1use crate::{
2 hash, point, prelude::*, px, size, transparent_black, Action, AnyDrag, AnyElement, AnyTooltip,
3 AnyView, AppContext, Arena, Asset, AsyncWindowContext, AvailableSpace, Bounds, BoxShadow,
4 Context, Corners, CursorStyle, DevicePixels, DispatchActionListener, DispatchNodeId,
5 DispatchTree, DisplayId, Edges, Effect, Entity, EntityId, EventEmitter, FileDropEvent, Flatten,
6 FontId, Global, GlobalElementId, GlyphId, Hsla, ImageData, InputHandler, IsZero, KeyBinding,
7 KeyContext, KeyDownEvent, KeyEvent, KeyMatch, KeymatchResult, Keystroke, KeystrokeEvent,
8 LayoutId, LineLayoutIndex, Model, ModelContext, Modifiers, ModifiersChangedEvent,
9 MonochromeSprite, MouseButton, MouseEvent, MouseMoveEvent, MouseUpEvent, Path, Pixels,
10 PlatformAtlas, PlatformDisplay, PlatformInput, PlatformInputHandler, PlatformWindow, Point,
11 PolychromeSprite, PromptLevel, Quad, Render, RenderGlyphParams, RenderImageParams,
12 RenderSvgParams, ScaledPixels, Scene, Shadow, SharedString, Size, StrikethroughStyle, Style,
13 SubscriberSet, Subscription, TaffyLayoutEngine, Task, TextStyle, TextStyleRefinement,
14 TransformationMatrix, Underline, UnderlineStyle, View, VisualContext, WeakView,
15 WindowAppearance, WindowBackgroundAppearance, WindowBounds, WindowOptions, WindowParams,
16 WindowTextSystem, SUBPIXEL_VARIANTS,
17};
18use anyhow::{anyhow, Context as _, Result};
19use collections::{FxHashMap, FxHashSet};
20use derive_more::{Deref, DerefMut};
21use futures::channel::oneshot;
22use futures::{future::Shared, FutureExt};
23#[cfg(target_os = "macos")]
24use media::core_video::CVImageBuffer;
25use parking_lot::RwLock;
26use refineable::Refineable;
27use slotmap::SlotMap;
28use smallvec::SmallVec;
29use std::{
30 any::{Any, TypeId},
31 borrow::{Borrow, BorrowMut, Cow},
32 cell::{Cell, RefCell},
33 cmp,
34 fmt::{Debug, Display},
35 future::Future,
36 hash::{Hash, Hasher},
37 marker::PhantomData,
38 mem,
39 ops::Range,
40 rc::Rc,
41 sync::{
42 atomic::{AtomicUsize, Ordering::SeqCst},
43 Arc, Weak,
44 },
45 time::{Duration, Instant},
46};
47use util::post_inc;
48use util::{measure, ResultExt};
49use uuid::Uuid;
50
51mod prompts;
52
53pub use prompts::*;
54
55pub(crate) const DEFAULT_WINDOW_SIZE: Size<DevicePixels> =
56 size(DevicePixels(1024), DevicePixels(700));
57
58/// Represents the two different phases when dispatching events.
59#[derive(Default, Copy, Clone, Debug, Eq, PartialEq)]
60pub enum DispatchPhase {
61 /// After the capture phase comes the bubble phase, in which mouse event listeners are
62 /// invoked front to back and keyboard event listeners are invoked from the focused element
63 /// to the root of the element tree. This is the phase you'll most commonly want to use when
64 /// registering event listeners.
65 #[default]
66 Bubble,
67 /// During the initial capture phase, mouse event listeners are invoked back to front, and keyboard
68 /// listeners are invoked from the root of the tree downward toward the focused element. This phase
69 /// is used for special purposes such as clearing the "pressed" state for click events. If
70 /// you stop event propagation during this phase, you need to know what you're doing. Handlers
71 /// outside of the immediate region may rely on detecting non-local events during this phase.
72 Capture,
73}
74
75impl DispatchPhase {
76 /// Returns true if this represents the "bubble" phase.
77 pub fn bubble(self) -> bool {
78 self == DispatchPhase::Bubble
79 }
80
81 /// Returns true if this represents the "capture" phase.
82 pub fn capture(self) -> bool {
83 self == DispatchPhase::Capture
84 }
85}
86
87type AnyObserver = Box<dyn FnMut(&mut WindowContext) -> bool + 'static>;
88
89type AnyWindowFocusListener = Box<dyn FnMut(&FocusEvent, &mut WindowContext) -> bool + 'static>;
90
91struct FocusEvent {
92 previous_focus_path: SmallVec<[FocusId; 8]>,
93 current_focus_path: SmallVec<[FocusId; 8]>,
94}
95
96slotmap::new_key_type! {
97 /// A globally unique identifier for a focusable element.
98 pub struct FocusId;
99}
100
101thread_local! {
102 /// 8MB wasn't quite enough...
103 pub(crate) static ELEMENT_ARENA: RefCell<Arena> = RefCell::new(Arena::new(32 * 1024 * 1024));
104}
105
106impl FocusId {
107 /// Obtains whether the element associated with this handle is currently focused.
108 pub fn is_focused(&self, cx: &WindowContext) -> bool {
109 cx.window.focus == Some(*self)
110 }
111
112 /// Obtains whether the element associated with this handle contains the focused
113 /// element or is itself focused.
114 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
115 cx.focused()
116 .map_or(false, |focused| self.contains(focused.id, cx))
117 }
118
119 /// Obtains whether the element associated with this handle is contained within the
120 /// focused element or is itself focused.
121 pub fn within_focused(&self, cx: &WindowContext) -> bool {
122 let focused = cx.focused();
123 focused.map_or(false, |focused| focused.id.contains(*self, cx))
124 }
125
126 /// Obtains whether this handle contains the given handle in the most recently rendered frame.
127 pub(crate) fn contains(&self, other: Self, cx: &WindowContext) -> bool {
128 cx.window
129 .rendered_frame
130 .dispatch_tree
131 .focus_contains(*self, other)
132 }
133}
134
135/// A handle which can be used to track and manipulate the focused element in a window.
136pub struct FocusHandle {
137 pub(crate) id: FocusId,
138 handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
139}
140
141impl std::fmt::Debug for FocusHandle {
142 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
143 f.write_fmt(format_args!("FocusHandle({:?})", self.id))
144 }
145}
146
147impl FocusHandle {
148 pub(crate) fn new(handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>) -> Self {
149 let id = handles.write().insert(AtomicUsize::new(1));
150 Self {
151 id,
152 handles: handles.clone(),
153 }
154 }
155
156 pub(crate) fn for_id(
157 id: FocusId,
158 handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
159 ) -> Option<Self> {
160 let lock = handles.read();
161 let ref_count = lock.get(id)?;
162 if ref_count.load(SeqCst) == 0 {
163 None
164 } else {
165 ref_count.fetch_add(1, SeqCst);
166 Some(Self {
167 id,
168 handles: handles.clone(),
169 })
170 }
171 }
172
173 /// Converts this focus handle into a weak variant, which does not prevent it from being released.
174 pub fn downgrade(&self) -> WeakFocusHandle {
175 WeakFocusHandle {
176 id: self.id,
177 handles: Arc::downgrade(&self.handles),
178 }
179 }
180
181 /// Moves the focus to the element associated with this handle.
182 pub fn focus(&self, cx: &mut WindowContext) {
183 cx.focus(self)
184 }
185
186 /// Obtains whether the element associated with this handle is currently focused.
187 pub fn is_focused(&self, cx: &WindowContext) -> bool {
188 self.id.is_focused(cx)
189 }
190
191 /// Obtains whether the element associated with this handle contains the focused
192 /// element or is itself focused.
193 pub fn contains_focused(&self, cx: &WindowContext) -> bool {
194 self.id.contains_focused(cx)
195 }
196
197 /// Obtains whether the element associated with this handle is contained within the
198 /// focused element or is itself focused.
199 pub fn within_focused(&self, cx: &WindowContext) -> bool {
200 self.id.within_focused(cx)
201 }
202
203 /// Obtains whether this handle contains the given handle in the most recently rendered frame.
204 pub fn contains(&self, other: &Self, cx: &WindowContext) -> bool {
205 self.id.contains(other.id, cx)
206 }
207
208 /// Dispatch an action on the element that rendered this focus handle
209 pub fn dispatch_action(&self, action: &dyn Action, cx: &mut WindowContext) {
210 if let Some(node_id) = cx
211 .window
212 .rendered_frame
213 .dispatch_tree
214 .focusable_node_id(self.id)
215 {
216 cx.dispatch_action_on_node(node_id, action)
217 }
218 }
219}
220
221impl Clone for FocusHandle {
222 fn clone(&self) -> Self {
223 Self::for_id(self.id, &self.handles).unwrap()
224 }
225}
226
227impl PartialEq for FocusHandle {
228 fn eq(&self, other: &Self) -> bool {
229 self.id == other.id
230 }
231}
232
233impl Eq for FocusHandle {}
234
235impl Drop for FocusHandle {
236 fn drop(&mut self) {
237 self.handles
238 .read()
239 .get(self.id)
240 .unwrap()
241 .fetch_sub(1, SeqCst);
242 }
243}
244
245/// A weak reference to a focus handle.
246#[derive(Clone, Debug)]
247pub struct WeakFocusHandle {
248 pub(crate) id: FocusId,
249 handles: Weak<RwLock<SlotMap<FocusId, AtomicUsize>>>,
250}
251
252impl WeakFocusHandle {
253 /// Attempts to upgrade the [WeakFocusHandle] to a [FocusHandle].
254 pub fn upgrade(&self) -> Option<FocusHandle> {
255 let handles = self.handles.upgrade()?;
256 FocusHandle::for_id(self.id, &handles)
257 }
258}
259
260impl PartialEq for WeakFocusHandle {
261 fn eq(&self, other: &WeakFocusHandle) -> bool {
262 self.id == other.id
263 }
264}
265
266impl Eq for WeakFocusHandle {}
267
268impl PartialEq<FocusHandle> for WeakFocusHandle {
269 fn eq(&self, other: &FocusHandle) -> bool {
270 self.id == other.id
271 }
272}
273
274impl PartialEq<WeakFocusHandle> for FocusHandle {
275 fn eq(&self, other: &WeakFocusHandle) -> bool {
276 self.id == other.id
277 }
278}
279
280/// FocusableView allows users of your view to easily
281/// focus it (using cx.focus_view(view))
282pub trait FocusableView: 'static + Render {
283 /// Returns the focus handle associated with this view.
284 fn focus_handle(&self, cx: &AppContext) -> FocusHandle;
285}
286
287/// ManagedView is a view (like a Modal, Popover, Menu, etc.)
288/// where the lifecycle of the view is handled by another view.
289pub trait ManagedView: FocusableView + EventEmitter<DismissEvent> {}
290
291impl<M: FocusableView + EventEmitter<DismissEvent>> ManagedView for M {}
292
293/// Emitted by implementers of [`ManagedView`] to indicate the view should be dismissed, such as when a view is presented as a modal.
