engine: Option<TaffyLayoutEngine>,
520 pub(crate) root_view: Option<AnyView>,
521 pub(crate) element_id_stack: SmallVec<[ElementId; 32]>,
522 pub(crate) text_style_stack: Vec<TextStyleRefinement>,
523 pub(crate) element_offset_stack: Vec<Point<Pixels>>,
524 pub(crate) content_mask_stack: Vec<ContentMask<Pixels>>,
525 pub(crate) requested_autoscroll: Option<Bounds<Pixels>>,
526 pub(crate) rendered_frame: Frame,
527 pub(crate) next_frame: Frame,
528 pub(crate) next_hitbox_id: HitboxId,
529 pub(crate) next_tooltip_id: TooltipId,
530 pub(crate) tooltip_bounds: Option<TooltipBounds>,
531 next_frame_callbacks: Rc<RefCell<Vec<FrameCallback>>>,
532 pub(crate) dirty_views: FxHashSet<EntityId>,
533 pub(crate) focus_handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
534 focus_listeners: SubscriberSet<(), AnyWindowFocusListener>,
535 focus_lost_listeners: SubscriberSet<(), AnyObserver>,
536 default_prevented: bool,
537 mouse_position: Point<Pixels>,
538 mouse_hit_test: HitTest,
539 modifiers: Modifiers,
540 scale_factor: f32,
541 bounds_observers: SubscriberSet<(), AnyObserver>,
542 appearance: WindowAppearance,
543 appearance_observers: SubscriberSet<(), AnyObserver>,
544 active: Rc<Cell<bool>>,
545 hovered: Rc<Cell<bool>>,
546 pub(crate) dirty: Rc<Cell<bool>>,
547 pub(crate) needs_present: Rc<Cell<bool>>,
548 pub(crate) last_input_timestamp: Rc<Cell<Instant>>,
549 pub(crate) refreshing: bool,
550 pub(crate) draw_phase: DrawPhase,
551 activation_observers: SubscriberSet<(), AnyObserver>,
552 pub(crate) focus: Option<FocusId>,
553 focus_enabled: bool,
554 pending_input: Option<PendingInput>,
555 pending_modifier: ModifierState,
556 pending_input_observers: SubscriberSet<(), AnyObserver>,
557 prompt: Option<RenderablePromptHandle>,
558}
559
560#[derive(Clone, Debug, Default)]
561struct ModifierState {
562 modifiers: Modifiers,
563 saw_keystroke: bool,
564}
565
566#[derive(Clone, Copy, Debug, Eq, PartialEq)]
567pub(crate) enum DrawPhase {
568 None,
569 Prepaint,
570 Paint,
571 Focus,
572}
573
574#[derive(Default, Debug)]
575struct PendingInput {
576 keystrokes: SmallVec<[Keystroke; 1]>,
577 focus: Option<FocusId>,
578 timer: Option<Task<()>>,
579}
580
581pub(crate) struct ElementStateBox {
582 pub(crate) inner: Box<dyn Any>,
583 #[cfg(debug_assertions)]
584 pub(crate) type_name: &'static str,
585}
586
587fn default_bounds(display_id: Option<DisplayId>, cx: &mut AppContext) -> Bounds<Pixels> {
588 const DEFAULT_WINDOW_OFFSET: Point<Pixels> = point(px(0.), px(35.));
589
590 cx.active_window()
591 .and_then(|w| w.update(cx, |_, cx| cx.bounds()).ok())
592 .map(|mut bounds| {
593 bounds.origin += DEFAULT_WINDOW_OFFSET;
594 bounds
595 })
596 .unwrap_or_else(|| {
597 let display = display_id
598 .map(|id| cx.find_display(id))
599 .unwrap_or_else(|| cx.primary_display());
600
601 display
602 .map(|display| display.default_bounds())
603 .unwrap_or_else(|| Bounds::new(point(px(0.), px(0.)), DEFAULT_WINDOW_SIZE))
604 })
605}
606
607impl Window {
608 pub(crate) fn new(
609 handle: AnyWindowHandle,
610 options: WindowOptions,
611 cx: &mut AppContext,
612 ) -> Result<Self> {
613 let WindowOptions {
614 window_bounds,
615 titlebar,
616 focus,
617 show,
618 kind,
619 is_movable,
620 display_id,
621 window_background,
622 app_id,
623 window_min_size,
624 window_decorations,
625 } = options;
626
627 let bounds = window_bounds
628 .map(|bounds| bounds.get_bounds())
629 .unwrap_or_else(|| default_bounds(display_id, cx));
630 let mut platform_window = cx.platform.open_window(
631 handle,
632 WindowParams {
633 bounds,
634 titlebar,
635 kind,
636 is_movable,
637 focus,
638 show,
639 display_id,
640 window_min_size,
641 },
642 )?;
643 let display_id = platform_window.display().map(|display| display.id());
644 let sprite_atlas = platform_window.sprite_atlas();
645 let mouse_position = platform_window.mouse_position();
646 let modifiers = platform_window.modifiers();
647 let content_size = platform_window.content_size();
648 let scale_factor = platform_window.scale_factor();
649 let appearance = platform_window.appearance();
650 let text_system = Arc::new(WindowTextSystem::new(cx.text_system().clone()));
651 let dirty = Rc::new(Cell::new(true));
652 let active = Rc::new(Cell::new(platform_window.is_active()));
653 let hovered = Rc::new(Cell::new(platform_window.is_hovered()));
654 let needs_present = Rc::new(Cell::new(false));
655 let next_frame_callbacks: Rc<RefCell<Vec<FrameCallback>>> = Default::default();
656 let last_input_timestamp = Rc::new(Cell::new(Instant::now()));
657
658 platform_window
659 .request_decorations(window_decorations.unwrap_or(WindowDecorations::Server));
660 platform_window.set_background_appearance(window_background);
661
662 if let Some(ref window_open_state) = window_bounds {
663 match window_open_state {
664 WindowBounds::Fullscreen(_) => platform_window.toggle_fullscreen(),
665 WindowBounds::Maximized(_) => platform_window.zoom(),
666 WindowBounds::Windowed(_) => {}
667 }
668 }
669
670 platform_window.on_close(Box::new({
671 let mut cx = cx.to_async();
672 move || {
673 let _ = handle.update(&mut cx, |_, cx| cx.remove_window());
674 }
675 }));
676 platform_window.on_request_frame(Box::new({
677 let mut cx = cx.to_async();
678 let dirty = dirty.clone();
679 let active = active.clone();
680 let needs_present = needs_present.clone();
681 let next_frame_callbacks = next_frame_callbacks.clone();
682 let last_input_timestamp = last_input_timestamp.clone();
683 move || {
684 let next_frame_callbacks = next_frame_callbacks.take();
685 if !next_frame_callbacks.is_empty() {
686 handle
687 .update(&mut cx, |_, cx| {
688 for callback in next_frame_callbacks {
689 callback(cx);
690 }
691 })
692 .log_err();
693 }
694
695 // Keep presenting the current scene for 1 extra second since the
696 // last input to prevent the display from underclocking the refresh rate.
697 let needs_present = needs_present.get()
698 || (active.get()
699 && last_input_timestamp.get().elapsed() < Duration::from_secs(1));
700
701 if dirty.get() {
702 measure("frame duration", || {
703 handle
704 .update(&mut cx, |_, cx| {
705 cx.draw();
706 cx.present();
707 })
708 .log_err();
709 })
710 } else if needs_present {
711 handle.update(&mut cx, |_, cx| cx.present()).log_err();
712 }
713
714 handle
715 .update(&mut cx, |_, cx| {
716 cx.complete_frame();
717 })
718 .log_err();
719 }
720 }));
721 platform_window.on_resize(Box::new({
722 let mut cx = cx.to_async();
723 move |_, _| {
724 handle
725 .update(&mut cx, |_, cx| cx.bounds_changed())
726 .log_err();
727 }
728 }));
729 platform_window.on_moved(Box::new({
730 let mut cx = cx.to_async();
731 move || {
732 handle
733 .update(&mut cx, |_, cx| cx.bounds_changed())
734 .log_err();
735 }
736 }));
737 platform_window.on_appearance_changed(Box::new({
738 let mut cx = cx.to_async();
739 move || {
740 handle
741 .update(&mut cx, |_, cx| cx.appearance_changed())
742 .log_err();
743 }
744 }));
745 platform_window.on_active_status_change(Box::new({
746 let mut cx = cx.to_async();
747 move |active| {
748 handle
749 .update(&mut cx, |_, cx| {
750 cx.window.active.set(active);
751 cx.window
752 .activation_observers
753 .clone()
754 .retain(&(), |callback| callback(cx));
755 cx.refresh();
756 })
757 .log_err();
758 }
759 }));
760 platform_window.on_hover_status_change(Box::new({
761 let mut cx = cx.to_async();
762 move |active| {
763 handle
764 .update(&mut cx, |_, cx| {
765 cx.window.hovered.set(active);
766 cx.refresh();
767 })
768 .log_err();
769 }
770 }));
771 platform_window.on_input({
772 let mut cx = cx.to_async();
773 Box::new(move |event| {
774 handle
775 .update(&mut cx, |_, cx| cx.dispatch_event(event))
776 .log_err()
777 .unwrap_or(DispatchEventResult::default())
778 })
779 });
780
781 if let Some(app_id) = app_id {
782 platform_window.set_app_id(&app_id);
783 }
784
785 Ok(Window {
786 handle,
787 removed: false,
788 platform_window,
789 display_id,
790 sprite_atlas,
791 text_system,
792 rem_size: px(16.),
793 rem_size_override_stack: SmallVec::new(),
794 viewport_size: content_size,
795 layout_engine: Some(TaffyLayoutEngine::new()),
796 root_view: None,
797 element_id_stack: SmallVec::default(),
798 text_style_stack: Vec::new(),
799 element_offset_stack: Vec::new(),
800 content_mask_stack: Vec::new(),
801 requested_autoscroll: None,
802 rendered_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
803 next_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
804 next_frame_callbacks,
805 next_hitbox_id: HitboxId::default(),
806 next_tooltip_id: TooltipId::default(),
807 tooltip_bounds: None,
808 dirty_views: FxHashSet::default(),
809 focus_handles: Arc::new(RwLock::new(SlotMap::with_key())),
810 focus_listeners: SubscriberSet::new(),
811 focus_lost_listeners: SubscriberSet::new(),
812 default_prevented: true,
813 mouse_position,
814 mouse_hit_test: HitTest::default(),
815 modifiers,
816 scale_factor,
817 bounds_observers: SubscriberSet::new(),
818 appearance,
819 appearance_observers: SubscriberSet::new(),
820 active,
821 hovered,
822 dirty,
823 needs_present,
824 last_input_timestamp,
825 refreshing: false,
826 draw_phase: DrawPhase::None,
827 activation_observers: SubscriberSet::new(),
828 focus: None,
829 focus_enabled: true,
830 pending_input: None,
831 pending_modifier: ModifierState::default(),
832 pending_input_observers: SubscriberSet::new(),
833 prompt: None,
834 })
835 }
836 fn new_focus_listener(
837 &mut self,
838 value: AnyWindowFocusListener,
839 ) -> (Subscription, impl FnOnce()) {
840 self.focus_listeners.insert((), value)
841 }
842}
843
844#[derive(Clone, Debug, Default, PartialEq, Eq)]
845pub(crate) struct DispatchEventResult {
846 pub propagate: bool,
847 pub default_prevented: bool,
848}
849
850/// Indicates which region of the window is visible. Content falling outside of this mask will not be
851/// rendered. Currently, only rectangular content masks are supported, but we give the mask its own type
852/// to leave room to support more complex shapes in the future.
853#[derive(Clone, Debug, Default, PartialEq, Eq)]
854#[repr(C)]
855pub struct ContentMask<P: Clone + Default + Debug> {
856 /// The bounds
857 pub bounds: Bounds<P>,
858}
859
860impl ContentMask<Pixels> {
861 /// Scale the content mask's pixel units by the given scaling factor.
862 pub fn scale(&self, factor: f32) -> ContentMask<ScaledPixels> {
863 ContentMask {
864 bounds: self.bounds.scale(factor),
865 }
866 }
867
868 /// Intersect the content mask with the given content mask.
869 pub fn intersect(&self, other: &Self) -> Self {
870 let bounds = self.bounds.intersect(&other.bounds);
871 ContentMask { bounds }
872 }
873}
874
875/// Provides access to application state in the context of a single window. Derefs
876/// to an [`AppContext`], so you can also pass a [`WindowContext`] to any method that takes
877/// an [`AppContext`] and call any [`AppContext`] methods.
878pub struct WindowContext<'a> {
879 pub(crate) app: &'a mut AppContext,
880 pub(crate) window: &'a mut Window,
881}
882
883impl<'a> WindowContext<'a> {
884 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window) -> Self {
885 Self { app, window }
886 }
887
888 /// Obtain a handle to the window that belongs to this context.
889 pub fn window_handle(&self) -> AnyWindowHandle {
890 self.window.handle
891 }
892
893 /// Mark the window as dirty, scheduling it to be redrawn on the next frame.
894 pub fn refresh(&mut self) {
895 if self.window.draw_phase == DrawPhase::None {
896 self.window.refreshing = true;
897 self.window.dirty.set(true);
898 }
899 }
900
901 /// Indicate that this view has changed, which will invoke any observers and also mark the window as dirty.
902 /// If this view or any of its ancestors are *cached*, notifying it will cause it or its ancestors to be redrawn.
903 pub fn notify(&mut self, view_id: EntityId) {
904 for view_id in self
905 .window
906 .rendered_frame
907 .dispatch_tree
908 .view_path(view_id)
909 .into_iter()
910 .rev()
911 {
912 if !self.window.dirty_views.insert(view_id) {
913 break;
914 }
915 }
916
917 if self.window.draw_phase == DrawPhase::None {
918 self.window.dirty.set(true);
919 self.app.push_effect(Effect::Notify { emitter: view_id });
920 }
921 }
922
923 /// Close this window.
924 pub fn remove_window(&mut self) {
925 self.window.removed = true;
926 }
927
928 /// Obtain a new [`FocusHandle`], which allows you to track and manipulate the keyboard focus
929 /// for elements rendered within this window.
930 pub fn focus_handle(&mut self) -> FocusHandle {
931 FocusHandle::new(&self.window.focus_handles)
932 }
933
934 /// Obtain the currently focused [`FocusHandle`]. If no elements are focused, returns `None`.
935 pub fn focused(&self) -> Option<FocusHandle> {
936 self.window
937 .focus
938 .and_then(|id| FocusHandle::for_id(id, &self.window.focus_handles))
939 }
940
941 /// Move focus to the element associated with the given [`FocusHandle`].
942 pub fn focus(&mut self, handle: &FocusHandle) {
943 if !self.window.focus_enabled || self.window.focus == Some(handle.id) {
944 return;
945 }
946
947 self.window.focus = Some(handle.id);
948 self.clear_pending_keystrokes();
949 self.refresh();
950 }
951
952 /// Remove focus from all elements within this context's window.
953 pub fn blur(&mut self) {
954 if !self.window.focus_enabled {
955 return;
956 }
957
958 self.window.focus = None;
959 self.refresh();
960 }
961
962 /// Blur the window and don't allow anything in it to be focused again.
963 pub fn disable_focus(&mut self) {
964 self.blur();
965 self.window.focus_enabled = false;
966 }
967
968 /// Accessor for the text system.
