1use crate::{
2 hash, point, prelude::*, px, size, transparent_black, Action, AnyDrag, AnyElement, AnyTooltip,
3 AnyView, AppContext, Arena, Asset, AsyncWindowContext, AvailableSpace, Bounds, BoxShadow,
4 Context, Corners, CursorStyle, DevicePixels, DispatchActionListener, DispatchNodeId,
5 DispatchTree, DisplayId, Edges, Effect, Entity, EntityId, EventEmitter, FileDropEvent, Flatten,
6 FontId, Global, GlobalElementId, GlyphId, Hsla, ImageData, InputHandler, IsZero, KeyBinding,
7 KeyContext, KeyDownEvent, KeyEvent, KeyMatch, KeymatchResult, Keystroke, KeystrokeEvent,
8 LayoutId, LineLayoutIndex, Model, ModelContext, Modifiers, ModifiersChangedEvent,
9 MonochromeSprite, MouseButton, MouseEvent, MouseMoveEvent, MouseUpEvent, Path, Pixels,
10 PlatformAtlas, PlatformDisplay, PlatformInput, PlatformInputHandler, PlatformWindow, Point,
11 PolychromeSprite, PromptLevel, Quad, Render, RenderGlyphParams, RenderImageParams,
12 RenderSvgParams, ScaledPixels, Scene, Shadow, SharedString, Size, StrikethroughStyle, Style,
13 SubscriberSet, Subscription, TaffyLayoutEngine, Task, TextStyle, TextStyleRefinement,
14 TransformationMatrix, Underline, UnderlineStyle, View, VisualContext, WeakView,
15 WindowAppearance, WindowBackgroundAppearance, WindowBounds, WindowOptions, WindowParams,
16 WindowTextSystem, SUBPIXEL_VARIANTS,
17};
18use anyhow::{anyhow, Context as _, Result};
19use collections::{FxHashMap, FxHashSet};
20use derive_more::{Deref, DerefMut};
21use futures::channel::oneshot;
22use futures::{future::Shared, FutureExt};
23#[cfg(target_os = "macos")]
24use media::core_video::CVImageBuffer;
25use parking_lot::RwLock;
26use refineable::Refineable;
27use slotmap::SlotMap;
28use smallvec::SmallVec;
29use std::{
30 any::{Any, TypeId},
31 borrow::{Borrow, BorrowMut, Cow},
32 cell::{Cell, RefCell},
33 cmp,
34 fmt::{Debug, Display},
35 future::Future,
36 hash::{Hash, Hasher},
37 marker::PhantomData,
38 mem,
39 ops::Range,
40 rc::Rc,
41 sync::{
42 atomic::{AtomicUsize, Ordering::SeqCst},
43 Arc, Weak,
44 },
45 time::{Duration, Instant},
46};
47use util::post_inc;
48use util::{measure, ResultExt};
49use uuid::Uuid;
50
51mod prompts;
52
53pub use prompts::*;
54
55pub(crate) const DEFAULT_WINDOW_SIZE: Size<Pixels> = size(px(1024.), px(700.));
56
57/// Represents the two different phases when dispatching events.
58#[derive(Default, Copy, Clone, Debug, Eq, PartialEq)]
59pub enum DispatchPhase {
60 /// After the capture phase comes the bubble phase, in which mouse event listeners are
61 /// invoked front to back and keyboard event listeners are invoked from the focused element
62 /// to the root of the element tree. This is the phase you'll most commonly want to use when
63 /// registering event listeners.
64 #[default]
65 Bubble,
66 /// During the initial capture phase, mouse event listeners are invoked back to front, and keyboard
67 /// listeners are invoked from the root of the tree downward toward the focused element. This phase
68 /// is used for special purposes such as clearing the "pressed" state for click events. If
69 /// you stop event propagation during this phase, you need to know what you're doing. Handlers
70 /// outside of the immediate region may rely on detecting non-local events during this phase.
71 Capture,
72}
73
74impl DispatchPhase {
75 /// Returns true if this represents the "bubble" phase.
76 pub fn bubble(self) -> bool {
77 self == DispatchPhase::Bubble
78 }
79
80 /// Returns true if this represents the "capture" phase.
81 pub fn capture(self) -> bool {
82 self == DispatchPhase::Capture
83 }
84}
85
86type AnyObserver = Box<dyn FnMut(&mut WindowContext) -> bool + 'static>;
87
88type AnyWindowFocusListener = Box<dyn FnMut(&FocusEvent, &mut WindowContext) -> bool + 'static>;
89
90struct FocusEvent {
91 previous_focus_path: SmallVec<[FocusId; 8]>,
92 current_focus_path: SmallVec<[FocusId; 8]>,
93}
94
95slotmap::new_key_type! {
96 /// A globally unique identifier for a focusable element.
97 pub struct FocusId;
98}
99
100thread_local! {
101 /// 8MB wasn't quite enough...
102 pub(crate) static ELEMENT_ARENA: RefCell<Arena> = RefCell::new(Arena::new(32 * 1024 * 1024));
103}
104
105impl FocusId {
106 /// Obtains whether the element associated with this handle is currently focused.
107 pub fn is_focused(&self, cx: &WindowContext) -> bool {
108 cx.window.focus == Some(*self)
109 }
110
111 /// Obtains whether the element associated with this handle contains the focused
112 /// element or is itself focused.
113 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
114 cx.focused()
115 .map_or(false, |focused| self.contains(focused.id, cx))
116 }
117
118 /// Obtains whether the element associated with this handle is contained within the
119 /// focused element or is itself focused.
120 pub fn within_focused(&self, cx: &WindowContext) -> bool {
121 let focused = cx.focused();
122 focused.map_or(false, |focused| focused.id.contains(*self, cx))
123 }
124
125 /// Obtains whether this handle contains the given handle in the most recently rendered frame.
126 pub(crate) fn contains(&self, other: Self, cx: &WindowContext) -> bool {
127 cx.window
128 .rendered_frame
129 .dispatch_tree
130 .focus_contains(*self, other)
131 }
132}
133
134/// A handle which can be used to track and manipulate the focused element in a window.
135pub struct FocusHandle {
136 pub(crate) id: FocusId,
137 handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
138}
139
140impl std::fmt::Debug for FocusHandle {
141 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
142 f.write_fmt(format_args!("FocusHandle({:?})", self.id))
143 }
144}
145
146impl FocusHandle {
147 pub(crate) fn new(handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>) -> Self {
148 let id = handles.write().insert(AtomicUsize::new(1));
149 Self {
150 id,
151 handles: handles.clone(),
152 }
153 }
154
155 pub(crate) fn for_id(
156 id: FocusId,
157 handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
158 ) -> Option<Self> {
159 let lock = handles.read();
160 let ref_count = lock.get(id)?;
161 if ref_count.load(SeqCst) == 0 {
162 None
163 } else {
164 ref_count.fetch_add(1, SeqCst);
165 Some(Self {
166 id,
167 handles: handles.clone(),
168 })
169 }
170 }
171
172 /// Converts this focus handle into a weak variant, which does not prevent it from being released.
173 pub fn downgrade(&self) -> WeakFocusHandle {
174 WeakFocusHandle {
175 id: self.id,
176 handles: Arc::downgrade(&self.handles),
177 }
178 }
179
180 /// Moves the focus to the element associated with this handle.
181 pub fn focus(&self, cx: &mut WindowContext) {
182 cx.focus(self)
183 }
184
185 /// Obtains whether the element associated with this handle is currently focused.
186 pub fn is_focused(&self, cx: &WindowContext) -> bool {
187 self.id.is_focused(cx)
188 }
189
190 /// Obtains whether the element associated with this handle contains the focused
191 /// element or is itself focused.
192 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
193 self.id.contains_focused(cx)
194 }
195
196 /// Obtains whether the element associated with this handle is contained within the
197 /// focused element or is itself focused.
198 pub fn within_focused(&self, cx: &WindowContext) -> bool {
199 self.id.within_focused(cx)
200 }
201
202 /// Obtains whether this handle contains the given handle in the most recently rendered frame.
203 pub fn contains(&self, other: &Self, cx: &WindowContext) -> bool {
204 self.id.contains(other.id, cx)
205 }
206
207 /// Dispatch an action on the element that rendered this focus handle
208 pub fn dispatch_action(&self, action: &dyn Action, cx: &mut WindowContext) {
209 if let Some(node_id) = cx
210 .window
211 .rendered_frame
212 .dispatch_tree
213 .focusable_node_id(self.id)
214 {
215 cx.dispatch_action_on_node(node_id, action)
216 }
217 }
218}
219
220impl Clone for FocusHandle {
221 fn clone(&self) -> Self {
222 Self::for_id(self.id, &self.handles).unwrap()
223 }
224}
225
226impl PartialEq for FocusHandle {
227 fn eq(&self, other: &Self) -> bool {
228 self.id == other.id
229 }
230}
231
232impl Eq for FocusHandle {}
233
234impl Drop for FocusHandle {
235 fn drop(&mut self) {
236 self.handles
237 .read()
238 .get(self.id)
239 .unwrap()
240 .fetch_sub(1, SeqCst);
241 }
242}
243
244/// A weak reference to a focus handle.
245#[derive(Clone, Debug)]
246pub struct WeakFocusHandle {
247 pub(crate) id: FocusId,
248 handles: Weak<RwLock<SlotMap<FocusId, AtomicUsize>>>,
249}
250
251impl WeakFocusHandle {
252 /// Attempts to upgrade the [WeakFocusHandle] to a [FocusHandle].
253 pub fn upgrade(&self) -> Option<FocusHandle> {
254 let handles = self.handles.upgrade()?;
255 FocusHandle::for_id(self.id, &handles)
256 }
257}
258
259impl PartialEq for WeakFocusHandle {
260 fn eq(&self, other: &WeakFocusHandle) -> bool {
261 self.id == other.id
262 }
263}
264
265impl Eq for WeakFocusHandle {}
266
267impl PartialEq<FocusHandle> for WeakFocusHandle {
268 fn eq(&self, other: &FocusHandle) -> bool {
269 self.id == other.id
270 }
271}
272
273impl PartialEq<WeakFocusHandle> for FocusHandle {
274 fn eq(&self, other: &WeakFocusHandle) -> bool {
275 self.id == other.id
276 }
277}
278
279/// FocusableView allows users of your view to easily
280/// focus it (using cx.focus_view(view))
281pub trait FocusableView: 'static + Render {
282 /// Returns the focus handle associated with this view.
283 fn focus_handle(&self, cx: &AppContext) -> FocusHandle;
284}
285
286/// ManagedView is a view (like a Modal, Popover, Menu, etc.)
287/// where the lifecycle of the view is handled by another view.
288pub trait ManagedView: FocusableView + EventEmitter<DismissEvent> {}
289
290impl<M: FocusableView + EventEmitter<DismissEvent>> ManagedView for M {}
291
292/// Emitted by implementers of [`ManagedView`] to indicate the view should be dismissed, such as when a view is presented as a modal.
293pub struct DismissEvent;
294
295type FrameCallback = Box<dyn FnOnce(&mut WindowContext)>;
296
297pub(crate) type AnyMouseListener =
298 Box<dyn FnMut(&dyn Any, DispatchPhase, &mut WindowContext) + 'static>;
299
300#[derive(Clone)]
301pub(crate) struct CursorStyleRequest {
302 pub(crate) hitbox_id: HitboxId,
303 pub(crate) style: CursorStyle,
304}
305
306/// An identifier for a [Hitbox].
307#[derive(Copy, Clone, Debug, Default, Eq, PartialEq)]
308pub struct HitboxId(usize);
309
310impl HitboxId {
311 /// Checks if the hitbox with this id is currently hovered.
312 pub fn is_hovered(&self, cx: &WindowContext) -> bool {
313 cx.window.mouse_hit_test.0.contains(self)
314 }
315}
316
317/// A rectangular region that potentially blocks hitboxes inserted prior.
318/// See [WindowContext::insert_hitbox] for more details.
319#[derive(Clone, Debug, Deref)]
320pub struct Hitbox {
321 /// A unique identifier for the hitbox.
322 pub id: HitboxId,
323 /// The bounds of the hitbox.
324 #[deref]
325 pub bounds: Bounds<Pixels>,
326 /// The content mask when the hitbox was inserted.
327 pub content_mask: ContentMask<Pixels>,
328 /// Whether the hitbox occludes other hitboxes inserted prior.
329 pub opaque: bool,
330}
331
332impl Hitbox {
333 /// Checks if the hitbox is currently hovered.
334 pub fn is_hovered(&self, cx: &WindowContext) -> bool {
335 self.id.is_hovered(cx)
336 }
337}
338
339#[derive(Default, Eq, PartialEq)]
340pub(crate) struct HitTest(SmallVec<[HitboxId; 8]>);
341
342/// An identifier for a tooltip.
343#[derive(Copy, Clone, Debug, Default, Eq, PartialEq)]
344pub struct TooltipId(usize);
345
346impl TooltipId {
347 /// Checks if the tooltip is currently hovered.
348 pub fn is_hovered(&self, cx: &WindowContext) -> bool {
349 cx.window
350 .tooltip_bounds
351 .as_ref()
352 .map_or(false, |tooltip_bounds| {
353 tooltip_bounds.id == *self && tooltip_bounds.bounds.contains(&cx.mouse_position())
354 })
355 }
356}
357
358pub(crate) struct TooltipBounds {
359 id: TooltipId,
360 bounds: Bounds<Pixels>,
361}
362
363#[derive(Clone)]
364pub(crate) struct TooltipRequest {
365 id: TooltipId,
366 tooltip: AnyTooltip,
367}
368
369pub(crate) struct DeferredDraw {
370 priority: usize,
371 parent_node: DispatchNodeId,
372 element_id_stack: SmallVec<[ElementId; 32]>,
373 text_style_stack: Vec<TextStyleRefinement>,
374 element: Option<AnyElement>,
375 absolute_offset: Point<Pixels>,
376 prepaint_range: Range<PrepaintStateIndex>,
377 paint_range: Range<PaintIndex>,
378}
379
380pub(crate) struct Frame {
381 pub(crate) focus: Option<FocusId>,
382 pub(crate) window_active: bool,
383 pub(crate) element_states: FxHashMap<(GlobalElementId, TypeId), ElementStateBox>,
384 accessed_element_states: Vec<(GlobalElementId, TypeId)>,
385 pub(crate) mouse_listeners: Vec<Option<AnyMouseListener>>,
386 pub(crate) dispatch_tree: DispatchTree,
387 pub(crate) scene: Scene,
388 pub(crate) hitboxes: Vec<Hitbox>,
389 pub(crate) deferred_draws: Vec<DeferredDraw>,
390 pub(crate) input_handlers: Vec<Option<PlatformInputHandler>>,
391 pub(crate) tooltip_requests: Vec<Option<TooltipRequest>>,
392 pub(crate) cursor_styles: Vec<CursorStyleRequest>,
393 #[cfg(any(test, feature = "test-support"))]
394 pub(crate) debug_bounds: FxHashMap<String, Bounds<Pixels>>,
395}
396
397#[derive(Clone, Default)]
398pub(crate) struct PrepaintStateIndex {
399 hitboxes_index: usize,
400 tooltips_index: usize,
401 deferred_draws_index: usize,
402 dispatch_tree_index: usize,
403 accessed_element_states_index: usize,
404 line_layout_index: LineLayoutIndex,
405}
406
407#[derive(Clone, Default)]
408pub(crate) struct PaintIndex {
409 scene_index: usize,
410 mouse_listeners_index: usize,
411 input_handlers_index: usize,
412 cursor_styles_index: usize,
413 accessed_element_states_index: usize,
414 line_layout_index: LineLayoutIndex,
415}
416
417impl Frame {
418 pub(crate) fn new(dispatch_tree: DispatchTree) -> Self {
419 Frame {
420 focus: None,
421 window_active: false,
422 element_states: FxHashMap::default(),
423 accessed_element_states: Vec::new(),
424 mouse_listeners: Vec::new(),
425 dispatch_tree,
426 scene: Scene::default(),
427 hitboxes: Vec::new(),
428 deferred_draws: Vec::new(),
429 input_handlers: Vec::new(),
430 tooltip_requests: Vec::new(),
431 cursor_styles: Vec::new(),
432
433 #[cfg(any(test, feature = "test-support"))]
434 debug_bounds: FxHashMap::default(),
435 }
436 }
437
438 pub(crate) fn clear(&mut self) {
439 self.element_states.clear();
440 self.accessed_element_states.clear();
441 self.mouse_listeners.clear();
442 self.dispatch_tree.clear();
443 self.scene.clear();
444 self.input_handlers.clear();
445 self.tooltip_requests.clear();
446 self.cursor_styles.clear();
447 self.hitboxes.clear();
448 self.deferred_draws.clear();
449 }
450
451 pub(crate) fn hit_test(&self, position: Point<Pixels>) -> HitTest {
452 let mut hit_test = HitTest::default();
453 for hitbox in self.hitboxes.iter().rev() {
454 let bounds = hitbox.bounds.intersect(&hitbox.content_mask.bounds);
455 if bounds.contains(&position) {
456 hit_test.0.push(hitbox.id);
457 if hitbox.opaque {
458 break;
459 }
460 }
461 }
462 hit_test
463 }
464
465 pub(crate) fn focus_path(&self) -> SmallVec<[FocusId; 8]> {
466 self.focus
467 .map(|focus_id| self.dispatch_tree.focus_path(focus_id))
468 .unwrap_or_default()
469 }
470
471 pub(crate) fn finish(&mut self, prev_frame: &mut Self) {
472 for element_state_key in &self.accessed_element_states {
473 if let Some((element_state_key, element_state)) =
474 prev_frame.element_states.remove_entry(element_state_key)
475 {
476 self.element_states.insert(element_state_key, element_state);
477 }
478 }
479
480 self.scene.finish();
481 }
482}
483
484// Holds the state for a specific window.
485#[doc(hidden)]
486pub struct Window {
487 pub(crate) handle: AnyWindowHandle,
488 pub(crate) removed: bool,
489 pub(crate) platform_window: Box<dyn PlatformWindow>,
490 display_id: Option<DisplayId>,
491 sprite_atlas: Arc<dyn PlatformAtlas>,
492 text_system: Arc<WindowTextSystem>,
493 rem_size: Pixels,
494 /// The stack of override values for the window's rem size.
495 ///
496 /// This is used by `with_rem_size` to allow rendering an element tree with
497 /// a given rem size.