294pub struct DismissEvent;
295
296type FrameCallback = Box<dyn FnOnce(&mut WindowContext)>;
297
298pub(crate) type AnyMouseListener =
299 Box<dyn FnMut(&dyn Any, DispatchPhase, &mut WindowContext) + 'static>;
300
301#[derive(Clone)]
302pub(crate) struct CursorStyleRequest {
303 pub(crate) hitbox_id: HitboxId,
304 pub(crate) style: CursorStyle,
305}
306
307/// An identifier for a [Hitbox].
308#[derive(Copy, Clone, Debug, Default, Eq, PartialEq)]
309pub struct HitboxId(usize);
310
311impl HitboxId {
312 /// Checks if the hitbox with this id is currently hovered.
313 pub fn is_hovered(&self, cx: &WindowContext) -> bool {
314 cx.window.mouse_hit_test.0.contains(self)
315 }
316}
317
318/// A rectangular region that potentially blocks hitboxes inserted prior.
319/// See [WindowContext::insert_hitbox] for more details.
320#[derive(Clone, Debug, Deref)]
321pub struct Hitbox {
322 /// A unique identifier for the hitbox.
323 pub id: HitboxId,
324 /// The bounds of the hitbox.
325 #[deref]
326 pub bounds: Bounds<Pixels>,
327 /// The content mask when the hitbox was inserted.
328 pub content_mask: ContentMask<Pixels>,
329 /// Whether the hitbox occludes other hitboxes inserted prior.
330 pub opaque: bool,
331}
332
333impl Hitbox {
334 /// Checks if the hitbox is currently hovered.
335 pub fn is_hovered(&self, cx: &WindowContext) -> bool {
336 self.id.is_hovered(cx)
337 }
338}
339
340#[derive(Default, Eq, PartialEq)]
341pub(crate) struct HitTest(SmallVec<[HitboxId; 8]>);
342
343/// An identifier for a tooltip.
344#[derive(Copy, Clone, Debug, Default, Eq, PartialEq)]
345pub struct TooltipId(usize);
346
347impl TooltipId {
348 /// Checks if the tooltip is currently hovered.
349 pub fn is_hovered(&self, cx: &WindowContext) -> bool {
350 cx.window
351 .tooltip_bounds
352 .as_ref()
353 .map_or(false, |tooltip_bounds| {
354 tooltip_bounds.id == *self && tooltip_bounds.bounds.contains(&cx.mouse_position())
355 })
356 }
357}
358
359pub(crate) struct TooltipBounds {
360 id: TooltipId,
361 bounds: Bounds<Pixels>,
362}
363
364#[derive(Clone)]
365pub(crate) struct TooltipRequest {
366 id: TooltipId,
367 tooltip: AnyTooltip,
368}
369
370pub(crate) struct DeferredDraw {
371 priority: usize,
372 parent_node: DispatchNodeId,
373 element_id_stack: SmallVec<[ElementId; 32]>,
374 text_style_stack: Vec<TextStyleRefinement>,
375 element: Option<AnyElement>,
376 absolute_offset: Point<Pixels>,
377 prepaint_range: Range<PrepaintStateIndex>,
378 paint_range: Range<PaintIndex>,
379}
380
381pub(crate) struct Frame {
382 pub(crate) focus: Option<FocusId>,
383 pub(crate) window_active: bool,
384 pub(crate) element_states: FxHashMap<(GlobalElementId, TypeId), ElementStateBox>,
385 accessed_element_states: Vec<(GlobalElementId, TypeId)>,
386 pub(crate) mouse_listeners: Vec<Option<AnyMouseListener>>,
387 pub(crate) dispatch_tree: DispatchTree,
388 pub(crate) scene: Scene,
389 pub(crate) hitboxes: Vec<Hitbox>,
390 pub(crate) deferred_draws: Vec<DeferredDraw>,
391 pub(crate) input_handlers: Vec<Option<PlatformInputHandler>>,
392 pub(crate) tooltip_requests: Vec<Option<TooltipRequest>>,
393 pub(crate) cursor_styles: Vec<CursorStyleRequest>,
394 #[cfg(any(test, feature = "test-support"))]
395 pub(crate) debug_bounds: FxHashMap<String, Bounds<Pixels>>,
396}
397
398#[derive(Clone, Default)]
399pub(crate) struct PrepaintStateIndex {
400 hitboxes_index: usize,
401 tooltips_index: usize,
402 deferred_draws_index: usize,
403 dispatch_tree_index: usize,
404 accessed_element_states_index: usize,
405 line_layout_index: LineLayoutIndex,
406}
407
408#[derive(Clone, Default)]
409pub(crate) struct PaintIndex {
410 scene_index: usize,
411 mouse_listeners_index: usize,
412 input_handlers_index: usize,
413 cursor_styles_index: usize,
414 accessed_element_states_index: usize,
415 line_layout_index: LineLayoutIndex,
416}
417
418impl Frame {
419 pub(crate) fn new(dispatch_tree: DispatchTree) -> Self {
420 Frame {
421 focus: None,
422 window_active: false,
423 element_states: FxHashMap::default(),
424 accessed_element_states: Vec::new(),
425 mouse_listeners: Vec::new(),
426 dispatch_tree,
427 scene: Scene::default(),
428 hitboxes: Vec::new(),
429 deferred_draws: Vec::new(),
430 input_handlers: Vec::new(),
431 tooltip_requests: Vec::new(),
432 cursor_styles: Vec::new(),
433
434 #[cfg(any(test, feature = "test-support"))]
435 debug_bounds: FxHashMap::default(),
436 }
437 }
438
439 pub(crate) fn clear(&mut self) {
440 self.element_states.clear();
441 self.accessed_element_states.clear();
442 self.mouse_listeners.clear();
443 self.dispatch_tree.clear();
444 self.scene.clear();
445 self.input_handlers.clear();
446 self.tooltip_requests.clear();
447 self.cursor_styles.clear();
448 self.hitboxes.clear();
449 self.deferred_draws.clear();
450 }
451
452 pub(crate) fn hit_test(&self, position: Point<Pixels>) -> HitTest {
453 let mut hit_test = HitTest::default();
454 for hitbox in self.hitboxes.iter().rev() {
455 let bounds = hitbox.bounds.intersect(&hitbox.content_mask.bounds);
456 if bounds.contains(&position) {
457 hit_test.0.push(hitbox.id);
458 if hitbox.opaque {
459 break;
460 }
461 }
462 }
463 hit_test
464 }
465
466 pub(crate) fn focus_path(&self) -> SmallVec<[FocusId; 8]> {
467 self.focus
468 .map(|focus_id| self.dispatch_tree.focus_path(focus_id))
469 .unwrap_or_default()
470 }
471
472 pub(crate) fn finish(&mut self, prev_frame: &mut Self) {
473 for element_state_key in &self.accessed_element_states {
474 if let Some((element_state_key, element_state)) =
475 prev_frame.element_states.remove_entry(element_state_key)
476 {
477 self.element_states.insert(element_state_key, element_state);
478 }
479 }
480
481 self.scene.finish();
482 }
483}
484
485// Holds the state for a specific window.
486#[doc(hidden)]
487pub struct Window {
488 pub(crate) handle: AnyWindowHandle,
489 pub(crate) removed: bool,
490 pub(crate) platform_window: Box<dyn PlatformWindow>,
491 display_id: Option<DisplayId>,
492 sprite_atlas: Arc<dyn PlatformAtlas>,
493 text_system: Arc<WindowTextSystem>,
494 rem_size: Pixels,
495 /// The stack of override values for the window's rem size.
496 ///
497 /// This is used by `with_rem_size` to allow rendering an element tree with
498 /// a given rem size.
499 rem_size_override_stack: SmallVec<[Pixels; 8]>,
500 pub(crate) viewport_size: Size<Pixels>,
501 layout_engine: Option<TaffyLayoutEngine>,
502 pub(crate) root_view: Option<AnyView>,
503 pub(crate) element_id_stack: SmallVec<[ElementId; 32]>,
504 pub(crate) text_style_stack: Vec<TextStyleRefinement>,
505 pub(crate) element_offset_stack: Vec<Point<Pixels>>,
506 pub(crate) content_mask_stack: Vec<ContentMask<Pixels>>,
507 pub(crate) requested_autoscroll: Option<Bounds<Pixels>>,
508 pub(crate) rendered_frame: Frame,
509 pub(crate) next_frame: Frame,
510 pub(crate) next_hitbox_id: HitboxId,
511 pub(crate) next_tooltip_id: TooltipId,
512 pub(crate) tooltip_bounds: Option<TooltipBounds>,
513 next_frame_callbacks: Rc<RefCell<Vec<FrameCallback>>>,
514 pub(crate) dirty_views: FxHashSet<EntityId>,
515 pub(crate) focus_handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
516 focus_listeners: SubscriberSet<(), AnyWindowFocusListener>,
517 focus_lost_listeners: SubscriberSet<(), AnyObserver>,
518 default_prevented: bool,
519 mouse_position: Point<Pixels>,
520 mouse_hit_test: HitTest,
521 modifiers: Modifiers,
522 scale_factor: f32,
523 bounds_observers: SubscriberSet<(), AnyObserver>,
524 appearance: WindowAppearance,
525 appearance_observers: SubscriberSet<(), AnyObserver>,
526 active: Rc<Cell<bool>>,
527 pub(crate) dirty: Rc<Cell<bool>>,
528 pub(crate) needs_present: Rc<Cell<bool>>,
529 pub(crate) last_input_timestamp: Rc<Cell<Instant>>,
530 pub(crate) refreshing: bool,
531 pub(crate) draw_phase: DrawPhase,
532 activation_observers: SubscriberSet<(), AnyObserver>,
533 pub(crate) focus: Option<FocusId>,
534 focus_enabled: bool,
535 pending_input: Option<PendingInput>,
536 prompt: Option<RenderablePromptHandle>,
537}
538
539#[derive(Clone, Copy, Debug, Eq, PartialEq)]
540pub(crate) enum DrawPhase {
541 None,
542 Prepaint,
543 Paint,
544 Focus,
545}
546
547#[derive(Default, Debug)]
548struct PendingInput {
549 keystrokes: SmallVec<[Keystroke; 1]>,
550 bindings: SmallVec<[KeyBinding; 1]>,
551 focus: Option<FocusId>,
552 timer: Option<Task<()>>,
553}
554
555impl PendingInput {
556 fn input(&self) -> String {
557 self.keystrokes
558 .iter()
559 .flat_map(|k| k.ime_key.clone())
560 .collect::<Vec<String>>()
561 .join("")
562 }
563
564 fn used_by_binding(&self, binding: &KeyBinding) -> bool {
565 if self.keystrokes.is_empty() {
566 return true;
567 }
568 let keystroke = &self.keystrokes[0];
569 for candidate in keystroke.match_candidates() {
570 if binding.match_keystrokes(&[candidate]) == KeyMatch::Pending {
571 return true;
572 }
573 }
574 false
575 }
576}
577
578pub(crate) struct ElementStateBox {
579 pub(crate) inner: Box<dyn Any>,
580 #[cfg(debug_assertions)]
581 pub(crate) type_name: &'static str,
582}
583
584fn default_bounds(display_id: Option<DisplayId>, cx: &mut AppContext) -> Bounds<DevicePixels> {
585 const DEFAULT_WINDOW_OFFSET: Point<DevicePixels> = point(DevicePixels(0), DevicePixels(35));
586
587 cx.active_window()
588 .and_then(|w| w.update(cx, |_, cx| cx.bounds()).ok())
589 .map(|bounds| bounds.map_origin(|origin| origin + DEFAULT_WINDOW_OFFSET))
590 .unwrap_or_else(|| {
591 let display = display_id
592 .map(|id| cx.find_display(id))
593 .unwrap_or_else(|| cx.primary_display());
594
595 display
596 .map(|display| display.default_bounds())
597 .unwrap_or_else(|| {
598 Bounds::new(point(DevicePixels(0), DevicePixels(0)), DEFAULT_WINDOW_SIZE)
599 })
600 })
601}
602
603impl Window {