969 pub fn text_system(&self) -> &Arc<WindowTextSystem> {
970 &self.window.text_system
971 }
972
973 /// The current text style. Which is composed of all the style refinements provided to `with_text_style`.
974 pub fn text_style(&self) -> TextStyle {
975 let mut style = TextStyle::default();
976 for refinement in &self.window.text_style_stack {
977 style.refine(refinement);
978 }
979 style
980 }
981
982 /// Check if the platform window is maximized
983 /// On some platforms (namely Windows) this is different than the bounds being the size of the display
984 pub fn is_maximized(&self) -> bool {
985 self.window.platform_window.is_maximized()
986 }
987
988 /// request a certain window decoration (Wayland)
989 pub fn request_decorations(&self, decorations: WindowDecorations) {
990 self.window.platform_window.request_decorations(decorations);
991 }
992
993 /// Start a window resize operation (Wayland)
994 pub fn start_window_resize(&self, edge: ResizeEdge) {
995 self.window.platform_window.start_window_resize(edge);
996 }
997
998 /// Return the `WindowBounds` to indicate that how a window should be opened
999 /// after it has been closed
1000 pub fn window_bounds(&self) -> WindowBounds {
1001 self.window.platform_window.window_bounds()
1002 }
1003
1004 /// Dispatch the given action on the currently focused element.
1005 pub fn dispatch_action(&mut self, action: Box<dyn Action>) {
1006 let focus_handle = self.focused();
1007
1008 let window = self.window.handle;
1009 self.app.defer(move |cx| {
1010 window
1011 .update(cx, |_, cx| {
1012 let node_id = focus_handle
1013 .and_then(|handle| {
1014 cx.window
1015 .rendered_frame
1016 .dispatch_tree
1017 .focusable_node_id(handle.id)
1018 })
1019 .unwrap_or_else(|| cx.window.rendered_frame.dispatch_tree.root_node_id());
1020
1021 cx.dispatch_action_on_node(node_id, action.as_ref());
1022 })
1023 .log_err();
1024 })
1025 }
1026
1027 pub(crate) fn dispatch_keystroke_observers(
1028 &mut self,
1029 event: &dyn Any,
1030 action: Option<Box<dyn Action>>,
1031 ) {
1032 let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() else {
1033 return;
1034 };
1035
1036 self.keystroke_observers
1037 .clone()
1038 .retain(&(), move |callback| {
1039 (callback)(
1040 &KeystrokeEvent {
1041 keystroke: key_down_event.keystroke.clone(),
1042 action: action.as_ref().map(|action| action.boxed_clone()),
1043 },
1044 self,
1045 );
1046 true
1047 });
1048 }
1049
1050 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
1051 /// that are currently on the stack to be returned to the app.
1052 pub fn defer(&mut self, f: impl FnOnce(&mut WindowContext) + 'static) {
1053 let handle = self.window.handle;
1054 self.app.defer(move |cx| {
1055 handle.update(cx, |_, cx| f(cx)).ok();
1056 });
1057 }
1058
1059 /// Subscribe to events emitted by a model or view.
1060 /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
1061 /// 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.
1062 pub fn observe<E, T>(
1063 &mut self,
1064 entity: &E,
1065 mut on_notify: impl FnMut(E, &mut WindowContext<'_>) + 'static,
1066 ) -> Subscription
1067 where
1068 E: Entity<T>,
1069 {
1070 let entity_id = entity.entity_id();
1071 let entity = entity.downgrade();
1072 let window_handle = self.window.handle;
1073 self.app.new_observer(
1074 entity_id,
1075 Box::new(move |cx| {
1076 window_handle
1077 .update(cx, |_, cx| {
1078 if let Some(handle) = E::upgrade_from(&entity) {
1079 on_notify(handle, cx);
1080 true
1081 } else {
1082 false
1083 }
1084 })
1085 .unwrap_or(false)
1086 }),
1087 )
1088 }
1089
1090 /// Subscribe to events emitted by a model or view.
1091 /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
1092 /// 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.
1093 pub fn subscribe<Emitter, E, Evt>(
1094 &mut self,
1095 entity: &E,
1096 mut on_event: impl FnMut(E, &Evt, &mut WindowContext<'_>) + 'static,
1097 ) -> Subscription
1098 where
1099 Emitter: EventEmitter<Evt>,
1100 E: Entity<Emitter>,
1101 Evt: 'static,
1102 {
1103 let entity_id = entity.entity_id();
1104 let entity = entity.downgrade();
1105 let window_handle = self.window.handle;
1106 self.app.new_subscription(
1107 entity_id,
1108 (
1109 TypeId::of::<Evt>(),
1110 Box::new(move |event, cx| {
1111 window_handle
1112 .update(cx, |_, cx| {
1113 if let Some(handle) = E::upgrade_from(&entity) {
1114 let event = event.downcast_ref().expect("invalid event type");
1115 on_event(handle, event, cx);
1116 true
1117 } else {
1118 false
1119 }
1120 })
1121 .unwrap_or(false)
1122 }),
1123 ),
1124 )
1125 }
1126
1127 /// Register a callback to be invoked when the given Model or View is released.
1128 pub fn observe_release<E, T>(
1129 &mut self,
1130 entity: &E,
1131 mut on_release: impl FnOnce(&mut T, &mut WindowContext) + 'static,
1132 ) -> Subscription
1133 where
1134 E: Entity<T>,
1135 T: 'static,
1136 {
1137 let entity_id = entity.entity_id();
1138 let window_handle = self.window.handle;
1139 let (subscription, activate) = self.app.release_listeners.insert(
1140 entity_id,
1141 Box::new(move |entity, cx| {
1142 let entity = entity.downcast_mut().expect("invalid entity type");
1143 let _ = window_handle.update(cx, |_, cx| on_release(entity, cx));
1144 }),
1145 );
1146 activate();
1147 subscription
1148 }
1149
1150 /// Creates an [`AsyncWindowContext`], which has a static lifetime and can be held across
1151 /// await points in async code.
1152 pub fn to_async(&self) -> AsyncWindowContext {
1153 AsyncWindowContext::new(self.app.to_async(), self.window.handle)
1154 }
1155
1156 /// Schedule the given closure to be run directly after the current frame is rendered.
1157 pub fn on_next_frame(&mut self, callback: impl FnOnce(&mut WindowContext) + 'static) {
1158 RefCell::borrow_mut(&self.window.next_frame_callbacks).push(Box::new(callback));
1159 }
1160
1161 /// Schedule a frame to be drawn on the next animation frame.
1162 ///
1163 /// This is useful for elements that need to animate continuously, such as a video player or an animated GIF.
1164 /// It will cause the window to redraw on the next frame, even if no other changes have occurred.
1165 ///
1166 /// If called from within a view, it will notify that view on the next frame. Otherwise, it will refresh the entire window.
1167 pub fn request_animation_frame(&mut self) {
1168 let parent_id = self.parent_view_id();
1169 self.on_next_frame(move |cx| {
1170 if let Some(parent_id) = parent_id {
1171 cx.notify(parent_id)
1172 } else {
1173 cx.refresh()
1174 }
1175 });
1176 }
1177
1178 /// Spawn the future returned by the given closure on the application thread pool.
1179 /// The closure is provided a handle to the current window and an `AsyncWindowContext` for
1180 /// use within your future.
1181 pub fn spawn<Fut, R>(&mut self, f: impl FnOnce(AsyncWindowContext) -> Fut) -> Task<R>
1182 where
1183 R: 'static,
1184 Fut: Future<Output = R> + 'static,
1185 {
1186 self.app
1187 .spawn(|app| f(AsyncWindowContext::new(app, self.window.handle)))
1188 }
1189
1190 fn bounds_changed(&mut self) {
1191 self.window.scale_factor = self.window.platform_window.scale_factor();
1192 self.window.viewport_size = self.window.platform_window.content_size();
1193 self.window.display_id = self
1194 .window
1195 .platform_window
1196 .display()
1197 .map(|display| display.id());
1198
1199 self.refresh();
1200
1201 self.window
1202 .bounds_observers
1203 .clone()
1204 .retain(&(), |callback| callback(self));
1205 }
1206
1207 /// Returns the bounds of the current window in the global coordinate space, which could span across multiple displays.
1208 pub fn bounds(&self) -> Bounds<Pixels> {
1209 self.window.platform_window.bounds()
1210 }
1211
1212 /// Returns whether or not the window is currently fullscreen
1213 pub fn is_fullscreen(&self) -> bool {
1214 self.window.platform_window.is_fullscreen()
1215 }
1216
1217 pub(crate) fn appearance_changed(&mut self) {
1218 self.window.appearance = self.window.platform_window.appearance();
1219
1220 self.window
1221 .appearance_observers
1222 .clone()
1223 .retain(&(), |callback| callback(self));
1224 }
1225
1226 /// Returns the appearance of the current window.
1227 pub fn appearance(&self) -> WindowAppearance {
1228 self.window.appearance
1229 }
1230
1231 /// Returns the size of the drawable area within the window.
1232 pub fn viewport_size(&self) -> Size<Pixels> {
1233 self.window.viewport_size
1234 }
1235
1236 /// Returns whether this window is focused by the operating system (receiving key events).
1237 pub fn is_window_active(&self) -> bool {
1238 self.window.active.get()
1239 }
1240
1241 /// Returns whether this window is considered to be the window
1242 /// that currently owns the mouse cursor.
1243 /// On mac, this is equivalent to `is_window_active`.
1244 pub fn is_window_hovered(&self) -> bool {
1245 if cfg!(target_os = "linux") {
1246 self.window.hovered.get()
1247 } else {
1248 self.is_window_active()
1249 }
1250 }
1251
1252 /// Toggle zoom on the window.
1253 pub fn zoom_window(&self) {
1254 self.window.platform_window.zoom();
1255 }
1256
1257 /// Opens the native title bar context menu, useful when implementing client side decorations (Wayland and X11)
1258 pub fn show_window_menu(&self, position: Point<Pixels>) {
1259 self.window.platform_window.show_window_menu(position)
1260 }
1261
1262 /// Tells the compositor to take control of window movement (Wayland and X11)
1263 ///
1264 /// Events may not be received during a move operation.
1265 pub fn start_window_move(&self) {
1266 self.window.platform_window.start_window_move()
1267 }
1268
1269 /// When using client side decorations, set this to the width of the invisible decorations (Wayland and X11)
1270 pub fn set_client_inset(&self, inset: Pixels) {
1271 self.window.platform_window.set_client_inset(inset);
1272 }
1273
1274 /// Returns whether the title bar window controls need to be rendered by the application (Wayland and X11)
1275 pub fn window_decorations(&self) -> Decorations {
1276 self.window.platform_window.window_decorations()
1277 }
1278
1279 /// Returns which window controls are currently visible (Wayland)
1280 pub fn window_controls(&self) -> WindowControls {
1281 self.window.platform_window.window_controls()
1282 }
1283
1284 /// Updates the window's title at the platform level.
1285 pub fn set_window_title(&mut self, title: &str) {
1286 self.window.platform_window.set_title(title);
1287 }
1288
1289 /// Sets the application identifier.
1290 pub fn set_app_id(&mut self, app_id: &str) {
1291 self.window.platform_window.set_app_id(app_id);
1292 }
1293
1294 /// Sets the window background appearance.
1295 pub fn set_background_appearance(&self, background_appearance: WindowBackgroundAppearance) {
1296 self.window
1297 .platform_window
1298 .set_background_appearance(background_appearance);
1299 }
1300
1301 /// Mark the window as dirty at the platform level.
1302 pub fn set_window_edited(&mut self, edited: bool) {
1303 self.window.platform_window.set_edited(edited);
1304 }
1305
1306 /// Determine the display on which the window is visible.
1307 pub fn display(&self) -> Option<Rc<dyn PlatformDisplay>> {
1308 self.platform
1309 .displays()
1310 .into_iter()
1311 .find(|display| Some(display.id()) == self.window.display_id)
1312 }
1313
1314 /// Show the platform character palette.
1315 pub fn show_character_palette(&self) {
1316 self.window.platform_window.show_character_palette();
1317 }
1318
1319 /// The scale factor of the display associated with the window. For example, it could
1320 /// return 2.0 for a "retina" display, indicating that each logical pixel should actually
1321 /// be rendered as two pixels on screen.
1322 pub fn scale_factor(&self) -> f32 {
1323 self.window.scale_factor
1324 }
1325
1326 /// The size of an em for the base font of the application. Adjusting this value allows the
1327 /// UI to scale, just like zooming a web page.
1328 pub fn rem_size(&self) -> Pixels {
1329 self.window
1330 .rem_size_override_stack
1331 .last()
1332 .copied()
1333 .unwrap_or(self.window.rem_size)
1334 }
1335
1336 /// Sets the size of an em for the base font of the application. Adjusting this value allows the
1337 /// UI to scale, just like zooming a web page.
1338 pub fn set_rem_size(&mut self, rem_size: impl Into<Pixels>) {
1339 self.window.rem_size = rem_size.into();
1340 }
1341
1342 /// Executes the provided function with the specified rem size.
1343 ///
1344 /// This method must only be called as part of element drawing.
1345 pub fn with_rem_size<F, R>(&mut self, rem_size: Option<impl Into<Pixels>>, f: F) -> R
1346 where
1347 F: FnOnce(&mut Self) -> R,
1348 {
1349 debug_assert!(
1350 matches!(
1351 self.window.draw_phase,
1352 DrawPhase::Prepaint | DrawPhase::Paint
1353 ),
1354 "this method can only be called during request_layout, prepaint, or paint"
1355 );
1356
1357 if let Some(rem_size) = rem_size {
1358 self.window.rem_size_override_stack.push(rem_size.into());
1359 let result = f(self);
1360 self.window.rem_size_override_stack.pop();
1361 result
1362 } else {
1363 f(self)
1364 }
1365 }
1366
1367 /// The line height associated with the current text style.
1368 pub fn line_height(&self) -> Pixels {
1369 let rem_size = self.rem_size();
1370 let text_style = self.text_style();
1371 text_style
1372 .line_height
1373 .to_pixels(text_style.font_size, rem_size)
1374 }
1375
1376 /// Call to prevent the default action of an event. Currently only used to prevent
1377 /// parent elements from becoming focused on mouse down.
1378 pub fn prevent_default(&mut self) {
1379 self.window.default_prevented = true;
1380 }
1381
1382 /// Obtain whether default has been prevented for the event currently being dispatched.
1383 pub fn default_prevented(&self) -> bool {
1384 self.window.default_prevented
1385 }
1386
1387 /// Determine whether the given action is available along the dispatch path to the currently focused element.
1388 pub fn is_action_available(&self, action: &dyn Action) -> bool {
1389 let target = self
1390 .focused()
1391 .and_then(|focused_handle| {
1392 self.window
1393 .rendered_frame
1394 .dispatch_tree
1395 .focusable_node_id(focused_handle.id)
1396 })
1397 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
1398 self.window
1399 .rendered_frame
1400 .dispatch_tree
1401 .is_action_available(action, target)
1402 }
1403
1404 /// The position of the mouse relative to the window.
1405 pub fn mouse_position(&self) -> Point<Pixels> {
1406 self.window.mouse_position
1407 }
1408
1409 /// The current state of the keyboard's modifiers
1410 pub fn modifiers(&self) -> Modifiers {
1411 self.window.modifiers
1412 }
1413
1414 fn complete_frame(&self) {
1415 self.window.platform_window.completed_frame();
1416 }
1417
1418 /// Produces a new frame and assigns it to `rendered_frame`. To actually show
1419 /// the contents of the new [Scene], use [present].