498 rem_size_override_stack: SmallVec<[Pixels; 8]>,
499 pub(crate) viewport_size: Size<Pixels>,
500 layout_engine: Option<TaffyLayoutEngine>,
501 pub(crate) root_view: Option<AnyView>,
502 pub(crate) element_id_stack: SmallVec<[ElementId; 32]>,
503 pub(crate) text_style_stack: Vec<TextStyleRefinement>,
504 pub(crate) element_offset_stack: Vec<Point<Pixels>>,
505 pub(crate) content_mask_stack: Vec<ContentMask<Pixels>>,
506 pub(crate) requested_autoscroll: Option<Bounds<Pixels>>,
507 pub(crate) rendered_frame: Frame,
508 pub(crate) next_frame: Frame,
509 pub(crate) next_hitbox_id: HitboxId,
510 pub(crate) next_tooltip_id: TooltipId,
511 pub(crate) tooltip_bounds: Option<TooltipBounds>,
512 next_frame_callbacks: Rc<RefCell<Vec<FrameCallback>>>,
513 pub(crate) dirty_views: FxHashSet<EntityId>,
514 pub(crate) focus_handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
515 focus_listeners: SubscriberSet<(), AnyWindowFocusListener>,
516 focus_lost_listeners: SubscriberSet<(), AnyObserver>,
517 default_prevented: bool,
518 mouse_position: Point<Pixels>,
519 mouse_hit_test: HitTest,
520 modifiers: Modifiers,
521 scale_factor: f32,
522 bounds_observers: SubscriberSet<(), AnyObserver>,
523 appearance: WindowAppearance,
524 appearance_observers: SubscriberSet<(), AnyObserver>,
525 active: Rc<Cell<bool>>,
526 pub(crate) dirty: Rc<Cell<bool>>,
527 pub(crate) needs_present: Rc<Cell<bool>>,
528 pub(crate) last_input_timestamp: Rc<Cell<Instant>>,
529 pub(crate) refreshing: bool,
530 pub(crate) draw_phase: DrawPhase,
531 activation_observers: SubscriberSet<(), AnyObserver>,
532 pub(crate) focus: Option<FocusId>,
533 focus_enabled: bool,
534 pending_input: Option<PendingInput>,
535 prompt: Option<RenderablePromptHandle>,
536}
537
538#[derive(Clone, Copy, Debug, Eq, PartialEq)]
539pub(crate) enum DrawPhase {
540 None,
541 Prepaint,
542 Paint,
543 Focus,
544}
545
546#[derive(Default, Debug)]
547struct PendingInput {
548 keystrokes: SmallVec<[Keystroke; 1]>,
549 bindings: SmallVec<[KeyBinding; 1]>,
550 focus: Option<FocusId>,
551 timer: Option<Task<()>>,
552}
553
554impl PendingInput {
555 fn input(&self) -> String {
556 self.keystrokes
557 .iter()
558 .flat_map(|k| k.ime_key.clone())
559 .collect::<Vec<String>>()
560 .join("")
561 }
562
563 fn used_by_binding(&self, binding: &KeyBinding) -> bool {
564 if self.keystrokes.is_empty() {
565 return true;
566 }
567 let keystroke = &self.keystrokes[0];
568 for candidate in keystroke.match_candidates() {
569 if binding.match_keystrokes(&[candidate]) == KeyMatch::Pending {
570 return true;
571 }
572 }
573 false
574 }
575}
576
577pub(crate) struct ElementStateBox {
578 pub(crate) inner: Box<dyn Any>,
579 #[cfg(debug_assertions)]
580 pub(crate) type_name: &'static str,
581}
582
583fn default_bounds(display_id: Option<DisplayId>, cx: &mut AppContext) -> Bounds<Pixels> {
584 const DEFAULT_WINDOW_OFFSET: Point<Pixels> = point(px(0.), px(35.));
585
586 cx.active_window()
587 .and_then(|w| w.update(cx, |_, cx| cx.bounds()).ok())
588 .map(|bounds| bounds.map_origin(|origin| origin + DEFAULT_WINDOW_OFFSET))
589 .unwrap_or_else(|| {
590 let display = display_id
591 .map(|id| cx.find_display(id))
592 .unwrap_or_else(|| cx.primary_display());
593
594 display
595 .map(|display| display.default_bounds())
596 .unwrap_or_else(|| Bounds::new(point(px(0.), px(0.)), DEFAULT_WINDOW_SIZE))
597 })
598}
599
600impl Window {
601 pub(crate) fn new(
602 handle: AnyWindowHandle,
603 options: WindowOptions,
604 cx: &mut AppContext,
605 ) -> Result<Self> {
606 let WindowOptions {
607 window_bounds,
608 titlebar,
609 focus,
610 show,
611 kind,
612 is_movable,
613 display_id,
614 window_background,
615 app_id,
616 } = options;
617
618 let bounds = window_bounds
619 .map(|bounds| bounds.get_bounds())
620 .unwrap_or_else(|| default_bounds(display_id, cx));
621 let mut platform_window = cx.platform.open_window(
622 handle,
623 WindowParams {
624 bounds,
625 titlebar,
626 kind,
627 is_movable,
628 focus,
629 show,
630 display_id,
631 window_background,
632 },
633 )?;
634 let display_id = platform_window.display().map(|display| display.id());
635 let sprite_atlas = platform_window.sprite_atlas();
636 let mouse_position = platform_window.mouse_position();
637 let modifiers = platform_window.modifiers();
638 let content_size = platform_window.content_size();
639 let scale_factor = platform_window.scale_factor();
640 let appearance = platform_window.appearance();
641 let text_system = Arc::new(WindowTextSystem::new(cx.text_system().clone()));
642 let dirty = Rc::new(Cell::new(true));
643 let active = Rc::new(Cell::new(platform_window.is_active()));
644 let needs_present = Rc::new(Cell::new(false));
645 let next_frame_callbacks: Rc<RefCell<Vec<FrameCallback>>> = Default::default();
646 let last_input_timestamp = Rc::new(Cell::new(Instant::now()));
647
648 if let Some(ref window_open_state) = window_bounds {
649 match window_open_state {
650 WindowBounds::Fullscreen(_) => platform_window.toggle_fullscreen(),
651 WindowBounds::Maximized(_) => platform_window.zoom(),
652 WindowBounds::Windowed(_) => {}
653 }
654 }
655
656 platform_window.on_close(Box::new({
657 let mut cx = cx.to_async();
658 move || {
659 let _ = handle.update(&mut cx, |_, cx| cx.remove_window());
660 }
661 }));
662 platform_window.on_request_frame(Box::new({
663 let mut cx = cx.to_async();
664 let dirty = dirty.clone();
665 let active = active.clone();
666 let needs_present = needs_present.clone();
667 let next_frame_callbacks = next_frame_callbacks.clone();
668 let last_input_timestamp = last_input_timestamp.clone();
669 move || {
670 let next_frame_callbacks = next_frame_callbacks.take();
671 if !next_frame_callbacks.is_empty() {
672 handle
673 .update(&mut cx, |_, cx| {
674 for callback in next_frame_callbacks {
675 callback(cx);
676 }
677 })
678 .log_err();
679 }
680
681 // Keep presenting the current scene for 1 extra second since the
682 // last input to prevent the display from underclocking the refresh rate.
683 let needs_present = needs_present.get()
684 || (active.get()
685 && last_input_timestamp.get().elapsed() < Duration::from_secs(1));
686
687 if dirty.get() {
688 measure("frame duration", || {
689 handle
690 .update(&mut cx, |_, cx| {
691 cx.draw();
692 cx.present();
693 })
694 .log_err();
695 })
696 } else if needs_present {
697 handle.update(&mut cx, |_, cx| cx.present()).log_err();
698 }
699
700 handle
701 .update(&mut cx, |_, cx| {
702 cx.complete_frame();
703 })
704 .log_err();
705 }
706 }));
707 platform_window.on_resize(Box::new({
708 let mut cx = cx.to_async();
709 move |_, _| {
710 handle
711 .update(&mut cx, |_, cx| cx.bounds_changed())
712 .log_err();
713 }
714 }));
715 platform_window.on_moved(Box::new({
716 let mut cx = cx.to_async();
717 move || {
718 handle
719 .update(&mut cx, |_, cx| cx.bounds_changed())
720 .log_err();
721 }
722 }));
723 platform_window.on_appearance_changed(Box::new({
724 let mut cx = cx.to_async();
725 move || {
726 handle
727 .update(&mut cx, |_, cx| cx.appearance_changed())
728 .log_err();
729 }
730 }));
731 platform_window.on_active_status_change(Box::new({
732 let mut cx = cx.to_async();
733 move |active| {
734 handle
735 .update(&mut cx, |_, cx| {
736 cx.window.active.set(active);
737 cx.window
738 .activation_observers
739 .clone()
740 .retain(&(), |callback| callback(cx));
741 cx.refresh();
742 })
743 .log_err();
744 }
745 }));
746
747 platform_window.on_input({
748 let mut cx = cx.to_async();
749 Box::new(move |event| {
750 handle
751 .update(&mut cx, |_, cx| cx.dispatch_event(event))
752 .log_err()
753 .unwrap_or(DispatchEventResult::default())
754 })
755 });
756
757 if let Some(app_id) = app_id {
758 platform_window.set_app_id(&app_id);
759 }
760
761 Ok(Window {
762 handle,
763 removed: false,
764 platform_window,
765 display_id,
766 sprite_atlas,
767 text_system,
768 rem_size: px(16.),
769 rem_size_override_stack: SmallVec::new(),
770 viewport_size: content_size,
771 layout_engine: Some(TaffyLayoutEngine::new()),
772 root_view: None,
773 element_id_stack: SmallVec::default(),
774 text_style_stack: Vec::new(),
775 element_offset_stack: Vec::new(),
776 content_mask_stack: Vec::new(),
777 requested_autoscroll: None,
778 rendered_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
779 next_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
780 next_frame_callbacks,
781 next_hitbox_id: HitboxId::default(),
782 next_tooltip_id: TooltipId::default(),
783 tooltip_bounds: None,
784 dirty_views: FxHashSet::default(),
785 focus_handles: Arc::new(RwLock::new(SlotMap::with_key())),
786 focus_listeners: SubscriberSet::new(),
787 focus_lost_listeners: SubscriberSet::new(),
788 default_prevented: true,
789 mouse_position,
790 mouse_hit_test: HitTest::default(),
791 modifiers,
792 scale_factor,
793 bounds_observers: SubscriberSet::new(),
794 appearance,
795 appearance_observers: SubscriberSet::new(),
796 active,
797 dirty,
798 needs_present,
799 last_input_timestamp,
800 refreshing: false,
801 draw_phase: DrawPhase::None,
802 activation_observers: SubscriberSet::new(),
803 focus: None,
804 focus_enabled: true,
805 pending_input: None,
806 prompt: None,
807 })
808 }
809 fn new_focus_listener(
810 &mut self,
811 value: AnyWindowFocusListener,
812 ) -> (Subscription, impl FnOnce()) {
813 self.focus_listeners.insert((), value)
814 }
815}
816
817#[derive(Clone, Debug, Default, PartialEq, Eq)]
818pub(crate) struct DispatchEventResult {
819 pub propagate: bool,
820 pub default_prevented: bool,
821}
822
823/// Indicates which region of the window is visible. Content falling outside of this mask will not be
824/// rendered. Currently, only rectangular content masks are supported, but we give the mask its own type
825/// to leave room to support more complex shapes in the future.
826#[derive(Clone, Debug, Default, PartialEq, Eq)]
827#[repr(C)]
828pub struct ContentMask<P: Clone + Default + Debug> {
829 /// The bounds
830 pub bounds: Bounds<P>,
831}
832
833impl ContentMask<Pixels> {
834 /// Scale the content mask's pixel units by the given scaling factor.
835 pub fn scale(&self, factor: f32) -> ContentMask<ScaledPixels> {
836 ContentMask {
837 bounds: self.bounds.scale(factor),
838 }
839 }
840
841 /// Intersect the content mask with the given content mask.
842 pub fn intersect(&self, other: &Self) -> Self {
843 let bounds = self.bounds.intersect(&other.bounds);
844 ContentMask { bounds }
845 }
846}
847
848/// Provides access to application state in the context of a single window. Derefs
849/// to an [`AppContext`], so you can also pass a [`WindowContext`] to any method that takes
850/// an [`AppContext`] and call any [`AppContext`] methods.
851pub struct WindowContext<'a> {
852 pub(crate) app: &'a mut AppContext,
853 pub(crate) window: &'a mut Window,
854}
855
856impl<'a> WindowContext<'a> {
857 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window) -> Self {
858 Self { app, window }
859 }
860
861 /// Obtain a handle to the window that belongs to this context.
862 pub fn window_handle(&self) -> AnyWindowHandle {
863 self.window.handle
864 }
865
866 /// Mark the window as dirty, scheduling it to be redrawn on the next frame.
867 pub fn refresh(&mut self) {
868 if self.window.draw_phase == DrawPhase::None {
869 self.window.refreshing = true;
870 self.window.dirty.set(true);
871 }
872 }
873
874 /// Indicate that this view has changed, which will invoke any observers and also mark the window as dirty.
875 /// If this view or any of its ancestors are *cached*, notifying it will cause it or its ancestors to be redrawn.
876 pub fn notify(&mut self, view_id: EntityId) {
877 for view_id in self
878 .window
879 .rendered_frame
880 .dispatch_tree
881 .view_path(view_id)
882 .into_iter()
883 .rev()
884 {
885 if !self.window.dirty_views.insert(view_id) {
886 break;
887 }
888 }
889
890 if self.window.draw_phase == DrawPhase::None {
891 self.window.dirty.set(true);
892 self.app.push_effect(Effect::Notify { emitter: view_id });
893 }
894 }
895
896 /// Close this window.
897 pub fn remove_window(&mut self) {
898 self.window.removed = true;
899 }
900
901 /// Obtain a new [`FocusHandle`], which allows you to track and manipulate the keyboard focus
902 /// for elements rendered within this window.
903 pub fn focus_handle(&mut self) -> FocusHandle {
904 FocusHandle::new(&self.window.focus_handles)
905 }
906
907 /// Obtain the currently focused [`FocusHandle`]. If no elements are focused, returns `None`.
908 pub fn focused(&self) -> Option<FocusHandle> {
909 self.window
910 .focus
911 .and_then(|id| FocusHandle::for_id(id, &self.window.focus_handles))
912 }
913
914 /// Move focus to the element associated with the given [`FocusHandle`].
915 pub fn focus(&mut self, handle: &FocusHandle) {
916 if !self.window.focus_enabled || self.window.focus == Some(handle.id) {
917 return;
918 }
919
920 self.window.focus = Some(handle.id);
921 self.window
922 .rendered_frame
923 .dispatch_tree
924 .clear_pending_keystrokes();
925 self.refresh();
926 }
927
928 /// Remove focus from all elements within this context's window.
929 pub fn blur(&mut self) {
930 if !self.window.focus_enabled {
931 return;
932 }
933
934 self.window.focus = None;
935 self.refresh();
936 }
937
938 /// Blur the window and don't allow anything in it to be focused again.
939 pub fn disable_focus(&mut self) {
940 self.blur();
941 self.window.focus_enabled = false;
942 }
943
944 /// Accessor for the text system.
945 pub fn text_system(&self) -> &Arc<WindowTextSystem> {
946 &self.window.text_system
947 }
948
949 /// The current text style. Which is composed of all the style refinements provided to `with_text_style`.
950 pub fn text_style(&self) -> TextStyle {
951 let mut style = TextStyle::default();
952 for refinement in &self.window.text_style_stack {
953 style.refine(refinement);
954 }
955 style
956 }
957
958 /// Check if the platform window is maximized
959 /// On some platforms (namely Windows) this is different than the bounds being the size of the display
960 pub fn is_maximized(&self) -> bool {
961 self.window.platform_window.is_maximized()
962 }
963
964 /// Return the `WindowBounds` to indicate that how a window should be opened
965 /// after it has been closed
966 pub fn window_bounds(&self) -> WindowBounds {
967 self.window.platform_window.window_bounds()
968 }
969
970 /// Dispatch the given action on the currently focused element.
971 pub fn dispatch_action(&mut self, action: Box<dyn Action>) {
972 let focus_handle = self.focused();
973
974 let window = self.window.handle;
975 self.app.defer(move |cx| {
976 window
977 .update(cx, |_, cx| {
978 let node_id = focus_handle
979 .and_then(|handle| {
980 cx.window
981 .rendered_frame
982 .dispatch_tree
983 .focusable_node_id(handle.id)
984 })
985 .unwrap_or_else(|| cx.window.rendered_frame.dispatch_tree.root_node_id());
986
987 cx.dispatch_action_on_node(node_id, action.as_ref());
988 })
989 .log_err();
990 })
991 }
992
993 pub(crate) fn dispatch_keystroke_observers(
994 &mut self,
995 event: &dyn Any,
996 action: Option<Box<dyn Action>>,
997 ) {
998 let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() else {
999 return;
1000 };
1001
1002 self.keystroke_observers
1003 .clone()
1004 .retain(&(), move |callback| {
1005 (callback)(
1006 &KeystrokeEvent {
1007 keystroke: key_down_event.keystroke.clone(),
1008 action: action.as_ref().map(|action| action.boxed_clone()),
1009 },
1010 self,
1011 );
1012 true
1013 });
1014 }
1015
1016 pub(crate) fn clear_pending_keystrokes(&mut self) {
1017 self.window
1018 .rendered_frame
1019 .dispatch_tree
1020 .clear_pending_keystrokes();
1021 self.window
1022 .next_frame
1023 .dispatch_tree
1024 .clear_pending_keystrokes();
1025 }
1026
1027 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
1028 /// that are currently on the stack to be returned to the app.
1029 pub fn defer(&mut self, f: impl FnOnce(&mut WindowContext) + 'static) {
1030 let handle = self.window.handle;
1031 self.app.defer(move |cx| {
1032 handle.update(cx, |_, cx| f(cx)).ok();
1033 });
1034 }
1035
1036 /// Subscribe to events emitted by a model or view.
1037 /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
1038 /// 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.
1039 pub fn observe<E, T>(
1040 &mut self,
1041 entity: &E,
1042 mut on_notify: impl FnMut(E, &mut WindowContext<'_>) + 'static,
1043 ) -> Subscription
1044 where
1045 E: Entity<T>,
1046 {
1047 let entity_id = entity.entity_id();
1048 let entity = entity.downgrade();
1049 let window_handle = self.window.handle;
1050 self.app.new_observer(
1051 entity_id,
1052 Box::new(move |cx| {
1053 window_handle
1054 .update(cx, |_, cx| {
1055 if let Some(handle) = E::upgrade_from(&entity) {
1056 on_notify(handle, cx);
1057 true
1058 } else {
1059 false
1060 }
1061 })
1062 .unwrap_or(false)
1063 }),
1064 )
1065 }
1066
1067 /// Subscribe to events emitted by a model or view.
1068 /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
1069 /// 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.
1070 pub fn subscribe<Emitter, E, Evt>(
1071 &mut self,
1072 entity: &E,
1073 mut on_event: impl FnMut(E, &Evt, &mut WindowContext<'_>) + 'static,
1074 ) -> Subscription
1075 where
1076 Emitter: EventEmitter<Evt>,
1077 E: Entity<Emitter>,
1078 Evt: 'static,
1079 {
1080 let entity_id = entity.entity_id();
1081 let entity = entity.downgrade();
1082 let window_handle = self.window.handle;
1083 self.app.new_subscription(
1084 entity_id,
1085 (
1086 TypeId::of::<Evt>(),
1087 Box::new(move |event, cx| {
1088 window_handle
1089 .update(cx, |_, cx| {
1090 if let Some(handle) = E::upgrade_from(&entity) {
1091 let event = event.downcast_ref().expect("invalid event type");
1092 on_event(handle, event, cx);
1093 true
1094 } else {
1095 false
1096 }
1097 })
1098 .unwrap_or(false)
1099 }),
1100 ),
1101 )
1102 }
1103
1104 /// Creates an [`AsyncWindowContext`], which has a static lifetime and can be held across
1105 /// await points in async code.
1106 pub fn to_async(&self) -> AsyncWindowContext {
1107 AsyncWindowContext::new(self.app.to_async(), self.window.handle)
1108 }
1109
1110 /// Schedule the given closure to be run directly after the current frame is rendered.
1111 pub fn on_next_frame(&mut self, callback: impl FnOnce(&mut WindowContext) + 'static) {
1112 RefCell::borrow_mut(&self.window.next_frame_callbacks).push(Box::new(callback));
1113 }
1114
1115 /// Spawn the future returned by the given closure on the application thread pool.
1116 /// The closure is provided a handle to the current window and an `AsyncWindowContext` for
1117 /// use within your future.
1118 pub fn spawn<Fut, R>(&mut self, f: impl FnOnce(AsyncWindowContext) -> Fut) -> Task<R>
1119 where
1120 R: 'static,
1121 Fut: Future<Output = R> + 'static,
1122 {
1123 self.app
1124 .spawn(|app| f(AsyncWindowContext::new(app, self.window.handle)))
1125 }
1126
1127 fn bounds_changed(&mut self) {
1128 self.window.scale_factor = self.window.platform_window.scale_factor();
1129 self.window.viewport_size = self.window.platform_window.content_size();
1130 self.window.display_id = self
1131 .window
1132 .platform_window
1133 .display()
1134 .map(|display| display.id());
1135
1136 self.refresh();
1137
1138 self.window
1139 .bounds_observers
1140 .clone()
1141 .retain(&(), |callback| callback(self));
1142 }
1143
1144 /// Returns the bounds of the current window in the global coordinate space, which could span across multiple displays.
1145 pub fn bounds(&self) -> Bounds<Pixels> {
1146 self.window.platform_window.bounds()
1147 }
1148
1149 /// Returns whether or not the window is currently fullscreen
1150 pub fn is_fullscreen(&self) -> bool {
1151 self.window.platform_window.is_fullscreen()
1152 }
1153
1154 fn appearance_changed(&mut self) {
1155 self.window.appearance = self.window.platform_window.appearance();
1156
1157 self.window
1158 .appearance_observers
1159 .clone()
1160 .retain(&(), |callback| callback(self));
1161 }
1162
1163 /// Returns the appearance of the current window.
1164 pub fn appearance(&self) -> WindowAppearance {
1165 self.window.appearance
1166 }
1167
1168 /// Returns the size of the drawable area within the window.
1169 pub fn viewport_size(&self) -> Size<Pixels> {
1170 self.window.viewport_size
1171 }
1172
1173 /// Returns whether this window is focused by the operating system (receiving key events).
1174 pub fn is_window_active(&self) -> bool {
1175 self.window.active.get()
1176 }
1177
1178 /// Toggle zoom on the window.
1179 pub fn zoom_window(&self) {
1180 self.window.platform_window.zoom();
1181 }
1182
1183 /// Opens the native title bar context menu, useful when implementing client side decorations (Wayland and X11)
1184 pub fn show_window_menu(&self, position: Point<Pixels>) {
1185 self.window.platform_window.show_window_menu(position)
1186 }
1187
1188 /// Tells the compositor to take control of window movement (Wayland and X11)
1189 ///
1190 /// Events may not be received during a move operation.