604 pub(crate) fn new(
605 handle: AnyWindowHandle,
606 options: WindowOptions,
607 cx: &mut AppContext,
608 ) -> Result<Self> {
609 let WindowOptions {
610 window_bounds,
611 titlebar,
612 focus,
613 show,
614 kind,
615 is_movable,
616 display_id,
617 window_background,
618 app_id,
619 } = options;
620
621 let bounds = window_bounds
622 .map(|bounds| bounds.get_bounds())
623 .unwrap_or_else(|| default_bounds(display_id, cx));
624 let mut platform_window = cx.platform.open_window(
625 handle,
626 WindowParams {
627 bounds,
628 titlebar,
629 kind,
630 is_movable,
631 focus,
632 show,
633 display_id,
634 window_background,
635 },
636 )?;
637 let display_id = platform_window.display().map(|display| display.id());
638 let sprite_atlas = platform_window.sprite_atlas();
639 let mouse_position = platform_window.mouse_position();
640 let modifiers = platform_window.modifiers();
641 let content_size = platform_window.content_size();
642 let scale_factor = platform_window.scale_factor();
643 let appearance = platform_window.appearance();
644 let text_system = Arc::new(WindowTextSystem::new(cx.text_system().clone()));
645 let dirty = Rc::new(Cell::new(true));
646 let active = Rc::new(Cell::new(platform_window.is_active()));
647 let needs_present = Rc::new(Cell::new(false));
648 let next_frame_callbacks: Rc<RefCell<Vec<FrameCallback>>> = Default::default();
649 let last_input_timestamp = Rc::new(Cell::new(Instant::now()));
650
651 if let Some(ref window_open_state) = window_bounds {
652 match window_open_state {
653 WindowBounds::Fullscreen(_) => platform_window.toggle_fullscreen(),
654 WindowBounds::Maximized(_) => platform_window.zoom(),
655 WindowBounds::Windowed(_) => {}
656 }
657 }
658
659 platform_window.on_close(Box::new({
660 let mut cx = cx.to_async();
661 move || {
662 let _ = handle.update(&mut cx, |_, cx| cx.remove_window());
663 }
664 }));
665 platform_window.on_request_frame(Box::new({
666 let mut cx = cx.to_async();
667 let dirty = dirty.clone();
668 let active = active.clone();
669 let needs_present = needs_present.clone();
670 let next_frame_callbacks = next_frame_callbacks.clone();
671 let last_input_timestamp = last_input_timestamp.clone();
672 move || {
673 let next_frame_callbacks = next_frame_callbacks.take();
674 if !next_frame_callbacks.is_empty() {
675 handle
676 .update(&mut cx, |_, cx| {
677 for callback in next_frame_callbacks {
678 callback(cx);
679 }
680 })
681 .log_err();
682 }
683
684 // Keep presenting the current scene for 1 extra second since the
685 // last input to prevent the display from underclocking the refresh rate.
686 let needs_present = needs_present.get()
687 || (active.get()
688 && last_input_timestamp.get().elapsed() < Duration::from_secs(1));
689
690 if dirty.get() {
691 measure("frame duration", || {
692 handle
693 .update(&mut cx, |_, cx| {
694 cx.draw();
695 cx.present();
696 })
697 .log_err();
698 })
699 } else if needs_present {
700 handle.update(&mut cx, |_, cx| cx.present()).log_err();
701 }
702
703 handle
704 .update(&mut cx, |_, cx| {
705 cx.complete_frame();
706 })
707 .log_err();
708 }
709 }));
710 platform_window.on_resize(Box::new({
711 let mut cx = cx.to_async();
712 move |_, _| {
713 handle
714 .update(&mut cx, |_, cx| cx.bounds_changed())
715 .log_err();
716 }
717 }));
718 platform_window.on_moved(Box::new({
719 let mut cx = cx.to_async();
720 move || {
721 handle
722 .update(&mut cx, |_, cx| cx.bounds_changed())
723 .log_err();
724 }
725 }));
726 platform_window.on_appearance_changed(Box::new({
727 let mut cx = cx.to_async();
728 move || {
729 handle
730 .update(&mut cx, |_, cx| cx.appearance_changed())
731 .log_err();
732 }
733 }));
734 platform_window.on_active_status_change(Box::new({
735 let mut cx = cx.to_async();
736 move |active| {
737 handle
738 .update(&mut cx, |_, cx| {
739 cx.window.active.set(active);
740 cx.window
741 .activation_observers
742 .clone()
743 .retain(&(), |callback| callback(cx));
744 cx.refresh();
745 })
746 .log_err();
747 }
748 }));
749
750 platform_window.on_input({
751 let mut cx = cx.to_async();
752 Box::new(move |event| {
753 handle
754 .update(&mut cx, |_, cx| cx.dispatch_event(event))
755 .log_err()
756 .unwrap_or(DispatchEventResult::default())
757 })
758 });
759
760 if let Some(app_id) = app_id {
761 platform_window.set_app_id(&app_id);
762 }
763
764 Ok(Window {
765 handle,
766 removed: false,
767 platform_window,
768 display_id,
769 sprite_atlas,
770 text_system,
771 rem_size: px(16.),
772 rem_size_override_stack: SmallVec::new(),
773 viewport_size: content_size,
774 layout_engine: Some(TaffyLayoutEngine::new()),
775 root_view: None,
776 element_id_stack: SmallVec::default(),
777 text_style_stack: Vec::new(),
778 element_offset_stack: Vec::new(),
779 content_mask_stack: Vec::new(),
780 requested_autoscroll: None,
781 rendered_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
782 next_frame: Frame::new(DispatchTree::new(cx.keymap.clone(), cx.actions.clone())),
783 next_frame_callbacks,
784 next_hitbox_id: HitboxId::default(),
785 next_tooltip_id: TooltipId::default(),
786 tooltip_bounds: None,
787 dirty_views: FxHashSet::default(),
788 focus_handles: Arc::new(RwLock::new(SlotMap::with_key())),
789 focus_listeners: SubscriberSet::new(),
790 focus_lost_listeners: SubscriberSet::new(),
791 default_prevented: true,
792 mouse_position,
793 mouse_hit_test: HitTest::default(),
794 modifiers,
795 scale_factor,
796 bounds_observers: SubscriberSet::new(),
797 appearance,
798 appearance_observers: SubscriberSet::new(),
799 active,
800 dirty,
801 needs_present,
802 last_input_timestamp,
803 refreshing: false,
804 draw_phase: DrawPhase::None,
805 activation_observers: SubscriberSet::new(),
806 focus: None,
807 focus_enabled: true,
808 pending_input: None,
809 prompt: None,
810 })
811 }
812 fn new_focus_listener(
813 &mut self,
814 value: AnyWindowFocusListener,
815 ) -> (Subscription, impl FnOnce()) {
816 self.focus_listeners.insert((), value)
817 }
818}
819
820#[derive(Clone, Debug, Default, PartialEq, Eq)]
821pub(crate) struct DispatchEventResult {
822 pub propagate: bool,
823 pub default_prevented: bool,
824}
825
826/// Indicates which region of the window is visible. Content falling outside of this mask will not be
827/// rendered. Currently, only rectangular content masks are supported, but we give the mask its own type
828/// to leave room to support more complex shapes in the future.
829#[derive(Clone, Debug, Default, PartialEq, Eq)]
830#[repr(C)]
831pub struct ContentMask<P: Clone + Default + Debug> {
832 /// The bounds
833 pub bounds: Bounds<P>,
834}
835
836impl ContentMask<Pixels> {
837 /// Scale the content mask's pixel units by the given scaling factor.
838 pub fn scale(&self, factor: f32) -> ContentMask<ScaledPixels> {
839 ContentMask {
840 bounds: self.bounds.scale(factor),
841 }
842 }
843
844 /// Intersect the content mask with the given content mask.
845 pub fn intersect(&self, other: &Self) -> Self {
846 let bounds = self.bounds.intersect(&other.bounds);
847 ContentMask { bounds }
848 }
849}
850
851/// Provides access to application state in the context of a single window. Derefs
852/// to an [`AppContext`], so you can also pass a [`WindowContext`] to any method that takes
853/// an [`AppContext`] and call any [`AppContext`] methods.
854pub struct WindowContext<'a> {
855 pub(crate) app: &'a mut AppContext,
856 pub(crate) window: &'a mut Window,
857}
858
859impl<'a> WindowContext<'a> {
860 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window) -> Self {
861 Self { app, window }
862 }
863
864 /// Obtain a handle to the window that belongs to this context.
865 pub fn window_handle(&self) -> AnyWindowHandle {
866 self.window.handle
867 }
868
869 /// Mark the window as dirty, scheduling it to be redrawn on the next frame.
870 pub fn refresh(&mut self) {
871 if self.window.draw_phase == DrawPhase::None {
872 self.window.refreshing = true;
873 self.window.dirty.set(true);
874 }
875 }
876
877 /// Indicate that this view has changed, which will invoke any observers and also mark the window as dirty.
878 /// If this view or any of its ancestors are *cached*, notifying it will cause it or its ancestors to be redrawn.
879 pub fn notify(&mut self, view_id: EntityId) {
880 for view_id in self
881 .window
882 .rendered_frame
883 .dispatch_tree
884 .view_path(view_id)
885 .into_iter()
886 .rev()
887 {
888 if !self.window.dirty_views.insert(view_id) {
889 break;
890 }
891 }
892
893 if self.window.draw_phase == DrawPhase::None {
894 self.window.dirty.set(true);
895 self.app.push_effect(Effect::Notify { emitter: view_id });
896 }
897 }
898
899 /// Close this window.
900 pub fn remove_window(&mut self) {
901 self.window.removed = true;
902 }
903
904 /// Obtain a new [`FocusHandle`], which allows you to track and manipulate the keyboard focus
905 /// for elements rendered within this window.
906 pub fn focus_handle(&mut self) -> FocusHandle {
907 FocusHandle::new(&self.window.focus_handles)
908 }
909
910 /// Obtain the currently focused [`FocusHandle`]. If no elements are focused, returns `None`.
911 pub fn focused(&self) -> Option<FocusHandle> {
912 self.window
913 .focus
914 .and_then(|id| FocusHandle::for_id(id, &self.window.focus_handles))
915 }
916
917 /// Move focus to the element associated with the given [`FocusHandle`].
918 pub fn focus(&mut self, handle: &FocusHandle) {
919 if !self.window.focus_enabled || self.window.focus == Some(handle.id) {
920 return;
921 }
922
923 self.window.focus = Some(handle.id);
924 self.window
925 .rendered_frame
926 .dispatch_tree
927 .clear_pending_keystrokes();
928 self.refresh();
929 }
930
931 /// Remove focus from all elements within this context's window.