1420 #[profiling::function]
1421 pub fn draw(&mut self) {
1422 self.window.dirty.set(false);
1423 self.window.requested_autoscroll = None;
1424
1425 // Restore the previously-used input handler.
1426 if let Some(input_handler) = self.window.platform_window.take_input_handler() {
1427 self.window
1428 .rendered_frame
1429 .input_handlers
1430 .push(Some(input_handler));
1431 }
1432
1433 self.draw_roots();
1434 self.window.dirty_views.clear();
1435 self.window.next_frame.window_active = self.window.active.get();
1436
1437 // Register requested input handler with the platform window.
1438 if let Some(input_handler) = self.window.next_frame.input_handlers.pop() {
1439 self.window
1440 .platform_window
1441 .set_input_handler(input_handler.unwrap());
1442 }
1443
1444 self.window.layout_engine.as_mut().unwrap().clear();
1445 self.text_system().finish_frame();
1446 self.window
1447 .next_frame
1448 .finish(&mut self.window.rendered_frame);
1449 ELEMENT_ARENA.with_borrow_mut(|element_arena| {
1450 let percentage = (element_arena.len() as f32 / element_arena.capacity() as f32) * 100.;
1451 if percentage >= 80. {
1452 log::warn!("elevated element arena occupation: {}.", percentage);
1453 }
1454 element_arena.clear();
1455 });
1456
1457 self.window.draw_phase = DrawPhase::Focus;
1458 let previous_focus_path = self.window.rendered_frame.focus_path();
1459 let previous_window_active = self.window.rendered_frame.window_active;
1460 mem::swap(&mut self.window.rendered_frame, &mut self.window.next_frame);
1461 self.window.next_frame.clear();
1462 let current_focus_path = self.window.rendered_frame.focus_path();
1463 let current_window_active = self.window.rendered_frame.window_active;
1464
1465 if previous_focus_path != current_focus_path
1466 || previous_window_active != current_window_active
1467 {
1468 if !previous_focus_path.is_empty() && current_focus_path.is_empty() {
1469 self.window
1470 .focus_lost_listeners
1471 .clone()
1472 .retain(&(), |listener| listener(self));
1473 }
1474
1475 let event = WindowFocusEvent {
1476 previous_focus_path: if previous_window_active {
1477 previous_focus_path
1478 } else {
1479 Default::default()
1480 },
1481 current_focus_path: if current_window_active {
1482 current_focus_path
1483 } else {
1484 Default::default()
1485 },
1486 };
1487 self.window
1488 .focus_listeners
1489 .clone()
1490 .retain(&(), |listener| listener(&event, self));
1491 }
1492
1493 self.reset_cursor_style();
1494 self.window.refreshing = false;
1495 self.window.draw_phase = DrawPhase::None;
1496 self.window.needs_present.set(true);
1497 }
1498
1499 #[profiling::function]
1500 fn present(&self) {
1501 self.window
1502 .platform_window
1503 .draw(&self.window.rendered_frame.scene);
1504 self.window.needs_present.set(false);
1505 profiling::finish_frame!();
1506 }
1507
1508 fn draw_roots(&mut self) {
1509 self.window.draw_phase = DrawPhase::Prepaint;
1510 self.window.tooltip_bounds.take();
1511
1512 // Layout all root elements.
1513 let mut root_element = self.window.root_view.as_ref().unwrap().clone().into_any();
1514 root_element.prepaint_as_root(Point::default(), self.window.viewport_size.into(), self);
1515
1516 let mut sorted_deferred_draws =
1517 (0..self.window.next_frame.deferred_draws.len()).collect::<SmallVec<[_; 8]>>();
1518 sorted_deferred_draws.sort_by_key(|ix| self.window.next_frame.deferred_draws[*ix].priority);
1519 self.prepaint_deferred_draws(&sorted_deferred_draws);
1520
1521 let mut prompt_element = None;
1522 let mut active_drag_element = None;
1523 let mut tooltip_element = None;
1524 if let Some(prompt) = self.window.prompt.take() {
1525 let mut element = prompt.view.any_view().into_any();
1526 element.prepaint_as_root(Point::default(), self.window.viewport_size.into(), self);
1527 prompt_element = Some(element);
1528 self.window.prompt = Some(prompt);
1529 } else if let Some(active_drag) = self.app.active_drag.take() {
1530 let mut element = active_drag.view.clone().into_any();
1531 let offset = self.mouse_position() - active_drag.cursor_offset;
1532 element.prepaint_as_root(offset, AvailableSpace::min_size(), self);
1533 active_drag_element = Some(element);
1534 self.app.active_drag = Some(active_drag);
1535 } else {
1536 tooltip_element = self.prepaint_tooltip();
1537 }
1538
1539 self.window.mouse_hit_test = self.window.next_frame.hit_test(self.window.mouse_position);
1540
1541 // Now actually paint the elements.
1542 self.window.draw_phase = DrawPhase::Paint;
1543 root_element.paint(self);
1544
1545 self.paint_deferred_draws(&sorted_deferred_draws);
1546
1547 if let Some(mut prompt_element) = prompt_element {
1548 prompt_element.paint(self);
1549 } else if let Some(mut drag_element) = active_drag_element {
1550 drag_element.paint(self);
1551 } else if let Some(mut tooltip_element) = tooltip_element {
1552 tooltip_element.paint(self);
1553 }
1554 }
1555
1556 fn prepaint_tooltip(&mut self) -> Option<AnyElement> {
1557 let tooltip_request = self.window.next_frame.tooltip_requests.last().cloned()?;
1558 let tooltip_request = tooltip_request.unwrap();
1559 let mut element = tooltip_request.tooltip.view.clone().into_any();
1560 let mouse_position = tooltip_request.tooltip.mouse_position;
1561 let tooltip_size = element.layout_as_root(AvailableSpace::min_size(), self);
1562
1563 let mut tooltip_bounds = Bounds::new(mouse_position + point(px(1.), px(1.)), tooltip_size);
1564 let window_bounds = Bounds {
1565 origin: Point::default(),
1566 size: self.viewport_size(),
1567 };
1568
1569 if tooltip_bounds.right() > window_bounds.right() {
1570 let new_x = mouse_position.x - tooltip_bounds.size.width - px(1.);
1571 if new_x >= Pixels::ZERO {
1572 tooltip_bounds.origin.x = new_x;
1573 } else {
1574 tooltip_bounds.origin.x = cmp::max(
1575 Pixels::ZERO,
1576 tooltip_bounds.origin.x - tooltip_bounds.right() - window_bounds.right(),
1577 );
1578 }
1579 }
1580
1581 if tooltip_bounds.bottom() > window_bounds.bottom() {
1582 let new_y = mouse_position.y - tooltip_bounds.size.height - px(1.);
1583 if new_y >= Pixels::ZERO {
1584 tooltip_bounds.origin.y = new_y;
1585 } else {
1586 tooltip_bounds.origin.y = cmp::max(
1587 Pixels::ZERO,
1588 tooltip_bounds.origin.y - tooltip_bounds.bottom() - window_bounds.bottom(),
1589 );
1590 }
1591 }
1592
1593 self.with_absolute_element_offset(tooltip_bounds.origin, |cx| element.prepaint(cx));
1594
1595 self.window.tooltip_bounds = Some(TooltipBounds {
1596 id: tooltip_request.id,
1597 bounds: tooltip_bounds,
1598 });
1599 Some(element)
1600 }
1601
1602 fn prepaint_deferred_draws(&mut self, deferred_draw_indices: &[usize]) {
1603 assert_eq!(self.window.element_id_stack.len(), 0);
1604
1605 let mut deferred_draws = mem::take(&mut self.window.next_frame.deferred_draws);
1606 for deferred_draw_ix in deferred_draw_indices {
1607 let deferred_draw = &mut deferred_draws[*deferred_draw_ix];
1608 self.window
1609 .element_id_stack
1610 .clone_from(&deferred_draw.element_id_stack);
1611 self.window
1612 .text_style_stack
1613 .clone_from(&deferred_draw.text_style_stack);
1614 self.window
1615 .next_frame
1616 .dispatch_tree
1617 .set_active_node(deferred_draw.parent_node);
1618
1619 let prepaint_start = self.prepaint_index();
1620 if let Some(element) = deferred_draw.element.as_mut() {
1621 self.with_absolute_element_offset(deferred_draw.absolute_offset, |cx| {
1622 element.prepaint(cx)
1623 });
1624 } else {
1625 self.reuse_prepaint(deferred_draw.prepaint_range.clone());
1626 }
1627 let prepaint_end = self.prepaint_index();
1628 deferred_draw.prepaint_range = prepaint_start..prepaint_end;
1629 }
1630 assert_eq!(
1631 self.window.next_frame.deferred_draws.len(),
1632 0,
1633 "cannot call defer_draw during deferred drawing"
1634 );
1635 self.window.next_frame.deferred_draws = deferred_draws;
1636 self.window.element_id_stack.clear();
1637 self.window.text_style_stack.clear();
1638 }
1639
1640 fn paint_deferred_draws(&mut self, deferred_draw_indices: &[usize]) {
1641 assert_eq!(self.window.element_id_stack.len(), 0);
1642
1643 let mut deferred_draws = mem::take(&mut self.window.next_frame.deferred_draws);
1644 for deferred_draw_ix in deferred_draw_indices {
1645 let mut deferred_draw = &mut deferred_draws[*deferred_draw_ix];
1646 self.window
1647 .element_id_stack
1648 .clone_from(&deferred_draw.element_id_stack);
1649 self.window
1650 .next_frame
1651 .dispatch_tree
1652 .set_active_node(deferred_draw.parent_node);
1653
1654 let paint_start = self.paint_index();
1655 if let Some(element) = deferred_draw.element.as_mut() {
1656 element.paint(self);
1657 } else {
1658 self.reuse_paint(deferred_draw.paint_range.clone());
1659 }
1660 let paint_end = self.paint_index();
1661 deferred_draw.paint_range = paint_start..paint_end;
1662 }
1663 self.window.next_frame.deferred_draws = deferred_draws;
1664 self.window.element_id_stack.clear();
1665 }
1666
1667 pub(crate) fn prepaint_index(&self) -> PrepaintStateIndex {
1668 PrepaintStateIndex {
1669 hitboxes_index: self.window.next_frame.hitboxes.len(),
1670 tooltips_index: self.window.next_frame.tooltip_requests.len(),
1671 deferred_draws_index: self.window.next_frame.deferred_draws.len(),
1672 dispatch_tree_index: self.window.next_frame.dispatch_tree.len(),
1673 accessed_element_states_index: self.window.next_frame.accessed_element_states.len(),
1674 line_layout_index: self.window.text_system.layout_index(),
1675 }
1676 }
1677
1678 pub(crate) fn reuse_prepaint(&mut self, range: Range<PrepaintStateIndex>) {
1679 let window = &mut self.window;
1680 window.next_frame.hitboxes.extend(
1681 window.rendered_frame.hitboxes[range.start.hitboxes_index..range.end.hitboxes_index]
1682 .iter()
1683 .cloned(),
1684 );
1685 window.next_frame.tooltip_requests.extend(
1686 window.rendered_frame.tooltip_requests
1687 [range.start.tooltips_index..range.end.tooltips_index]
1688 .iter_mut()
1689 .map(|request| request.take()),
1690 );
1691 window.next_frame.accessed_element_states.extend(
1692 window.rendered_frame.accessed_element_states[range.start.accessed_element_states_index
1693 ..range.end.accessed_element_states_index]
1694 .iter()
1695 .map(|(id, type_id)| (GlobalElementId(id.0.clone()), *type_id)),
1696 );
1697 window
1698 .text_system
1699 .reuse_layouts(range.start.line_layout_index..range.end.line_layout_index);
1700
1701 let reused_subtree = window.next_frame.dispatch_tree.reuse_subtree(
1702 range.start.dispatch_tree_index..range.end.dispatch_tree_index,
1703 &mut window.rendered_frame.dispatch_tree,
1704 window.focus,
1705 );
1706
1707 if reused_subtree.contains_focus() {
1708 window.next_frame.focus = window.focus;
1709 }
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 identifiers 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 frame_index: usize,
2623 grayscale: bool,
2624 ) -> Result<()> {
2625 debug_assert_eq!(
2626 self.window.draw_phase,
2627 DrawPhase::Paint,
2628 "this method can only be called during paint"
2629 );
2630
2631 let scale_factor = self.scale_factor();
2632 let bounds = bounds.scale(scale_factor);
2633 let params = RenderImageParams {
2634 image_id: data.id,
2635 frame_index,
2636 };
2637
2638 let tile = self
2639 .window
2640 .sprite_atlas
2641 .get_or_insert_with(¶ms.clone().into(), &mut || {
2642 Ok(Some((
2643 data.size(frame_index),
2644 Cow::Borrowed(data.as_bytes(frame_index)),
2645 )))
2646 })?
2647 .expect("Callback above only returns Some");
2648 let content_mask = self.content_mask().scale(scale_factor);
2649 let corner_radii = corner_radii.scale(scale_factor);
2650
2651 self.window
2652 .next_frame
2653 .scene
2654 .insert_primitive(PolychromeSprite {
2655 order: 0,
2656 grayscale,
2657 bounds,
2658 content_mask,
2659 corner_radii,
2660 tile,
2661 });
2662 Ok(())
2663 }
2664
2665 /// Paint a surface into the scene for the next frame at the current z-index.
2666 ///
2667 /// This method should only be called as part of the paint phase of element drawing.
2668 #[cfg(target_os = "macos")]
2669 pub fn paint_surface(&mut self, bounds: Bounds<Pixels>, image_buffer: CVImageBuffer) {
2670 debug_assert_eq!(
2671 self.window.draw_phase,
2672 DrawPhase::Paint,
2673 "this method can only be called during paint"
2674 );
2675
2676 let scale_factor = self.scale_factor();
2677 let bounds = bounds.scale(scale_factor);
2678 let content_mask = self.content_mask().scale(scale_factor);
2679 self.window
2680 .next_frame
2681 .scene
2682 .insert_primitive(crate::Surface {
2683 order: 0,
2684 bounds,
2685 content_mask,
2686 image_buffer,
2687 });
2688 }
2689
2690 #[must_use]
2691 /// Add a node to the layout tree for the current frame. Takes the `Style` of the element for which
2692 /// layout is being requested, along with the layout ids of any children. This method is called during
2693 /// calls to the [`Element::request_layout`] trait method and enables any element to participate in layout.
2694 ///
2695 /// This method should only be called as part of the request_layout or prepaint phase of element drawing.
2696 pub fn request_layout(
2697 &mut self,
2698 style: Style,
2699 children: impl IntoIterator<Item = LayoutId>,
2700 ) -> LayoutId {
2701 debug_assert_eq!(
2702 self.window.draw_phase,
2703 DrawPhase::Prepaint,
2704 "this method can only be called during request_layout, or prepaint"
2705 );
2706
2707 self.app.layout_id_buffer.clear();
2708 self.app.layout_id_buffer.extend(children);
2709 let rem_size = self.rem_size();
2710
2711 self.window.layout_engine.as_mut().unwrap().request_layout(
2712 style,
2713 rem_size,
2714 &self.app.layout_id_buffer,
2715 )
2716 }
2717
2718 /// Add a node to the layout tree for the current frame. Instead of taking a `Style` and children,
2719 /// this variant takes a function that is invoked during layout so you can use arbitrary logic to
2720 /// determine the element's size. One place this is used internally is when measuring text.