1191 pub fn start_system_move(&self) {
1192 self.window.platform_window.start_system_move()
1193 }
1194
1195 /// Returns whether the title bar window controls need to be rendered by the application (Wayland and X11)
1196 pub fn should_render_window_controls(&self) -> bool {
1197 self.window.platform_window.should_render_window_controls()
1198 }
1199
1200 /// Updates the window's title at the platform level.
1201 pub fn set_window_title(&mut self, title: &str) {
1202 self.window.platform_window.set_title(title);
1203 }
1204
1205 /// Sets the application identifier.
1206 pub fn set_app_id(&mut self, app_id: &str) {
1207 self.window.platform_window.set_app_id(app_id);
1208 }
1209
1210 /// Sets the window background appearance.
1211 pub fn set_background_appearance(&mut self, background_appearance: WindowBackgroundAppearance) {
1212 self.window
1213 .platform_window
1214 .set_background_appearance(background_appearance);
1215 }
1216
1217 /// Mark the window as dirty at the platform level.
1218 pub fn set_window_edited(&mut self, edited: bool) {
1219 self.window.platform_window.set_edited(edited);
1220 }
1221
1222 /// Determine the display on which the window is visible.
1223 pub fn display(&self) -> Option<Rc<dyn PlatformDisplay>> {
1224 self.platform
1225 .displays()
1226 .into_iter()
1227 .find(|display| Some(display.id()) == self.window.display_id)
1228 }
1229
1230 /// Show the platform character palette.
1231 pub fn show_character_palette(&self) {
1232 self.window.platform_window.show_character_palette();
1233 }
1234
1235 /// The scale factor of the display associated with the window. For example, it could
1236 /// return 2.0 for a "retina" display, indicating that each logical pixel should actually
1237 /// be rendered as two pixels on screen.
1238 pub fn scale_factor(&self) -> f32 {
1239 self.window.scale_factor
1240 }
1241
1242 /// The size of an em for the base font of the application. Adjusting this value allows the
1243 /// UI to scale, just like zooming a web page.
1244 pub fn rem_size(&self) -> Pixels {
1245 self.window
1246 .rem_size_override_stack
1247 .last()
1248 .copied()
1249 .unwrap_or(self.window.rem_size)
1250 }
1251
1252 /// Sets the size of an em for the base font of the application. Adjusting this value allows the
1253 /// UI to scale, just like zooming a web page.
1254 pub fn set_rem_size(&mut self, rem_size: impl Into<Pixels>) {
1255 self.window.rem_size = rem_size.into();
1256 }
1257
1258 /// Executes the provided function with the specified rem size.
1259 ///
1260 /// This method must only be called as part of element drawing.
1261 pub fn with_rem_size<F, R>(&mut self, rem_size: Option<impl Into<Pixels>>, f: F) -> R
1262 where
1263 F: FnOnce(&mut Self) -> R,
1264 {
1265 debug_assert!(
1266 matches!(
1267 self.window.draw_phase,
1268 DrawPhase::Prepaint | DrawPhase::Paint
1269 ),
1270 "this method can only be called during request_layout, prepaint, or paint"
1271 );
1272
1273 if let Some(rem_size) = rem_size {
1274 self.window.rem_size_override_stack.push(rem_size.into());
1275 let result = f(self);
1276 self.window.rem_size_override_stack.pop();
1277 result
1278 } else {
1279 f(self)
1280 }
1281 }
1282
1283 /// The line height associated with the current text style.
1284 pub fn line_height(&self) -> Pixels {
1285 let rem_size = self.rem_size();
1286 let text_style = self.text_style();
1287 text_style
1288 .line_height
1289 .to_pixels(text_style.font_size, rem_size)
1290 }
1291
1292 /// Call to prevent the default action of an event. Currently only used to prevent
1293 /// parent elements from becoming focused on mouse down.
1294 pub fn prevent_default(&mut self) {
1295 self.window.default_prevented = true;
1296 }
1297
1298 /// Obtain whether default has been prevented for the event currently being dispatched.
1299 pub fn default_prevented(&self) -> bool {
1300 self.window.default_prevented
1301 }
1302
1303 /// Determine whether the given action is available along the dispatch path to the currently focused element.
1304 pub fn is_action_available(&self, action: &dyn Action) -> bool {
1305 let target = self
1306 .focused()
1307 .and_then(|focused_handle| {
1308 self.window
1309 .rendered_frame
1310 .dispatch_tree
1311 .focusable_node_id(focused_handle.id)
1312 })
1313 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
1314 self.window
1315 .rendered_frame
1316 .dispatch_tree
1317 .is_action_available(action, target)
1318 }
1319
1320 /// The position of the mouse relative to the window.
1321 pub fn mouse_position(&self) -> Point<Pixels> {
1322 self.window.mouse_position
1323 }
1324
1325 /// The current state of the keyboard's modifiers
1326 pub fn modifiers(&self) -> Modifiers {
1327 self.window.modifiers
1328 }
1329
1330 fn complete_frame(&self) {
1331 self.window.platform_window.completed_frame();
1332 }
1333
1334 /// Produces a new frame and assigns it to `rendered_frame`. To actually show
1335 /// the contents of the new [Scene], use [present].
1336 #[profiling::function]
1337 pub fn draw(&mut self) {
1338 self.window.dirty.set(false);
1339 self.window.requested_autoscroll = None;
1340
1341 // Restore the previously-used input handler.
1342 if let Some(input_handler) = self.window.platform_window.take_input_handler() {
1343 self.window
1344 .rendered_frame
1345 .input_handlers
1346 .push(Some(input_handler));
1347 }
1348
1349 self.draw_roots();
1350 self.window.dirty_views.clear();
1351
1352 self.window
1353 .next_frame
1354 .dispatch_tree
1355 .preserve_pending_keystrokes(
1356 &mut self.window.rendered_frame.dispatch_tree,
1357 self.window.focus,
1358 );
1359 self.window.next_frame.focus = self.window.focus;
1360 self.window.next_frame.window_active = self.window.active.get();
1361
1362 // Register requested input handler with the platform window.
1363 if let Some(input_handler) = self.window.next_frame.input_handlers.pop() {
1364 self.window
1365 .platform_window
1366 .set_input_handler(input_handler.unwrap());
1367 }
1368
1369 self.window.layout_engine.as_mut().unwrap().clear();
1370 self.text_system().finish_frame();
1371 self.window
1372 .next_frame
1373 .finish(&mut self.window.rendered_frame);
1374 ELEMENT_ARENA.with_borrow_mut(|element_arena| {
1375 let percentage = (element_arena.len() as f32 / element_arena.capacity() as f32) * 100.;
1376 if percentage >= 80. {
1377 log::warn!("elevated element arena occupation: {}.", percentage);
1378 }
1379 element_arena.clear();
1380 });
1381
1382 self.window.draw_phase = DrawPhase::Focus;
1383 let previous_focus_path = self.window.rendered_frame.focus_path();
1384 let previous_window_active = self.window.rendered_frame.window_active;
1385 mem::swap(&mut self.window.rendered_frame, &mut self.window.next_frame);
1386 self.window.next_frame.clear();
1387 let current_focus_path = self.window.rendered_frame.focus_path();
1388 let current_window_active = self.window.rendered_frame.window_active;
1389
1390 if previous_focus_path != current_focus_path
1391 || previous_window_active != current_window_active
1392 {
1393 if !previous_focus_path.is_empty() && current_focus_path.is_empty() {
1394 self.window
1395 .focus_lost_listeners
1396 .clone()
1397 .retain(&(), |listener| listener(self));
1398 }
1399
1400 let event = FocusEvent {
1401 previous_focus_path: if previous_window_active {
1402 previous_focus_path
1403 } else {
1404 Default::default()
1405 },
1406 current_focus_path: if current_window_active {
1407 current_focus_path
1408 } else {
1409 Default::default()
1410 },
1411 };
1412 self.window
1413 .focus_listeners
1414 .clone()
1415 .retain(&(), |listener| listener(&event, self));
1416 }
1417
1418 self.reset_cursor_style();
1419 self.window.refreshing = false;
1420 self.window.draw_phase = DrawPhase::None;
1421 self.window.needs_present.set(true);
1422 }
1423
1424 #[profiling::function]
1425 fn present(&self) {
1426 self.window
1427 .platform_window
1428 .draw(&self.window.rendered_frame.scene);
1429 self.window.needs_present.set(false);
1430 profiling::finish_frame!();
1431 }
1432
1433 fn draw_roots(&mut self) {
1434 self.window.draw_phase = DrawPhase::Prepaint;
1435 self.window.tooltip_bounds.take();
1436
1437 // Layout all root elements.
1438 let mut root_element = self.window.root_view.as_ref().unwrap().clone().into_any();
1439 root_element.prepaint_as_root(Point::default(), self.window.viewport_size.into(), self);
1440
1441 let mut sorted_deferred_draws =
1442 (0..self.window.next_frame.deferred_draws.len()).collect::<SmallVec<[_; 8]>>();
1443 sorted_deferred_draws.sort_by_key(|ix| self.window.next_frame.deferred_draws[*ix].priority);
1444 self.prepaint_deferred_draws(&sorted_deferred_draws);
1445
1446 let mut prompt_element = None;
1447 let mut active_drag_element = None;
1448 let mut tooltip_element = None;
1449 if let Some(prompt) = self.window.prompt.take() {
1450 let mut element = prompt.view.any_view().into_any();
1451 element.prepaint_as_root(Point::default(), self.window.viewport_size.into(), self);
1452 prompt_element = Some(element);
1453 self.window.prompt = Some(prompt);
1454 } else if let Some(active_drag) = self.app.active_drag.take() {
1455 let mut element = active_drag.view.clone().into_any();
1456 let offset = self.mouse_position() - active_drag.cursor_offset;
1457 element.prepaint_as_root(offset, AvailableSpace::min_size(), self);
1458 active_drag_element = Some(element);
1459 self.app.active_drag = Some(active_drag);
1460 } else {
1461 tooltip_element = self.prepaint_tooltip();
1462 }
1463
1464 self.window.mouse_hit_test = self.window.next_frame.hit_test(self.window.mouse_position);
1465
1466 // Now actually paint the elements.
1467 self.window.draw_phase = DrawPhase::Paint;
1468 root_element.paint(self);
1469
1470 self.paint_deferred_draws(&sorted_deferred_draws);
1471
1472 if let Some(mut prompt_element) = prompt_element {
1473 prompt_element.paint(self)
1474 } else if let Some(mut drag_element) = active_drag_element {
1475 drag_element.paint(self);
1476 } else if let Some(mut tooltip_element) = tooltip_element {
1477 tooltip_element.paint(self);
1478 }
1479 }
1480
1481 fn prepaint_tooltip(&mut self) -> Option<AnyElement> {
1482 let tooltip_request = self.window.next_frame.tooltip_requests.last().cloned()?;
1483 let tooltip_request = tooltip_request.unwrap();
1484 let mut element = tooltip_request.tooltip.view.clone().into_any();
1485 let mouse_position = tooltip_request.tooltip.mouse_position;
1486 let tooltip_size = element.layout_as_root(AvailableSpace::min_size(), self);
1487
1488 let mut tooltip_bounds = Bounds::new(mouse_position + point(px(1.), px(1.)), tooltip_size);
1489 let window_bounds = Bounds {
1490 origin: Point::default(),
1491 size: self.viewport_size(),
1492 };
1493
1494 if tooltip_bounds.right() > window_bounds.right() {
1495 let new_x = mouse_position.x - tooltip_bounds.size.width - px(1.);
1496 if new_x >= Pixels::ZERO {
1497 tooltip_bounds.origin.x = new_x;
1498 } else {
1499 tooltip_bounds.origin.x = cmp::max(
1500 Pixels::ZERO,
1501 tooltip_bounds.origin.x - tooltip_bounds.right() - window_bounds.right(),
1502 );
1503 }
1504 }
1505
1506 if tooltip_bounds.bottom() > window_bounds.bottom() {
1507 let new_y = mouse_position.y - tooltip_bounds.size.height - px(1.);
1508 if new_y >= Pixels::ZERO {
1509 tooltip_bounds.origin.y = new_y;
1510 } else {
1511 tooltip_bounds.origin.y = cmp::max(
1512 Pixels::ZERO,
1513 tooltip_bounds.origin.y - tooltip_bounds.bottom() - window_bounds.bottom(),
1514 );
1515 }
1516 }
1517
1518 self.with_absolute_element_offset(tooltip_bounds.origin, |cx| element.prepaint(cx));
1519
1520 self.window.tooltip_bounds = Some(TooltipBounds {
1521 id: tooltip_request.id,
1522 bounds: tooltip_bounds,
1523 });
1524 Some(element)
1525 }
1526
1527 fn prepaint_deferred_draws(&mut self, deferred_draw_indices: &[usize]) {
1528 assert_eq!(self.window.element_id_stack.len(), 0);
1529
1530 let mut deferred_draws = mem::take(&mut self.window.next_frame.deferred_draws);
1531 for deferred_draw_ix in deferred_draw_indices {
1532 let deferred_draw = &mut deferred_draws[*deferred_draw_ix];
1533 self.window
1534 .element_id_stack
1535 .clone_from(&deferred_draw.element_id_stack);
1536 self.window
1537 .text_style_stack
1538 .clone_from(&deferred_draw.text_style_stack);
1539 self.window
1540 .next_frame
1541 .dispatch_tree
1542 .set_active_node(deferred_draw.parent_node);
1543
1544 let prepaint_start = self.prepaint_index();
1545 if let Some(element) = deferred_draw.element.as_mut() {
1546 self.with_absolute_element_offset(deferred_draw.absolute_offset, |cx| {
1547 element.prepaint(cx)
1548 });
1549 } else {
1550 self.reuse_prepaint(deferred_draw.prepaint_range.clone());
1551 }
1552 let prepaint_end = self.prepaint_index();
1553 deferred_draw.prepaint_range = prepaint_start..prepaint_end;
1554 }
1555 assert_eq!(
1556 self.window.next_frame.deferred_draws.len(),
1557 0,
1558 "cannot call defer_draw during deferred drawing"
1559 );
1560 self.window.next_frame.deferred_draws = deferred_draws;
1561 self.window.element_id_stack.clear();
1562 self.window.text_style_stack.clear();
1563 }
1564
1565 fn paint_deferred_draws(&mut self, deferred_draw_indices: &[usize]) {
1566 assert_eq!(self.window.element_id_stack.len(), 0);
1567
1568 let mut deferred_draws = mem::take(&mut self.window.next_frame.deferred_draws);
1569 for deferred_draw_ix in deferred_draw_indices {
1570 let mut deferred_draw = &mut deferred_draws[*deferred_draw_ix];
1571 self.window
1572 .element_id_stack
1573 .clone_from(&deferred_draw.element_id_stack);
1574 self.window
1575 .next_frame
1576 .dispatch_tree
1577 .set_active_node(deferred_draw.parent_node);
1578
1579 let paint_start = self.paint_index();
1580 if let Some(element) = deferred_draw.element.as_mut() {
1581 element.paint(self);
1582 } else {
1583 self.reuse_paint(deferred_draw.paint_range.clone());
1584 }
1585 let paint_end = self.paint_index();
1586 deferred_draw.paint_range = paint_start..paint_end;
1587 }
1588 self.window.next_frame.deferred_draws = deferred_draws;
1589 self.window.element_id_stack.clear();
1590 }
1591
1592 pub(crate) fn prepaint_index(&self) -> PrepaintStateIndex {
1593 PrepaintStateIndex {
1594 hitboxes_index: self.window.next_frame.hitboxes.len(),
1595 tooltips_index: self.window.next_frame.tooltip_requests.len(),
1596 deferred_draws_index: self.window.next_frame.deferred_draws.len(),
1597 dispatch_tree_index: self.window.next_frame.dispatch_tree.len(),
1598 accessed_element_states_index: self.window.next_frame.accessed_element_states.len(),
1599 line_layout_index: self.window.text_system.layout_index(),
1600 }
1601 }
1602
1603 pub(crate) fn reuse_prepaint(&mut self, range: Range<PrepaintStateIndex>) {
1604 let window = &mut self.window;
1605 window.next_frame.hitboxes.extend(
1606 window.rendered_frame.hitboxes[range.start.hitboxes_index..range.end.hitboxes_index]
1607 .iter()
1608 .cloned(),
1609 );
1610 window.next_frame.tooltip_requests.extend(
1611 window.rendered_frame.tooltip_requests
1612 [range.start.tooltips_index..range.end.tooltips_index]
1613 .iter_mut()
1614 .map(|request| request.take()),
1615 );
1616 window.next_frame.accessed_element_states.extend(
1617 window.rendered_frame.accessed_element_states[range.start.accessed_element_states_index
1618 ..range.end.accessed_element_states_index]
1619 .iter()
1620 .map(|(id, type_id)| (GlobalElementId(id.0.clone()), *type_id)),
1621 );
1622 window
1623 .text_system
1624 .reuse_layouts(range.start.line_layout_index..range.end.line_layout_index);
1625
1626 let reused_subtree = window.next_frame.dispatch_tree.reuse_subtree(
1627 range.start.dispatch_tree_index..range.end.dispatch_tree_index,
1628 &mut window.rendered_frame.dispatch_tree,
1629 );
1630 window.next_frame.deferred_draws.extend(
1631 window.rendered_frame.deferred_draws
1632 [range.start.deferred_draws_index..range.end.deferred_draws_index]
1633 .iter()
1634 .map(|deferred_draw| DeferredDraw {
1635 parent_node: reused_subtree.refresh_node_id(deferred_draw.parent_node),
1636 element_id_stack: deferred_draw.element_id_stack.clone(),
1637 text_style_stack: deferred_draw.text_style_stack.clone(),
1638 priority: deferred_draw.priority,
1639 element: None,
1640 absolute_offset: deferred_draw.absolute_offset,
1641 prepaint_range: deferred_draw.prepaint_range.clone(),
1642 paint_range: deferred_draw.paint_range.clone(),
1643 }),
1644 );
1645 }
1646
1647 pub(crate) fn paint_index(&self) -> PaintIndex {
1648 PaintIndex {
1649 scene_index: self.window.next_frame.scene.len(),
1650 mouse_listeners_index: self.window.next_frame.mouse_listeners.len(),
1651 input_handlers_index: self.window.next_frame.input_handlers.len(),
1652 cursor_styles_index: self.window.next_frame.cursor_styles.len(),
1653 accessed_element_states_index: self.window.next_frame.accessed_element_states.len(),
1654 line_layout_index: self.window.text_system.layout_index(),
1655 }
1656 }
1657
1658 pub(crate) fn reuse_paint(&mut self, range: Range<PaintIndex>) {
1659 let window = &mut self.window;
1660
1661 window.next_frame.cursor_styles.extend(
1662 window.rendered_frame.cursor_styles
1663 [range.start.cursor_styles_index..range.end.cursor_styles_index]
1664 .iter()
1665 .cloned(),
1666 );
1667 window.next_frame.input_handlers.extend(
1668 window.rendered_frame.input_handlers
1669 [range.start.input_handlers_index..range.end.input_handlers_index]
1670 .iter_mut()
1671 .map(|handler| handler.take()),
1672 );
1673 window.next_frame.mouse_listeners.extend(
1674 window.rendered_frame.mouse_listeners
1675 [range.start.mouse_listeners_index..range.end.mouse_listeners_index]
1676 .iter_mut()
1677 .map(|listener| listener.take()),
1678 );
1679 window.next_frame.accessed_element_states.extend(
1680 window.rendered_frame.accessed_element_states[range.start.accessed_element_states_index
1681 ..range.end.accessed_element_states_index]
1682 .iter()
1683 .map(|(id, type_id)| (GlobalElementId(id.0.clone()), *type_id)),
1684 );
1685 window
1686 .text_system
1687 .reuse_layouts(range.start.line_layout_index..range.end.line_layout_index);
1688 window.next_frame.scene.replay(
1689 range.start.scene_index..range.end.scene_index,
1690 &window.rendered_frame.scene,
1691 );
1692 }
1693
1694 /// Push a text style onto the stack, and call a function with that style active.
1695 /// Use [`AppContext::text_style`] to get the current, combined text style. This method
1696 /// should only be called as part of element drawing.
1697 pub fn with_text_style<F, R>(&mut self, style: Option<TextStyleRefinement>, f: F) -> R
1698 where
1699 F: FnOnce(&mut Self) -> R,
1700 {
1701 debug_assert!(
1702 matches!(
1703 self.window.draw_phase,
1704 DrawPhase::Prepaint | DrawPhase::Paint
1705 ),
1706 "this method can only be called during request_layout, prepaint, or paint"
1707 );
1708 if let Some(style) = style {
1709 self.window.text_style_stack.push(style);
1710 let result = f(self);
1711 self.window.text_style_stack.pop();
1712 result
1713 } else {
1714 f(self)
1715 }
1716 }
1717
1718 /// Updates the cursor style at the platform level. This method should only be called
1719 /// during the prepaint phase of element drawing.