932 pub fn blur(&mut self) {
933 if !self.window.focus_enabled {
934 return;
935 }
936
937 self.window.focus = None;
938 self.refresh();
939 }
940
941 /// Blur the window and don't allow anything in it to be focused again.
942 pub fn disable_focus(&mut self) {
943 self.blur();
944 self.window.focus_enabled = false;
945 }
946
947 /// Accessor for the text system.
948 pub fn text_system(&self) -> &Arc<WindowTextSystem> {
949 &self.window.text_system
950 }
951
952 /// The current text style. Which is composed of all the style refinements provided to `with_text_style`.
953 pub fn text_style(&self) -> TextStyle {
954 let mut style = TextStyle::default();
955 for refinement in &self.window.text_style_stack {
956 style.refine(refinement);
957 }
958 style
959 }
960
961 /// Check if the platform window is maximized
962 /// On some platforms (namely Windows) this is different than the bounds being the size of the display
963 pub fn is_maximized(&self) -> bool {
964 self.window.platform_window.is_maximized()
965 }
966
967 /// Return the `WindowBounds` to indicate that how a window should be opened
968 /// after it has been closed
969 pub fn window_bounds(&self) -> WindowBounds {
970 self.window.platform_window.window_bounds()
971 }
972
973 /// Dispatch the given action on the currently focused element.
974 pub fn dispatch_action(&mut self, action: Box<dyn Action>) {
975 let focus_handle = self.focused();
976
977 let window = self.window.handle;
978 self.app.defer(move |cx| {
979 window
980 .update(cx, |_, cx| {
981 let node_id = focus_handle
982 .and_then(|handle| {
983 cx.window
984 .rendered_frame
985 .dispatch_tree
986 .focusable_node_id(handle.id)
987 })
988 .unwrap_or_else(|| cx.window.rendered_frame.dispatch_tree.root_node_id());
989
990 cx.dispatch_action_on_node(node_id, action.as_ref());
991 })
992 .log_err();
993 })
994 }
995
996 pub(crate) fn dispatch_keystroke_observers(
997 &mut self,
998 event: &dyn Any,
999 action: Option<Box<dyn Action>>,
1000 ) {
1001 let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() else {
1002 return;
1003 };
1004
1005 self.keystroke_observers
1006 .clone()
1007 .retain(&(), move |callback| {
1008 (callback)(
1009 &KeystrokeEvent {
1010 keystroke: key_down_event.keystroke.clone(),
1011 action: action.as_ref().map(|action| action.boxed_clone()),
1012 },
1013 self,
1014 );
1015 true
1016 });
1017 }
1018
1019 pub(crate) fn clear_pending_keystrokes(&mut self) {
1020 self.window
1021 .rendered_frame
1022 .dispatch_tree
1023 .clear_pending_keystrokes();
1024 self.window
1025 .next_frame
1026 .dispatch_tree
1027 .clear_pending_keystrokes();
1028 }
1029
1030 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
1031 /// that are currently on the stack to be returned to the app.
1032 pub fn defer(&mut self, f: impl FnOnce(&mut WindowContext) + 'static) {
1033 let handle = self.window.handle;
1034 self.app.defer(move |cx| {
1035 handle.update(cx, |_, cx| f(cx)).ok();
1036 });
1037 }
1038
1039 /// Subscribe to events emitted by a model or view.
1040 /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
1041 /// The callback will be invoked a handle to the emitting entity (either a [`View`] or [`Model`]), the event, and a window context for the current window.
1042 pub fn observe<E, T>(
1043 &mut self,
1044 entity: &E,
1045 mut on_notify: impl FnMut(E, &mut WindowContext<'_>) + 'static,
1046 ) -> Subscription
1047 where
1048 E: Entity<T>,
1049 {
1050 let entity_id = entity.entity_id();
1051 let entity = entity.downgrade();
1052 let window_handle = self.window.handle;
1053 self.app.new_observer(
1054 entity_id,
1055 Box::new(move |cx| {
1056 window_handle
1057 .update(cx, |_, cx| {
1058 if let Some(handle) = E::upgrade_from(&entity) {
1059 on_notify(handle, cx);
1060 true
1061 } else {
1062 false
1063 }
1064 })
1065 .unwrap_or(false)
1066 }),
1067 )
1068 }
1069
1070 /// Subscribe to events emitted by a model or view.
1071 /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
1072 /// 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.
1073 pub fn subscribe<Emitter, E, Evt>(
1074 &mut self,
1075 entity: &E,
1076 mut on_event: impl FnMut(E, &Evt, &mut WindowContext<'_>) + 'static,
1077 ) -> Subscription
1078 where
1079 Emitter: EventEmitter<Evt>,
1080 E: Entity<Emitter>,
1081 Evt: 'static,
1082 {
1083 let entity_id = entity.entity_id();
1084 let entity = entity.downgrade();
1085 let window_handle = self.window.handle;
1086 self.app.new_subscription(
1087 entity_id,
1088 (
1089 TypeId::of::<Evt>(),
1090 Box::new(move |event, cx| {
1091 window_handle
1092 .update(cx, |_, cx| {
1093 if let Some(handle) = E::upgrade_from(&entity) {
1094 let event = event.downcast_ref().expect("invalid event type");
1095 on_event(handle, event, cx);
1096 true
1097 } else {
1098 false
1099 }
1100 })
1101 .unwrap_or(false)
1102 }),
1103 ),
1104 )
1105 }
1106
1107 /// Creates an [`AsyncWindowContext`], which has a static lifetime and can be held across
1108 /// await points in async code.
1109 pub fn to_async(&self) -> AsyncWindowContext {
1110 AsyncWindowContext::new(self.app.to_async(), self.window.handle)
1111 }
1112
1113 /// Schedule the given closure to be run directly after the current frame is rendered.
1114 pub fn on_next_frame(&mut self, callback: impl FnOnce(&mut WindowContext) + 'static) {
1115 RefCell::borrow_mut(&self.window.next_frame_callbacks).push(Box::new(callback));
1116 }
1117
1118 /// Spawn the future returned by the given closure on the application thread pool.
1119 /// The closure is provided a handle to the current window and an `AsyncWindowContext` for
1120 /// use within your future.
1121 pub fn spawn<Fut, R>(&mut self, f: impl FnOnce(AsyncWindowContext) -> Fut) -> Task<R>
1122 where
1123 R: 'static,
1124 Fut: Future<Output = R> + 'static,
1125 {
1126 self.app
1127 .spawn(|app| f(AsyncWindowContext::new(app, self.window.handle)))
1128 }
1129
1130 fn bounds_changed(&mut self) {
1131 self.window.scale_factor = self.window.platform_window.scale_factor();
1132 self.window.viewport_size = self.window.platform_window.content_size();
1133 self.window.display_id = self
1134 .window
1135 .platform_window
1136 .display()
1137 .map(|display| display.id());
1138
1139 self.refresh();
1140
1141 self.window
1142 .bounds_observers
1143 .clone()
1144 .retain(&(), |callback| callback(self));
1145 }
1146
1147 /// Returns the bounds of the current window in the global coordinate space, which could span across multiple displays.
1148 pub fn bounds(&self) -> Bounds<DevicePixels> {
1149 self.window.platform_window.bounds()
1150 }
1151
1152 /// Returns whether or not the window is currently fullscreen
1153 pub fn is_fullscreen(&self) -> bool {
1154 self.window.platform_window.is_fullscreen()
1155 }
1156
1157 fn appearance_changed(&mut self) {
1158 self.window.appearance = self.window.platform_window.appearance();
1159
1160 self.window
1161 .appearance_observers
1162 .clone()
1163 .retain(&(), |callback| callback(self));
1164 }
1165
1166 /// Returns the appearance of the current window.
1167 pub fn appearance(&self) -> WindowAppearance {
1168 self.window.appearance
1169 }
1170
1171 /// Returns the size of the drawable area within the window.
1172 pub fn viewport_size(&self) -> Size<Pixels> {
1173 self.window.viewport_size
1174 }
1175
1176 /// Returns whether this window is focused by the operating system (receiving key events).
1177 pub fn is_window_active(&self) -> bool {
1178 self.window.active.get()
1179 }
1180
1181 /// Toggle zoom on the window.
1182 pub fn zoom_window(&self) {
1183 self.window.platform_window.zoom();
1184 }
1185
1186 /// Opens the native title bar context menu, useful when implementing client side decorations (Wayland and X11)
1187 pub fn show_window_menu(&self, position: Point<Pixels>) {
1188 self.window.platform_window.show_window_menu(position)
1189 }
1190
1191 /// Tells the compositor to take control of window movement (Wayland and X11)
1192 ///
1193 /// Events may not be received during a move operation.
1194 pub fn start_system_move(&self) {
1195 self.window.platform_window.start_system_move()
1196 }
1197
1198 /// Returns whether the title bar window controls need to be rendered by the application (Wayland and X11)
1199 pub fn should_render_window_controls(&self) -> bool {
1200 self.window.platform_window.should_render_window_controls()
1201 }
1202
1203 /// Updates the window's title at the platform level.
1204 pub fn set_window_title(&mut self, title: &str) {
1205 self.window.platform_window.set_title(title);
1206 }
1207
1208 /// Sets the application identifier.
1209 pub fn set_app_id(&mut self, app_id: &str) {
1210 self.window.platform_window.set_app_id(app_id);
1211 }
1212
1213 /// Sets the window background appearance.
1214 pub fn set_background_appearance(&mut self, background_appearance: WindowBackgroundAppearance) {
1215 self.window
1216 .platform_window
1217 .set_background_appearance(background_appearance);
1218 }
1219
1220 /// Mark the window as dirty at the platform level.
1221 pub fn set_window_edited(&mut self, edited: bool) {
1222 self.window.platform_window.set_edited(edited);
1223 }
1224
1225 /// Determine the display on which the window is visible.
1226 pub fn display(&self) -> Option<Rc<dyn PlatformDisplay>> {
1227 self.platform
1228 .displays()
1229 .into_iter()
1230 .find(|display| Some(display.id()) == self.window.display_id)
1231 }
1232
1233 /// Show the platform character palette.
1234 pub fn show_character_palette(&self) {
1235 self.window.platform_window.show_character_palette();
1236 }
1237
1238 /// The scale factor of the display associated with the window. For example, it could
1239 /// return 2.0 for a "retina" display, indicating that each logical pixel should actually
1240 /// be rendered as two pixels on screen.
1241 pub fn scale_factor(&self) -> f32 {
1242 self.window.scale_factor
1243 }
1244
1245 /// The size of an em for the base font of the application. Adjusting this value allows the
1246 /// UI to scale, just like zooming a web page.
1247 pub fn rem_size(&self) -> Pixels {
1248 self.window
1249 .rem_size_override_stack
1250 .last()
1251 .copied()
1252 .unwrap_or(self.window.rem_size)
1253 }
1254
1255 /// Sets the size of an em for the base font of the application. Adjusting this value allows the
1256 /// UI to scale, just like zooming a web page.