2721 ///
2722 /// The given closure is invoked at layout time with the known dimensions and available space and
2723 /// returns a `Size`.
2724 ///
2725 /// This method should only be called as part of the request_layout or prepaint phase of element drawing.
2726 pub fn request_measured_layout<
2727 F: FnMut(Size<Option<Pixels>>, Size<AvailableSpace>, &mut WindowContext) -> Size<Pixels>
2728 + 'static,
2729 >(
2730 &mut self,
2731 style: Style,
2732 measure: F,
2733 ) -> LayoutId {
2734 debug_assert_eq!(
2735 self.window.draw_phase,
2736 DrawPhase::Prepaint,
2737 "this method can only be called during request_layout, or prepaint"
2738 );
2739
2740 let rem_size = self.rem_size();
2741 self.window
2742 .layout_engine
2743 .as_mut()
2744 .unwrap()
2745 .request_measured_layout(style, rem_size, measure)
2746 }
2747
2748 /// Compute the layout for the given id within the given available space.
2749 /// This method is called for its side effect, typically by the framework prior to painting.
2750 /// After calling it, you can request the bounds of the given layout node id or any descendant.
2751 ///
2752 /// This method should only be called as part of the prepaint phase of element drawing.
2753 pub fn compute_layout(&mut self, layout_id: LayoutId, available_space: Size<AvailableSpace>) {
2754 debug_assert_eq!(
2755 self.window.draw_phase,
2756 DrawPhase::Prepaint,
2757 "this method can only be called during request_layout, or prepaint"
2758 );
2759
2760 let mut layout_engine = self.window.layout_engine.take().unwrap();
2761 layout_engine.compute_layout(layout_id, available_space, self);
2762 self.window.layout_engine = Some(layout_engine);
2763 }
2764
2765 /// Obtain the bounds computed for the given LayoutId relative to the window. This method will usually be invoked by
2766 /// GPUI itself automatically in order to pass your element its `Bounds` automatically.
2767 ///
2768 /// This method should only be called as part of element drawing.
2769 pub fn layout_bounds(&mut self, layout_id: LayoutId) -> Bounds<Pixels> {
2770 debug_assert_eq!(
2771 self.window.draw_phase,
2772 DrawPhase::Prepaint,
2773 "this method can only be called during request_layout, prepaint, or paint"
2774 );
2775
2776 let mut bounds = self
2777 .window
2778 .layout_engine
2779 .as_mut()
2780 .unwrap()
2781 .layout_bounds(layout_id)
2782 .map(Into::into);
2783 bounds.origin += self.element_offset();
2784 bounds
2785 }
2786
2787 /// This method should be called during `prepaint`. You can use
2788 /// the returned [Hitbox] during `paint` or in an event handler
2789 /// to determine whether the inserted hitbox was the topmost.
2790 ///
2791 /// This method should only be called as part of the prepaint phase of element drawing.
2792 pub fn insert_hitbox(&mut self, bounds: Bounds<Pixels>, opaque: bool) -> Hitbox {
2793 debug_assert_eq!(
2794 self.window.draw_phase,
2795 DrawPhase::Prepaint,
2796 "this method can only be called during prepaint"
2797 );
2798
2799 let content_mask = self.content_mask();
2800 let window = &mut self.window;
2801 let id = window.next_hitbox_id;
2802 window.next_hitbox_id.0 += 1;
2803 let hitbox = Hitbox {
2804 id,
2805 bounds,
2806 content_mask,
2807 opaque,
2808 };
2809 window.next_frame.hitboxes.push(hitbox.clone());
2810 hitbox
2811 }
2812
2813 /// Sets the key context for the current element. This context will be used to translate
2814 /// keybindings into actions.
2815 ///
2816 /// This method should only be called as part of the paint phase of element drawing.
2817 pub fn set_key_context(&mut self, context: KeyContext) {
2818 debug_assert_eq!(
2819 self.window.draw_phase,
2820 DrawPhase::Paint,
2821 "this method can only be called during paint"
2822 );
2823 self.window
2824 .next_frame
2825 .dispatch_tree
2826 .set_key_context(context);
2827 }
2828
2829 /// Sets the focus handle for the current element. This handle will be used to manage focus state
2830 /// and keyboard event dispatch for the element.
2831 ///
2832 /// This method should only be called as part of the prepaint phase of element drawing.
2833 pub fn set_focus_handle(&mut self, focus_handle: &FocusHandle) {
2834 debug_assert_eq!(
2835 self.window.draw_phase,
2836 DrawPhase::Prepaint,
2837 "this method can only be called during prepaint"
2838 );
2839 if focus_handle.is_focused(self) {
2840 self.window.next_frame.focus = Some(focus_handle.id);
2841 }
2842 self.window
2843 .next_frame
2844 .dispatch_tree
2845 .set_focus_id(focus_handle.id);
2846 }
2847
2848 /// Sets the view id for the current element, which will be used to manage view caching.
2849 ///
2850 /// This method should only be called as part of element prepaint. We plan on removing this
2851 /// method eventually when we solve some issues that require us to construct editor elements
2852 /// directly instead of always using editors via views.
2853 pub fn set_view_id(&mut self, view_id: EntityId) {
2854 debug_assert_eq!(
2855 self.window.draw_phase,
2856 DrawPhase::Prepaint,
2857 "this method can only be called during prepaint"
2858 );
2859 self.window.next_frame.dispatch_tree.set_view_id(view_id);
2860 }
2861
2862 /// Get the last view id for the current element
2863 pub fn parent_view_id(&mut self) -> Option<EntityId> {
2864 self.window.next_frame.dispatch_tree.parent_view_id()
2865 }
2866
2867 /// Sets an input handler, such as [`ElementInputHandler`][element_input_handler], which interfaces with the
2868 /// platform to receive textual input with proper integration with concerns such
2869 /// as IME interactions. This handler will be active for the upcoming frame until the following frame is
2870 /// rendered.
2871 ///
2872 /// This method should only be called as part of the paint phase of element drawing.
2873 ///
2874 /// [element_input_handler]: crate::ElementInputHandler
2875 pub fn handle_input(&mut self, focus_handle: &FocusHandle, input_handler: impl InputHandler) {
2876 debug_assert_eq!(
2877 self.window.draw_phase,
2878 DrawPhase::Paint,
2879 "this method can only be called during paint"
2880 );
2881
2882 if focus_handle.is_focused(self) {
2883 let cx = self.to_async();
2884 self.window
2885 .next_frame
2886 .input_handlers
2887 .push(Some(PlatformInputHandler::new(cx, Box::new(input_handler))));
2888 }
2889 }
2890
2891 /// Register a mouse event listener on the window for the next frame. The type of event
2892 /// is determined by the first parameter of the given listener. When the next frame is rendered
2893 /// the listener will be cleared.
2894 ///
2895 /// This method should only be called as part of the paint phase of element drawing.
2896 pub fn on_mouse_event<Event: MouseEvent>(
2897 &mut self,
2898 mut handler: impl FnMut(&Event, DispatchPhase, &mut WindowContext) + 'static,
2899 ) {
2900 debug_assert_eq!(
2901 self.window.draw_phase,
2902 DrawPhase::Paint,
2903 "this method can only be called during paint"
2904 );
2905
2906 self.window.next_frame.mouse_listeners.push(Some(Box::new(
2907 move |event: &dyn Any, phase: DispatchPhase, cx: &mut WindowContext<'_>| {
2908 if let Some(event) = event.downcast_ref() {
2909 handler(event, phase, cx)
2910 }
2911 },
2912 )));
2913 }
2914
2915 /// Register a key event listener on the window for the next frame. The type of event
2916 /// is determined by the first parameter of the given listener. When the next frame is rendered
2917 /// the listener will be cleared.
2918 ///
2919 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
2920 /// a specific need to register a global listener.
2921 ///
2922 /// This method should only be called as part of the paint phase of element drawing.
2923 pub fn on_key_event<Event: KeyEvent>(
2924 &mut self,
2925 listener: impl Fn(&Event, DispatchPhase, &mut WindowContext) + 'static,
2926 ) {
2927 debug_assert_eq!(
2928 self.window.draw_phase,
2929 DrawPhase::Paint,
2930 "this method can only be called during paint"
2931 );
2932
2933 self.window.next_frame.dispatch_tree.on_key_event(Rc::new(
2934 move |event: &dyn Any, phase, cx: &mut WindowContext<'_>| {
2935 if let Some(event) = event.downcast_ref::<Event>() {
2936 listener(event, phase, cx)
2937 }
2938 },
2939 ));
2940 }
2941
2942 /// Register a modifiers changed event listener on the window for the next frame.
2943 ///
2944 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
2945 /// a specific need to register a global listener.
2946 ///
2947 /// This method should only be called as part of the paint phase of element drawing.
2948 pub fn on_modifiers_changed(
2949 &mut self,
2950 listener: impl Fn(&ModifiersChangedEvent, &mut WindowContext) + 'static,
2951 ) {
2952 debug_assert_eq!(
2953 self.window.draw_phase,
2954 DrawPhase::Paint,
2955 "this method can only be called during paint"
2956 );
2957
2958 self.window
2959 .next_frame
2960 .dispatch_tree
2961 .on_modifiers_changed(Rc::new(
2962 move |event: &ModifiersChangedEvent, cx: &mut WindowContext<'_>| {
2963 listener(event, cx)
2964 },
2965 ));
2966 }
2967
2968 /// Register a listener to be called when the given focus handle or one of its descendants receives focus.
2969 /// This does not fire if the given focus handle - or one of its descendants - was previously focused.
2970 /// Returns a subscription and persists until the subscription is dropped.
2971 pub fn on_focus_in(
2972 &mut self,
2973 handle: &FocusHandle,
2974 mut listener: impl FnMut(&mut WindowContext) + 'static,
2975 ) -> Subscription {
2976 let focus_id = handle.id;
2977 let (subscription, activate) =
2978 self.window.new_focus_listener(Box::new(move |event, cx| {
2979 if event.is_focus_in(focus_id) {
2980 listener(cx);
2981 }
2982 true
2983 }));
2984 self.app.defer(move |_| activate());
2985 subscription
2986 }
2987
2988 /// Register a listener to be called when the given focus handle or one of its descendants loses focus.
2989 /// Returns a subscription and persists until the subscription is dropped.
2990 pub fn on_focus_out(
2991 &mut self,
2992 handle: &FocusHandle,
2993 mut listener: impl FnMut(FocusOutEvent, &mut WindowContext) + 'static,
2994 ) -> Subscription {
2995 let focus_id = handle.id;
2996 let (subscription, activate) =
2997 self.window.new_focus_listener(Box::new(move |event, cx| {
2998 if let Some(blurred_id) = event.previous_focus_path.last().copied() {
2999 if event.is_focus_out(focus_id) {
3000 let event = FocusOutEvent {
3001 blurred: WeakFocusHandle {
3002 id: blurred_id,
3003 handles: Arc::downgrade(&cx.window.focus_handles),
3004 },
3005 };
3006 listener(event, cx)
3007 }
3008 }
3009 true
3010 }));
3011 self.app.defer(move |_| activate());
3012 subscription
3013 }
3014
3015 fn reset_cursor_style(&self) {
3016 // Set the cursor only if we're the active window.
3017 if self.is_window_hovered() {
3018 let style = self
3019 .window
3020 .rendered_frame
3021 .cursor_styles
3022 .iter()
3023 .rev()
3024 .find(|request| request.hitbox_id.is_hovered(self))
3025 .map(|request| request.style)
3026 .unwrap_or(CursorStyle::Arrow);
3027 self.platform.set_cursor_style(style);
3028 }
3029 }
3030
3031 /// Dispatch a given keystroke as though the user had typed it.
3032 /// You can create a keystroke with Keystroke::parse("").
3033 pub fn dispatch_keystroke(&mut self, keystroke: Keystroke) -> bool {
3034 let keystroke = keystroke.with_simulated_ime();
3035 let result = self.dispatch_event(PlatformInput::KeyDown(KeyDownEvent {
3036 keystroke: keystroke.clone(),
3037 is_held: false,
3038 }));
3039 if !result.propagate {
3040 return true;
3041 }
3042
3043 if let Some(input) = keystroke.ime_key {
3044 if let Some(mut input_handler) = self.window.platform_window.take_input_handler() {
3045 input_handler.dispatch_input(&input, self);
3046 self.window.platform_window.set_input_handler(input_handler);
3047 return true;
3048 }
3049 }
3050
3051 false
3052 }
3053
3054 /// Represent this action as a key binding string, to display in the UI.
3055 pub fn keystroke_text_for(&self, action: &dyn Action) -> String {
3056 self.bindings_for_action(action)
3057 .into_iter()
3058 .next()
3059 .map(|binding| {
3060 binding
3061 .keystrokes()
3062 .iter()
3063 .map(ToString::to_string)
3064 .collect::<Vec<_>>()
3065 .join(" ")
3066 })
3067 .unwrap_or_else(|| action.name().to_string())
3068 }
3069
3070 /// Dispatch a mouse or keyboard event on the window.
3071 #[profiling::function]
3072 pub fn dispatch_event(&mut self, event: PlatformInput) -> DispatchEventResult {
3073 self.window.last_input_timestamp.set(Instant::now());
3074 // Handlers may set this to false by calling `stop_propagation`.
3075 self.app.propagate_event = true;
3076 // Handlers may set this to true by calling `prevent_default`.
3077 self.window.default_prevented = false;
3078
3079 let event = match event {
3080 // Track the mouse position with our own state, since accessing the platform
3081 // API for the mouse position can only occur on the main thread.
3082 PlatformInput::MouseMove(mouse_move) => {
3083 self.window.mouse_position = mouse_move.position;
3084 self.window.modifiers = mouse_move.modifiers;
3085 PlatformInput::MouseMove(mouse_move)
3086 }
3087 PlatformInput::MouseDown(mouse_down) => {
3088 self.window.mouse_position = mouse_down.position;
3089 self.window.modifiers = mouse_down.modifiers;
3090 PlatformInput::MouseDown(mouse_down)
3091 }
3092 PlatformInput::MouseUp(mouse_up) => {
3093 self.window.mouse_position = mouse_up.position;
3094 self.window.modifiers = mouse_up.modifiers;
3095 PlatformInput::MouseUp(mouse_up)
3096 }
3097 PlatformInput::MouseExited(mouse_exited) => {
3098 self.window.modifiers = mouse_exited.modifiers;
3099 PlatformInput::MouseExited(mouse_exited)
3100 }
3101 PlatformInput::ModifiersChanged(modifiers_changed) => {
3102 self.window.modifiers = modifiers_changed.modifiers;
3103 PlatformInput::ModifiersChanged(modifiers_changed)
3104 }
3105 PlatformInput::ScrollWheel(scroll_wheel) => {
3106 self.window.mouse_position = scroll_wheel.position;
3107 self.window.modifiers = scroll_wheel.modifiers;
3108 PlatformInput::ScrollWheel(scroll_wheel)
3109 }
3110 // Translate dragging and dropping of external files from the operating system
3111 // to internal drag and drop events.