1720 pub fn set_cursor_style(&mut self, style: CursorStyle, hitbox: &Hitbox) {
1721 debug_assert_eq!(
1722 self.window.draw_phase,
1723 DrawPhase::Paint,
1724 "this method can only be called during paint"
1725 );
1726 self.window
1727 .next_frame
1728 .cursor_styles
1729 .push(CursorStyleRequest {
1730 hitbox_id: hitbox.id,
1731 style,
1732 });
1733 }
1734
1735 /// Sets a tooltip to be rendered for the upcoming frame. This method should only be called
1736 /// during the paint phase of element drawing.
1737 pub fn set_tooltip(&mut self, tooltip: AnyTooltip) -> TooltipId {
1738 debug_assert_eq!(
1739 self.window.draw_phase,
1740 DrawPhase::Prepaint,
1741 "this method can only be called during prepaint"
1742 );
1743 let id = TooltipId(post_inc(&mut self.window.next_tooltip_id.0));
1744 self.window
1745 .next_frame
1746 .tooltip_requests
1747 .push(Some(TooltipRequest { id, tooltip }));
1748 id
1749 }
1750
1751 /// Invoke the given function with the given content mask after intersecting it
1752 /// with the current mask. This method should only be called during element drawing.
1753 pub fn with_content_mask<R>(
1754 &mut self,
1755 mask: Option<ContentMask<Pixels>>,
1756 f: impl FnOnce(&mut Self) -> R,
1757 ) -> R {
1758 debug_assert!(
1759 matches!(
1760 self.window.draw_phase,
1761 DrawPhase::Prepaint | DrawPhase::Paint
1762 ),
1763 "this method can only be called during request_layout, prepaint, or paint"
1764 );
1765 if let Some(mask) = mask {
1766 let mask = mask.intersect(&self.content_mask());
1767 self.window_mut().content_mask_stack.push(mask);
1768 let result = f(self);
1769 self.window_mut().content_mask_stack.pop();
1770 result
1771 } else {
1772 f(self)
1773 }
1774 }
1775
1776 /// Updates the global element offset relative to the current offset. This is used to implement
1777 /// scrolling. This method should only be called during the prepaint phase of element drawing.
1778 pub fn with_element_offset<R>(
1779 &mut self,
1780 offset: Point<Pixels>,
1781 f: impl FnOnce(&mut Self) -> R,
1782 ) -> R {
1783 debug_assert_eq!(
1784 self.window.draw_phase,
1785 DrawPhase::Prepaint,
1786 "this method can only be called during request_layout, or prepaint"
1787 );
1788
1789 if offset.is_zero() {
1790 return f(self);
1791 };
1792
1793 let abs_offset = self.element_offset() + offset;
1794 self.with_absolute_element_offset(abs_offset, f)
1795 }
1796
1797 /// Updates the global element offset based on the given offset. This is used to implement
1798 /// drag handles and other manual painting of elements. This method should only be called during
1799 /// the prepaint phase of element drawing.
1800 pub fn with_absolute_element_offset<R>(
1801 &mut self,
1802 offset: Point<Pixels>,
1803 f: impl FnOnce(&mut Self) -> R,
1804 ) -> R {
1805 debug_assert_eq!(
1806 self.window.draw_phase,
1807 DrawPhase::Prepaint,
1808 "this method can only be called during request_layout, or prepaint"
1809 );
1810 self.window_mut().element_offset_stack.push(offset);
1811 let result = f(self);
1812 self.window_mut().element_offset_stack.pop();
1813 result
1814 }
1815
1816 /// Perform prepaint on child elements in a "retryable" manner, so that any side effects
1817 /// of prepaints can be discarded before prepainting again. This is used to support autoscroll
1818 /// where we need to prepaint children to detect the autoscroll bounds, then adjust the
1819 /// element offset and prepaint again. See [`List`] for an example. This method should only be
1820 /// called during the prepaint phase of element drawing.
1821 pub fn transact<T, U>(&mut self, f: impl FnOnce(&mut Self) -> Result<T, U>) -> Result<T, U> {
1822 debug_assert_eq!(
1823 self.window.draw_phase,
1824 DrawPhase::Prepaint,
1825 "this method can only be called during prepaint"
1826 );
1827 let index = self.prepaint_index();
1828 let result = f(self);
1829 if result.is_err() {
1830 self.window
1831 .next_frame
1832 .hitboxes
1833 .truncate(index.hitboxes_index);
1834 self.window
1835 .next_frame
1836 .tooltip_requests
1837 .truncate(index.tooltips_index);
1838 self.window
1839 .next_frame
1840 .deferred_draws
1841 .truncate(index.deferred_draws_index);
1842 self.window
1843 .next_frame
1844 .dispatch_tree
1845 .truncate(index.dispatch_tree_index);
1846 self.window
1847 .next_frame
1848 .accessed_element_states
1849 .truncate(index.accessed_element_states_index);
1850 self.window
1851 .text_system
1852 .truncate_layouts(index.line_layout_index);
1853 }
1854 result
1855 }
1856
1857 /// When you call this method during [`prepaint`], containing elements will attempt to
1858 /// scroll to cause the specified bounds to become visible. When they decide to autoscroll, they will call
1859 /// [`prepaint`] again with a new set of bounds. See [`List`] for an example of an element
1860 /// that supports this method being called on the elements it contains. This method should only be
1861 /// called during the prepaint phase of element drawing.
1862 pub fn request_autoscroll(&mut self, bounds: Bounds<Pixels>) {
1863 debug_assert_eq!(
1864 self.window.draw_phase,
1865 DrawPhase::Prepaint,
1866 "this method can only be called during prepaint"
1867 );
1868 self.window.requested_autoscroll = Some(bounds);
1869 }
1870
1871 /// This method can be called from a containing element such as [`List`] to support the autoscroll behavior
1872 /// described in [`request_autoscroll`].
1873 pub fn take_autoscroll(&mut self) -> Option<Bounds<Pixels>> {
1874 debug_assert_eq!(
1875 self.window.draw_phase,
1876 DrawPhase::Prepaint,
1877 "this method can only be called during prepaint"
1878 );
1879 self.window.requested_autoscroll.take()
1880 }
1881
1882 /// Remove an asset from GPUI's cache
1883 pub fn remove_cached_asset<A: Asset + 'static>(
1884 &mut self,
1885 source: &A::Source,
1886 ) -> Option<A::Output> {
1887 self.asset_cache.remove::<A>(source)
1888 }
1889
1890 /// Asynchronously load an asset, if the asset hasn't finished loading this will return None.
1891 /// Your view will be re-drawn once the asset has finished loading.
1892 ///
1893 /// Note that the multiple calls to this method will only result in one `Asset::load` call.
1894 /// The results of that call will be cached, and returned on subsequent uses of this API.
1895 ///
1896 /// Use [Self::remove_cached_asset] to reload your asset.
1897 pub fn use_cached_asset<A: Asset + 'static>(
1898 &mut self,
1899 source: &A::Source,
1900 ) -> Option<A::Output> {
1901 self.asset_cache.get::<A>(source).or_else(|| {
1902 if let Some(asset) = self.use_asset::<A>(source) {
1903 self.asset_cache
1904 .insert::<A>(source.to_owned(), asset.clone());
1905 Some(asset)
1906 } else {
1907 None
1908 }
1909 })
1910 }
1911
1912 /// Asynchronously load an asset, if the asset hasn't finished loading this will return None.
1913 /// Your view will be re-drawn once the asset has finished loading.
1914 ///
1915 /// Note that the multiple calls to this method will only result in one `Asset::load` call at a
1916 /// time.
1917 ///
1918 /// This asset will not be cached by default, see [Self::use_cached_asset]
1919 pub fn use_asset<A: Asset + 'static>(&mut self, source: &A::Source) -> Option<A::Output> {
1920 let asset_id = (TypeId::of::<A>(), hash(source));
1921 let mut is_first = false;
1922 let task = self
1923 .loading_assets
1924 .remove(&asset_id)
1925 .map(|boxed_task| *boxed_task.downcast::<Shared<Task<A::Output>>>().unwrap())
1926 .unwrap_or_else(|| {
1927 is_first = true;
1928 let future = A::load(source.clone(), self);
1929 let task = self.background_executor().spawn(future).shared();
1930 task
1931 });
1932
1933 task.clone().now_or_never().or_else(|| {
1934 if is_first {
1935 let parent_id = self.parent_view_id();
1936 self.spawn({
1937 let task = task.clone();
1938 |mut cx| async move {
1939 task.await;
1940
1941 cx.on_next_frame(move |cx| {
1942 if let Some(parent_id) = parent_id {
1943 cx.notify(parent_id)
1944 } else {
1945 cx.refresh()
1946 }
1947 });
1948 }
1949 })
1950 .detach();
1951 }
1952
1953 self.loading_assets.insert(asset_id, Box::new(task));
1954
1955 None
1956 })
1957 }
1958
1959 /// Obtain the current element offset. This method should only be called during the
1960 /// prepaint phase of element drawing.
1961 pub fn element_offset(&self) -> Point<Pixels> {
1962 debug_assert_eq!(
1963 self.window.draw_phase,
1964 DrawPhase::Prepaint,
1965 "this method can only be called during prepaint"
1966 );
1967 self.window()
1968 .element_offset_stack
1969 .last()
1970 .copied()
1971 .unwrap_or_default()
1972 }
1973
1974 /// Obtain the current content mask. This method should only be called during element drawing.
1975 pub fn content_mask(&self) -> ContentMask<Pixels> {
1976 debug_assert!(
1977 matches!(
1978 self.window.draw_phase,
1979 DrawPhase::Prepaint | DrawPhase::Paint
1980 ),
1981 "this method can only be called during prepaint, or paint"
1982 );
1983 self.window()
1984 .content_mask_stack
1985 .last()
1986 .cloned()
1987 .unwrap_or_else(|| ContentMask {
1988 bounds: Bounds {
1989 origin: Point::default(),
1990 size: self.window().viewport_size,
1991 },
1992 })
1993 }
1994
1995 /// Provide elements in the called function with a new namespace in which their identiers must be unique.
1996 /// This can be used within a custom element to distinguish multiple sets of child elements.
1997 pub fn with_element_namespace<R>(
1998 &mut self,
1999 element_id: impl Into<ElementId>,
2000 f: impl FnOnce(&mut Self) -> R,
2001 ) -> R {
2002 self.window.element_id_stack.push(element_id.into());
2003 let result = f(self);
2004 self.window.element_id_stack.pop();
2005 result
2006 }
2007
2008 /// Updates or initializes state for an element with the given id that lives across multiple
2009 /// frames. If an element with this ID existed in the rendered frame, its state will be passed
2010 /// to the given closure. The state returned by the closure will be stored so it can be referenced
2011 /// when drawing the next frame. This method should only be called as part of element drawing.
2012 pub fn with_element_state<S, R>(
2013 &mut self,
2014 global_id: &GlobalElementId,
2015 f: impl FnOnce(Option<S>, &mut Self) -> (R, S),
2016 ) -> R
2017 where
2018 S: 'static,
2019 {
2020 debug_assert!(
2021 matches!(
2022 self.window.draw_phase,
2023 DrawPhase::Prepaint | DrawPhase::Paint
2024 ),
2025 "this method can only be called during request_layout, prepaint, or paint"
2026 );
2027
2028 let key = (GlobalElementId(global_id.0.clone()), TypeId::of::<S>());
2029 self.window
2030 .next_frame
2031 .accessed_element_states
2032 .push((GlobalElementId(key.0.clone()), TypeId::of::<S>()));
2033
2034 if let Some(any) = self
2035 .window
2036 .next_frame
2037 .element_states
2038 .remove(&key)
2039 .or_else(|| self.window.rendered_frame.element_states.remove(&key))
2040 {
2041 let ElementStateBox {
2042 inner,
2043 #[cfg(debug_assertions)]
2044 type_name,
2045 } = any;
2046 // Using the extra inner option to avoid needing to reallocate a new box.
2047 let mut state_box = inner
2048 .downcast::<Option<S>>()
2049 .map_err(|_| {
2050 #[cfg(debug_assertions)]
2051 {
2052 anyhow::anyhow!(
2053 "invalid element state type for id, requested {:?}, actual: {:?}",
2054 std::any::type_name::<S>(),
2055 type_name
2056 )
2057 }
2058
2059 #[cfg(not(debug_assertions))]
2060 {
2061 anyhow::anyhow!(
2062 "invalid element state type for id, requested {:?}",
2063 std::any::type_name::<S>(),
2064 )
2065 }
2066 })
2067 .unwrap();
2068
2069 let state = state_box.take().expect(
2070 "reentrant call to with_element_state for the same state type and element id",
2071 );
2072 let (result, state) = f(Some(state), self);
2073 state_box.replace(state);
2074 self.window.next_frame.element_states.insert(
2075 key,
2076 ElementStateBox {
2077 inner: state_box,
2078 #[cfg(debug_assertions)]
2079 type_name,
2080 },
2081 );
2082 result
2083 } else {
2084 let (result, state) = f(None, self);
2085 self.window.next_frame.element_states.insert(
2086 key,
2087 ElementStateBox {
2088 inner: Box::new(Some(state)),
2089 #[cfg(debug_assertions)]
2090 type_name: std::any::type_name::<S>(),
2091 },
2092 );
2093 result
2094 }
2095 }
2096
2097 /// A variant of `with_element_state` that allows the element's id to be optional. This is a convenience
2098 /// method for elements where the element id may or may not be assigned. Prefer using `with_element_state`
2099 /// when the element is guaranteed to have an id.
2100 pub fn with_optional_element_state<S, R>(
2101 &mut self,
2102 global_id: Option<&GlobalElementId>,
2103 f: impl FnOnce(Option<Option<S>>, &mut Self) -> (R, Option<S>),
2104 ) -> R
2105 where
2106 S: 'static,
2107 {
2108 debug_assert!(
2109 matches!(
2110 self.window.draw_phase,
2111 DrawPhase::Prepaint | DrawPhase::Paint
2112 ),
2113 "this method can only be called during request_layout, prepaint, or paint"
2114 );
2115
2116 if let Some(global_id) = global_id {
2117 self.with_element_state(global_id, |state, cx| {
2118 let (result, state) = f(Some(state), cx);
2119 let state =
2120 state.expect("you must return some state when you pass some element id");
2121 (result, state)
2122 })
2123 } else {
2124 let (result, state) = f(None, self);
2125 debug_assert!(
2126 state.is_none(),
2127 "you must not return an element state when passing None for the global id"
2128 );
2129 result
2130 }
2131 }
2132
2133 /// Defers the drawing of the given element, scheduling it to be painted on top of the currently-drawn tree
2134 /// at a later time. The `priority` parameter determines the drawing order relative to other deferred elements,
2135 /// with higher values being drawn on top.
2136 ///
2137 /// This method should only be called as part of the prepaint phase of element drawing.
2138 pub fn defer_draw(
2139 &mut self,
2140 element: AnyElement,
2141 absolute_offset: Point<Pixels>,
2142 priority: usize,
2143 ) {
2144 let window = &mut self.window;
2145 debug_assert_eq!(
2146 window.draw_phase,
2147 DrawPhase::Prepaint,
2148 "this method can only be called during request_layout or prepaint"
2149 );
2150 let parent_node = window.next_frame.dispatch_tree.active_node_id().unwrap();
2151 window.next_frame.deferred_draws.push(DeferredDraw {
2152 parent_node,
2153 element_id_stack: window.element_id_stack.clone(),
2154 text_style_stack: window.text_style_stack.clone(),
2155 priority,
2156 element: Some(element),
2157 absolute_offset,
2158 prepaint_range: PrepaintStateIndex::default()..PrepaintStateIndex::default(),
2159 paint_range: PaintIndex::default()..PaintIndex::default(),
2160 });
2161 }
2162
2163 /// Creates a new painting layer for the specified bounds. A "layer" is a batch
2164 /// of geometry that are non-overlapping and have the same draw order. This is typically used
2165 /// for performance reasons.
2166 ///
2167 /// This method should only be called as part of the paint phase of element drawing.
2168 pub fn paint_layer<R>(&mut self, bounds: Bounds<Pixels>, f: impl FnOnce(&mut Self) -> R) -> R {
2169 debug_assert_eq!(
2170 self.window.draw_phase,
2171 DrawPhase::Paint,
2172 "this method can only be called during paint"
2173 );
2174
2175 let scale_factor = self.scale_factor();
2176 let content_mask = self.content_mask();
2177 let clipped_bounds = bounds.intersect(&content_mask.bounds);
2178 if !clipped_bounds.is_empty() {
2179 self.window
2180 .next_frame
2181 .scene
2182 .push_layer(clipped_bounds.scale(scale_factor));
2183 }
2184
2185 let result = f(self);
2186
2187 if !clipped_bounds.is_empty() {
2188 self.window.next_frame.scene.pop_layer();
2189 }
2190
2191 result
2192 }
2193
2194 /// Paint one or more drop shadows into the scene for the next frame at the current z-index.
2195 ///
2196 /// This method should only be called as part of the paint phase of element drawing.
2197 pub fn paint_shadows(
2198 &mut self,
2199 bounds: Bounds<Pixels>,
2200 corner_radii: Corners<Pixels>,
2201 shadows: &[BoxShadow],
2202 ) {
2203 debug_assert_eq!(
2204 self.window.draw_phase,
2205 DrawPhase::Paint,
2206 "this method can only be called during paint"
2207 );
2208
2209 let scale_factor = self.scale_factor();
2210 let content_mask = self.content_mask();
2211 for shadow in shadows {
2212 let mut shadow_bounds = bounds;
2213 shadow_bounds.origin += shadow.offset;
2214 shadow_bounds.dilate(shadow.spread_radius);
2215 self.window.next_frame.scene.insert_primitive(Shadow {
2216 order: 0,
2217 blur_radius: shadow.blur_radius.scale(scale_factor),
2218 bounds: shadow_bounds.scale(scale_factor),
2219 content_mask: content_mask.scale(scale_factor),
2220 corner_radii: corner_radii.scale(scale_factor),
2221 color: shadow.color,
2222 });
2223 }
2224 }
2225
2226 /// Paint one or more quads into the scene for the next frame at the current stacking context.
2227 /// Quads are colored rectangular regions with an optional background, border, and corner radius.
2228 /// see [`fill`](crate::fill), [`outline`](crate::outline), and [`quad`](crate::quad) to construct this type.
2229 ///
2230 /// This method should only be called as part of the paint phase of element drawing.
2231 pub fn paint_quad(&mut self, quad: PaintQuad) {
2232 debug_assert_eq!(
2233 self.window.draw_phase,
2234 DrawPhase::Paint,
2235 "this method can only be called during paint"
2236 );
2237
2238 let scale_factor = self.scale_factor();
2239 let content_mask = self.content_mask();
2240 self.window.next_frame.scene.insert_primitive(Quad {
2241 order: 0,
2242 pad: 0,
2243 bounds: quad.bounds.scale(scale_factor),
2244 content_mask: content_mask.scale(scale_factor),
2245 background: quad.background,
2246 border_color: quad.border_color,
2247 corner_radii: quad.corner_radii.scale(scale_factor),
2248 border_widths: quad.border_widths.scale(scale_factor),
2249 });
2250 }
2251
2252 /// Paint the given `Path` into the scene for the next frame at the current z-index.
2253 ///
2254 /// This method should only be called as part of the paint phase of element drawing.
2255 pub fn paint_path(&mut self, mut path: Path<Pixels>, color: impl Into<Hsla>) {
2256 debug_assert_eq!(
2257 self.window.draw_phase,
2258 DrawPhase::Paint,
2259 "this method can only be called during paint"
2260 );
2261
2262 let scale_factor = self.scale_factor();
2263 let content_mask = self.content_mask();
2264 path.content_mask = content_mask;
2265 path.color = color.into();
2266 self.window
2267 .next_frame
2268 .scene
2269 .insert_primitive(path.scale(scale_factor));
2270 }
2271
2272 /// Paint an underline into the scene for the next frame at the current z-index.
2273 ///
2274 /// This method should only be called as part of the paint phase of element drawing.
2275 pub fn paint_underline(
2276 &mut self,
2277 origin: Point<Pixels>,
2278 width: Pixels,
2279 style: &UnderlineStyle,
2280 ) {
2281 debug_assert_eq!(
2282 self.window.draw_phase,
2283 DrawPhase::Paint,
2284 "this method can only be called during paint"
2285 );
2286
2287 let scale_factor = self.scale_factor();
2288 let height = if style.wavy {
2289 style.thickness * 3.