1257 pub fn set_rem_size(&mut self, rem_size: impl Into<Pixels>) {
1258 self.window.rem_size = rem_size.into();
1259 }
1260
1261 /// Executes the provided function with the specified rem size.
1262 ///
1263 /// This method must only be called as part of element drawing.
1264 pub fn with_rem_size<F, R>(&mut self, rem_size: Option<impl Into<Pixels>>, f: F) -> R
1265 where
1266 F: FnOnce(&mut Self) -> R,
1267 {
1268 debug_assert!(
1269 matches!(
1270 self.window.draw_phase,
1271 DrawPhase::Prepaint | DrawPhase::Paint
1272 ),
1273 "this method can only be called during request_layout, prepaint, or paint"
1274 );
1275
1276 if let Some(rem_size) = rem_size {
1277 self.window.rem_size_override_stack.push(rem_size.into());
1278 let result = f(self);
1279 self.window.rem_size_override_stack.pop();
1280 result
1281 } else {
1282 f(self)
1283 }
1284 }
1285
1286 /// The line height associated with the current text style.
1287 pub fn line_height(&self) -> Pixels {
1288 let rem_size = self.rem_size();
1289 let text_style = self.text_style();
1290 text_style
1291 .line_height
1292 .to_pixels(text_style.font_size, rem_size)
1293 }
1294
1295 /// Call to prevent the default action of an event. Currently only used to prevent
1296 /// parent elements from becoming focused on mouse down.
1297 pub fn prevent_default(&mut self) {
1298 self.window.default_prevented = true;
1299 }
1300
1301 /// Obtain whether default has been prevented for the event currently being dispatched.
1302 pub fn default_prevented(&self) -> bool {
1303 self.window.default_prevented
1304 }
1305
1306 /// Determine whether the given action is available along the dispatch path to the currently focused element.
1307 pub fn is_action_available(&self, action: &dyn Action) -> bool {
1308 let target = self
1309 .focused()
1310 .and_then(|focused_handle| {
1311 self.window
1312 .rendered_frame
1313 .dispatch_tree
1314 .focusable_node_id(focused_handle.id)
1315 })
1316 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
1317 self.window
1318 .rendered_frame
1319 .dispatch_tree
1320 .is_action_available(action, target)
1321 }
1322
1323 /// The position of the mouse relative to the window.
1324 pub fn mouse_position(&self) -> Point<Pixels> {
1325 self.window.mouse_position
1326 }
1327
1328 /// The current state of the keyboard's modifiers
1329 pub fn modifiers(&self) -> Modifiers {
1330 self.window.modifiers
1331 }
1332
1333 fn complete_frame(&self) {
1334 self.window.platform_window.completed_frame();
1335 }
1336
1337 /// Produces a new frame and assigns it to `rendered_frame`. To actually show
1338 /// the contents of the new [Scene], use [present].
1339 #[profiling::function]
1340 pub fn draw(&mut self) {
1341 self.window.dirty.set(false);
1342 self.window.requested_autoscroll = None;
1343
1344 // Restore the previously-used input handler.
1345 if let Some(input_handler) = self.window.platform_window.take_input_handler() {
1346 self.window
1347 .rendered_frame
1348 .input_handlers
1349 .push(Some(input_handler));
1350 }
1351
1352 self.draw_roots();
1353 self.window.dirty_views.clear();
1354
1355 self.window
1356 .next_frame
1357 .dispatch_tree
1358 .preserve_pending_keystrokes(
1359 &mut self.window.rendered_frame.dispatch_tree,
1360 self.window.focus,
1361 );
1362 self.window.next_frame.focus = self.window.focus;
1363 self.window.next_frame.window_active = self.window.active.get();
1364
1365 // Register requested input handler with the platform window.
1366 if let Some(input_handler) = self.window.next_frame.input_handlers.pop() {
1367 self.window
1368 .platform_window
1369 .set_input_handler(input_handler.unwrap());
1370 }
1371
1372 self.window.layout_engine.as_mut().unwrap().clear();
1373 self.text_system().finish_frame();
1374 self.window
1375 .next_frame
1376 .finish(&mut self.window.rendered_frame);
1377 ELEMENT_ARENA.with_borrow_mut(|element_arena| {
1378 let percentage = (element_arena.len() as f32 / element_arena.capacity() as f32) * 100.;
1379 if percentage >= 80. {
1380 log::warn!("elevated element arena occupation: {}.", percentage);
1381 }
1382 element_arena.clear();
1383 });
1384
1385 self.window.draw_phase = DrawPhase::Focus;
1386 let previous_focus_path = self.window.rendered_frame.focus_path();
1387 let previous_window_active = self.window.rendered_frame.window_active;
1388 mem::swap(&mut self.window.rendered_frame, &mut self.window.next_frame);
1389 self.window.next_frame.clear();
1390 let current_focus_path = self.window.rendered_frame.focus_path();
1391 let current_window_active = self.window.rendered_frame.window_active;
1392
1393 if previous_focus_path != current_focus_path
1394 || previous_window_active != current_window_active
1395 {
1396 if !previous_focus_path.is_empty() && current_focus_path.is_empty() {
1397 self.window
1398 .focus_lost_listeners
1399 .clone()
1400 .retain(&(), |listener| listener(self));
1401 }
1402
1403 let event = FocusEvent {
1404 previous_focus_path: if previous_window_active {
1405 previous_focus_path
1406 } else {
1407 Default::default()
1408 },
1409 current_focus_path: if current_window_active {
1410 current_focus_path
1411 } else {
1412 Default::default()
1413 },
1414 };
1415 self.window
1416 .focus_listeners
1417 .clone()
1418 .retain(&(), |listener| listener(&event, self));
1419 }
1420
1421 self.reset_cursor_style();
1422 self.window.refreshing = false;
1423 self.window.draw_phase = DrawPhase::None;
1424 self.window.needs_present.set(true);
1425 }
1426
1427 #[profiling::function]
1428 fn present(&self) {
1429 self.window
1430 .platform_window
1431 .draw(&self.window.rendered_frame.scene);
1432 self.window.needs_present.set(false);
1433 profiling::finish_frame!();
1434 }
1435
1436 fn draw_roots(&mut self) {
1437 self.window.draw_phase = DrawPhase::Prepaint;
1438 self.window.tooltip_bounds.take();
1439
1440 // Layout all root elements.
1441 let mut root_element = self.window.root_view.as_ref().unwrap().clone().into_any();
1442 root_element.prepaint_as_root(Point::default(), self.window.viewport_size.into(), self);
1443
1444 let mut sorted_deferred_draws =
1445 (0..self.window.next_frame.deferred_draws.len()).collect::<SmallVec<[_; 8]>>();
1446 sorted_deferred_draws.sort_by_key(|ix| self.window.next_frame.deferred_draws[*ix].priority);
1447 self.prepaint_deferred_draws(&sorted_deferred_draws);
1448
1449 let mut prompt_element = None;
1450 let mut active_drag_element = None;
1451 let mut tooltip_element = None;
1452 if let Some(prompt) = self.window.prompt.take() {
1453 let mut element = prompt.view.any_view().into_any();
1454 element.prepaint_as_root(Point::default(), self.window.viewport_size.into(), self);
1455 prompt_element = Some(element);
1456 self.window.prompt = Some(prompt);
1457 } else if let Some(active_drag) = self.app.active_drag.take() {
1458 let mut element = active_drag.view.clone().into_any();
1459 let offset = self.mouse_position() - active_drag.cursor_offset;
1460 element.prepaint_as_root(offset, AvailableSpace::min_size(), self);
1461 active_drag_element = Some(element);
1462 self.app.active_drag = Some(active_drag);
1463 } else {
1464 tooltip_element = self.prepaint_tooltip();
1465 }
1466
1467 self.window.mouse_hit_test = self.window.next_frame.hit_test(self.window.mouse_position);
1468
1469 // Now actually paint the elements.
1470 self.window.draw_phase = DrawPhase::Paint;
1471 root_element.paint(self);
1472
1473 self.paint_deferred_draws(&sorted_deferred_draws);
1474
1475 if let Some(mut prompt_element) = prompt_element {
1476 prompt_element.paint(self)
1477 } else if let Some(mut drag_element) = active_drag_element {
1478 drag_element.paint(self);
1479 } else if let Some(mut tooltip_element) = tooltip_element {
1480 tooltip_element.paint(self);
1481 }
1482 }
1483
1484 fn prepaint_tooltip(&mut self) -> Option<AnyElement> {
1485 let tooltip_request = self.window.next_frame.tooltip_requests.last().cloned()?;
1486 let tooltip_request = tooltip_request.unwrap();
1487 let mut element = tooltip_request.tooltip.view.clone().into_any();
1488 let mouse_position = tooltip_request.tooltip.mouse_position;
1489 let tooltip_size = element.layout_as_root(AvailableSpace::min_size(), self);
1490
1491 let mut tooltip_bounds = Bounds::new(mouse_position + point(px(1.), px(1.)), tooltip_size);
1492 let window_bounds = Bounds {
1493 origin: Point::default(),
1494 size: self.viewport_size(),
1495 };
1496
1497 if tooltip_bounds.right() > window_bounds.right() {
1498 let new_x = mouse_position.x - tooltip_bounds.size.width - px(1.);
1499 if new_x >= Pixels::ZERO {
1500 tooltip_bounds.origin.x = new_x;
1501 } else {
1502 tooltip_bounds.origin.x = cmp::max(
1503 Pixels::ZERO,
1504 tooltip_bounds.origin.x - tooltip_bounds.right() - window_bounds.right(),
1505 );
1506 }
1507 }
1508
1509 if tooltip_bounds.bottom() > window_bounds.bottom() {
1510 let new_y = mouse_position.y - tooltip_bounds.size.height - px(1.);
1511 if new_y >= Pixels::ZERO {
1512 tooltip_bounds.origin.y = new_y;
1513 } else {
1514 tooltip_bounds.origin.y = cmp::max(
1515 Pixels::ZERO,
1516 tooltip_bounds.origin.y - tooltip_bounds.bottom() - window_bounds.bottom(),
1517 );
1518 }
1519 }
1520
1521 self.with_absolute_element_offset(tooltip_bounds.origin, |cx| element.prepaint(cx));
1522
1523 self.window.tooltip_bounds = Some(TooltipBounds {
1524 id: tooltip_request.id,
1525 bounds: tooltip_bounds,
1526 });
1527 Some(element)
1528 }
1529
1530 fn prepaint_deferred_draws(&mut self, deferred_draw_indices: &[usize]) {
1531 assert_eq!(self.window.element_id_stack.len(), 0);
1532
1533 let mut deferred_draws = mem::take(&mut self.window.next_frame.deferred_draws);
1534 for deferred_draw_ix in deferred_draw_indices {
1535 let deferred_draw = &mut deferred_draws[*deferred_draw_ix];
1536 self.window
1537 .element_id_stack
1538 .clone_from(&deferred_draw.element_id_stack);
1539 self.window
1540 .text_style_stack
1541 .clone_from(&deferred_draw.text_style_stack);
1542 self.window
1543 .next_frame
1544 .dispatch_tree
1545 .set_active_node(deferred_draw.parent_node);
1546
1547 let prepaint_start = self.prepaint_index();
1548 if let Some(element) = deferred_draw.element.as_mut() {