3112 PlatformInput::FileDrop(file_drop) => match file_drop {
3113 FileDropEvent::Entered { position, paths } => {
3114 self.window.mouse_position = position;
3115 if self.active_drag.is_none() {
3116 self.active_drag = Some(AnyDrag {
3117 value: Box::new(paths.clone()),
3118 view: self.new_view(|_| paths).into(),
3119 cursor_offset: position,
3120 });
3121 }
3122 PlatformInput::MouseMove(MouseMoveEvent {
3123 position,
3124 pressed_button: Some(MouseButton::Left),
3125 modifiers: Modifiers::default(),
3126 })
3127 }
3128 FileDropEvent::Pending { position } => {
3129 self.window.mouse_position = position;
3130 PlatformInput::MouseMove(MouseMoveEvent {
3131 position,
3132 pressed_button: Some(MouseButton::Left),
3133 modifiers: Modifiers::default(),
3134 })
3135 }
3136 FileDropEvent::Submit { position } => {
3137 self.activate(true);
3138 self.window.mouse_position = position;
3139 PlatformInput::MouseUp(MouseUpEvent {
3140 button: MouseButton::Left,
3141 position,
3142 modifiers: Modifiers::default(),
3143 click_count: 1,
3144 })
3145 }
3146 FileDropEvent::Exited => {
3147 self.active_drag.take();
3148 PlatformInput::FileDrop(FileDropEvent::Exited)
3149 }
3150 },
3151 PlatformInput::KeyDown(_) | PlatformInput::KeyUp(_) => event,
3152 };
3153
3154 if let Some(any_mouse_event) = event.mouse_event() {
3155 self.dispatch_mouse_event(any_mouse_event);
3156 } else if let Some(any_key_event) = event.keyboard_event() {
3157 self.dispatch_key_event(any_key_event);
3158 }
3159
3160 DispatchEventResult {
3161 propagate: self.app.propagate_event,
3162 default_prevented: self.window.default_prevented,
3163 }
3164 }
3165
3166 fn dispatch_mouse_event(&mut self, event: &dyn Any) {
3167 let hit_test = self.window.rendered_frame.hit_test(self.mouse_position());
3168 if hit_test != self.window.mouse_hit_test {
3169 self.window.mouse_hit_test = hit_test;
3170 self.reset_cursor_style();
3171 }
3172
3173 let mut mouse_listeners = mem::take(&mut self.window.rendered_frame.mouse_listeners);
3174
3175 // Capture phase, events bubble from back to front. Handlers for this phase are used for
3176 // special purposes, such as detecting events outside of a given Bounds.
3177 for listener in &mut mouse_listeners {
3178 let listener = listener.as_mut().unwrap();
3179 listener(event, DispatchPhase::Capture, self);
3180 if !self.app.propagate_event {
3181 break;
3182 }
3183 }
3184
3185 // Bubble phase, where most normal handlers do their work.
3186 if self.app.propagate_event {
3187 for listener in mouse_listeners.iter_mut().rev() {
3188 let listener = listener.as_mut().unwrap();
3189 listener(event, DispatchPhase::Bubble, self);
3190 if !self.app.propagate_event {
3191 break;
3192 }
3193 }
3194 }
3195
3196 self.window.rendered_frame.mouse_listeners = mouse_listeners;
3197
3198 if self.has_active_drag() {
3199 if event.is::<MouseMoveEvent>() {
3200 // If this was a mouse move event, redraw the window so that the
3201 // active drag can follow the mouse cursor.
3202 self.refresh();
3203 } else if event.is::<MouseUpEvent>() {
3204 // If this was a mouse up event, cancel the active drag and redraw
3205 // the window.
3206 self.active_drag = None;
3207 self.refresh();
3208 }
3209 }
3210 }
3211
3212 fn dispatch_key_event(&mut self, event: &dyn Any) {
3213 if self.window.dirty.get() {
3214 self.draw();
3215 }
3216
3217 let node_id = self
3218 .window
3219 .focus
3220 .and_then(|focus_id| {
3221 self.window
3222 .rendered_frame
3223 .dispatch_tree
3224 .focusable_node_id(focus_id)
3225 })
3226 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3227
3228 let dispatch_path = self
3229 .window
3230 .rendered_frame
3231 .dispatch_tree
3232 .dispatch_path(node_id);
3233
3234 let mut keystroke: Option<Keystroke> = None;
3235
3236 if let Some(event) = event.downcast_ref::<ModifiersChangedEvent>() {
3237 if event.modifiers.number_of_modifiers() == 0
3238 && self.window.pending_modifier.modifiers.number_of_modifiers() == 1
3239 && !self.window.pending_modifier.saw_keystroke
3240 {
3241 if event.modifiers.number_of_modifiers() == 0 {
3242 let key = match self.window.pending_modifier.modifiers {
3243 modifiers if modifiers.shift => Some("shift"),
3244 modifiers if modifiers.control => Some("control"),
3245 modifiers if modifiers.alt => Some("alt"),
3246 modifiers if modifiers.platform => Some("platform"),
3247 modifiers if modifiers.function => Some("function"),
3248 _ => None,
3249 };
3250 if let Some(key) = key {
3251 keystroke = Some(Keystroke {
3252 key: key.to_string(),
3253 ime_key: None,
3254 modifiers: Modifiers::default(),
3255 });
3256 }
3257 }
3258 }
3259 if self.window.pending_modifier.modifiers.number_of_modifiers() == 0
3260 && event.modifiers.number_of_modifiers() == 1
3261 {
3262 self.window.pending_modifier.saw_keystroke = false
3263 }
3264 self.window.pending_modifier.modifiers = event.modifiers
3265 } else if let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() {
3266 self.window.pending_modifier.saw_keystroke = true;
3267 keystroke = Some(key_down_event.keystroke.clone());
3268 }
3269
3270 let Some(keystroke) = keystroke else {
3271 self.finish_dispatch_key_event(event, dispatch_path);
3272 return;
3273 };
3274
3275 let mut currently_pending = self.window.pending_input.take().unwrap_or_default();
3276 if currently_pending.focus.is_some() && currently_pending.focus != self.window.focus {
3277 currently_pending = PendingInput::default();
3278 }
3279
3280 let match_result = self.window.rendered_frame.dispatch_tree.dispatch_key(
3281 currently_pending.keystrokes,
3282 keystroke,
3283 &dispatch_path,
3284 );
3285 if !match_result.to_replay.is_empty() {
3286 self.replay_pending_input(match_result.to_replay)
3287 }
3288
3289 if !match_result.pending.is_empty() {
3290 currently_pending.keystrokes = match_result.pending;
3291 currently_pending.focus = self.window.focus;
3292 currently_pending.timer = Some(self.spawn(|mut cx| async move {
3293 cx.background_executor.timer(Duration::from_secs(1)).await;
3294 cx.update(move |cx| {
3295 let Some(currently_pending) = cx
3296 .window
3297 .pending_input
3298 .take()
3299 .filter(|pending| pending.focus == cx.window.focus)
3300 else {
3301 return;
3302 };
3303
3304 let dispatch_path = cx
3305 .window
3306 .rendered_frame
3307 .dispatch_tree
3308 .dispatch_path(node_id);
3309
3310 let to_replay = cx
3311 .window
3312 .rendered_frame
3313 .dispatch_tree
3314 .flush_dispatch(currently_pending.keystrokes, &dispatch_path);
3315
3316 cx.replay_pending_input(to_replay)
3317 })
3318 .log_err();
3319 }));
3320 self.window.pending_input = Some(currently_pending);
3321 self.pending_input_changed();
3322 self.propagate_event = false;
3323 return;
3324 }
3325
3326 self.pending_input_changed();
3327 self.propagate_event = true;
3328 for binding in match_result.bindings {
3329 self.dispatch_action_on_node(node_id, binding.action.as_ref());
3330 if !self.propagate_event {
3331 self.dispatch_keystroke_observers(event, Some(binding.action));
3332 return;
3333 }
3334 }
3335
3336 self.finish_dispatch_key_event(event, dispatch_path)
3337 }
3338
3339 fn finish_dispatch_key_event(
3340 &mut self,
3341 event: &dyn Any,
3342 dispatch_path: SmallVec<[DispatchNodeId; 32]>,
3343 ) {
3344 self.dispatch_key_down_up_event(event, &dispatch_path);
3345 if !self.propagate_event {
3346 return;
3347 }
3348
3349 self.dispatch_modifiers_changed_event(event, &dispatch_path);
3350 if !self.propagate_event {
3351 return;
3352 }
3353
3354 self.dispatch_keystroke_observers(event, None);
3355 }
3356
3357 fn pending_input_changed(&mut self) {
3358 self.window
3359 .pending_input_observers
3360 .clone()
3361 .retain(&(), |callback| callback(self));
3362 }
3363
3364 fn dispatch_key_down_up_event(
3365 &mut self,
3366 event: &dyn Any,
3367 dispatch_path: &SmallVec<[DispatchNodeId; 32]>,
3368 ) {
3369 // Capture phase
3370 for node_id in dispatch_path {
3371 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3372
3373 for key_listener in node.key_listeners.clone() {
3374 key_listener(event, DispatchPhase::Capture, self);
3375 if !self.propagate_event {
3376 return;
3377 }
3378 }
3379 }
3380
3381 // Bubble phase
3382 for node_id in dispatch_path.iter().rev() {
3383 // Handle low level key events
3384 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3385 for key_listener in node.key_listeners.clone() {
3386 key_listener(event, DispatchPhase::Bubble, self);
3387 if !self.propagate_event {
3388 return;
3389 }
3390 }
3391 }
3392 }
3393
3394 fn dispatch_modifiers_changed_event(
3395 &mut self,
3396 event: &dyn Any,
3397 dispatch_path: &SmallVec<[DispatchNodeId; 32]>,
3398 ) {
3399 let Some(event) = event.downcast_ref::<ModifiersChangedEvent>() else {
3400 return;
3401 };
3402 for node_id in dispatch_path.iter().rev() {
3403 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3404 for listener in node.modifiers_changed_listeners.clone() {
3405 listener(event, self);
3406 if !self.propagate_event {
3407 return;
3408 }
3409 }
3410 }
3411 }
3412
3413 /// Determine whether a potential multi-stroke key binding is in progress on this window.
3414 pub fn has_pending_keystrokes(&self) -> bool {
3415 self.window.pending_input.is_some()
3416 }
3417
3418 fn clear_pending_keystrokes(&mut self) {
3419 self.window.pending_input.take();
3420 }
3421
3422 /// Returns the currently pending input keystrokes that might result in a multi-stroke key binding.
3423 pub fn pending_input_keystrokes(&self) -> Option<&[Keystroke]> {
3424 self.window
3425 .pending_input
3426 .as_ref()
3427 .map(|pending_input| pending_input.keystrokes.as_slice())
3428 }
3429
3430 fn replay_pending_input(&mut self, replays: SmallVec<[Replay; 1]>) {
3431 let node_id = self
3432 .window
3433 .focus
3434 .and_then(|focus_id| {
3435 self.window
3436 .rendered_frame
3437 .dispatch_tree
3438 .focusable_node_id(focus_id)
3439 })
3440 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3441
3442 let dispatch_path = self
3443 .window
3444 .rendered_frame
3445 .dispatch_tree
3446 .dispatch_path(node_id);
3447
3448 'replay: for replay in replays {
3449 let event = KeyDownEvent {
3450 keystroke: replay.keystroke.clone(),
3451 is_held: false,
3452 };
3453
3454 self.propagate_event = true;
3455 for binding in replay.bindings {
3456 self.dispatch_action_on_node(node_id, binding.action.as_ref());
3457 if !self.propagate_event {
3458 self.dispatch_keystroke_observers(&event, Some(binding.action));
3459 continue 'replay;
3460 }
3461 }
3462
3463 self.dispatch_key_down_up_event(&event, &dispatch_path);
3464 if !self.propagate_event {
3465 continue 'replay;
3466 }
3467 if let Some(input) = replay.keystroke.ime_key.as_ref().cloned() {
3468 if let Some(mut input_handler) = self.window.platform_window.take_input_handler() {
3469 input_handler.dispatch_input(&input, self);
3470 self.window.platform_window.set_input_handler(input_handler)
3471 }
3472 }
3473 }
3474 }
3475
3476 fn dispatch_action_on_node(&mut self, node_id: DispatchNodeId, action: &dyn Action) {
3477 let dispatch_path = self
3478 .window
3479 .rendered_frame
3480 .dispatch_tree
3481 .dispatch_path(node_id);
3482
3483 // Capture phase for global actions.
3484 self.propagate_event = true;
3485 if let Some(mut global_listeners) = self
3486 .global_action_listeners
3487 .remove(&action.as_any().type_id())
3488 {
3489 for listener in &global_listeners {
3490 listener(action.as_any(), DispatchPhase::Capture, self);
3491 if !self.propagate_event {
3492 break;
3493 }
3494 }
3495
3496 global_listeners.extend(
3497 self.global_action_listeners
3498 .remove(&action.as_any().type_id())
3499 .unwrap_or_default(),
3500 );
3501
3502 self.global_action_listeners
3503 .insert(action.as_any().type_id(), global_listeners);
3504 }
3505
3506 if !self.propagate_event {
3507 return;
3508 }
3509
3510 // Capture phase for window actions.
3511 for node_id in &dispatch_path {
3512 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3513 for DispatchActionListener {
3514 action_type,
3515 listener,
3516 } in node.action_listeners.clone()
3517 {
3518 let any_action = action.as_any();
3519 if action_type == any_action.type_id() {
3520 listener(any_action, DispatchPhase::Capture, self);
3521
3522 if !self.propagate_event {
3523 return;
3524 }
3525 }
3526 }
3527 }
3528
3529 // Bubble phase for window actions.
3530 for node_id in dispatch_path.iter().rev() {
3531 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3532 for DispatchActionListener {
3533 action_type,
3534 listener,
3535 } in node.action_listeners.clone()
3536 {
3537 let any_action = action.as_any();
3538 if action_type == any_action.type_id() {
3539 self.propagate_event = false; // Actions stop propagation by default during the bubble phase
3540 listener(any_action, DispatchPhase::Bubble, self);
3541
3542 if !self.propagate_event {
3543 return;
3544 }
3545 }
3546 }
3547 }
3548
3549 // Bubble phase for global actions.
3550 if let Some(mut global_listeners) = self
3551 .global_action_listeners
3552 .remove(&action.as_any().type_id())
3553 {
3554 for listener in global_listeners.iter().rev() {
3555 self.propagate_event = false; // Actions stop propagation by default during the bubble phase
3556
3557 listener(action.as_any(), DispatchPhase::Bubble, self);
3558 if !self.propagate_event {
3559 break;
3560 }
3561 }
3562
3563 global_listeners.extend(
3564 self.global_action_listeners
3565 .remove(&action.as_any().type_id())
3566 .unwrap_or_default(),
3567 );
3568
3569 self.global_action_listeners
3570 .insert(action.as_any().type_id(), global_listeners);
3571 }
3572 }
3573
3574 /// Register the given handler to be invoked whenever the global of the given type
3575 /// is updated.
3576 pub fn observe_global<G: Global>(
3577 &mut self,
3578 f: impl Fn(&mut WindowContext<'_>) + 'static,
3579 ) -> Subscription {
3580 let window_handle = self.window.handle;
3581 let (subscription, activate) = self.global_observers.insert(
3582 TypeId::of::<G>(),
3583 Box::new(move |cx| window_handle.update(cx, |_, cx| f(cx)).is_ok()),
3584 );
3585 self.app.defer(move |_| activate());
3586 subscription
3587 }
3588
3589 /// Focus the current window and bring it to the foreground at the platform level.
3590 pub fn activate_window(&self) {
3591 self.window.platform_window.activate();
3592 }
3593
3594 /// Minimize the current window at the platform level.