2290 } else {
2291 style.thickness
2292 };
2293 let bounds = Bounds {
2294 origin,
2295 size: size(width, height),
2296 };
2297 let content_mask = self.content_mask();
2298
2299 self.window.next_frame.scene.insert_primitive(Underline {
2300 order: 0,
2301 pad: 0,
2302 bounds: bounds.scale(scale_factor),
2303 content_mask: content_mask.scale(scale_factor),
2304 color: style.color.unwrap_or_default(),
2305 thickness: style.thickness.scale(scale_factor),
2306 wavy: style.wavy,
2307 });
2308 }
2309
2310 /// Paint a strikethrough into the scene for the next frame at the current z-index.
2311 ///
2312 /// This method should only be called as part of the paint phase of element drawing.
2313 pub fn paint_strikethrough(
2314 &mut self,
2315 origin: Point<Pixels>,
2316 width: Pixels,
2317 style: &StrikethroughStyle,
2318 ) {
2319 debug_assert_eq!(
2320 self.window.draw_phase,
2321 DrawPhase::Paint,
2322 "this method can only be called during paint"
2323 );
2324
2325 let scale_factor = self.scale_factor();
2326 let height = style.thickness;
2327 let bounds = Bounds {
2328 origin,
2329 size: size(width, height),
2330 };
2331 let content_mask = self.content_mask();
2332
2333 self.window.next_frame.scene.insert_primitive(Underline {
2334 order: 0,
2335 pad: 0,
2336 bounds: bounds.scale(scale_factor),
2337 content_mask: content_mask.scale(scale_factor),
2338 thickness: style.thickness.scale(scale_factor),
2339 color: style.color.unwrap_or_default(),
2340 wavy: false,
2341 });
2342 }
2343
2344 /// Paints a monochrome (non-emoji) glyph into the scene for the next frame at the current z-index.
2345 ///
2346 /// The y component of the origin is the baseline of the glyph.
2347 /// You should generally prefer to use the [`ShapedLine::paint`](crate::ShapedLine::paint) or
2348 /// [`WrappedLine::paint`](crate::WrappedLine::paint) methods in the [`TextSystem`](crate::TextSystem).
2349 /// This method is only useful if you need to paint a single glyph that has already been shaped.
2350 ///
2351 /// This method should only be called as part of the paint phase of element drawing.
2352 pub fn paint_glyph(
2353 &mut self,
2354 origin: Point<Pixels>,
2355 font_id: FontId,
2356 glyph_id: GlyphId,
2357 font_size: Pixels,
2358 color: Hsla,
2359 ) -> Result<()> {
2360 debug_assert_eq!(
2361 self.window.draw_phase,
2362 DrawPhase::Paint,
2363 "this method can only be called during paint"
2364 );
2365
2366 let scale_factor = self.scale_factor();
2367 let glyph_origin = origin.scale(scale_factor);
2368 let subpixel_variant = Point {
2369 x: (glyph_origin.x.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
2370 y: (glyph_origin.y.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
2371 };
2372 let params = RenderGlyphParams {
2373 font_id,
2374 glyph_id,
2375 font_size,
2376 subpixel_variant,
2377 scale_factor,
2378 is_emoji: false,
2379 };
2380
2381 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
2382 if !raster_bounds.is_zero() {
2383 let tile = self
2384 .window
2385 .sprite_atlas
2386 .get_or_insert_with(¶ms.clone().into(), &mut || {
2387 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
2388 Ok(Some((size, Cow::Owned(bytes))))
2389 })?
2390 .expect("Callback above only errors or returns Some");
2391 let bounds = Bounds {
2392 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
2393 size: tile.bounds.size.map(Into::into),
2394 };
2395 let content_mask = self.content_mask().scale(scale_factor);
2396 self.window
2397 .next_frame
2398 .scene
2399 .insert_primitive(MonochromeSprite {
2400 order: 0,
2401 pad: 0,
2402 bounds,
2403 content_mask,
2404 color,
2405 tile,
2406 transformation: TransformationMatrix::unit(),
2407 });
2408 }
2409 Ok(())
2410 }
2411
2412 /// Paints an emoji glyph into the scene for the next frame at the current z-index.
2413 ///
2414 /// The y component of the origin is the baseline of the glyph.
2415 /// You should generally prefer to use the [`ShapedLine::paint`](crate::ShapedLine::paint) or
2416 /// [`WrappedLine::paint`](crate::WrappedLine::paint) methods in the [`TextSystem`](crate::TextSystem).
2417 /// This method is only useful if you need to paint a single emoji that has already been shaped.
2418 ///
2419 /// This method should only be called as part of the paint phase of element drawing.
2420 pub fn paint_emoji(
2421 &mut self,
2422 origin: Point<Pixels>,
2423 font_id: FontId,
2424 glyph_id: GlyphId,
2425 font_size: Pixels,
2426 ) -> Result<()> {
2427 debug_assert_eq!(
2428 self.window.draw_phase,
2429 DrawPhase::Paint,
2430 "this method can only be called during paint"
2431 );
2432
2433 let scale_factor = self.scale_factor();
2434 let glyph_origin = origin.scale(scale_factor);
2435 let params = RenderGlyphParams {
2436 font_id,
2437 glyph_id,
2438 font_size,
2439 // We don't render emojis with subpixel variants.
2440 subpixel_variant: Default::default(),
2441 scale_factor,
2442 is_emoji: true,
2443 };
2444
2445 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
2446 if !raster_bounds.is_zero() {
2447 let tile = self
2448 .window
2449 .sprite_atlas
2450 .get_or_insert_with(¶ms.clone().into(), &mut || {
2451 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
2452 Ok(Some((size, Cow::Owned(bytes))))
2453 })?
2454 .expect("Callback above only errors or returns Some");
2455
2456 let bounds = Bounds {
2457 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
2458 size: tile.bounds.size.map(Into::into),
2459 };
2460 let content_mask = self.content_mask().scale(scale_factor);
2461
2462 self.window
2463 .next_frame
2464 .scene
2465 .insert_primitive(PolychromeSprite {
2466 order: 0,
2467 grayscale: false,
2468 bounds,
2469 corner_radii: Default::default(),
2470 content_mask,
2471 tile,
2472 });
2473 }
2474 Ok(())
2475 }
2476
2477 /// Paint a monochrome SVG into the scene for the next frame at the current stacking context.
2478 ///
2479 /// This method should only be called as part of the paint phase of element drawing.
2480 pub fn paint_svg(
2481 &mut self,
2482 bounds: Bounds<Pixels>,
2483 path: SharedString,
2484 transformation: TransformationMatrix,
2485 color: Hsla,
2486 ) -> Result<()> {
2487 debug_assert_eq!(
2488 self.window.draw_phase,
2489 DrawPhase::Paint,
2490 "this method can only be called during paint"
2491 );
2492
2493 let scale_factor = self.scale_factor();
2494 let bounds = bounds.scale(scale_factor);
2495 // Render the SVG at twice the size to get a higher quality result.
2496 let params = RenderSvgParams {
2497 path,
2498 size: bounds
2499 .size
2500 .map(|pixels| DevicePixels::from((pixels.0 * 2.).ceil() as i32)),
2501 };
2502
2503 let Some(tile) =
2504 self.window
2505 .sprite_atlas
2506 .get_or_insert_with(¶ms.clone().into(), &mut || {
2507 let Some(bytes) = self.svg_renderer.render(¶ms)? else {
2508 return Ok(None);
2509 };
2510 Ok(Some((params.size, Cow::Owned(bytes))))
2511 })?
2512 else {
2513 return Ok(());
2514 };
2515 let content_mask = self.content_mask().scale(scale_factor);
2516
2517 self.window
2518 .next_frame
2519 .scene
2520 .insert_primitive(MonochromeSprite {
2521 order: 0,
2522 pad: 0,
2523 bounds,
2524 content_mask,
2525 color,
2526 tile,
2527 transformation,
2528 });
2529
2530 Ok(())
2531 }
2532
2533 /// Paint an image into the scene for the next frame at the current z-index.
2534 ///
2535 /// This method should only be called as part of the paint phase of element drawing.
2536 pub fn paint_image(
2537 &mut self,
2538 bounds: Bounds<Pixels>,
2539 corner_radii: Corners<Pixels>,
2540 data: Arc<ImageData>,
2541 grayscale: bool,
2542 ) -> Result<()> {
2543 debug_assert_eq!(
2544 self.window.draw_phase,
2545 DrawPhase::Paint,
2546 "this method can only be called during paint"
2547 );
2548
2549 let scale_factor = self.scale_factor();
2550 let bounds = bounds.scale(scale_factor);
2551 let params = RenderImageParams { image_id: data.id };
2552
2553 let tile = self
2554 .window
2555 .sprite_atlas
2556 .get_or_insert_with(¶ms.clone().into(), &mut || {
2557 Ok(Some((data.size(), Cow::Borrowed(data.as_bytes()))))
2558 })?
2559 .expect("Callback above only returns Some");
2560 let content_mask = self.content_mask().scale(scale_factor);
2561 let corner_radii = corner_radii.scale(scale_factor);
2562
2563 self.window
2564 .next_frame
2565 .scene
2566 .insert_primitive(PolychromeSprite {
2567 order: 0,
2568 grayscale,
2569 bounds,
2570 content_mask,
2571 corner_radii,
2572 tile,
2573 });
2574 Ok(())
2575 }
2576
2577 /// Paint a surface into the scene for the next frame at the current z-index.
2578 ///
2579 /// This method should only be called as part of the paint phase of element drawing.
2580 #[cfg(target_os = "macos")]
2581 pub fn paint_surface(&mut self, bounds: Bounds<Pixels>, image_buffer: CVImageBuffer) {
2582 debug_assert_eq!(
2583 self.window.draw_phase,
2584 DrawPhase::Paint,
2585 "this method can only be called during paint"
2586 );
2587
2588 let scale_factor = self.scale_factor();
2589 let bounds = bounds.scale(scale_factor);
2590 let content_mask = self.content_mask().scale(scale_factor);
2591 self.window
2592 .next_frame
2593 .scene
2594 .insert_primitive(crate::Surface {
2595 order: 0,
2596 bounds,
2597 content_mask,
2598 image_buffer,
2599 });
2600 }
2601
2602 #[must_use]
2603 /// Add a node to the layout tree for the current frame. Takes the `Style` of the element for which
2604 /// layout is being requested, along with the layout ids of any children. This method is called during
2605 /// calls to the [`Element::request_layout`] trait method and enables any element to participate in layout.
2606 ///
2607 /// This method should only be called as part of the request_layout or prepaint phase of element drawing.
2608 pub fn request_layout(
2609 &mut self,
2610 style: Style,
2611 children: impl IntoIterator<Item = LayoutId>,
2612 ) -> LayoutId {
2613 debug_assert_eq!(
2614 self.window.draw_phase,
2615 DrawPhase::Prepaint,
2616 "this method can only be called during request_layout, or prepaint"
2617 );
2618
2619 self.app.layout_id_buffer.clear();
2620 self.app.layout_id_buffer.extend(children);
2621 let rem_size = self.rem_size();
2622
2623 self.window.layout_engine.as_mut().unwrap().request_layout(
2624 style,
2625 rem_size,
2626 &self.app.layout_id_buffer,
2627 )
2628 }
2629
2630 /// Add a node to the layout tree for the current frame. Instead of taking a `Style` and children,
2631 /// this variant takes a function that is invoked during layout so you can use arbitrary logic to
2632 /// determine the element's size. One place this is used internally is when measuring text.
2633 ///
2634 /// The given closure is invoked at layout time with the known dimensions and available space and
2635 /// returns a `Size`.
2636 ///
2637 /// This method should only be called as part of the request_layout or prepaint phase of element drawing.
2638 pub fn request_measured_layout<
2639 F: FnMut(Size<Option<Pixels>>, Size<AvailableSpace>, &mut WindowContext) -> Size<Pixels>
2640 + 'static,
2641 >(
2642 &mut self,
2643 style: Style,
2644 measure: F,
2645 ) -> LayoutId {
2646 debug_assert_eq!(
2647 self.window.draw_phase,
2648 DrawPhase::Prepaint,
2649 "this method can only be called during request_layout, or prepaint"
2650 );
2651
2652 let rem_size = self.rem_size();
2653 self.window
2654 .layout_engine
2655 .as_mut()
2656 .unwrap()
2657 .request_measured_layout(style, rem_size, measure)
2658 }
2659
2660 /// Compute the layout for the given id within the given available space.
2661 /// This method is called for its side effect, typically by the framework prior to painting.
2662 /// After calling it, you can request the bounds of the given layout node id or any descendant.
2663 ///
2664 /// This method should only be called as part of the prepaint phase of element drawing.
2665 pub fn compute_layout(&mut self, layout_id: LayoutId, available_space: Size<AvailableSpace>) {
2666 debug_assert_eq!(
2667 self.window.draw_phase,
2668 DrawPhase::Prepaint,
2669 "this method can only be called during request_layout, or prepaint"
2670 );
2671
2672 let mut layout_engine = self.window.layout_engine.take().unwrap();
2673 layout_engine.compute_layout(layout_id, available_space, self);
2674 self.window.layout_engine = Some(layout_engine);
2675 }
2676
2677 /// Obtain the bounds computed for the given LayoutId relative to the window. This method will usually be invoked by
2678 /// GPUI itself automatically in order to pass your element its `Bounds` automatically.
2679 ///
2680 /// This method should only be called as part of element drawing.
2681 pub fn layout_bounds(&mut self, layout_id: LayoutId) -> Bounds<Pixels> {
2682 debug_assert_eq!(
2683 self.window.draw_phase,
2684 DrawPhase::Prepaint,
2685 "this method can only be called during request_layout, prepaint, or paint"
2686 );
2687
2688 let mut bounds = self
2689 .window
2690 .layout_engine
2691 .as_mut()
2692 .unwrap()
2693 .layout_bounds(layout_id)
2694 .map(Into::into);
2695 bounds.origin += self.element_offset();
2696 bounds
2697 }
2698
2699 /// This method should be called during `prepaint`. You can use
2700 /// the returned [Hitbox] during `paint` or in an event handler
2701 /// to determine whether the inserted hitbox was the topmost.
2702 ///
2703 /// This method should only be called as part of the prepaint phase of element drawing.
2704 pub fn insert_hitbox(&mut self, bounds: Bounds<Pixels>, opaque: bool) -> Hitbox {
2705 debug_assert_eq!(
2706 self.window.draw_phase,
2707 DrawPhase::Prepaint,
2708 "this method can only be called during prepaint"
2709 );
2710
2711 let content_mask = self.content_mask();
2712 let window = &mut self.window;
2713 let id = window.next_hitbox_id;
2714 window.next_hitbox_id.0 += 1;
2715 let hitbox = Hitbox {
2716 id,
2717 bounds,
2718 content_mask,
2719 opaque,
2720 };
2721 window.next_frame.hitboxes.push(hitbox.clone());
2722 hitbox
2723 }
2724
2725 /// Sets the key context for the current element. This context will be used to translate
2726 /// keybindings into actions.
2727 ///
2728 /// This method should only be called as part of the paint phase of element drawing.
2729 pub fn set_key_context(&mut self, context: KeyContext) {
2730 debug_assert_eq!(
2731 self.window.draw_phase,
2732 DrawPhase::Paint,
2733 "this method can only be called during paint"
2734 );
2735 self.window
2736 .next_frame
2737 .dispatch_tree
2738 .set_key_context(context);
2739 }
2740
2741 /// Sets the focus handle for the current element. This handle will be used to manage focus state
2742 /// and keyboard event dispatch for the element.
2743 ///
2744 /// This method should only be called as part of the paint phase of element drawing.
2745 pub fn set_focus_handle(&mut self, focus_handle: &FocusHandle) {
2746 debug_assert_eq!(
2747 self.window.draw_phase,
2748 DrawPhase::Paint,
2749 "this method can only be called during paint"
2750 );
2751 self.window
2752 .next_frame
2753 .dispatch_tree
2754 .set_focus_id(focus_handle.id);
2755 }
2756
2757 /// Sets the view id for the current element, which will be used to manage view caching.
2758 ///
2759 /// This method should only be called as part of element prepaint. We plan on removing this
2760 /// method eventually when we solve some issues that require us to construct editor elements
2761 /// directly instead of always using editors via views.
2762 pub fn set_view_id(&mut self, view_id: EntityId) {
2763 debug_assert_eq!(
2764 self.window.draw_phase,
2765 DrawPhase::Prepaint,
2766 "this method can only be called during prepaint"
2767 );
2768 self.window.next_frame.dispatch_tree.set_view_id(view_id);
2769 }
2770
2771 /// Get the last view id for the current element
2772 pub fn parent_view_id(&mut self) -> Option<EntityId> {
2773 self.window.next_frame.dispatch_tree.parent_view_id()
2774 }
2775
2776 /// Sets an input handler, such as [`ElementInputHandler`][element_input_handler], which interfaces with the
2777 /// platform to receive textual input with proper integration with concerns such
2778 /// as IME interactions. This handler will be active for the upcoming frame until the following frame is
2779 /// rendered.
2780 ///
2781 /// This method should only be called as part of the paint phase of element drawing.
2782 ///
2783 /// [element_input_handler]: crate::ElementInputHandler
2784 pub fn handle_input(&mut self, focus_handle: &FocusHandle, input_handler: impl InputHandler) {
2785 debug_assert_eq!(
2786 self.window.draw_phase,
2787 DrawPhase::Paint,
2788 "this method can only be called during paint"
2789 );
2790
2791 if focus_handle.is_focused(self) {
2792 let cx = self.to_async();
2793 self.window
2794 .next_frame
2795 .input_handlers
2796 .push(Some(PlatformInputHandler::new(cx, Box::new(input_handler))));
2797 }
2798 }
2799
2800 /// Register a mouse event listener on the window for the next frame. The type of event
2801 /// is determined by the first parameter of the given listener. When the next frame is rendered
2802 /// the listener will be cleared.
2803 ///
2804 /// This method should only be called as part of the paint phase of element drawing.
2805 pub fn on_mouse_event<Event: MouseEvent>(
2806 &mut self,
2807 mut handler: impl FnMut(&Event, DispatchPhase, &mut WindowContext) + 'static,
2808 ) {
2809 debug_assert_eq!(
2810 self.window.draw_phase,
2811 DrawPhase::Paint,
2812 "this method can only be called during paint"
2813 );
2814
2815 self.window.next_frame.mouse_listeners.push(Some(Box::new(
2816 move |event: &dyn Any, phase: DispatchPhase, cx: &mut WindowContext<'_>| {
2817 if let Some(event) = event.downcast_ref() {
2818 handler(event, phase, cx)
2819 }
2820 },
2821 )));
2822 }
2823
2824 /// Register a key event listener on the window for the next frame. The type of event
2825 /// is determined by the first parameter of the given listener. When the next frame is rendered
2826 /// the listener will be cleared.
2827 ///
2828 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
2829 /// a specific need to register a global listener.
2830 ///
2831 /// This method should only be called as part of the paint phase of element drawing.
2832 pub fn on_key_event<Event: KeyEvent>(
2833 &mut self,
2834 listener: impl Fn(&Event, DispatchPhase, &mut WindowContext) + 'static,
2835 ) {
2836 debug_assert_eq!(
2837 self.window.draw_phase,
2838 DrawPhase::Paint,
2839 "this method can only be called during paint"
2840 );
2841
2842 self.window.next_frame.dispatch_tree.on_key_event(Rc::new(
2843 move |event: &dyn Any, phase, cx: &mut WindowContext<'_>| {
2844 if let Some(event) = event.downcast_ref::<Event>() {
2845 listener(event, phase, cx)
2846 }
2847 },
2848 ));
2849 }
2850
2851 /// Register a modifiers changed event listener on the window for the next frame.
2852 ///
2853 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
2854 /// a specific need to register a global listener.
2855 ///
2856 /// This method should only be called as part of the paint phase of element drawing.
2857 pub fn on_modifiers_changed(
2858 &mut self,
2859 listener: impl Fn(&ModifiersChangedEvent, &mut WindowContext) + 'static,
2860 ) {
2861 debug_assert_eq!(
2862 self.window.draw_phase,
2863 DrawPhase::Paint,
2864 "this method can only be called during paint"
2865 );
2866
2867 self.window
2868 .next_frame
2869 .dispatch_tree
2870 .on_modifiers_changed(Rc::new(
2871 move |event: &ModifiersChangedEvent, cx: &mut WindowContext<'_>| {
2872 listener(event, cx)
2873 },
2874 ));
2875 }
2876
2877 fn reset_cursor_style(&self) {
2878 // Set the cursor only if we're the active window.