1549 self.with_absolute_element_offset(deferred_draw.absolute_offset, |cx| {
1550 element.prepaint(cx)
1551 });
1552 } else {
1553 self.reuse_prepaint(deferred_draw.prepaint_range.clone());
1554 }
1555 let prepaint_end = self.prepaint_index();
1556 deferred_draw.prepaint_range = prepaint_start..prepaint_end;
1557 }
1558 assert_eq!(
1559 self.window.next_frame.deferred_draws.len(),
1560 0,
1561 "cannot call defer_draw during deferred drawing"
1562 );
1563 self.window.next_frame.deferred_draws = deferred_draws;
1564 self.window.element_id_stack.clear();
1565 self.window.text_style_stack.clear();
1566 }
1567
1568 fn paint_deferred_draws(&mut self, deferred_draw_indices: &[usize]) {
1569 assert_eq!(self.window.element_id_stack.len(), 0);
1570
1571 let mut deferred_draws = mem::take(&mut self.window.next_frame.deferred_draws);
1572 for deferred_draw_ix in deferred_draw_indices {
1573 let mut deferred_draw = &mut deferred_draws[*deferred_draw_ix];
1574 self.window
1575 .element_id_stack
1576 .clone_from(&deferred_draw.element_id_stack);
1577 self.window
1578 .next_frame
1579 .dispatch_tree
1580 .set_active_node(deferred_draw.parent_node);
1581
1582 let paint_start = self.paint_index();
1583 if let Some(element) = deferred_draw.element.as_mut() {
1584 element.paint(self);
1585 } else {
1586 self.reuse_paint(deferred_draw.paint_range.clone());
1587 }
1588 let paint_end = self.paint_index();
1589 deferred_draw.paint_range = paint_start..paint_end;
1590 }
1591 self.window.next_frame.deferred_draws = deferred_draws;
1592 self.window.element_id_stack.clear();
1593 }
1594
1595 pub(crate) fn prepaint_index(&self) -> PrepaintStateIndex {
1596 PrepaintStateIndex {
1597 hitboxes_index: self.window.next_frame.hitboxes.len(),
1598 tooltips_index: self.window.next_frame.tooltip_requests.len(),
1599 deferred_draws_index: self.window.next_frame.deferred_draws.len(),
1600 dispatch_tree_index: self.window.next_frame.dispatch_tree.len(),
1601 accessed_element_states_index: self.window.next_frame.accessed_element_states.len(),
1602 line_layout_index: self.window.text_system.layout_index(),
1603 }
1604 }
1605
1606 pub(crate) fn reuse_prepaint(&mut self, range: Range<PrepaintStateIndex>) {
1607 let window = &mut self.window;
1608 window.next_frame.hitboxes.extend(
1609 window.rendered_frame.hitboxes[range.start.hitboxes_index..range.end.hitboxes_index]
1610 .iter()
1611 .cloned(),
1612 );
1613 window.next_frame.tooltip_requests.extend(
1614 window.rendered_frame.tooltip_requests
1615 [range.start.tooltips_index..range.end.tooltips_index]
1616 .iter_mut()
1617 .map(|request| request.take()),
1618 );
1619 window.next_frame.accessed_element_states.extend(
1620 window.rendered_frame.accessed_element_states[range.start.accessed_element_states_index
1621 ..range.end.accessed_element_states_index]
1622 .iter()
1623 .map(|(id, type_id)| (GlobalElementId(id.0.clone()), *type_id)),
1624 );
1625 window
1626 .text_system
1627 .reuse_layouts(range.start.line_layout_index..range.end.line_layout_index);
1628
1629 let reused_subtree = window.next_frame.dispatch_tree.reuse_subtree(
1630 range.start.dispatch_tree_index..range.end.dispatch_tree_index,
1631 &mut window.rendered_frame.dispatch_tree,
1632 );
1633 window.next_frame.deferred_draws.extend(
1634 window.rendered_frame.deferred_draws
1635 [range.start.deferred_draws_index..range.end.deferred_draws_index]
1636 .iter()
1637 .map(|deferred_draw| DeferredDraw {
1638 parent_node: reused_subtree.refresh_node_id(deferred_draw.parent_node),
1639 element_id_stack: deferred_draw.element_id_stack.clone(),
1640 text_style_stack: deferred_draw.text_style_stack.clone(),
1641 priority: deferred_draw.priority,
1642 element: None,
1643 absolute_offset: deferred_draw.absolute_offset,
1644 prepaint_range: deferred_draw.prepaint_range.clone(),
1645 paint_range: deferred_draw.paint_range.clone(),
1646 }),
1647 );
1648 }
1649
1650 pub(crate) fn paint_index(&self) -> PaintIndex {
1651 PaintIndex {
1652 scene_index: self.window.next_frame.scene.len(),
1653 mouse_listeners_index: self.window.next_frame.mouse_listeners.len(),
1654 input_handlers_index: self.window.next_frame.input_handlers.len(),
1655 cursor_styles_index: self.window.next_frame.cursor_styles.len(),
1656 accessed_element_states_index: self.window.next_frame.accessed_element_states.len(),
1657 line_layout_index: self.window.text_system.layout_index(),
1658 }
1659 }
1660
1661 pub(crate) fn reuse_paint(&mut self, range: Range<PaintIndex>) {
1662 let window = &mut self.window;
1663
1664 window.next_frame.cursor_styles.extend(
1665 window.rendered_frame.cursor_styles
1666 [range.start.cursor_styles_index..range.end.cursor_styles_index]
1667 .iter()
1668 .cloned(),
1669 );
1670 window.next_frame.input_handlers.extend(
1671 window.rendered_frame.input_handlers
1672 [range.start.input_handlers_index..range.end.input_handlers_index]
1673 .iter_mut()
1674 .map(|handler| handler.take()),
1675 );
1676 window.next_frame.mouse_listeners.extend(
1677 window.rendered_frame.mouse_listeners
1678 [range.start.mouse_listeners_index..range.end.mouse_listeners_index]
1679 .iter_mut()
1680 .map(|listener| listener.take()),
1681 );
1682 window.next_frame.accessed_element_states.extend(
1683 window.rendered_frame.accessed_element_states[range.start.accessed_element_states_index
1684 ..range.end.accessed_element_states_index]
1685 .iter()
1686 .map(|(id, type_id)| (GlobalElementId(id.0.clone()), *type_id)),
1687 );
1688 window
1689 .text_system
1690 .reuse_layouts(range.start.line_layout_index..range.end.line_layout_index);
1691 window.next_frame.scene.replay(
1692 range.start.scene_index..range.end.scene_index,
1693 &window.rendered_frame.scene,
1694 );
1695 }
1696
1697 /// Push a text style onto the stack, and call a function with that style active.
1698 /// Use [`AppContext::text_style`] to get the current, combined text style. This method
1699 /// should only be called as part of element drawing.
1700 pub fn with_text_style<F, R>(&mut self, style: Option<TextStyleRefinement>, f: F) -> R
1701 where
1702 F: FnOnce(&mut Self) -> R,
1703 {
1704 debug_assert!(
1705 matches!(
1706 self.window.draw_phase,
1707 DrawPhase::Prepaint | DrawPhase::Paint
1708 ),
1709 "this method can only be called during request_layout, prepaint, or paint"
1710 );
1711 if let Some(style) = style {
1712 self.window.text_style_stack.push(style);
1713 let result = f(self);
1714 self.window.text_style_stack.pop();
1715 result
1716 } else {
1717 f(self)
1718 }
1719 }
1720
1721 /// Updates the cursor style at the platform level. This method should only be called
1722 /// during the prepaint phase of element drawing.
1723 pub fn set_cursor_style(&mut self, style: CursorStyle, hitbox: &Hitbox) {
1724 debug_assert_eq!(
1725 self.window.draw_phase,
1726 DrawPhase::Paint,
1727 "this method can only be called during paint"
1728 );
1729 self.window
1730 .next_frame
1731 .cursor_styles
1732 .push(CursorStyleRequest {
1733 hitbox_id: hitbox.id,
1734 style,
1735 });
1736 }
1737
1738 /// Sets a tooltip to be rendered for the upcoming frame. This method should only be called
1739 /// during the paint phase of element drawing.
1740 pub fn set_tooltip(&mut self, tooltip: AnyTooltip) -> TooltipId {
1741 debug_assert_eq!(
1742 self.window.draw_phase,
1743 DrawPhase::Prepaint,
1744 "this method can only be called during prepaint"
1745 );
1746 let id = TooltipId(post_inc(&mut self.window.next_tooltip_id.0));
1747 self.window
1748 .next_frame
1749 .tooltip_requests
1750 .push(Some(TooltipRequest { id, tooltip }));
1751 id
1752 }
1753
1754 /// Invoke the given function with the given content mask after intersecting it
1755 /// with the current mask. This method should only be called during element drawing.
1756 pub fn with_content_mask<R>(
1757 &mut self,
1758 mask: Option<ContentMask<Pixels>>,
1759 f: impl FnOnce(&mut Self) -> R,
1760 ) -> R {
1761 debug_assert!(
1762 matches!(
1763 self.window.draw_phase,
1764 DrawPhase::Prepaint | DrawPhase::Paint
1765 ),
1766 "this method can only be called during request_layout, prepaint, or paint"
1767 );
1768 if let Some(mask) = mask {
1769 let mask = mask.intersect(&self.content_mask());
1770 self.window_mut().content_mask_stack.push(mask);
1771 let result = f(self);
1772 self.window_mut().content_mask_stack.pop();
1773 result
1774 } else {
1775 f(self)
1776 }
1777 }
1778
1779 /// Updates the global element offset relative to the current offset. This is used to implement
1780 /// scrolling. This method should only be called during the prepaint phase of element drawing.
1781 pub fn with_element_offset<R>(
1782 &mut self,
1783 offset: Point<Pixels>,
1784 f: impl FnOnce(&mut Self) -> R,
1785 ) -> R {
1786 debug_assert_eq!(
1787 self.window.draw_phase,
1788 DrawPhase::Prepaint,
1789 "this method can only be called during request_layout, or prepaint"
1790 );
1791
1792 if offset.is_zero() {
1793 return f(self);
1794 };
1795
1796 let abs_offset = self.element_offset() + offset;
1797 self.with_absolute_element_offset(abs_offset, f)
1798 }
1799
1800 /// Updates the global element offset based on the given offset. This is used to implement
1801 /// drag handles and other manual painting of elements. This method should only be called during
1802 /// the prepaint phase of element drawing.
1803 pub fn with_absolute_element_offset<R>(
1804 &mut self,
1805 offset: Point<Pixels>,
1806 f: impl FnOnce(&mut Self) -> R,
1807 ) -> R {
1808 debug_assert_eq!(
1809 self.window.draw_phase,
1810 DrawPhase::Prepaint,
1811 "this method can only be called during request_layout, or prepaint"
1812 );
1813 self.window_mut().element_offset_stack.push(offset);
1814 let result = f(self);
1815 self.window_mut().element_offset_stack.pop();
1816 result
1817 }
1818
1819 /// Perform prepaint on child elements in a "retryable" manner, so that any side effects
1820 /// of prepaints can be discarded before prepainting again. This is used to support autoscroll
1821 /// where we need to prepaint children to detect the autoscroll bounds, then adjust the
1822 /// element offset and prepaint again. See [`List`] for an example. This method should only be
1823 /// called during the prepaint phase of element drawing.