3595 pub fn minimize_window(&self) {
3596 self.window.platform_window.minimize();
3597 }
3598
3599 /// Toggle full screen status on the current window at the platform level.
3600 pub fn toggle_fullscreen(&self) {
3601 self.window.platform_window.toggle_fullscreen();
3602 }
3603
3604 /// Present a platform dialog.
3605 /// The provided message will be presented, along with buttons for each answer.
3606 /// When a button is clicked, the returned Receiver will receive the index of the clicked button.
3607 pub fn prompt(
3608 &mut self,
3609 level: PromptLevel,
3610 message: &str,
3611 detail: Option<&str>,
3612 answers: &[&str],
3613 ) -> oneshot::Receiver<usize> {
3614 let prompt_builder = self.app.prompt_builder.take();
3615 let Some(prompt_builder) = prompt_builder else {
3616 unreachable!("Re-entrant window prompting is not supported by GPUI");
3617 };
3618
3619 let receiver = match &prompt_builder {
3620 PromptBuilder::Default => self
3621 .window
3622 .platform_window
3623 .prompt(level, message, detail, answers)
3624 .unwrap_or_else(|| {
3625 self.build_custom_prompt(&prompt_builder, level, message, detail, answers)
3626 }),
3627 PromptBuilder::Custom(_) => {
3628 self.build_custom_prompt(&prompt_builder, level, message, detail, answers)
3629 }
3630 };
3631
3632 self.app.prompt_builder = Some(prompt_builder);
3633
3634 receiver
3635 }
3636
3637 fn build_custom_prompt(
3638 &mut self,
3639 prompt_builder: &PromptBuilder,
3640 level: PromptLevel,
3641 message: &str,
3642 detail: Option<&str>,
3643 answers: &[&str],
3644 ) -> oneshot::Receiver<usize> {
3645 let (sender, receiver) = oneshot::channel();
3646 let handle = PromptHandle::new(sender);
3647 let handle = (prompt_builder)(level, message, detail, answers, handle, self);
3648 self.window.prompt = Some(handle);
3649 receiver
3650 }
3651
3652 /// Returns all available actions for the focused element.
3653 pub fn available_actions(&self) -> Vec<Box<dyn Action>> {
3654 let node_id = self
3655 .window
3656 .focus
3657 .and_then(|focus_id| {
3658 self.window
3659 .rendered_frame
3660 .dispatch_tree
3661 .focusable_node_id(focus_id)
3662 })
3663 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3664
3665 let mut actions = self
3666 .window
3667 .rendered_frame
3668 .dispatch_tree
3669 .available_actions(node_id);
3670 for action_type in self.global_action_listeners.keys() {
3671 if let Err(ix) = actions.binary_search_by_key(action_type, |a| a.as_any().type_id()) {
3672 let action = self.actions.build_action_type(action_type).ok();
3673 if let Some(action) = action {
3674 actions.insert(ix, action);
3675 }
3676 }
3677 }
3678 actions
3679 }
3680
3681 /// Returns key bindings that invoke the given action on the currently focused element.
3682 pub fn bindings_for_action(&self, action: &dyn Action) -> Vec<KeyBinding> {
3683 self.window
3684 .rendered_frame
3685 .dispatch_tree
3686 .bindings_for_action(
3687 action,
3688 &self.window.rendered_frame.dispatch_tree.context_stack,
3689 )
3690 }
3691
3692 /// Returns any bindings that would invoke the given action on the given focus handle if it were focused.
3693 pub fn bindings_for_action_in(
3694 &self,
3695 action: &dyn Action,
3696 focus_handle: &FocusHandle,
3697 ) -> Vec<KeyBinding> {
3698 let dispatch_tree = &self.window.rendered_frame.dispatch_tree;
3699
3700 let Some(node_id) = dispatch_tree.focusable_node_id(focus_handle.id) else {
3701 return vec![];
3702 };
3703 let context_stack: Vec<_> = dispatch_tree
3704 .dispatch_path(node_id)
3705 .into_iter()
3706 .filter_map(|node_id| dispatch_tree.node(node_id).context.clone())
3707 .collect();
3708 dispatch_tree.bindings_for_action(action, &context_stack)
3709 }
3710
3711 /// Returns a generic event listener that invokes the given listener with the view and context associated with the given view handle.
3712 pub fn listener_for<V: Render, E>(
3713 &self,
3714 view: &View<V>,
3715 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
3716 ) -> impl Fn(&E, &mut WindowContext) + 'static {
3717 let view = view.downgrade();
3718 move |e: &E, cx: &mut WindowContext| {
3719 view.update(cx, |view, cx| f(view, e, cx)).ok();
3720 }
3721 }
3722
3723 /// Returns a generic handler that invokes the given handler with the view and context associated with the given view handle.
3724 pub fn handler_for<V: Render>(
3725 &self,
3726 view: &View<V>,
3727 f: impl Fn(&mut V, &mut ViewContext<V>) + 'static,
3728 ) -> impl Fn(&mut WindowContext) {
3729 let view = view.downgrade();
3730 move |cx: &mut WindowContext| {
3731 view.update(cx, |view, cx| f(view, cx)).ok();
3732 }
3733 }
3734
3735 /// Register a callback that can interrupt the closing of the current window based the returned boolean.
3736 /// If the callback returns false, the window won't be closed.
3737 pub fn on_window_should_close(&mut self, f: impl Fn(&mut WindowContext) -> bool + 'static) {
3738 let mut this = self.to_async();
3739 self.window
3740 .platform_window
3741 .on_should_close(Box::new(move || this.update(|cx| f(cx)).unwrap_or(true)))
3742 }
3743
3744 /// Register an action listener on the window for the next frame. The type of action
3745 /// is determined by the first parameter of the given listener. When the next frame is rendered
3746 /// the listener will be cleared.
3747 ///
3748 /// This is a fairly low-level method, so prefer using action handlers on elements unless you have
3749 /// a specific need to register a global listener.
3750 pub fn on_action(
3751 &mut self,
3752 action_type: TypeId,
3753 listener: impl Fn(&dyn Any, DispatchPhase, &mut WindowContext) + 'static,
3754 ) {
3755 self.window
3756 .next_frame
3757 .dispatch_tree
3758 .on_action(action_type, Rc::new(listener));
3759 }
3760
3761 /// Read information about the GPU backing this window.
3762 /// Currently returns None on Mac and Windows.
3763 pub fn gpu_specs(&self) -> Option<GPUSpecs> {
3764 self.window.platform_window.gpu_specs()
3765 }
3766}
3767
3768#[cfg(target_os = "windows")]
3769impl WindowContext<'_> {
3770 /// Returns the raw HWND handle for the window.
3771 pub fn get_raw_handle(&self) -> windows::Win32::Foundation::HWND {
3772 self.window.platform_window.get_raw_handle()
3773 }
3774}
3775
3776impl Context for WindowContext<'_> {
3777 type Result<T> = T;
3778
3779 fn new_model<T>(&mut self, build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T) -> Model<T>
3780 where
3781 T: 'static,
3782 {
3783 let slot = self.app.entities.reserve();
3784 let model = build_model(&mut ModelContext::new(&mut *self.app, slot.downgrade()));
3785 self.entities.insert(slot, model)
3786 }
3787
3788 fn reserve_model<T: 'static>(&mut self) -> Self::Result<crate::Reservation<T>> {
3789 self.app.reserve_model()
3790 }
3791
3792 fn insert_model<T: 'static>(
3793 &mut self,
3794 reservation: crate::Reservation<T>,
3795 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
3796 ) -> Self::Result<Model<T>> {
3797 self.app.insert_model(reservation, build_model)
3798 }
3799
3800 fn update_model<T: 'static, R>(
3801 &mut self,
3802 model: &Model<T>,
3803 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
3804 ) -> R {
3805 let mut entity = self.entities.lease(model);
3806 let result = update(
3807 &mut *entity,
3808 &mut ModelContext::new(&mut *self.app, model.downgrade()),
3809 );
3810 self.entities.end_lease(entity);
3811 result
3812 }
3813
3814 fn read_model<T, R>(
3815 &self,
3816 handle: &Model<T>,
3817 read: impl FnOnce(&T, &AppContext) -> R,
3818 ) -> Self::Result<R>
3819 where
3820 T: 'static,
3821 {
3822 let entity = self.entities.read(handle);
3823 read(entity, &*self.app)
3824 }
3825
3826 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
3827 where
3828 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
3829 {
3830 if window == self.window.handle {
3831 let root_view = self.window.root_view.clone().unwrap();
3832 Ok(update(root_view, self))
3833 } else {
3834 window.update(self.app, update)
3835 }
3836 }
3837
3838 fn read_window<T, R>(
3839 &self,
3840 window: &WindowHandle<T>,
3841 read: impl FnOnce(View<T>, &AppContext) -> R,
3842 ) -> Result<R>
3843 where
3844 T: 'static,
3845 {
3846 if window.any_handle == self.window.handle {
3847 let root_view = self
3848 .window
3849 .root_view
3850 .clone()
3851 .unwrap()
3852 .downcast::<T>()
3853 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
3854 Ok(read(root_view, self))
3855 } else {
3856 self.app.read_window(window, read)
3857 }
3858 }
3859}
3860
3861impl VisualContext for WindowContext<'_> {
3862 fn new_view<V>(
3863 &mut self,
3864 build_view_state: impl FnOnce(&mut ViewContext<'_, V>) -> V,
3865 ) -> Self::Result<View<V>>
3866 where
3867 V: 'static + Render,
3868 {
3869 let slot = self.app.entities.reserve();
3870 let view = View {
3871 model: slot.clone(),
3872 };
3873 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
3874 let entity = build_view_state(&mut cx);
3875 cx.entities.insert(slot, entity);
3876
3877 // Non-generic part to avoid leaking SubscriberSet to invokers of `new_view`.
3878 fn notify_observers(cx: &mut WindowContext, tid: TypeId, view: AnyView) {
3879 cx.new_view_observers.clone().retain(&tid, |observer| {
3880 let any_view = view.clone();
3881 (observer)(any_view, cx);
3882 true
3883 });
3884 }
3885 notify_observers(self, TypeId::of::<V>(), AnyView::from(view.clone()));
3886
3887 view
3888 }
3889
3890 /// Updates the given view. Prefer calling [`View::update`] instead, which calls this method.
3891 fn update_view<T: 'static, R>(
3892 &mut self,
3893 view: &View<T>,
3894 update: impl FnOnce(&mut T, &mut ViewContext<'_, T>) -> R,
3895 ) -> Self::Result<R> {
3896 let mut lease = self.app.entities.lease(&view.model);
3897 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, view);
3898 let result = update(&mut *lease, &mut cx);
3899 cx.app.entities.end_lease(lease);
3900 result
3901 }
3902
3903 fn replace_root_view<V>(
3904 &mut self,
3905 build_view: impl FnOnce(&mut ViewContext<'_, V>) -> V,
3906 ) -> Self::Result<View<V>>
3907 where
3908 V: 'static + Render,
3909 {
3910 let view = self.new_view(build_view);
3911 self.window.root_view = Some(view.clone().into());
3912 self.refresh();
3913 view
3914 }
3915
3916 fn focus_view<V: crate::FocusableView>(&mut self, view: &View<V>) -> Self::Result<()> {
3917 self.update_view(view, |view, cx| {
3918 view.focus_handle(cx).clone().focus(cx);
3919 })
3920 }
3921
3922 fn dismiss_view<V>(&mut self, view: &View<V>) -> Self::Result<()>
3923 where
3924 V: ManagedView,
3925 {
3926 self.update_view(view, |_, cx| cx.emit(DismissEvent))
3927 }
3928}
3929
3930impl<'a> std::ops::Deref for WindowContext<'a> {
3931 type Target = AppContext;
3932
3933 fn deref(&self) -> &Self::Target {
3934 self.app
3935 }
3936}
3937
3938impl<'a> std::ops::DerefMut for WindowContext<'a> {
3939 fn deref_mut(&mut self) -> &mut Self::Target {
3940 self.app
3941 }
3942}
3943
3944impl<'a> Borrow<AppContext> for WindowContext<'a> {
3945 fn borrow(&self) -> &AppContext {
3946 self.app
3947 }
3948}
3949
3950impl<'a> BorrowMut<AppContext> for WindowContext<'a> {
3951 fn borrow_mut(&mut self) -> &mut AppContext {
3952 self.app
3953 }
3954}
3955
3956/// This trait contains functionality that is shared across [`ViewContext`] and [`WindowContext`]
3957pub trait BorrowWindow: BorrowMut<Window> + BorrowMut<AppContext> {
3958 #[doc(hidden)]
3959 fn app_mut(&mut self) -> &mut AppContext {
3960 self.borrow_mut()
3961 }
3962
3963 #[doc(hidden)]
3964 fn app(&self) -> &AppContext {
3965 self.borrow()
3966 }
3967
3968 #[doc(hidden)]
3969 fn window(&self) -> &Window {
3970 self.borrow()
3971 }
3972
3973 #[doc(hidden)]
3974 fn window_mut(&mut self) -> &mut Window {
3975 self.borrow_mut()
3976 }
3977}
3978
3979impl Borrow<Window> for WindowContext<'_> {
3980 fn borrow(&self) -> &Window {
3981 self.window
3982 }
3983}
3984
3985impl BorrowMut<Window> for WindowContext<'_> {
3986 fn borrow_mut(&mut self) -> &mut Window {
3987 self.window
3988 }
3989}
3990
3991impl<T> BorrowWindow for T where T: BorrowMut<AppContext> + BorrowMut<Window> {}
3992
3993/// Provides access to application state that is specialized for a particular [`View`].
3994/// Allows you to interact with focus, emit events, etc.
3995/// ViewContext also derefs to [`WindowContext`], giving you access to all of its methods as well.
3996/// When you call [`View::update`], you're passed a `&mut V` and an `&mut ViewContext<V>`.
3997pub struct ViewContext<'a, V> {
3998 window_cx: WindowContext<'a>,
3999 view: &'a View<V>,
4000}
4001
4002impl<V> Borrow<AppContext> for ViewContext<'_, V> {
4003 fn borrow(&self) -> &AppContext {
4004 &*self.window_cx.app
4005 }
4006}
4007
4008impl<V> BorrowMut<AppContext> for ViewContext<'_, V> {
4009 fn borrow_mut(&mut self) -> &mut AppContext {
4010 &mut *self.window_cx.app
4011 }
4012}
4013
4014impl<V> Borrow<Window> for ViewContext<'_, V> {
4015 fn borrow(&self) -> &Window {
4016 &*self.window_cx.window
4017 }
4018}
4019
4020impl<V> BorrowMut<Window> for ViewContext<'_, V> {
4021 fn borrow_mut(&mut self) -> &mut Window {
4022 &mut *self.window_cx.window
4023 }
4024}
4025
4026impl<'a, V: 'static> ViewContext<'a, V> {
4027 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window, view: &'a View<V>) -> Self {
4028 Self {
4029 window_cx: WindowContext::new(app, window),
4030 view,
4031 }
4032 }
4033
4034 /// Get the entity_id of this view.
4035 pub fn entity_id(&self) -> EntityId {
4036 self.view.entity_id()
4037 }
4038
4039 /// Get the view pointer underlying this context.
4040 pub fn view(&self) -> &View<V> {
4041 self.view
4042 }
4043
4044 /// Get the model underlying this view.
4045 pub fn model(&self) -> &Model<V> {
4046 &self.view.model
4047 }
4048
4049 /// Access the underlying window context.