2879 if self.is_window_active() {
2880 let style = self
2881 .window
2882 .rendered_frame
2883 .cursor_styles
2884 .iter()
2885 .rev()
2886 .find(|request| request.hitbox_id.is_hovered(self))
2887 .map(|request| request.style)
2888 .unwrap_or(CursorStyle::Arrow);
2889 self.platform.set_cursor_style(style);
2890 }
2891 }
2892
2893 /// Dispatch a given keystroke as though the user had typed it.
2894 /// You can create a keystroke with Keystroke::parse("").
2895 pub fn dispatch_keystroke(&mut self, keystroke: Keystroke) -> bool {
2896 let keystroke = keystroke.with_simulated_ime();
2897 let result = self.dispatch_event(PlatformInput::KeyDown(KeyDownEvent {
2898 keystroke: keystroke.clone(),
2899 is_held: false,
2900 }));
2901 if !result.propagate {
2902 return true;
2903 }
2904
2905 if let Some(input) = keystroke.ime_key {
2906 if let Some(mut input_handler) = self.window.platform_window.take_input_handler() {
2907 input_handler.dispatch_input(&input, self);
2908 self.window.platform_window.set_input_handler(input_handler);
2909 return true;
2910 }
2911 }
2912
2913 false
2914 }
2915
2916 /// Represent this action as a key binding string, to display in the UI.
2917 pub fn keystroke_text_for(&self, action: &dyn Action) -> String {
2918 self.bindings_for_action(action)
2919 .into_iter()
2920 .next()
2921 .map(|binding| {
2922 binding
2923 .keystrokes()
2924 .iter()
2925 .map(ToString::to_string)
2926 .collect::<Vec<_>>()
2927 .join(" ")
2928 })
2929 .unwrap_or_else(|| action.name().to_string())
2930 }
2931
2932 /// Dispatch a mouse or keyboard event on the window.
2933 #[profiling::function]
2934 pub fn dispatch_event(&mut self, event: PlatformInput) -> DispatchEventResult {
2935 self.window.last_input_timestamp.set(Instant::now());
2936 // Handlers may set this to false by calling `stop_propagation`.
2937 self.app.propagate_event = true;
2938 // Handlers may set this to true by calling `prevent_default`.
2939 self.window.default_prevented = false;
2940
2941 let event = match event {
2942 // Track the mouse position with our own state, since accessing the platform
2943 // API for the mouse position can only occur on the main thread.
2944 PlatformInput::MouseMove(mouse_move) => {
2945 self.window.mouse_position = mouse_move.position;
2946 self.window.modifiers = mouse_move.modifiers;
2947 PlatformInput::MouseMove(mouse_move)
2948 }
2949 PlatformInput::MouseDown(mouse_down) => {
2950 self.window.mouse_position = mouse_down.position;
2951 self.window.modifiers = mouse_down.modifiers;
2952 PlatformInput::MouseDown(mouse_down)
2953 }
2954 PlatformInput::MouseUp(mouse_up) => {
2955 self.window.mouse_position = mouse_up.position;
2956 self.window.modifiers = mouse_up.modifiers;
2957 PlatformInput::MouseUp(mouse_up)
2958 }
2959 PlatformInput::MouseExited(mouse_exited) => {
2960 self.window.modifiers = mouse_exited.modifiers;
2961 PlatformInput::MouseExited(mouse_exited)
2962 }
2963 PlatformInput::ModifiersChanged(modifiers_changed) => {
2964 self.window.modifiers = modifiers_changed.modifiers;
2965 PlatformInput::ModifiersChanged(modifiers_changed)
2966 }
2967 PlatformInput::ScrollWheel(scroll_wheel) => {
2968 self.window.mouse_position = scroll_wheel.position;
2969 self.window.modifiers = scroll_wheel.modifiers;
2970 PlatformInput::ScrollWheel(scroll_wheel)
2971 }
2972 // Translate dragging and dropping of external files from the operating system
2973 // to internal drag and drop events.
2974 PlatformInput::FileDrop(file_drop) => match file_drop {
2975 FileDropEvent::Entered { position, paths } => {
2976 self.window.mouse_position = position;
2977 if self.active_drag.is_none() {
2978 self.active_drag = Some(AnyDrag {
2979 value: Box::new(paths.clone()),
2980 view: self.new_view(|_| paths).into(),
2981 cursor_offset: position,
2982 });
2983 }
2984 PlatformInput::MouseMove(MouseMoveEvent {
2985 position,
2986 pressed_button: Some(MouseButton::Left),
2987 modifiers: Modifiers::default(),
2988 })
2989 }
2990 FileDropEvent::Pending { position } => {
2991 self.window.mouse_position = position;
2992 PlatformInput::MouseMove(MouseMoveEvent {
2993 position,
2994 pressed_button: Some(MouseButton::Left),
2995 modifiers: Modifiers::default(),
2996 })
2997 }
2998 FileDropEvent::Submit { position } => {
2999 self.activate(true);
3000 self.window.mouse_position = position;
3001 PlatformInput::MouseUp(MouseUpEvent {
3002 button: MouseButton::Left,
3003 position,
3004 modifiers: Modifiers::default(),
3005 click_count: 1,
3006 })
3007 }
3008 FileDropEvent::Exited => {
3009 self.active_drag.take();
3010 PlatformInput::FileDrop(FileDropEvent::Exited)
3011 }
3012 },
3013 PlatformInput::KeyDown(_) | PlatformInput::KeyUp(_) => event,
3014 };
3015
3016 if let Some(any_mouse_event) = event.mouse_event() {
3017 self.dispatch_mouse_event(any_mouse_event);
3018 } else if let Some(any_key_event) = event.keyboard_event() {
3019 self.dispatch_key_event(any_key_event);
3020 }
3021
3022 DispatchEventResult {
3023 propagate: self.app.propagate_event,
3024 default_prevented: self.window.default_prevented,
3025 }
3026 }
3027
3028 fn dispatch_mouse_event(&mut self, event: &dyn Any) {
3029 let hit_test = self.window.rendered_frame.hit_test(self.mouse_position());
3030 if hit_test != self.window.mouse_hit_test {
3031 self.window.mouse_hit_test = hit_test;
3032 self.reset_cursor_style();
3033 }
3034
3035 let mut mouse_listeners = mem::take(&mut self.window.rendered_frame.mouse_listeners);
3036
3037 // Capture phase, events bubble from back to front. Handlers for this phase are used for
3038 // special purposes, such as detecting events outside of a given Bounds.
3039 for listener in &mut mouse_listeners {
3040 let listener = listener.as_mut().unwrap();
3041 listener(event, DispatchPhase::Capture, self);
3042 if !self.app.propagate_event {
3043 break;
3044 }
3045 }
3046
3047 // Bubble phase, where most normal handlers do their work.
3048 if self.app.propagate_event {
3049 for listener in mouse_listeners.iter_mut().rev() {
3050 let listener = listener.as_mut().unwrap();
3051 listener(event, DispatchPhase::Bubble, self);
3052 if !self.app.propagate_event {
3053 break;
3054 }
3055 }
3056 }
3057
3058 self.window.rendered_frame.mouse_listeners = mouse_listeners;
3059
3060 if self.has_active_drag() {
3061 if event.is::<MouseMoveEvent>() {
3062 // If this was a mouse move event, redraw the window so that the
3063 // active drag can follow the mouse cursor.
3064 self.refresh();
3065 } else if event.is::<MouseUpEvent>() {
3066 // If this was a mouse up event, cancel the active drag and redraw
3067 // the window.
3068 self.active_drag = None;
3069 self.refresh();
3070 }
3071 }
3072 }
3073
3074 fn dispatch_key_event(&mut self, event: &dyn Any) {
3075 if self.window.dirty.get() {
3076 self.draw();
3077 }
3078
3079 let node_id = self
3080 .window
3081 .focus
3082 .and_then(|focus_id| {
3083 self.window
3084 .rendered_frame
3085 .dispatch_tree
3086 .focusable_node_id(focus_id)
3087 })
3088 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3089
3090 let dispatch_path = self
3091 .window
3092 .rendered_frame
3093 .dispatch_tree
3094 .dispatch_path(node_id);
3095
3096 if let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() {
3097 let KeymatchResult { bindings, pending } = self
3098 .window
3099 .rendered_frame
3100 .dispatch_tree
3101 .dispatch_key(&key_down_event.keystroke, &dispatch_path);
3102
3103 if pending {
3104 let mut currently_pending = self.window.pending_input.take().unwrap_or_default();
3105 if currently_pending.focus.is_some() && currently_pending.focus != self.window.focus
3106 {
3107 currently_pending = PendingInput::default();
3108 }
3109 currently_pending.focus = self.window.focus;
3110 currently_pending
3111 .keystrokes
3112 .push(key_down_event.keystroke.clone());
3113 for binding in bindings {
3114 currently_pending.bindings.push(binding);
3115 }
3116
3117 currently_pending.timer = Some(self.spawn(|mut cx| async move {
3118 cx.background_executor.timer(Duration::from_secs(1)).await;
3119 cx.update(move |cx| {
3120 cx.clear_pending_keystrokes();
3121 let Some(currently_pending) = cx.window.pending_input.take() else {
3122 return;
3123 };
3124 cx.replay_pending_input(currently_pending)
3125 })
3126 .log_err();
3127 }));
3128
3129 self.window.pending_input = Some(currently_pending);
3130
3131 self.propagate_event = false;
3132 return;
3133 } else if let Some(currently_pending) = self.window.pending_input.take() {
3134 if bindings
3135 .iter()
3136 .all(|binding| !currently_pending.used_by_binding(binding))
3137 {
3138 self.replay_pending_input(currently_pending)
3139 }
3140 }
3141
3142 if !bindings.is_empty() {
3143 self.clear_pending_keystrokes();
3144 }
3145
3146 self.propagate_event = true;
3147 for binding in bindings {
3148 self.dispatch_action_on_node(node_id, binding.action.as_ref());
3149 if !self.propagate_event {
3150 self.dispatch_keystroke_observers(event, Some(binding.action));
3151 return;
3152 }
3153 }
3154 }
3155
3156 self.dispatch_key_down_up_event(event, &dispatch_path);
3157 if !self.propagate_event {
3158 return;
3159 }
3160
3161 self.dispatch_modifiers_changed_event(event, &dispatch_path);
3162 if !self.propagate_event {
3163 return;
3164 }
3165
3166 self.dispatch_keystroke_observers(event, None);
3167 }
3168
3169 fn dispatch_key_down_up_event(
3170 &mut self,
3171 event: &dyn Any,
3172 dispatch_path: &SmallVec<[DispatchNodeId; 32]>,
3173 ) {
3174 // Capture phase
3175 for node_id in dispatch_path {
3176 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3177
3178 for key_listener in node.key_listeners.clone() {
3179 key_listener(event, DispatchPhase::Capture, self);
3180 if !self.propagate_event {
3181 return;
3182 }
3183 }
3184 }
3185
3186 // Bubble phase
3187 for node_id in dispatch_path.iter().rev() {
3188 // Handle low level key events
3189 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3190 for key_listener in node.key_listeners.clone() {
3191 key_listener(event, DispatchPhase::Bubble, self);
3192 if !self.propagate_event {
3193 return;
3194 }
3195 }
3196 }
3197 }
3198
3199 fn dispatch_modifiers_changed_event(
3200 &mut self,
3201 event: &dyn Any,
3202 dispatch_path: &SmallVec<[DispatchNodeId; 32]>,
3203 ) {
3204 let Some(event) = event.downcast_ref::<ModifiersChangedEvent>() else {
3205 return;
3206 };
3207 for node_id in dispatch_path.iter().rev() {
3208 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3209 for listener in node.modifiers_changed_listeners.clone() {
3210 listener(event, self);
3211 if !self.propagate_event {
3212 return;
3213 }
3214 }
3215 }
3216 }
3217
3218 /// Determine whether a potential multi-stroke key binding is in progress on this window.
3219 pub fn has_pending_keystrokes(&self) -> bool {
3220 self.window
3221 .rendered_frame
3222 .dispatch_tree
3223 .has_pending_keystrokes()
3224 }
3225
3226 fn replay_pending_input(&mut self, currently_pending: PendingInput) {
3227 let node_id = self
3228 .window
3229 .focus
3230 .and_then(|focus_id| {
3231 self.window
3232 .rendered_frame
3233 .dispatch_tree
3234 .focusable_node_id(focus_id)
3235 })
3236 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3237
3238 if self.window.focus != currently_pending.focus {
3239 return;
3240 }
3241
3242 let input = currently_pending.input();
3243
3244 self.propagate_event = true;
3245 for binding in currently_pending.bindings {
3246 self.dispatch_action_on_node(node_id, binding.action.as_ref());
3247 if !self.propagate_event {
3248 return;
3249 }
3250 }
3251
3252 let dispatch_path = self
3253 .window
3254 .rendered_frame
3255 .dispatch_tree
3256 .dispatch_path(node_id);
3257
3258 for keystroke in currently_pending.keystrokes {
3259 let event = KeyDownEvent {
3260 keystroke,
3261 is_held: false,
3262 };
3263
3264 self.dispatch_key_down_up_event(&event, &dispatch_path);
3265 if !self.propagate_event {
3266 return;
3267 }
3268 }
3269
3270 if !input.is_empty() {
3271 if let Some(mut input_handler) = self.window.platform_window.take_input_handler() {
3272 input_handler.dispatch_input(&input, self);
3273 self.window.platform_window.set_input_handler(input_handler)
3274 }
3275 }
3276 }
3277
3278 fn dispatch_action_on_node(&mut self, node_id: DispatchNodeId, action: &dyn Action) {
3279 let dispatch_path = self
3280 .window
3281 .rendered_frame
3282 .dispatch_tree
3283 .dispatch_path(node_id);
3284
3285 // Capture phase for global actions.
3286 self.propagate_event = true;
3287 if let Some(mut global_listeners) = self
3288 .global_action_listeners
3289 .remove(&action.as_any().type_id())
3290 {
3291 for listener in &global_listeners {
3292 listener(action.as_any(), DispatchPhase::Capture, self);
3293 if !self.propagate_event {
3294 break;
3295 }
3296 }
3297
3298 global_listeners.extend(
3299 self.global_action_listeners
3300 .remove(&action.as_any().type_id())
3301 .unwrap_or_default(),
3302 );
3303
3304 self.global_action_listeners
3305 .insert(action.as_any().type_id(), global_listeners);
3306 }
3307
3308 if !self.propagate_event {
3309 return;
3310 }
3311
3312 // Capture phase for window actions.
3313 for node_id in &dispatch_path {
3314 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3315 for DispatchActionListener {
3316 action_type,
3317 listener,
3318 } in node.action_listeners.clone()
3319 {
3320 let any_action = action.as_any();
3321 if action_type == any_action.type_id() {
3322 listener(any_action, DispatchPhase::Capture, self);
3323
3324 if !self.propagate_event {
3325 return;
3326 }
3327 }
3328 }
3329 }
3330
3331 // Bubble phase for window actions.
3332 for node_id in dispatch_path.iter().rev() {
3333 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3334 for DispatchActionListener {
3335 action_type,
3336 listener,
3337 } in node.action_listeners.clone()
3338 {
3339 let any_action = action.as_any();
3340 if action_type == any_action.type_id() {
3341 self.propagate_event = false; // Actions stop propagation by default during the bubble phase
3342 listener(any_action, DispatchPhase::Bubble, self);
3343
3344 if !self.propagate_event {
3345 return;
3346 }
3347 }
3348 }
3349 }
3350
3351 // Bubble phase for global actions.
3352 if let Some(mut global_listeners) = self
3353 .global_action_listeners
3354 .remove(&action.as_any().type_id())
3355 {
3356 for listener in global_listeners.iter().rev() {
3357 self.propagate_event = false; // Actions stop propagation by default during the bubble phase
3358
3359 listener(action.as_any(), DispatchPhase::Bubble, self);
3360 if !self.propagate_event {
3361 break;
3362 }
3363 }
3364
3365 global_listeners.extend(
3366 self.global_action_listeners
3367 .remove(&action.as_any().type_id())
3368 .unwrap_or_default(),
3369 );
3370
3371 self.global_action_listeners
3372 .insert(action.as_any().type_id(), global_listeners);
3373 }
3374 }
3375
3376 /// Register the given handler to be invoked whenever the global of the given type
3377 /// is updated.
3378 pub fn observe_global<G: Global>(
3379 &mut self,
3380 f: impl Fn(&mut WindowContext<'_>) + 'static,
3381 ) -> Subscription {
3382 let window_handle = self.window.handle;
3383 let (subscription, activate) = self.global_observers.insert(
3384 TypeId::of::<G>(),
3385 Box::new(move |cx| window_handle.update(cx, |_, cx| f(cx)).is_ok()),
3386 );
3387 self.app.defer(move |_| activate());
3388 subscription
3389 }
3390
3391 /// Focus the current window and bring it to the foreground at the platform level.
3392 pub fn activate_window(&self) {
3393 self.window.platform_window.activate();
3394 }
3395
3396 /// Minimize the current window at the platform level.
3397 pub fn minimize_window(&self) {
3398 self.window.platform_window.minimize();
3399 }
3400
3401 /// Toggle full screen status on the current window at the platform level.
3402 pub fn toggle_fullscreen(&self) {
3403 self.window.platform_window.toggle_fullscreen();
3404 }
3405
3406 /// Present a platform dialog.
3407 /// The provided message will be presented, along with buttons for each answer.
3408 /// When a button is clicked, the returned Receiver will receive the index of the clicked button.
3409 pub fn prompt(
3410 &mut self,
3411 level: PromptLevel,
3412 message: &str,
3413 detail: Option<&str>,
3414 answers: &[&str],
3415 ) -> oneshot::Receiver<usize> {
3416 let prompt_builder = self.app.prompt_builder.take();
3417 let Some(prompt_builder) = prompt_builder else {
3418 unreachable!("Re-entrant window prompting is not supported by GPUI");
3419 };
3420
3421 let receiver = match &prompt_builder {
3422 PromptBuilder::Default => self
3423 .window
3424 .platform_window
3425 .prompt(level, message, detail, answers)
3426 .unwrap_or_else(|| {
3427 self.build_custom_prompt(&prompt_builder, level, message, detail, answers)
3428 }),
3429 PromptBuilder::Custom(_) => {
3430 self.build_custom_prompt(&prompt_builder, level, message, detail, answers)
3431 }
3432 };
3433
3434 self.app.prompt_builder = Some(prompt_builder);
3435
3436 receiver
3437 }
3438
3439 fn build_custom_prompt(
3440 &mut self,
3441 prompt_builder: &PromptBuilder,
3442 level: PromptLevel,
3443 message: &str,
3444 detail: Option<&str>,
3445 answers: &[&str],
3446 ) -> oneshot::Receiver<usize> {
3447 let (sender, receiver) = oneshot::channel();
3448 let handle = PromptHandle::new(sender);
3449 let handle = (prompt_builder)(level, message, detail, answers, handle, self);
3450 self.window.prompt = Some(handle);
3451 receiver
3452 }
3453
3454 /// Returns all available actions for the focused element.
3455 pub fn available_actions(&self) -> Vec<Box<dyn Action>> {
3456 let node_id = self
3457 .window
3458 .focus
3459 .and_then(|focus_id| {
3460 self.window
3461 .rendered_frame
3462 .dispatch_tree
3463 .focusable_node_id(focus_id)
3464 })
3465 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3466
3467 let mut actions = self
3468 .window
3469 .rendered_frame
3470 .dispatch_tree
3471 .available_actions(node_id);
3472 for action_type in self.global_action_listeners.keys() {
3473 if let Err(ix) = actions.binary_search_by_key(action_type, |a| a.as_any().type_id()) {
3474 let action = self.actions.build_action_type(action_type).ok();
3475 if let Some(action) = action {
3476 actions.insert(ix, action);
3477 }
3478 }
3479 }
3480 actions
3481 }
3482
3483 /// Returns key bindings that invoke the given action on the currently focused element.
3484 pub fn bindings_for_action(&self, action: &dyn Action) -> Vec<KeyBinding> {
3485 self.window
3486 .rendered_frame
3487 .dispatch_tree
3488 .bindings_for_action(
3489 action,
3490 &self.window.rendered_frame.dispatch_tree.context_stack,
3491 )
3492 }
3493
3494 /// Returns any bindings that would invoke the given action on the given focus handle if it were focused.
3495 pub fn bindings_for_action_in(
3496 &self,
3497 action: &dyn Action,
3498 focus_handle: &FocusHandle,
3499 ) -> Vec<KeyBinding> {
3500 let dispatch_tree = &self.window.rendered_frame.dispatch_tree;
3501
3502 let Some(node_id) = dispatch_tree.focusable_node_id(focus_handle.id) else {
3503 return vec![];
3504 };
3505 let context_stack: Vec<_> = dispatch_tree
3506 .dispatch_path(node_id)
3507 .into_iter()
3508 .filter_map(|node_id| dispatch_tree.node(node_id).context.clone())
3509 .collect();
3510 dispatch_tree.bindings_for_action(action, &context_stack)
3511 }
3512
3513 /// Returns a generic event listener that invokes the given listener with the view and context associated with the given view handle.