1824 pub fn transact<T, U>(&mut self, f: impl FnOnce(&mut Self) -> Result<T, U>) -> Result<T, U> {
1825 debug_assert_eq!(
1826 self.window.draw_phase,
1827 DrawPhase::Prepaint,
1828 "this method can only be called during prepaint"
1829 );
1830 let index = self.prepaint_index();
1831 let result = f(self);
1832 if result.is_err() {
1833 self.window
1834 .next_frame
1835 .hitboxes
1836 .truncate(index.hitboxes_index);
1837 self.window
1838 .next_frame
1839 .tooltip_requests
1840 .truncate(index.tooltips_index);
1841 self.window
1842 .next_frame
1843 .deferred_draws
1844 .truncate(index.deferred_draws_index);
1845 self.window
1846 .next_frame
1847 .dispatch_tree
1848 .truncate(index.dispatch_tree_index);
1849 self.window
1850 .next_frame
1851 .accessed_element_states
1852 .truncate(index.accessed_element_states_index);
1853 self.window
1854 .text_system
1855 .truncate_layouts(index.line_layout_index);
1856 }
1857 result
1858 }
1859
1860 /// When you call this method during [`prepaint`], containing elements will attempt to
1861 /// scroll to cause the specified bounds to become visible. When they decide to autoscroll, they will call
1862 /// [`prepaint`] again with a new set of bounds. See [`List`] for an example of an element
1863 /// that supports this method being called on the elements it contains. This method should only be
1864 /// called during the prepaint phase of element drawing.
1865 pub fn request_autoscroll(&mut self, bounds: Bounds<Pixels>) {
1866 debug_assert_eq!(
1867 self.window.draw_phase,
1868 DrawPhase::Prepaint,
1869 "this method can only be called during prepaint"
1870 );
1871 self.window.requested_autoscroll = Some(bounds);
1872 }
1873
1874 /// This method can be called from a containing element such as [`List`] to support the autoscroll behavior
1875 /// described in [`request_autoscroll`].
1876 pub fn take_autoscroll(&mut self) -> Option<Bounds<Pixels>> {
1877 debug_assert_eq!(
1878 self.window.draw_phase,
1879 DrawPhase::Prepaint,
1880 "this method can only be called during prepaint"
1881 );
1882 self.window.requested_autoscroll.take()
1883 }
1884
1885 /// Remove an asset from GPUI's cache
1886 pub fn remove_cached_asset<A: Asset + 'static>(
1887 &mut self,
1888 source: &A::Source,
1889 ) -> Option<A::Output> {
1890 self.asset_cache.remove::<A>(source)
1891 }
1892
1893 /// Asynchronously load an asset, if the asset hasn't finished loading this will return None.
1894 /// Your view will be re-drawn once the asset has finished loading.
1895 ///
1896 /// Note that the multiple calls to this method will only result in one `Asset::load` call.
1897 /// The results of that call will be cached, and returned on subsequent uses of this API.
1898 ///
1899 /// Use [Self::remove_cached_asset] to reload your asset.
1900 pub fn use_cached_asset<A: Asset + 'static>(
1901 &mut self,
1902 source: &A::Source,
1903 ) -> Option<A::Output> {
1904 self.asset_cache.get::<A>(source).or_else(|| {
1905 if let Some(asset) = self.use_asset::<A>(source) {
1906 self.asset_cache
1907 .insert::<A>(source.to_owned(), asset.clone());
1908 Some(asset)
1909 } else {
1910 None
1911 }
1912 })
1913 }
1914
1915 /// Asynchronously load an asset, if the asset hasn't finished loading this will return None.
1916 /// Your view will be re-drawn once the asset has finished loading.
1917 ///
1918 /// Note that the multiple calls to this method will only result in one `Asset::load` call at a
1919 /// time.
1920 ///
1921 /// This asset will not be cached by default, see [Self::use_cached_asset]
1922 pub fn use_asset<A: Asset + 'static>(&mut self, source: &A::Source) -> Option<A::Output> {
1923 let asset_id = (TypeId::of::<A>(), hash(source));
1924 let mut is_first = false;
1925 let task = self
1926 .loading_assets
1927 .remove(&asset_id)
1928 .map(|boxed_task| *boxed_task.downcast::<Shared<Task<A::Output>>>().unwrap())
1929 .unwrap_or_else(|| {
1930 is_first = true;
1931 let future = A::load(source.clone(), self);
1932 let task = self.background_executor().spawn(future).shared();
1933 task
1934 });
1935
1936 task.clone().now_or_never().or_else(|| {
1937 if is_first {
1938 let parent_id = self.parent_view_id();
1939 self.spawn({
1940 let task = task.clone();
1941 |mut cx| async move {
1942 task.await;
1943
1944 cx.on_next_frame(move |cx| {
1945 if let Some(parent_id) = parent_id {
1946 cx.notify(parent_id)
1947 } else {
1948 cx.refresh()
1949 }
1950 });
1951 }
1952 })
1953 .detach();
1954 }
1955
1956 self.loading_assets.insert(asset_id, Box::new(task));
1957
1958 None
1959 })
1960 }
1961
1962 /// Obtain the current element offset. This method should only be called during the
1963 /// prepaint phase of element drawing.
1964 pub fn element_offset(&self) -> Point<Pixels> {
1965 debug_assert_eq!(
1966 self.window.draw_phase,
1967 DrawPhase::Prepaint,
1968 "this method can only be called during prepaint"
1969 );
1970 self.window()
1971 .element_offset_stack
1972 .last()
1973 .copied()
1974 .unwrap_or_default()
1975 }
1976
1977 /// Obtain the current content mask. This method should only be called during element drawing.
1978 pub fn content_mask(&self) -> ContentMask<Pixels> {
1979 debug_assert!(
1980 matches!(
1981 self.window.draw_phase,
1982 DrawPhase::Prepaint | DrawPhase::Paint
1983 ),
1984 "this method can only be called during prepaint, or paint"
1985 );
1986 self.window()
1987 .content_mask_stack
1988 .last()
1989 .cloned()
1990 .unwrap_or_else(|| ContentMask {
1991 bounds: Bounds {
1992 origin: Point::default(),
1993 size: self.window().viewport_size,
1994 },
1995 })
1996 }
1997
1998 /// Provide elements in the called function with a new namespace in which their identiers must be unique.
1999 /// This can be used within a custom element to distinguish multiple sets of child elements.
2000 pub fn with_element_namespace<R>(
2001 &mut self,
2002 element_id: impl Into<ElementId>,
2003 f: impl FnOnce(&mut Self) -> R,
2004 ) -> R {
2005 self.window.element_id_stack.push(element_id.into());
2006 let result = f(self);
2007 self.window.element_id_stack.pop();
2008 result
2009 }
2010
2011 /// Updates or initializes state for an element with the given id that lives across multiple
2012 /// frames. If an element with this ID existed in the rendered frame, its state will be passed
2013 /// to the given closure. The state returned by the closure will be stored so it can be referenced
2014 /// when drawing the next frame. This method should only be called as part of element drawing.
2015 pub fn with_element_state<S, R>(
2016 &mut self,
2017 global_id: &GlobalElementId,
2018 f: impl FnOnce(Option<S>, &mut Self) -> (R, S),
2019 ) -> R
2020 where
2021 S: 'static,
2022 {
2023 debug_assert!(
2024 matches!(
2025 self.window.draw_phase,
2026 DrawPhase::Prepaint | DrawPhase::Paint
2027 ),
2028 "this method can only be called during request_layout, prepaint, or paint"
2029 );
2030
2031 let key = (GlobalElementId(global_id.0.clone()), TypeId::of::<S>());
2032 self.window
2033 .next_frame
2034 .accessed_element_states
2035 .push((GlobalElementId(key.0.clone()), TypeId::of::<S>()));
2036
2037 if let Some(any) = self
2038 .window
2039 .next_frame
2040 .element_states
2041 .remove(&key)
2042 .or_else(|| self.window.rendered_frame.element_states.remove(&key))
2043 {
2044 let ElementStateBox {
2045 inner,
2046 #[cfg(debug_assertions)]
2047 type_name,
2048 } = any;
2049 // Using the extra inner option to avoid needing to reallocate a new box.
2050 let mut state_box = inner
2051 .downcast::<Option<S>>()
2052 .map_err(|_| {
2053 #[cfg(debug_assertions)]
2054 {
2055 anyhow::anyhow!(
2056 "invalid element state type for id, requested {:?}, actual: {:?}",
2057 std::any::type_name::<S>(),
2058 type_name
2059 )
2060 }
2061
2062 #[cfg(not(debug_assertions))]
2063 {
2064 anyhow::anyhow!(
2065 "invalid element state type for id, requested {:?}",
2066 std::any::type_name::<S>(),
2067 )
2068 }
2069 })
2070 .unwrap();
2071
2072 let state = state_box.take().expect(
2073 "reentrant call to with_element_state for the same state type and element id",
2074 );
2075 let (result, state) = f(Some(state), self);
2076 state_box.replace(state);
2077 self.window.next_frame.element_states.insert(
2078 key,
2079 ElementStateBox {
2080 inner: state_box,
2081 #[cfg(debug_assertions)]
2082 type_name,
2083 },
2084 );
2085 result
2086 } else {
2087 let (result, state) = f(None, self);
2088 self.window.next_frame.element_states.insert(
2089 key,
2090 ElementStateBox {
2091 inner: Box::new(Some(state)),
2092 #[cfg(debug_assertions)]
2093 type_name: std::any::type_name::<S>(),
2094 },
2095 );
2096 result
2097 }
2098 }
2099
2100 /// A variant of `with_element_state` that allows the element's id to be optional. This is a convenience
2101 /// method for elements where the element id may or may not be assigned. Prefer using `with_element_state`
2102 /// when the element is guaranteed to have an id.
2103 pub fn with_optional_element_state<S, R>(
2104 &mut self,
2105 global_id: Option<&GlobalElementId>,
2106 f: impl FnOnce(Option<Option<S>>, &mut Self) -> (R, Option<S>),
2107 ) -> R
2108 where
2109 S: 'static,
2110 {
2111 debug_assert!(
2112 matches!(
2113 self.window.draw_phase,
2114 DrawPhase::Prepaint | DrawPhase::Paint
2115 ),
2116 "this method can only be called during request_layout, prepaint, or paint"
2117 );
2118
2119 if let Some(global_id) = global_id {
2120 self.with_element_state(global_id, |state, cx| {
2121 let (result, state) = f(Some(state), cx);
2122 let state =
2123 state.expect("you must return some state when you pass some element id");
2124 (result, state)
2125 })
2126 } else {
2127 let (result, state) = f(None, self);
2128 debug_assert!(
2129 state.is_none(),
2130 "you must not return an element state when passing None for the global id"
2131 );
2132 result
2133 }
2134 }
2135
2136 /// Defers the drawing of the given element, scheduling it to be painted on top of the currently-drawn tree
2137 /// at a later time. The `priority` parameter determines the drawing order relative to other deferred elements,
2138 /// with higher values being drawn on top.
2139 ///
2140 /// This method should only be called as part of the prepaint phase of element drawing.