4050 pub fn window_context(&mut self) -> &mut WindowContext<'a> {
4051 &mut self.window_cx
4052 }
4053
4054 /// Sets a given callback to be run on the next frame.
4055 pub fn on_next_frame(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static)
4056 where
4057 V: 'static,
4058 {
4059 let view = self.view().clone();
4060 self.window_cx.on_next_frame(move |cx| view.update(cx, f));
4061 }
4062
4063 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
4064 /// that are currently on the stack to be returned to the app.
4065 pub fn defer(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static) {
4066 let view = self.view().downgrade();
4067 self.window_cx.defer(move |cx| {
4068 view.update(cx, f).ok();
4069 });
4070 }
4071
4072 /// Observe another model or view for changes to its state, as tracked by [`ModelContext::notify`].
4073 pub fn observe<V2, E>(
4074 &mut self,
4075 entity: &E,
4076 mut on_notify: impl FnMut(&mut V, E, &mut ViewContext<'_, V>) + 'static,
4077 ) -> Subscription
4078 where
4079 V2: 'static,
4080 V: 'static,
4081 E: Entity<V2>,
4082 {
4083 let view = self.view().downgrade();
4084 let entity_id = entity.entity_id();
4085 let entity = entity.downgrade();
4086 let window_handle = self.window.handle;
4087 self.app.new_observer(
4088 entity_id,
4089 Box::new(move |cx| {
4090 window_handle
4091 .update(cx, |_, cx| {
4092 if let Some(handle) = E::upgrade_from(&entity) {
4093 view.update(cx, |this, cx| on_notify(this, handle, cx))
4094 .is_ok()
4095 } else {
4096 false
4097 }
4098 })
4099 .unwrap_or(false)
4100 }),
4101 )
4102 }
4103
4104 /// Subscribe to events emitted by another model or view.
4105 /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
4106 /// 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.
4107 pub fn subscribe<V2, E, Evt>(
4108 &mut self,
4109 entity: &E,
4110 mut on_event: impl FnMut(&mut V, E, &Evt, &mut ViewContext<'_, V>) + 'static,
4111 ) -> Subscription
4112 where
4113 V2: EventEmitter<Evt>,
4114 E: Entity<V2>,
4115 Evt: 'static,
4116 {
4117 let view = self.view().downgrade();
4118 let entity_id = entity.entity_id();
4119 let handle = entity.downgrade();
4120 let window_handle = self.window.handle;
4121 self.app.new_subscription(
4122 entity_id,
4123 (
4124 TypeId::of::<Evt>(),
4125 Box::new(move |event, cx| {
4126 window_handle
4127 .update(cx, |_, cx| {
4128 if let Some(handle) = E::upgrade_from(&handle) {
4129 let event = event.downcast_ref().expect("invalid event type");
4130 view.update(cx, |this, cx| on_event(this, handle, event, cx))
4131 .is_ok()
4132 } else {
4133 false
4134 }
4135 })
4136 .unwrap_or(false)
4137 }),
4138 ),
4139 )
4140 }
4141
4142 /// Register a callback to be invoked when the view is released.
4143 ///
4144 /// The callback receives a handle to the view's window. This handle may be
4145 /// invalid, if the window was closed before the view was released.
4146 pub fn on_release(
4147 &mut self,
4148 on_release: impl FnOnce(&mut V, AnyWindowHandle, &mut AppContext) + 'static,
4149 ) -> Subscription {
4150 let window_handle = self.window.handle;
4151 let (subscription, activate) = self.app.release_listeners.insert(
4152 self.view.model.entity_id,
4153 Box::new(move |this, cx| {
4154 let this = this.downcast_mut().expect("invalid entity type");
4155 on_release(this, window_handle, cx)
4156 }),
4157 );
4158 activate();
4159 subscription
4160 }
4161
4162 /// Register a callback to be invoked when the given Model or View is released.
4163 pub fn observe_release<V2, E>(
4164 &mut self,
4165 entity: &E,
4166 mut on_release: impl FnMut(&mut V, &mut V2, &mut ViewContext<'_, V>) + 'static,
4167 ) -> Subscription
4168 where
4169 V: 'static,
4170 V2: 'static,
4171 E: Entity<V2>,
4172 {
4173 let view = self.view().downgrade();
4174 let entity_id = entity.entity_id();
4175 let window_handle = self.window.handle;
4176 let (subscription, activate) = self.app.release_listeners.insert(
4177 entity_id,
4178 Box::new(move |entity, cx| {
4179 let entity = entity.downcast_mut().expect("invalid entity type");
4180 let _ = window_handle.update(cx, |_, cx| {
4181 view.update(cx, |this, cx| on_release(this, entity, cx))
4182 });
4183 }),
4184 );
4185 activate();
4186 subscription
4187 }
4188
4189 /// Indicate that this view has changed, which will invoke any observers and also mark the window as dirty.
4190 /// If this view or any of its ancestors are *cached*, notifying it will cause it or its ancestors to be redrawn.
4191 pub fn notify(&mut self) {
4192 self.window_cx.notify(self.view.entity_id());
4193 }
4194
4195 /// Register a callback to be invoked when the window is resized.
4196 pub fn observe_window_bounds(
4197 &mut self,
4198 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4199 ) -> Subscription {
4200 let view = self.view.downgrade();
4201 let (subscription, activate) = self.window.bounds_observers.insert(
4202 (),
4203 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
4204 );
4205 activate();
4206 subscription
4207 }
4208
4209 /// Register a callback to be invoked when the window is activated or deactivated.
4210 pub fn observe_window_activation(
4211 &mut self,
4212 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4213 ) -> Subscription {
4214 let view = self.view.downgrade();
4215 let (subscription, activate) = self.window.activation_observers.insert(
4216 (),
4217 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
4218 );
4219 activate();
4220 subscription
4221 }
4222
4223 /// Registers a callback to be invoked when the window appearance changes.
4224 pub fn observe_window_appearance(
4225 &mut self,
4226 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4227 ) -> Subscription {
4228 let view = self.view.downgrade();
4229 let (subscription, activate) = self.window.appearance_observers.insert(
4230 (),
4231 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
4232 );
4233 activate();
4234 subscription
4235 }
4236
4237 /// Register a callback to be invoked when the window's pending input changes.
4238 pub fn observe_pending_input(
4239 &mut self,
4240 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4241 ) -> Subscription {
4242 let view = self.view.downgrade();
4243 let (subscription, activate) = self.window.pending_input_observers.insert(
4244 (),
4245 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
4246 );
4247 activate();
4248 subscription
4249 }
4250
4251 /// Register a listener to be called when the given focus handle receives focus.
4252 /// Returns a subscription and persists until the subscription is dropped.
4253 pub fn on_focus(
4254 &mut self,
4255 handle: &FocusHandle,
4256 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4257 ) -> Subscription {
4258 let view = self.view.downgrade();
4259 let focus_id = handle.id;
4260 let (subscription, activate) =
4261 self.window.new_focus_listener(Box::new(move |event, cx| {
4262 view.update(cx, |view, cx| {
4263 if event.previous_focus_path.last() != Some(&focus_id)
4264 && event.current_focus_path.last() == Some(&focus_id)
4265 {
4266 listener(view, cx)
4267 }
4268 })
4269 .is_ok()
4270 }));
4271 self.app.defer(|_| activate());
4272 subscription
4273 }
4274
4275 /// Register a listener to be called when the given focus handle or one of its descendants receives focus.
4276 /// This does not fire if the given focus handle - or one of its descendants - was previously focused.
4277 /// Returns a subscription and persists until the subscription is dropped.
4278 pub fn on_focus_in(
4279 &mut self,
4280 handle: &FocusHandle,
4281 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4282 ) -> Subscription {
4283 let view = self.view.downgrade();
4284 let focus_id = handle.id;
4285 let (subscription, activate) =
4286 self.window.new_focus_listener(Box::new(move |event, cx| {
4287 view.update(cx, |view, cx| {
4288 if event.is_focus_in(focus_id) {
4289 listener(view, cx)
4290 }
4291 })
4292 .is_ok()
4293 }));
4294 self.app.defer(move |_| activate());
4295 subscription
4296 }
4297
4298 /// Register a listener to be called when the given focus handle loses focus.
4299 /// Returns a subscription and persists until the subscription is dropped.
4300 pub fn on_blur(
4301 &mut self,
4302 handle: &FocusHandle,
4303 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4304 ) -> Subscription {
4305 let view = self.view.downgrade();
4306 let focus_id = handle.id;
4307 let (subscription, activate) =
4308 self.window.new_focus_listener(Box::new(move |event, cx| {
4309 view.update(cx, |view, cx| {
4310 if event.previous_focus_path.last() == Some(&focus_id)
4311 && event.current_focus_path.last() != Some(&focus_id)
4312 {
4313 listener(view, cx)
4314 }
4315 })
4316 .is_ok()
4317 }));
4318 self.app.defer(move |_| activate());
4319 subscription
4320 }
4321
4322 /// Register a listener to be called when nothing in the window has focus.
4323 /// This typically happens when the node that was focused is removed from the tree,
4324 /// and this callback lets you chose a default place to restore the users focus.
4325 /// Returns a subscription and persists until the subscription is dropped.
4326 pub fn on_focus_lost(
4327 &mut self,
4328 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4329 ) -> Subscription {
4330 let view = self.view.downgrade();
4331 let (subscription, activate) = self.window.focus_lost_listeners.insert(
4332 (),
4333 Box::new(move |cx| view.update(cx, |view, cx| listener(view, cx)).is_ok()),
4334 );
4335 activate();
4336 subscription
4337 }
4338
4339 /// Register a listener to be called when the given focus handle or one of its descendants loses focus.
4340 /// Returns a subscription and persists until the subscription is dropped.
4341 pub fn on_focus_out(
4342 &mut self,
4343 handle: &FocusHandle,
4344 mut listener: impl FnMut(&mut V, FocusOutEvent, &mut ViewContext<V>) + 'static,
4345 ) -> Subscription {
4346 let view = self.view.downgrade();
4347 let focus_id = handle.id;
4348 let (subscription, activate) =
4349 self.window.new_focus_listener(Box::new(move |event, cx| {
4350 view.update(cx, |view, cx| {
4351 if let Some(blurred_id) = event.previous_focus_path.last().copied() {
4352 if event.is_focus_out(focus_id) {
4353 let event = FocusOutEvent {
4354 blurred: WeakFocusHandle {
4355 id: blurred_id,
4356 handles: Arc::downgrade(&cx.window.focus_handles),
4357 },
4358 };
4359 listener(view, event, cx)
4360 }
4361 }
4362 })
4363 .is_ok()
4364 }));
4365 self.app.defer(move |_| activate());
4366 subscription
4367 }
4368
4369 /// Schedule a future to be run asynchronously.
4370 /// The given callback is invoked with a [`WeakView<V>`] to avoid leaking the view for a long-running process.
4371 /// It's also given an [`AsyncWindowContext`], which can be used to access the state of the view across await points.
4372 /// The returned future will be polled on the main thread.
4373 pub fn spawn<Fut, R>(
4374 &mut self,
4375 f: impl FnOnce(WeakView<V>, AsyncWindowContext) -> Fut,
4376 ) -> Task<R>
4377 where
4378 R: 'static,
4379 Fut: Future<Output = R> + 'static,
4380 {
4381 let view = self.view().downgrade();
4382 self.window_cx.spawn(|cx| f(view, cx))
4383 }
4384
4385 /// Register a callback to be invoked when the given global state changes.
4386 pub fn observe_global<G: Global>(
4387 &mut self,
4388 mut f: impl FnMut(&mut V, &mut ViewContext<'_, V>) + 'static,
4389 ) -> Subscription {
4390 let window_handle = self.window.handle;
4391 let view = self.view().downgrade();
4392 let (subscription, activate) = self.global_observers.insert(
4393 TypeId::of::<G>(),
4394 Box::new(move |cx| {
4395 window_handle
4396 .update(cx, |_, cx| view.update(cx, |view, cx| f(view, cx)).is_ok())
4397 .unwrap_or(false)
4398 }),
4399 );
4400 self.app.defer(move |_| activate());
4401 subscription
4402 }
4403
4404 /// Register a callback to be invoked when the given Action type is dispatched to the window.
4405 pub fn on_action(
4406 &mut self,
4407 action_type: TypeId,
4408 listener: impl Fn(&mut V, &dyn Any, DispatchPhase, &mut ViewContext<V>) + 'static,
4409 ) {
4410 let handle = self.view().clone();
4411 self.window_cx
4412 .on_action(action_type, move |action, phase, cx| {
4413 handle.update(cx, |view, cx| {
4414 listener(view, action, phase, cx);
4415 })
4416 });
4417 }
4418
4419 /// Emit an event to be handled by any other views that have subscribed via [ViewContext::subscribe].
4420 pub fn emit<Evt>(&mut self, event: Evt)
4421 where
4422 Evt: 'static,
4423 V: EventEmitter<Evt>,
4424 {
4425 let emitter = self.view.model.entity_id;
4426 self.app.push_effect(Effect::Emit {
4427 emitter,
4428 event_type: TypeId::of::<Evt>(),
4429 event: Box::new(event),
4430 });
4431 }
4432
4433 /// Move focus to the current view, assuming it implements [`FocusableView`].
4434 pub fn focus_self(&mut self)
4435 where
4436 V: FocusableView,
4437 {
4438 self.defer(|view, cx| view.focus_handle(cx).focus(cx))
4439 }
4440
4441 /// Convenience method for accessing view state in an event callback.
4442 ///
4443 /// Many GPUI callbacks take the form of `Fn(&E, &mut WindowContext)`,
4444 /// but it's often useful to be able to access view state in these
4445 /// callbacks. This method provides a convenient way to do so.