3514 pub fn listener_for<V: Render, E>(
3515 &self,
3516 view: &View<V>,
3517 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
3518 ) -> impl Fn(&E, &mut WindowContext) + 'static {
3519 let view = view.downgrade();
3520 move |e: &E, cx: &mut WindowContext| {
3521 view.update(cx, |view, cx| f(view, e, cx)).ok();
3522 }
3523 }
3524
3525 /// Returns a generic handler that invokes the given handler with the view and context associated with the given view handle.
3526 pub fn handler_for<V: Render>(
3527 &self,
3528 view: &View<V>,
3529 f: impl Fn(&mut V, &mut ViewContext<V>) + 'static,
3530 ) -> impl Fn(&mut WindowContext) {
3531 let view = view.downgrade();
3532 move |cx: &mut WindowContext| {
3533 view.update(cx, |view, cx| f(view, cx)).ok();
3534 }
3535 }
3536
3537 /// Register a callback that can interrupt the closing of the current window based the returned boolean.
3538 /// If the callback returns false, the window won't be closed.
3539 pub fn on_window_should_close(&mut self, f: impl Fn(&mut WindowContext) -> bool + 'static) {
3540 let mut this = self.to_async();
3541 self.window
3542 .platform_window
3543 .on_should_close(Box::new(move || this.update(|cx| f(cx)).unwrap_or(true)))
3544 }
3545
3546 /// Register an action listener on the window for the next frame. The type of action
3547 /// is determined by the first parameter of the given listener. When the next frame is rendered
3548 /// the listener will be cleared.
3549 ///
3550 /// This is a fairly low-level method, so prefer using action handlers on elements unless you have
3551 /// a specific need to register a global listener.
3552 pub fn on_action(
3553 &mut self,
3554 action_type: TypeId,
3555 listener: impl Fn(&dyn Any, DispatchPhase, &mut WindowContext) + 'static,
3556 ) {
3557 self.window
3558 .next_frame
3559 .dispatch_tree
3560 .on_action(action_type, Rc::new(listener));
3561 }
3562}
3563
3564#[cfg(target_os = "windows")]
3565impl WindowContext<'_> {
3566 /// Returns the raw HWND handle for the window.
3567 pub fn get_raw_handle(&self) -> windows::Win32::Foundation::HWND {
3568 self.window.platform_window.get_raw_handle()
3569 }
3570}
3571
3572impl Context for WindowContext<'_> {
3573 type Result<T> = T;
3574
3575 fn new_model<T>(&mut self, build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T) -> Model<T>
3576 where
3577 T: 'static,
3578 {
3579 let slot = self.app.entities.reserve();
3580 let model = build_model(&mut ModelContext::new(&mut *self.app, slot.downgrade()));
3581 self.entities.insert(slot, model)
3582 }
3583
3584 fn reserve_model<T: 'static>(&mut self) -> Self::Result<crate::Reservation<T>> {
3585 self.app.reserve_model()
3586 }
3587
3588 fn insert_model<T: 'static>(
3589 &mut self,
3590 reservation: crate::Reservation<T>,
3591 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
3592 ) -> Self::Result<Model<T>> {
3593 self.app.insert_model(reservation, build_model)
3594 }
3595
3596 fn update_model<T: 'static, R>(
3597 &mut self,
3598 model: &Model<T>,
3599 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
3600 ) -> R {
3601 let mut entity = self.entities.lease(model);
3602 let result = update(
3603 &mut *entity,
3604 &mut ModelContext::new(&mut *self.app, model.downgrade()),
3605 );
3606 self.entities.end_lease(entity);
3607 result
3608 }
3609
3610 fn read_model<T, R>(
3611 &self,
3612 handle: &Model<T>,
3613 read: impl FnOnce(&T, &AppContext) -> R,
3614 ) -> Self::Result<R>
3615 where
3616 T: 'static,
3617 {
3618 let entity = self.entities.read(handle);
3619 read(entity, &*self.app)
3620 }
3621
3622 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
3623 where
3624 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
3625 {
3626 if window == self.window.handle {
3627 let root_view = self.window.root_view.clone().unwrap();
3628 Ok(update(root_view, self))
3629 } else {
3630 window.update(self.app, update)
3631 }
3632 }
3633
3634 fn read_window<T, R>(
3635 &self,
3636 window: &WindowHandle<T>,
3637 read: impl FnOnce(View<T>, &AppContext) -> R,
3638 ) -> Result<R>
3639 where
3640 T: 'static,
3641 {
3642 if window.any_handle == self.window.handle {
3643 let root_view = self
3644 .window
3645 .root_view
3646 .clone()
3647 .unwrap()
3648 .downcast::<T>()
3649 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
3650 Ok(read(root_view, self))
3651 } else {
3652 self.app.read_window(window, read)
3653 }
3654 }
3655}
3656
3657impl VisualContext for WindowContext<'_> {
3658 fn new_view<V>(
3659 &mut self,
3660 build_view_state: impl FnOnce(&mut ViewContext<'_, V>) -> V,
3661 ) -> Self::Result<View<V>>
3662 where
3663 V: 'static + Render,
3664 {
3665 let slot = self.app.entities.reserve();
3666 let view = View {
3667 model: slot.clone(),
3668 };
3669 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
3670 let entity = build_view_state(&mut cx);
3671 cx.entities.insert(slot, entity);
3672
3673 // Non-generic part to avoid leaking SubscriberSet to invokers of `new_view`.
3674 fn notify_observers(cx: &mut WindowContext, tid: TypeId, view: AnyView) {
3675 cx.new_view_observers.clone().retain(&tid, |observer| {
3676 let any_view = view.clone();
3677 (observer)(any_view, cx);
3678 true
3679 });
3680 }
3681 notify_observers(self, TypeId::of::<V>(), AnyView::from(view.clone()));
3682
3683 view
3684 }
3685
3686 /// Updates the given view. Prefer calling [`View::update`] instead, which calls this method.
3687 fn update_view<T: 'static, R>(
3688 &mut self,
3689 view: &View<T>,
3690 update: impl FnOnce(&mut T, &mut ViewContext<'_, T>) -> R,
3691 ) -> Self::Result<R> {
3692 let mut lease = self.app.entities.lease(&view.model);
3693 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, view);
3694 let result = update(&mut *lease, &mut cx);
3695 cx.app.entities.end_lease(lease);
3696 result
3697 }
3698
3699 fn replace_root_view<V>(
3700 &mut self,
3701 build_view: impl FnOnce(&mut ViewContext<'_, V>) -> V,
3702 ) -> Self::Result<View<V>>
3703 where
3704 V: 'static + Render,
3705 {
3706 let view = self.new_view(build_view);
3707 self.window.root_view = Some(view.clone().into());
3708 self.refresh();
3709 view
3710 }
3711
3712 fn focus_view<V: crate::FocusableView>(&mut self, view: &View<V>) -> Self::Result<()> {
3713 self.update_view(view, |view, cx| {
3714 view.focus_handle(cx).clone().focus(cx);
3715 })
3716 }
3717
3718 fn dismiss_view<V>(&mut self, view: &View<V>) -> Self::Result<()>
3719 where
3720 V: ManagedView,
3721 {
3722 self.update_view(view, |_, cx| cx.emit(DismissEvent))
3723 }
3724}
3725
3726impl<'a> std::ops::Deref for WindowContext<'a> {
3727 type Target = AppContext;
3728
3729 fn deref(&self) -> &Self::Target {
3730 self.app
3731 }
3732}
3733
3734impl<'a> std::ops::DerefMut for WindowContext<'a> {
3735 fn deref_mut(&mut self) -> &mut Self::Target {
3736 self.app
3737 }
3738}
3739
3740impl<'a> Borrow<AppContext> for WindowContext<'a> {
3741 fn borrow(&self) -> &AppContext {
3742 self.app
3743 }
3744}
3745
3746impl<'a> BorrowMut<AppContext> for WindowContext<'a> {
3747 fn borrow_mut(&mut self) -> &mut AppContext {
3748 self.app
3749 }
3750}
3751
3752/// This trait contains functionality that is shared across [`ViewContext`] and [`WindowContext`]
3753pub trait BorrowWindow: BorrowMut<Window> + BorrowMut<AppContext> {
3754 #[doc(hidden)]
3755 fn app_mut(&mut self) -> &mut AppContext {
3756 self.borrow_mut()
3757 }
3758
3759 #[doc(hidden)]
3760 fn app(&self) -> &AppContext {
3761 self.borrow()
3762 }
3763
3764 #[doc(hidden)]
3765 fn window(&self) -> &Window {
3766 self.borrow()
3767 }
3768
3769 #[doc(hidden)]
3770 fn window_mut(&mut self) -> &mut Window {
3771 self.borrow_mut()
3772 }
3773}
3774
3775impl Borrow<Window> for WindowContext<'_> {
3776 fn borrow(&self) -> &Window {
3777 self.window
3778 }
3779}
3780
3781impl BorrowMut<Window> for WindowContext<'_> {
3782 fn borrow_mut(&mut self) -> &mut Window {
3783 self.window
3784 }
3785}
3786
3787impl<T> BorrowWindow for T where T: BorrowMut<AppContext> + BorrowMut<Window> {}
3788
3789/// Provides access to application state that is specialized for a particular [`View`].
3790/// Allows you to interact with focus, emit events, etc.
3791/// ViewContext also derefs to [`WindowContext`], giving you access to all of its methods as well.
3792/// When you call [`View::update`], you're passed a `&mut V` and an `&mut ViewContext<V>`.
3793pub struct ViewContext<'a, V> {
3794 window_cx: WindowContext<'a>,
3795 view: &'a View<V>,
3796}
3797
3798impl<V> Borrow<AppContext> for ViewContext<'_, V> {
3799 fn borrow(&self) -> &AppContext {
3800 &*self.window_cx.app
3801 }
3802}
3803
3804impl<V> BorrowMut<AppContext> for ViewContext<'_, V> {
3805 fn borrow_mut(&mut self) -> &mut AppContext {
3806 &mut *self.window_cx.app
3807 }
3808}
3809
3810impl<V> Borrow<Window> for ViewContext<'_, V> {
3811 fn borrow(&self) -> &Window {
3812 &*self.window_cx.window
3813 }
3814}
3815
3816impl<V> BorrowMut<Window> for ViewContext<'_, V> {
3817 fn borrow_mut(&mut self) -> &mut Window {
3818 &mut *self.window_cx.window
3819 }
3820}
3821
3822impl<'a, V: 'static> ViewContext<'a, V> {
3823 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window, view: &'a View<V>) -> Self {
3824 Self {
3825 window_cx: WindowContext::new(app, window),
3826 view,
3827 }
3828 }
3829
3830 /// Get the entity_id of this view.
3831 pub fn entity_id(&self) -> EntityId {
3832 self.view.entity_id()
3833 }
3834
3835 /// Get the view pointer underlying this context.
3836 pub fn view(&self) -> &View<V> {
3837 self.view
3838 }
3839
3840 /// Get the model underlying this view.
3841 pub fn model(&self) -> &Model<V> {
3842 &self.view.model
3843 }
3844
3845 /// Access the underlying window context.
3846 pub fn window_context(&mut self) -> &mut WindowContext<'a> {
3847 &mut self.window_cx
3848 }
3849
3850 /// Sets a given callback to be run on the next frame.
3851 pub fn on_next_frame(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static)
3852 where
3853 V: 'static,
3854 {
3855 let view = self.view().clone();
3856 self.window_cx.on_next_frame(move |cx| view.update(cx, f));
3857 }
3858
3859 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
3860 /// that are currently on the stack to be returned to the app.
3861 pub fn defer(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static) {
3862 let view = self.view().downgrade();
3863 self.window_cx.defer(move |cx| {
3864 view.update(cx, f).ok();
3865 });
3866 }
3867
3868 /// Observe another model or view for changes to its state, as tracked by [`ModelContext::notify`].
3869 pub fn observe<V2, E>(
3870 &mut self,
3871 entity: &E,
3872 mut on_notify: impl FnMut(&mut V, E, &mut ViewContext<'_, V>) + 'static,
3873 ) -> Subscription
3874 where
3875 V2: 'static,
3876 V: 'static,
3877 E: Entity<V2>,
3878 {
3879 let view = self.view().downgrade();
3880 let entity_id = entity.entity_id();
3881 let entity = entity.downgrade();
3882 let window_handle = self.window.handle;
3883 self.app.new_observer(
3884 entity_id,
3885 Box::new(move |cx| {
3886 window_handle
3887 .update(cx, |_, cx| {
3888 if let Some(handle) = E::upgrade_from(&entity) {
3889 view.update(cx, |this, cx| on_notify(this, handle, cx))
3890 .is_ok()
3891 } else {
3892 false
3893 }
3894 })
3895 .unwrap_or(false)
3896 }),
3897 )
3898 }
3899
3900 /// Subscribe to events emitted by another model or view.
3901 /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
3902 /// 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.
3903 pub fn subscribe<V2, E, Evt>(
3904 &mut self,
3905 entity: &E,
3906 mut on_event: impl FnMut(&mut V, E, &Evt, &mut ViewContext<'_, V>) + 'static,
3907 ) -> Subscription
3908 where
3909 V2: EventEmitter<Evt>,
3910 E: Entity<V2>,
3911 Evt: 'static,
3912 {
3913 let view = self.view().downgrade();
3914 let entity_id = entity.entity_id();
3915 let handle = entity.downgrade();
3916 let window_handle = self.window.handle;
3917 self.app.new_subscription(
3918 entity_id,
3919 (
3920 TypeId::of::<Evt>(),
3921 Box::new(move |event, cx| {
3922 window_handle
3923 .update(cx, |_, cx| {
3924 if let Some(handle) = E::upgrade_from(&handle) {
3925 let event = event.downcast_ref().expect("invalid event type");
3926 view.update(cx, |this, cx| on_event(this, handle, event, cx))
3927 .is_ok()
3928 } else {
3929 false
3930 }
3931 })
3932 .unwrap_or(false)
3933 }),
3934 ),
3935 )
3936 }
3937
3938 /// Register a callback to be invoked when the view is released.
3939 ///
3940 /// The callback receives a handle to the view's window. This handle may be
3941 /// invalid, if the window was closed before the view was released.
3942 pub fn on_release(
3943 &mut self,
3944 on_release: impl FnOnce(&mut V, AnyWindowHandle, &mut AppContext) + 'static,
3945 ) -> Subscription {
3946 let window_handle = self.window.handle;
3947 let (subscription, activate) = self.app.release_listeners.insert(
3948 self.view.model.entity_id,
3949 Box::new(move |this, cx| {
3950 let this = this.downcast_mut().expect("invalid entity type");
3951 on_release(this, window_handle, cx)
3952 }),
3953 );
3954 activate();
3955 subscription
3956 }
3957
3958 /// Register a callback to be invoked when the given Model or View is released.
3959 pub fn observe_release<V2, E>(
3960 &mut self,
3961 entity: &E,
3962 mut on_release: impl FnMut(&mut V, &mut V2, &mut ViewContext<'_, V>) + 'static,
3963 ) -> Subscription
3964 where
3965 V: 'static,
3966 V2: 'static,
3967 E: Entity<V2>,
3968 {
3969 let view = self.view().downgrade();
3970 let entity_id = entity.entity_id();
3971 let window_handle = self.window.handle;
3972 let (subscription, activate) = self.app.release_listeners.insert(
3973 entity_id,
3974 Box::new(move |entity, cx| {
3975 let entity = entity.downcast_mut().expect("invalid entity type");
3976 let _ = window_handle.update(cx, |_, cx| {
3977 view.update(cx, |this, cx| on_release(this, entity, cx))
3978 });
3979 }),
3980 );
3981 activate();
3982 subscription
3983 }
3984
3985 /// Indicate that this view has changed, which will invoke any observers and also mark the window as dirty.
3986 /// If this view or any of its ancestors are *cached*, notifying it will cause it or its ancestors to be redrawn.
3987 pub fn notify(&mut self) {
3988 self.window_cx.notify(self.view.entity_id());
3989 }
3990
3991 /// Register a callback to be invoked when the window is resized.
3992 pub fn observe_window_bounds(
3993 &mut self,
3994 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
3995 ) -> Subscription {
3996 let view = self.view.downgrade();
3997 let (subscription, activate) = self.window.bounds_observers.insert(
3998 (),
3999 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
4000 );
4001 activate();
4002 subscription
4003 }
4004
4005 /// Register a callback to be invoked when the window is activated or deactivated.
4006 pub fn observe_window_activation(
4007 &mut self,
4008 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4009 ) -> Subscription {
4010 let view = self.view.downgrade();
4011 let (subscription, activate) = self.window.activation_observers.insert(
4012 (),
4013 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
4014 );
4015 activate();
4016 subscription
4017 }
4018
4019 /// Registers a callback to be invoked when the window appearance changes.
4020 pub fn observe_window_appearance(
4021 &mut self,
4022 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4023 ) -> Subscription {
4024 let view = self.view.downgrade();
4025 let (subscription, activate) = self.window.appearance_observers.insert(
4026 (),
4027 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
4028 );
4029 activate();
4030 subscription
4031 }
4032
4033 /// Register a listener to be called when the given focus handle receives focus.
4034 /// Returns a subscription and persists until the subscription is dropped.
4035 pub fn on_focus(
4036 &mut self,
4037 handle: &FocusHandle,
4038 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4039 ) -> Subscription {
4040 let view = self.view.downgrade();
4041 let focus_id = handle.id;
4042 let (subscription, activate) =
4043 self.window.new_focus_listener(Box::new(move |event, cx| {
4044 view.update(cx, |view, cx| {
4045 if event.previous_focus_path.last() != Some(&focus_id)
4046 && event.current_focus_path.last() == Some(&focus_id)
4047 {
4048 listener(view, cx)
4049 }
4050 })
4051 .is_ok()
4052 }));
4053 self.app.defer(|_| activate());
4054 subscription
4055 }
4056
4057 /// Register a listener to be called when the given focus handle or one of its descendants receives focus.
4058 /// Returns a subscription and persists until the subscription is dropped.
4059 pub fn on_focus_in(
4060 &mut self,
4061 handle: &FocusHandle,
4062 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4063 ) -> Subscription {
4064 let view = self.view.downgrade();
4065 let focus_id = handle.id;
4066 let (subscription, activate) =
4067 self.window.new_focus_listener(Box::new(move |event, cx| {
4068 view.update(cx, |view, cx| {
4069 if !event.previous_focus_path.contains(&focus_id)
4070 && event.current_focus_path.contains(&focus_id)
4071 {
4072 listener(view, cx)
4073 }
4074 })
4075 .is_ok()
4076 }));
4077 self.app.defer(move |_| activate());
4078 subscription
4079 }
4080
4081 /// Register a listener to be called when the given focus handle loses focus.
4082 /// Returns a subscription and persists until the subscription is dropped.
4083 pub fn on_blur(
4084 &mut self,
4085 handle: &FocusHandle,
4086 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4087 ) -> Subscription {
4088 let view = self.view.downgrade();
4089 let focus_id = handle.id;
4090 let (subscription, activate) =
4091 self.window.new_focus_listener(Box::new(move |event, cx| {
4092 view.update(cx, |view, cx| {
4093 if event.previous_focus_path.last() == Some(&focus_id)
4094 && event.current_focus_path.last() != Some(&focus_id)
4095 {
4096 listener(view, cx)
4097 }
4098 })
4099 .is_ok()
4100 }));
4101 self.app.defer(move |_| activate());
4102 subscription
4103 }
4104
4105 /// Register a listener to be called when nothing in the window has focus.
4106 /// This typically happens when the node that was focused is removed from the tree,
4107 /// and this callback lets you chose a default place to restore the users focus.
4108 /// Returns a subscription and persists until the subscription is dropped.
4109 pub fn on_focus_lost(
4110 &mut self,
4111 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4112 ) -> Subscription {
4113 let view = self.view.downgrade();
4114 let (subscription, activate) = self.window.focus_lost_listeners.insert(
4115 (),
4116 Box::new(move |cx| view.update(cx, |view, cx| listener(view, cx)).is_ok()),
4117 );
4118 activate();
4119 subscription
4120 }
4121
4122 /// Register a listener to be called when the given focus handle or one of its descendants loses focus.
4123 /// Returns a subscription and persists until the subscription is dropped.
4124 pub fn on_focus_out(
4125 &mut self,
4126 handle: &FocusHandle,
4127 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4128 ) -> Subscription {
4129 let view = self.view.downgrade();
4130 let focus_id = handle.id;
4131 let (subscription, activate) =
4132 self.window.new_focus_listener(Box::new(move |event, cx| {
4133 view.update(cx, |view, cx| {
4134 if event.previous_focus_path.contains(&focus_id)
4135 && !event.current_focus_path.contains(&focus_id)
4136 {
4137 listener(view, cx)
4138 }
4139 })
4140 .is_ok()
4141 }));
4142 self.app.defer(move |_| activate());
4143 subscription
4144 }
4145
4146 /// Schedule a future to be run asynchronously.
4147 /// The given callback is invoked with a [`WeakView<V>`] to avoid leaking the view for a long-running process.
4148 /// It's also given an [`AsyncWindowContext`], which can be used to access the state of the view across await points.
4149 /// The returned future will be polled on the main thread.
4150 pub fn spawn<Fut, R>(
4151 &mut self,
4152 f: impl FnOnce(WeakView<V>, AsyncWindowContext) -> Fut,
4153 ) -> Task<R>
4154 where
4155 R: 'static,
4156 Fut: Future<Output = R> + 'static,
4157 {
4158 let view = self.view().downgrade();
4159 self.window_cx.spawn(|cx| f(view, cx))
4160 }
4161
4162 /// Register a callback to be invoked when the given global state changes.
4163 pub fn observe_global<G: Global>(
4164 &mut self,
4165 mut f: impl FnMut(&mut V, &mut ViewContext<'_, V>) + 'static,
4166 ) -> Subscription {
4167 let window_handle = self.window.handle;
4168 let view = self.view().downgrade();
4169 let (subscription, activate) = self.global_observers.insert(
4170 TypeId::of::<G>(),
4171 Box::new(move |cx| {
4172 window_handle
4173 .update(cx, |_, cx| view.update(cx, |view, cx| f(view, cx)).is_ok())
4174 .unwrap_or(false)
4175 }),
4176 );
4177 self.app.defer(move |_| activate());
4178 subscription
4179 }
4180
4181 /// Register a callback to be invoked when the given Action type is dispatched to the window.
4182 pub fn on_action(
4183 &mut self,
4184 action_type: TypeId,
4185 listener: impl Fn(&mut V, &dyn Any, DispatchPhase, &mut ViewContext<V>) + 'static,
4186 ) {
4187 let handle = self.view().clone();
4188 self.window_cx
4189 .on_action(action_type, move |action, phase, cx| {
4190 handle.update(cx, |view, cx| {
4191 listener(view, action, phase, cx);
4192 })
4193 });
4194 }
4195
4196 /// Emit an event to be handled any other views that have subscribed via [ViewContext::subscribe].
4197 pub fn emit<Evt>(&mut self, event: Evt)
4198 where
4199 Evt: 'static,
4200 V: EventEmitter<Evt>,
4201 {
4202 let emitter = self.view.model.entity_id;
4203 self.app.push_effect(Effect::Emit {
4204 emitter,
4205 event_type: TypeId::of::<Evt>(),
4206 event: Box::new(event),
4207 });
4208 }
4209
4210 /// Move focus to the current view, assuming it implements [`FocusableView`].
4211 pub fn focus_self(&mut self)
4212 where
4213 V: FocusableView,
4214 {
4215 self.defer(|view, cx| view.focus_handle(cx).focus(cx))
4216 }
4217
4218 /// Convenience method for accessing view state in an event callback.
4219 ///
4220 /// Many GPUI callbacks take the form of `Fn(&E, &mut WindowContext)`,
4221 /// but it's often useful to be able to access view state in these
4222 /// callbacks. This method provides a convenient way to do so.
4223 pub fn listener<E>(
4224 &self,
4225 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
4226 ) -> impl Fn(&E, &mut WindowContext) + 'static {
4227 let view = self.view().downgrade();
4228 move |e: &E, cx: &mut WindowContext| {
4229 view.update(cx, |view, cx| f(view, e, cx)).ok();
4230 }
4231 }
4232}
4233
4234impl<V> Context for ViewContext<'_, V> {
4235 type Result<U> = U;
4236
4237 fn new_model<T: 'static>(
4238 &mut self,
4239 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
4240 ) -> Model<T> {
4241 self.window_cx.new_model(build_model)
4242 }
4243
4244 fn reserve_model<T: 'static>(&mut self) -> Self::Result<crate::Reservation<T>> {
4245 self.window_cx.reserve_model()
4246 }
4247
4248 fn insert_model<T: 'static>(
4249 &mut self,
4250 reservation: crate::Reservation<T>,
4251 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
4252 ) -> Self::Result<Model<T>> {
4253 self.window_cx.insert_model(reservation, build_model)
4254 }
4255
4256 fn update_model<T: 'static, R>(
4257 &mut self,
4258 model: &Model<T>,
4259 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
4260 ) -> R {
4261 self.window_cx.update_model(model, update)
4262 }
4263
4264 fn read_model<T, R>(
4265 &self,
4266 handle: &Model<T>,
4267 read: impl FnOnce(&T, &AppContext) -> R,
4268 ) -> Self::Result<R>
4269 where
4270 T: 'static,
4271 {
4272 self.window_cx.read_model(handle, read)
4273 }
4274
4275 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
4276 where
4277 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
4278 {
4279 self.window_cx.update_window(window, update)
4280 }
4281
4282 fn read_window<T, R>(
4283 &self,
4284 window: &WindowHandle<T>,
4285 read: impl FnOnce(View<T>, &AppContext) -> R,
4286 ) -> Result<R>
4287 where
4288 T: 'static,
4289 {
4290 self.window_cx.read_window(window, read)
4291 }
4292}
4293
4294impl<V: 'static> VisualContext for ViewContext<'_, V> {
4295 fn new_view<W: Render + 'static>(
4296 &mut self,
4297 build_view_state: impl FnOnce(&mut ViewContext<'_, W>) -> W,
4298 ) -> Self::Result<View<W>> {
4299 self.window_cx.new_view(build_view_state)
4300 }
4301
4302 fn update_view<V2: 'static, R>(
4303 &mut self,
4304 view: &View<V2>,
4305 update: impl FnOnce(&mut V2, &mut ViewContext<'_, V2>) -> R,
4306 ) -> Self::Result<R> {
4307 self.window_cx.update_view(view, update)
4308 }
4309
4310 fn replace_root_view<W>(
4311 &mut self,
4312 build_view: impl FnOnce(&mut ViewContext<'_, W>) -> W,
4313 ) -> Self::Result<View<W>>
4314 where
4315 W: 'static + Render,
4316 {
4317 self.window_cx.replace_root_view(build_view)
4318 }
4319
4320 fn focus_view<W: FocusableView>(&mut self, view: &View<W>) -> Self::Result<()> {
4321 self.window_cx.focus_view(view)
4322 }
4323
4324 fn dismiss_view<W: ManagedView>(&mut self, view: &View<W>) -> Self::Result<()> {
4325 self.window_cx.dismiss_view(view)
4326 }
4327}
4328
4329impl<'a, V> std::ops::Deref for ViewContext<'a, V> {
4330 type Target = WindowContext<'a>;
4331
4332 fn deref(&self) -> &Self::Target {
4333 &self.window_cx
4334 }
4335}
4336
4337impl<'a, V> std::ops::DerefMut for ViewContext<'a, V> {
4338 fn deref_mut(&mut self) -> &mut Self::Target {
4339 &mut self.window_cx
4340 }
4341}
4342
4343// #[derive(Clone, Copy, Eq, PartialEq, Hash)]
4344slotmap::new_key_type! {
4345 /// A unique identifier for a window.
4346 pub struct WindowId;
4347}
4348
4349impl WindowId {
4350 /// Converts this window ID to a `u64`.
4351 pub fn as_u64(&self) -> u64 {
4352 self.0.as_ffi()
4353 }
4354}
4355
4356/// A handle to a window with a specific root view type.
4357/// Note that this does not keep the window alive on its own.
4358#[derive(Deref, DerefMut)]
4359pub struct WindowHandle<V> {
4360 #[deref]
4361 #[deref_mut]
4362 pub(crate) any_handle: AnyWindowHandle,
4363 state_type: PhantomData<V>,
4364}
4365
4366impl<V: 'static + Render> WindowHandle<V> {
4367 /// Creates a new handle from a window ID.
4368 /// This does not check if the root type of the window is `V`.
4369 pub fn new(id: WindowId) -> Self {
4370 WindowHandle {
4371 any_handle: AnyWindowHandle {
4372 id,
4373 state_type: TypeId::of::<V>(),
4374 },
4375 state_type: PhantomData,
4376 }
4377 }
4378
4379 /// Get the root view out of this window.
4380 ///
4381 /// This will fail if the window is closed or if the root view's type does not match `V`.
4382 pub fn root<C>(&self, cx: &mut C) -> Result<View<V>>
4383 where
4384 C: Context,
4385 {
4386 Flatten::flatten(cx.update_window(self.any_handle, |root_view, _| {
4387 root_view
4388 .downcast::<V>()
4389 .map_err(|_| anyhow!("the type of the window's root view has changed"))
4390 }))
4391 }
4392
4393 /// Updates the root view of this window.
4394 ///
4395 /// This will fail if the window has been closed or if the root view's type does not match
4396 pub fn update<C, R>(
4397 &self,
4398 cx: &mut C,
4399 update: impl FnOnce(&mut V, &mut ViewContext<'_, V>) -> R,
4400 ) -> Result<R>
4401 where
4402 C: Context,
4403 {
4404 cx.update_window(self.any_handle, |root_view, cx| {
4405 let view = root_view
4406 .downcast::<V>()
4407 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
4408 Ok(cx.update_view(&view, update))
4409 })?
4410 }
4411
4412 /// Read the root view out of this window.
4413 ///
4414 /// This will fail if the window is closed or if the root view's type does not match `V`.
4415 pub fn read<'a>(&self, cx: &'a AppContext) -> Result<&'a V> {
4416 let x = cx
4417 .windows
4418 .get(self.id)
4419 .and_then(|window| {
4420 window
4421 .as_ref()
4422 .and_then(|window| window.root_view.clone())
4423 .map(|root_view| root_view.downcast::<V>())
4424 })
4425 .ok_or_else(|| anyhow!("window not found"))?
4426 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
4427
4428 Ok(x.read(cx))
4429 }
4430
4431 /// Read the root view out of this window, with a callback
4432 ///
4433 /// This will fail if the window is closed or if the root view's type does not match `V`.
4434 pub fn read_with<C, R>(&self, cx: &C, read_with: impl FnOnce(&V, &AppContext) -> R) -> Result<R>
4435 where
4436 C: Context,
4437 {
4438 cx.read_window(self, |root_view, cx| read_with(root_view.read(cx), cx))
4439 }
4440
4441 /// Read the root view pointer off of this window.
4442 ///
4443 /// This will fail if the window is closed or if the root view's type does not match `V`.
4444 pub fn root_view<C>(&self, cx: &C) -> Result<View<V>>
4445 where
4446 C: Context,
4447 {
4448 cx.read_window(self, |root_view, _cx| root_view.clone())
4449 }
4450
4451 /// Check if this window is 'active'.
4452 ///
4453 /// Will return `None` if the window is closed or currently
4454 /// borrowed.
4455 pub fn is_active(&self, cx: &mut AppContext) -> Option<bool> {
4456 cx.update_window(self.any_handle, |_, cx| cx.is_window_active())
4457 .ok()
4458 }
4459}
4460
4461impl<V> Copy for WindowHandle<V> {}
4462
4463impl<V> Clone for WindowHandle<V> {
4464 fn clone(&self) -> Self {
4465 *self
4466 }
4467}
4468
4469impl<V> PartialEq for WindowHandle<V> {
4470 fn eq(&self, other: &Self) -> bool {
4471 self.any_handle == other.any_handle
4472 }
4473}
4474
4475impl<V> Eq for WindowHandle<V> {}
4476
4477impl<V> Hash for WindowHandle<V> {
4478 fn hash<H: Hasher>(&self, state: &mut H) {
4479 self.any_handle.hash(state);
4480 }
4481}
4482
4483impl<V: 'static> From<WindowHandle<V>> for AnyWindowHandle {
4484 fn from(val: WindowHandle<V>) -> Self {
4485 val.any_handle
4486 }
4487}
4488
4489unsafe impl<V> Send for WindowHandle<V> {}
4490unsafe impl<V> Sync for WindowHandle<V> {}
4491
4492/// A handle to a window with any root view type, which can be downcast to a window with a specific root view type.
4493#[derive(Copy, Clone, PartialEq, Eq, Hash)]
4494pub struct AnyWindowHandle {
4495 pub(crate) id: WindowId,
4496 state_type: TypeId,
4497}
4498
4499impl AnyWindowHandle {
4500 /// Get the ID of this window.
4501 pub fn window_id(&self) -> WindowId {
4502 self.id
4503 }
4504
4505 /// Attempt to convert this handle to a window handle with a specific root view type.
4506 /// If the types do not match, this will return `None`.
4507 pub fn downcast<T: 'static>(&self) -> Option<WindowHandle<T>> {
4508 if TypeId::of::<T>() == self.state_type {
4509 Some(WindowHandle {
4510 any_handle: *self,
4511 state_type: PhantomData,
4512 })
4513 } else {
4514 None
4515 }
4516 }
4517
4518 /// Updates the state of the root view of this window.
4519 ///
4520 /// This will fail if the window has been closed.
4521 pub fn update<C, R>(
4522 self,
4523 cx: &mut C,
4524 update: impl FnOnce(AnyView, &mut WindowContext<'_>) -> R,
4525 ) -> Result<R>
4526 where
4527 C: Context,
4528 {
4529 cx.update_window(self, update)
4530 }
4531
4532 /// Read the state of the root view of this window.
4533 ///
4534 /// This will fail if the window has been closed.
4535 pub fn read<T, C, R>(self, cx: &C, read: impl FnOnce(View<T>, &AppContext) -> R) -> Result<R>
4536 where
4537 C: Context,
4538 T: 'static,
4539 {
4540 let view = self
4541 .downcast::<T>()
4542 .context("the type of the window's root view has changed")?;
4543
4544 cx.read_window(&view, read)
4545 }
4546}
4547
4548/// An identifier for an [`Element`](crate::Element).
4549///
4550/// Can be constructed with a string, a number, or both, as well
4551/// as other internal representations.
4552#[derive(Clone, Debug, Eq, PartialEq, Hash)]
4553pub enum ElementId {
4554 /// The ID of a View element
4555 View(EntityId),
4556 /// An integer ID.
4557 Integer(usize),
4558 /// A string based ID.
4559 Name(SharedString),
4560 /// A UUID.
4561 Uuid(Uuid),
4562 /// An ID that's equated with a focus handle.
4563 FocusHandle(FocusId),
4564 /// A combination of a name and an integer.
4565 NamedInteger(SharedString, usize),
4566}
4567
4568impl Display for ElementId {
4569 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
4570 match self {
4571 ElementId::View(entity_id) => write!(f, "view-{}", entity_id)?,
4572 ElementId::Integer(ix) => write!(f, "{}", ix)?,
4573 ElementId::Name(name) => write!(f, "{}", name)?,
4574 ElementId::FocusHandle(_) => write!(f, "FocusHandle")?,
4575 ElementId::NamedInteger(s, i) => write!(f, "{}-{}", s, i)?,
4576 ElementId::Uuid(uuid) => write!(f, "{}", uuid)?,
4577 }
4578
4579 Ok(())
4580 }
4581}
4582
4583impl TryInto<SharedString> for ElementId {
4584 type Error = anyhow::Error;
4585
4586 fn try_into(self) -> anyhow::Result<SharedString> {
4587 if let ElementId::Name(name) = self {
4588 Ok(name)
4589 } else {
4590 Err(anyhow!("element id is not string"))
4591 }
4592 }
4593}
4594
4595impl From<usize> for ElementId {
4596 fn from(id: usize) -> Self {
4597 ElementId::Integer(id)
4598 }
4599}
4600
4601impl From<i32> for ElementId {
4602 fn from(id: i32) -> Self {
4603 Self::Integer(id as usize)
4604 }
4605}
4606
4607impl From<SharedString> for ElementId {
4608 fn from(name: SharedString) -> Self {
4609 ElementId::Name(name)
4610 }
4611}
4612
4613impl From<&'static str> for ElementId {
4614 fn from(name: &'static str) -> Self {
4615 ElementId::Name(name.into())
4616 }
4617}
4618
4619impl<'a> From<&'a FocusHandle> for ElementId {
4620 fn from(handle: &'a FocusHandle) -> Self {
4621 ElementId::FocusHandle(handle.id)
4622 }
4623}
4624
4625impl From<(&'static str, EntityId)> for ElementId {
4626 fn from((name, id): (&'static str, EntityId)) -> Self {
4627 ElementId::NamedInteger(name.into(), id.as_u64() as usize)
4628 }
4629}
4630
4631impl From<(&'static str, usize)> for ElementId {
4632 fn from((name, id): (&'static str, usize)) -> Self {
4633 ElementId::NamedInteger(name.into(), id)
4634 }
4635}
4636
4637impl From<(&'static str, u64)> for ElementId {
4638 fn from((name, id): (&'static str, u64)) -> Self {
4639 ElementId::NamedInteger(name.into(), id as usize)
4640 }
4641}
4642
4643impl From<Uuid> for ElementId {
4644 fn from(value: Uuid) -> Self {
4645 Self::Uuid(value)
4646 }
4647}
4648
4649impl From<(&'static str, u32)> for ElementId {
4650 fn from((name, id): (&'static str, u32)) -> Self {
4651 ElementId::NamedInteger(name.into(), id as usize)
4652 }
4653}
4654
4655/// A rectangle to be rendered in the window at the given position and size.
4656/// Passed as an argument [`WindowContext::paint_quad`].
4657#[derive(Clone)]
4658pub struct PaintQuad {
4659 /// The bounds of the quad within the window.
4660 pub bounds: Bounds<Pixels>,
4661 /// The radii of the quad's corners.
4662 pub corner_radii: Corners<Pixels>,
4663 /// The background color of the quad.
4664 pub background: Hsla,
4665 /// The widths of the quad's borders.
4666 pub border_widths: Edges<Pixels>,
4667 /// The color of the quad's borders.
4668 pub border_color: Hsla,
4669}
4670
4671impl PaintQuad {
4672 /// Sets the corner radii of the quad.
4673 pub fn corner_radii(self, corner_radii: impl Into<Corners<Pixels>>) -> Self {
4674 PaintQuad {
4675 corner_radii: corner_radii.into(),
4676 ..self
4677 }
4678 }
4679
4680 /// Sets the border widths of the quad.
4681 pub fn border_widths(self, border_widths: impl Into<Edges<Pixels>>) -> Self {
4682 PaintQuad {
4683 border_widths: border_widths.into(),
4684 ..self
4685 }
4686 }
4687
4688 /// Sets the border color of the quad.
4689 pub fn border_color(self, border_color: impl Into<Hsla>) -> Self {
4690 PaintQuad {
4691 border_color: border_color.into(),
4692 ..self
4693 }
4694 }
4695
4696 /// Sets the background color of the quad.
4697 pub fn background(self, background: impl Into<Hsla>) -> Self {
4698 PaintQuad {
4699 background: background.into(),
4700 ..self
4701 }
4702 }
4703}
4704
4705/// Creates a quad with the given parameters.
4706pub fn quad(
4707 bounds: Bounds<Pixels>,
4708 corner_radii: impl Into<Corners<Pixels>>,
4709 background: impl Into<Hsla>,
4710 border_widths: impl Into<Edges<Pixels>>,
4711 border_color: impl Into<Hsla>,
4712) -> PaintQuad {
4713 PaintQuad {
4714 bounds,
4715 corner_radii: corner_radii.into(),
4716 background: background.into(),
4717 border_widths: border_widths.into(),
4718 border_color: border_color.into(),
4719 }
4720}
4721
4722/// Creates a filled quad with the given bounds and background color.
4723pub fn fill(bounds: impl Into<Bounds<Pixels>>, background: impl Into<Hsla>) -> PaintQuad {
4724 PaintQuad {
4725 bounds: bounds.into(),
4726 corner_radii: (0.).into(),
4727 background: background.into(),
4728 border_widths: (0.).into(),
4729 border_color: transparent_black(),
4730 }
4731}
4732
4733/// Creates a rectangle outline with the given bounds, border color, and a 1px border width
4734pub fn outline(bounds: impl Into<Bounds<Pixels>>, border_color: impl Into<Hsla>) -> PaintQuad {
4735 PaintQuad {
4736 bounds: bounds.into(),
4737 corner_radii: (0.).into(),
4738 background: transparent_black(),
4739 border_widths: (1.).into(),
4740 border_color: border_color.into(),
4741 }
4742}