4446 pub fn listener<E: ?Sized>(
4447 &self,
4448 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
4449 ) -> impl Fn(&E, &mut WindowContext) + 'static {
4450 let view = self.view().downgrade();
4451 move |e: &E, cx: &mut WindowContext| {
4452 view.update(cx, |view, cx| f(view, e, cx)).ok();
4453 }
4454 }
4455}
4456
4457impl<V> Context for ViewContext<'_, V> {
4458 type Result<U> = U;
4459
4460 fn new_model<T: 'static>(
4461 &mut self,
4462 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
4463 ) -> Model<T> {
4464 self.window_cx.new_model(build_model)
4465 }
4466
4467 fn reserve_model<T: 'static>(&mut self) -> Self::Result<crate::Reservation<T>> {
4468 self.window_cx.reserve_model()
4469 }
4470
4471 fn insert_model<T: 'static>(
4472 &mut self,
4473 reservation: crate::Reservation<T>,
4474 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
4475 ) -> Self::Result<Model<T>> {
4476 self.window_cx.insert_model(reservation, build_model)
4477 }
4478
4479 fn update_model<T: 'static, R>(
4480 &mut self,
4481 model: &Model<T>,
4482 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
4483 ) -> R {
4484 self.window_cx.update_model(model, update)
4485 }
4486
4487 fn read_model<T, R>(
4488 &self,
4489 handle: &Model<T>,
4490 read: impl FnOnce(&T, &AppContext) -> R,
4491 ) -> Self::Result<R>
4492 where
4493 T: 'static,
4494 {
4495 self.window_cx.read_model(handle, read)
4496 }
4497
4498 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
4499 where
4500 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
4501 {
4502 self.window_cx.update_window(window, update)
4503 }
4504
4505 fn read_window<T, R>(
4506 &self,
4507 window: &WindowHandle<T>,
4508 read: impl FnOnce(View<T>, &AppContext) -> R,
4509 ) -> Result<R>
4510 where
4511 T: 'static,
4512 {
4513 self.window_cx.read_window(window, read)
4514 }
4515}
4516
4517impl<V: 'static> VisualContext for ViewContext<'_, V> {
4518 fn new_view<W: Render + 'static>(
4519 &mut self,
4520 build_view_state: impl FnOnce(&mut ViewContext<'_, W>) -> W,
4521 ) -> Self::Result<View<W>> {
4522 self.window_cx.new_view(build_view_state)
4523 }
4524
4525 fn update_view<V2: 'static, R>(
4526 &mut self,
4527 view: &View<V2>,
4528 update: impl FnOnce(&mut V2, &mut ViewContext<'_, V2>) -> R,
4529 ) -> Self::Result<R> {
4530 self.window_cx.update_view(view, update)
4531 }
4532
4533 fn replace_root_view<W>(
4534 &mut self,
4535 build_view: impl FnOnce(&mut ViewContext<'_, W>) -> W,
4536 ) -> Self::Result<View<W>>
4537 where
4538 W: 'static + Render,
4539 {
4540 self.window_cx.replace_root_view(build_view)
4541 }
4542
4543 fn focus_view<W: FocusableView>(&mut self, view: &View<W>) -> Self::Result<()> {
4544 self.window_cx.focus_view(view)
4545 }
4546
4547 fn dismiss_view<W: ManagedView>(&mut self, view: &View<W>) -> Self::Result<()> {
4548 self.window_cx.dismiss_view(view)
4549 }
4550}
4551
4552impl<'a, V> std::ops::Deref for ViewContext<'a, V> {
4553 type Target = WindowContext<'a>;
4554
4555 fn deref(&self) -> &Self::Target {
4556 &self.window_cx
4557 }
4558}
4559
4560impl<'a, V> std::ops::DerefMut for ViewContext<'a, V> {
4561 fn deref_mut(&mut self) -> &mut Self::Target {
4562 &mut self.window_cx
4563 }
4564}
4565
4566// #[derive(Clone, Copy, Eq, PartialEq, Hash)]
4567slotmap::new_key_type! {
4568 /// A unique identifier for a window.
4569 pub struct WindowId;
4570}
4571
4572impl WindowId {
4573 /// Converts this window ID to a `u64`.
4574 pub fn as_u64(&self) -> u64 {
4575 self.0.as_ffi()
4576 }
4577}
4578
4579/// A handle to a window with a specific root view type.
4580/// Note that this does not keep the window alive on its own.
4581#[derive(Deref, DerefMut)]
4582pub struct WindowHandle<V> {
4583 #[deref]
4584 #[deref_mut]
4585 pub(crate) any_handle: AnyWindowHandle,
4586 state_type: PhantomData<V>,
4587}
4588
4589impl<V: 'static + Render> WindowHandle<V> {
4590 /// Creates a new handle from a window ID.
4591 /// This does not check if the root type of the window is `V`.
4592 pub fn new(id: WindowId) -> Self {
4593 WindowHandle {
4594 any_handle: AnyWindowHandle {
4595 id,
4596 state_type: TypeId::of::<V>(),
4597 },
4598 state_type: PhantomData,
4599 }
4600 }
4601
4602 /// Get the root view out of this window.
4603 ///
4604 /// This will fail if the window is closed or if the root view's type does not match `V`.
4605 pub fn root<C>(&self, cx: &mut C) -> Result<View<V>>
4606 where
4607 C: Context,
4608 {
4609 Flatten::flatten(cx.update_window(self.any_handle, |root_view, _| {
4610 root_view
4611 .downcast::<V>()
4612 .map_err(|_| anyhow!("the type of the window's root view has changed"))
4613 }))
4614 }
4615
4616 /// Updates the root view of this window.
4617 ///
4618 /// This will fail if the window has been closed or if the root view's type does not match
4619 pub fn update<C, R>(
4620 &self,
4621 cx: &mut C,
4622 update: impl FnOnce(&mut V, &mut ViewContext<'_, V>) -> R,
4623 ) -> Result<R>
4624 where
4625 C: Context,
4626 {
4627 cx.update_window(self.any_handle, |root_view, cx| {
4628 let view = root_view
4629 .downcast::<V>()
4630 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
4631 Ok(cx.update_view(&view, update))
4632 })?
4633 }
4634
4635 /// Read the root view out of this window.
4636 ///
4637 /// This will fail if the window is closed or if the root view's type does not match `V`.
4638 pub fn read<'a>(&self, cx: &'a AppContext) -> Result<&'a V> {
4639 let x = cx
4640 .windows
4641 .get(self.id)
4642 .and_then(|window| {
4643 window
4644 .as_ref()
4645 .and_then(|window| window.root_view.clone())
4646 .map(|root_view| root_view.downcast::<V>())
4647 })
4648 .ok_or_else(|| anyhow!("window not found"))?
4649 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
4650
4651 Ok(x.read(cx))
4652 }
4653
4654 /// Read the root view out of this window, with a callback
4655 ///
4656 /// This will fail if the window is closed or if the root view's type does not match `V`.
4657 pub fn read_with<C, R>(&self, cx: &C, read_with: impl FnOnce(&V, &AppContext) -> R) -> Result<R>
4658 where
4659 C: Context,
4660 {
4661 cx.read_window(self, |root_view, cx| read_with(root_view.read(cx), cx))
4662 }
4663
4664 /// Read the root view pointer off of this window.
4665 ///
4666 /// This will fail if the window is closed or if the root view's type does not match `V`.
4667 pub fn root_view<C>(&self, cx: &C) -> Result<View<V>>
4668 where
4669 C: Context,
4670 {
4671 cx.read_window(self, |root_view, _cx| root_view.clone())
4672 }
4673
4674 /// Check if this window is 'active'.
4675 ///
4676 /// Will return `None` if the window is closed or currently
4677 /// borrowed.
4678 pub fn is_active(&self, cx: &mut AppContext) -> Option<bool> {
4679 cx.update_window(self.any_handle, |_, cx| cx.is_window_active())
4680 .ok()
4681 }
4682}
4683
4684impl<V> Copy for WindowHandle<V> {}
4685
4686impl<V> Clone for WindowHandle<V> {
4687 fn clone(&self) -> Self {
4688 *self
4689 }
4690}
4691
4692impl<V> PartialEq for WindowHandle<V> {
4693 fn eq(&self, other: &Self) -> bool {
4694 self.any_handle == other.any_handle
4695 }
4696}
4697
4698impl<V> Eq for WindowHandle<V> {}
4699
4700impl<V> Hash for WindowHandle<V> {
4701 fn hash<H: Hasher>(&self, state: &mut H) {
4702 self.any_handle.hash(state);
4703 }
4704}
4705
4706impl<V: 'static> From<WindowHandle<V>> for AnyWindowHandle {
4707 fn from(val: WindowHandle<V>) -> Self {
4708 val.any_handle
4709 }
4710}
4711
4712unsafe impl<V> Send for WindowHandle<V> {}
4713unsafe impl<V> Sync for WindowHandle<V> {}
4714
4715/// A handle to a window with any root view type, which can be downcast to a window with a specific root view type.
4716#[derive(Copy, Clone, PartialEq, Eq, Hash)]
4717pub struct AnyWindowHandle {
4718 pub(crate) id: WindowId,
4719 state_type: TypeId,
4720}
4721
4722impl AnyWindowHandle {
4723 /// Get the ID of this window.
4724 pub fn window_id(&self) -> WindowId {
4725 self.id
4726 }
4727
4728 /// Attempt to convert this handle to a window handle with a specific root view type.
4729 /// If the types do not match, this will return `None`.
4730 pub fn downcast<T: 'static>(&self) -> Option<WindowHandle<T>> {
4731 if TypeId::of::<T>() == self.state_type {
4732 Some(WindowHandle {
4733 any_handle: *self,
4734 state_type: PhantomData,
4735 })
4736 } else {
4737 None
4738 }
4739 }
4740
4741 /// Updates the state of the root view of this window.
4742 ///
4743 /// This will fail if the window has been closed.
4744 pub fn update<C, R>(
4745 self,
4746 cx: &mut C,
4747 update: impl FnOnce(AnyView, &mut WindowContext<'_>) -> R,
4748 ) -> Result<R>
4749 where
4750 C: Context,
4751 {
4752 cx.update_window(self, update)
4753 }
4754
4755 /// Read the state of the root view of this window.
4756 ///
4757 /// This will fail if the window has been closed.
4758 pub fn read<T, C, R>(self, cx: &C, read: impl FnOnce(View<T>, &AppContext) -> R) -> Result<R>
4759 where
4760 C: Context,
4761 T: 'static,
4762 {
4763 let view = self
4764 .downcast::<T>()
4765 .context("the type of the window's root view has changed")?;
4766
4767 cx.read_window(&view, read)
4768 }
4769}
4770
4771/// An identifier for an [`Element`](crate::Element).
4772///
4773/// Can be constructed with a string, a number, or both, as well
4774/// as other internal representations.
4775#[derive(Clone, Debug, Eq, PartialEq, Hash)]
4776pub enum ElementId {
4777 /// The ID of a View element
4778 View(EntityId),
4779 /// An integer ID.
4780 Integer(usize),
4781 /// A string based ID.
4782 Name(SharedString),
4783 /// A UUID.
4784 Uuid(Uuid),
4785 /// An ID that's equated with a focus handle.
4786 FocusHandle(FocusId),
4787 /// A combination of a name and an integer.
4788 NamedInteger(SharedString, usize),
4789}
4790
4791impl Display for ElementId {
4792 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
4793 match self {
4794 ElementId::View(entity_id) => write!(f, "view-{}", entity_id)?,
4795 ElementId::Integer(ix) => write!(f, "{}", ix)?,
4796 ElementId::Name(name) => write!(f, "{}", name)?,
4797 ElementId::FocusHandle(_) => write!(f, "FocusHandle")?,
4798 ElementId::NamedInteger(s, i) => write!(f, "{}-{}", s, i)?,
4799 ElementId::Uuid(uuid) => write!(f, "{}", uuid)?,
4800 }
4801
4802 Ok(())
4803 }
4804}
4805
4806impl TryInto<SharedString> for ElementId {
4807 type Error = anyhow::Error;
4808
4809 fn try_into(self) -> anyhow::Result<SharedString> {
4810 if let ElementId::Name(name) = self {
4811 Ok(name)
4812 } else {
4813 Err(anyhow!("element id is not string"))
4814 }
4815 }
4816}
4817
4818impl From<usize> for ElementId {
4819 fn from(id: usize) -> Self {
4820 ElementId::Integer(id)
4821 }
4822}
4823
4824impl From<i32> for ElementId {
4825 fn from(id: i32) -> Self {
4826 Self::Integer(id as usize)
4827 }
4828}
4829
4830impl From<SharedString> for ElementId {
4831 fn from(name: SharedString) -> Self {
4832 ElementId::Name(name)
4833 }
4834}
4835
4836impl From<&'static str> for ElementId {
4837 fn from(name: &'static str) -> Self {
4838 ElementId::Name(name.into())
4839 }
4840}
4841
4842impl<'a> From<&'a FocusHandle> for ElementId {
4843 fn from(handle: &'a FocusHandle) -> Self {
4844 ElementId::FocusHandle(handle.id)
4845 }
4846}
4847
4848impl From<(&'static str, EntityId)> for ElementId {
4849 fn from((name, id): (&'static str, EntityId)) -> Self {
4850 ElementId::NamedInteger(name.into(), id.as_u64() as usize)
4851 }
4852}
4853
4854impl From<(&'static str, usize)> for ElementId {
4855 fn from((name, id): (&'static str, usize)) -> Self {
4856 ElementId::NamedInteger(name.into(), id)
4857 }
4858}
4859
4860impl From<(&'static str, u64)> for ElementId {
4861 fn from((name, id): (&'static str, u64)) -> Self {
4862 ElementId::NamedInteger(name.into(), id as usize)
4863 }
4864}
4865
4866impl From<Uuid> for ElementId {
4867 fn from(value: Uuid) -> Self {
4868 Self::Uuid(value)
4869 }
4870}
4871
4872impl From<(&'static str, u32)> for ElementId {
4873 fn from((name, id): (&'static str, u32)) -> Self {
4874 ElementId::NamedInteger(name.into(), id as usize)
4875 }
4876}
4877
4878/// A rectangle to be rendered in the window at the given position and size.
4879/// Passed as an argument [`WindowContext::paint_quad`].
4880#[derive(Clone)]
4881pub struct PaintQuad {
4882 /// The bounds of the quad within the window.
4883 pub bounds: Bounds<Pixels>,
4884 /// The radii of the quad's corners.
4885 pub corner_radii: Corners<Pixels>,
4886 /// The background color of the quad.
4887 pub background: Hsla,
4888 /// The widths of the quad's borders.
4889 pub border_widths: Edges<Pixels>,
4890 /// The color of the quad's borders.
4891 pub border_color: Hsla,
4892}
4893
4894impl PaintQuad {
4895 /// Sets the corner radii of the quad.
4896 pub fn corner_radii(self, corner_radii: impl Into<Corners<Pixels>>) -> Self {
4897 PaintQuad {
4898 corner_radii: corner_radii.into(),
4899 ..self
4900 }
4901 }
4902
4903 /// Sets the border widths of the quad.
4904 pub fn border_widths(self, border_widths: impl Into<Edges<Pixels>>) -> Self {
4905 PaintQuad {
4906 border_widths: border_widths.into(),
4907 ..self
4908 }
4909 }
4910
4911 /// Sets the border color of the quad.
4912 pub fn border_color(self, border_color: impl Into<Hsla>) -> Self {
4913 PaintQuad {
4914 border_color: border_color.into(),
4915 ..self
4916 }
4917 }
4918
4919 /// Sets the background color of the quad.
4920 pub fn background(self, background: impl Into<Hsla>) -> Self {
4921 PaintQuad {
4922 background: background.into(),
4923 ..self
4924 }
4925 }
4926}
4927
4928/// Creates a quad with the given parameters.
4929pub fn quad(
4930 bounds: Bounds<Pixels>,
4931 corner_radii: impl Into<Corners<Pixels>>,
4932 background: impl Into<Hsla>,
4933 border_widths: impl Into<Edges<Pixels>>,
4934 border_color: impl Into<Hsla>,
4935) -> PaintQuad {
4936 PaintQuad {
4937 bounds,
4938 corner_radii: corner_radii.into(),
4939 background: background.into(),
4940 border_widths: border_widths.into(),
4941 border_color: border_color.into(),
4942 }
4943}
4944
4945/// Creates a filled quad with the given bounds and background color.
4946pub fn fill(bounds: impl Into<Bounds<Pixels>>, background: impl Into<Hsla>) -> PaintQuad {
4947 PaintQuad {
4948 bounds: bounds.into(),
4949 corner_radii: (0.).into(),
4950 background: background.into(),
4951 border_widths: (0.).into(),
4952 border_color: transparent_black(),
4953 }
4954}
4955
4956/// Creates a rectangle outline with the given bounds, border color, and a 1px border width
4957pub fn outline(bounds: impl Into<Bounds<Pixels>>, border_color: impl Into<Hsla>) -> PaintQuad {
4958 PaintQuad {
4959 bounds: bounds.into(),
4960 corner_radii: (0.).into(),
4961 background: transparent_black(),
4962 border_widths: (1.).into(),
4963 border_color: border_color.into(),
4964 }
4965}