2141 pub fn defer_draw(
2142 &mut self,
2143 element: AnyElement,
2144 absolute_offset: Point<Pixels>,
2145 priority: usize,
2146 ) {
2147 let window = &mut self.window;
2148 debug_assert_eq!(
2149 window.draw_phase,
2150 DrawPhase::Prepaint,
2151 "this method can only be called during request_layout or prepaint"
2152 );
2153 let parent_node = window.next_frame.dispatch_tree.active_node_id().unwrap();
2154 window.next_frame.deferred_draws.push(DeferredDraw {
2155 parent_node,
2156 element_id_stack: window.element_id_stack.clone(),
2157 text_style_stack: window.text_style_stack.clone(),
2158 priority,
2159 element: Some(element),
2160 absolute_offset,
2161 prepaint_range: PrepaintStateIndex::default()..PrepaintStateIndex::default(),
2162 paint_range: PaintIndex::default()..PaintIndex::default(),
2163 });
2164 }
2165
2166 /// Creates a new painting layer for the specified bounds. A "layer" is a batch
2167 /// of geometry that are non-overlapping and have the same draw order. This is typically used
2168 /// for performance reasons.
2169 ///
2170 /// This method should only be called as part of the paint phase of element drawing.
2171 pub fn paint_layer<R>(&mut self, bounds: Bounds<Pixels>, f: impl FnOnce(&mut Self) -> R) -> R {
2172 debug_assert_eq!(
2173 self.window.draw_phase,
2174 DrawPhase::Paint,
2175 "this method can only be called during paint"
2176 );
2177
2178 let scale_factor = self.scale_factor();
2179 let content_mask = self.content_mask();
2180 let clipped_bounds = bounds.intersect(&content_mask.bounds);
2181 if !clipped_bounds.is_empty() {
2182 self.window
2183 .next_frame
2184 .scene
2185 .push_layer(clipped_bounds.scale(scale_factor));
2186 }
2187
2188 let result = f(self);
2189
2190 if !clipped_bounds.is_empty() {
2191 self.window.next_frame.scene.pop_layer();
2192 }
2193
2194 result
2195 }
2196
2197 /// Paint one or more drop shadows into the scene for the next frame at the current z-index.
2198 ///
2199 /// This method should only be called as part of the paint phase of element drawing.
2200 pub fn paint_shadows(
2201 &mut self,
2202 bounds: Bounds<Pixels>,
2203 corner_radii: Corners<Pixels>,
2204 shadows: &[BoxShadow],
2205 ) {
2206 debug_assert_eq!(
2207 self.window.draw_phase,
2208 DrawPhase::Paint,
2209 "this method can only be called during paint"
2210 );
2211
2212 let scale_factor = self.scale_factor();
2213 let content_mask = self.content_mask();
2214 for shadow in shadows {
2215 let mut shadow_bounds = bounds;
2216 shadow_bounds.origin += shadow.offset;
2217 shadow_bounds.dilate(shadow.spread_radius);
2218 self.window.next_frame.scene.insert_primitive(Shadow {
2219 order: 0,
2220 blur_radius: shadow.blur_radius.scale(scale_factor),
2221 bounds: shadow_bounds.scale(scale_factor),
2222 content_mask: content_mask.scale(scale_factor),
2223 corner_radii: corner_radii.scale(scale_factor),
2224 color: shadow.color,
2225 });
2226 }
2227 }
2228
2229 /// Paint one or more quads into the scene for the next frame at the current stacking context.
2230 /// Quads are colored rectangular regions with an optional background, border, and corner radius.
2231 /// see [`fill`](crate::fill), [`outline`](crate::outline), and [`quad`](crate::quad) to construct this type.
2232 ///
2233 /// This method should only be called as part of the paint phase of element drawing.
2234 pub fn paint_quad(&mut self, quad: PaintQuad) {
2235 debug_assert_eq!(
2236 self.window.draw_phase,
2237 DrawPhase::Paint,
2238 "this method can only be called during paint"
2239 );
2240
2241 let scale_factor = self.scale_factor();
2242 let content_mask = self.content_mask();
2243 self.window.next_frame.scene.insert_primitive(Quad {
2244 order: 0,
2245 pad: 0,
2246 bounds: quad.bounds.scale(scale_factor),
2247 content_mask: content_mask.scale(scale_factor),
2248 background: quad.background,
2249 border_color: quad.border_color,
2250 corner_radii: quad.corner_radii.scale(scale_factor),
2251 border_widths: quad.border_widths.scale(scale_factor),
2252 });
2253 }
2254
2255 /// Paint the given `Path` into the scene for the next frame at the current z-index.
2256 ///
2257 /// This method should only be called as part of the paint phase of element drawing.
2258 pub fn paint_path(&mut self, mut path: Path<Pixels>, color: impl Into<Hsla>) {
2259 debug_assert_eq!(
2260 self.window.draw_phase,
2261 DrawPhase::Paint,
2262 "this method can only be called during paint"
2263 );
2264
2265 let scale_factor = self.scale_factor();
2266 let content_mask = self.content_mask();
2267 path.content_mask = content_mask;
2268 path.color = color.into();
2269 self.window
2270 .next_frame
2271 .scene
2272 .insert_primitive(path.scale(scale_factor));
2273 }
2274
2275 /// Paint an underline into the scene for the next frame at the current z-index.
2276 ///
2277 /// This method should only be called as part of the paint phase of element drawing.
2278 pub fn paint_underline(
2279 &mut self,
2280 origin: Point<Pixels>,
2281 width: Pixels,
2282 style: &UnderlineStyle,
2283 ) {
2284 debug_assert_eq!(
2285 self.window.draw_phase,
2286 DrawPhase::Paint,
2287 "this method can only be called during paint"
2288 );
2289
2290 let scale_factor = self.scale_factor();
2291 let height = if style.wavy {
2292 style.thickness * 3.
2293 } else {
2294 style.thickness
2295 };
2296 let bounds = Bounds {
2297 origin,
2298 size: size(width, height),
2299 };
2300 let content_mask = self.content_mask();
2301
2302 self.window.next_frame.scene.insert_primitive(Underline {
2303 order: 0,
2304 pad: 0,
2305 bounds: bounds.scale(scale_factor),
2306 content_mask: content_mask.scale(scale_factor),
2307 color: style.color.unwrap_or_default(),
2308 thickness: style.thickness.scale(scale_factor),
2309 wavy: style.wavy,
2310 });
2311 }
2312
2313 /// Paint a strikethrough into the scene for the next frame at the current z-index.
2314 ///
2315 /// This method should only be called as part of the paint phase of element drawing.
2316 pub fn paint_strikethrough(
2317 &mut self,
2318 origin: Point<Pixels>,
2319 width: Pixels,
2320 style: &StrikethroughStyle,
2321 ) {
2322 debug_assert_eq!(
2323 self.window.draw_phase,
2324 DrawPhase::Paint,
2325 "this method can only be called during paint"
2326 );
2327
2328 let scale_factor = self.scale_factor();
2329 let height = style.thickness;
2330 let bounds = Bounds {
2331 origin,
2332 size: size(width, height),
2333 };
2334 let content_mask = self.content_mask();
2335
2336 self.window.next_frame.scene.insert_primitive(Underline {
2337 order: 0,
2338 pad: 0,
2339 bounds: bounds.scale(scale_factor),
2340 content_mask: content_mask.scale(scale_factor),
2341 thickness: style.thickness.scale(scale_factor),
2342 color: style.color.unwrap_or_default(),
2343 wavy: false,
2344 });
2345 }
2346
2347 /// Paints a monochrome (non-emoji) glyph into the scene for the next frame at the current z-index.
2348 ///
2349 /// The y component of the origin is the baseline of the glyph.
2350 /// You should generally prefer to use the [`ShapedLine::paint`](crate::ShapedLine::paint) or
2351 /// [`WrappedLine::paint`](crate::WrappedLine::paint) methods in the [`TextSystem`](crate::TextSystem).
2352 /// This method is only useful if you need to paint a single glyph that has already been shaped.
2353 ///
2354 /// This method should only be called as part of the paint phase of element drawing.
2355 pub fn paint_glyph(
2356 &mut self,
2357 origin: Point<Pixels>,
2358 font_id: FontId,
2359 glyph_id: GlyphId,
2360 font_size: Pixels,
2361 color: Hsla,
2362 ) -> Result<()> {
2363 debug_assert_eq!(
2364 self.window.draw_phase,
2365 DrawPhase::Paint,
2366 "this method can only be called during paint"
2367 );
2368
2369 let scale_factor = self.scale_factor();
2370 let glyph_origin = origin.scale(scale_factor);
2371 let subpixel_variant = Point {
2372 x: (glyph_origin.x.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
2373 y: (glyph_origin.y.0.fract() * SUBPIXEL_VARIANTS as f32).floor() as u8,
2374 };
2375 let params = RenderGlyphParams {
2376 font_id,
2377 glyph_id,
2378 font_size,
2379 subpixel_variant,
2380 scale_factor,
2381 is_emoji: false,
2382 };
2383
2384 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
2385 if !raster_bounds.is_zero() {
2386 let tile = self
2387 .window
2388 .sprite_atlas
2389 .get_or_insert_with(¶ms.clone().into(), &mut || {
2390 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
2391 Ok(Some((size, Cow::Owned(bytes))))
2392 })?
2393 .expect("Callback above only errors or returns Some");
2394 let bounds = Bounds {
2395 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
2396 size: tile.bounds.size.map(Into::into),
2397 };
2398 let content_mask = self.content_mask().scale(scale_factor);
2399 self.window
2400 .next_frame
2401 .scene
2402 .insert_primitive(MonochromeSprite {
2403 order: 0,
2404 pad: 0,
2405 bounds,
2406 content_mask,
2407 color,
2408 tile,
2409 transformation: TransformationMatrix::unit(),
2410 });
2411 }
2412 Ok(())
2413 }
2414
2415 /// Paints an emoji glyph into the scene for the next frame at the current z-index.
2416 ///
2417 /// The y component of the origin is the baseline of the glyph.
2418 /// You should generally prefer to use the [`ShapedLine::paint`](crate::ShapedLine::paint) or
2419 /// [`WrappedLine::paint`](crate::WrappedLine::paint) methods in the [`TextSystem`](crate::TextSystem).
2420 /// This method is only useful if you need to paint a single emoji that has already been shaped.
2421 ///
2422 /// This method should only be called as part of the paint phase of element drawing.
2423 pub fn paint_emoji(
2424 &mut self,
2425 origin: Point<Pixels>,
2426 font_id: FontId,
2427 glyph_id: GlyphId,
2428 font_size: Pixels,
2429 ) -> Result<()> {
2430 debug_assert_eq!(
2431 self.window.draw_phase,
2432 DrawPhase::Paint,
2433 "this method can only be called during paint"
2434 );
2435
2436 let scale_factor = self.scale_factor();
2437 let glyph_origin = origin.scale(scale_factor);
2438 let params = RenderGlyphParams {
2439 font_id,
2440 glyph_id,
2441 font_size,
2442 // We don't render emojis with subpixel variants.
2443 subpixel_variant: Default::default(),
2444 scale_factor,
2445 is_emoji: true,
2446 };
2447
2448 let raster_bounds = self.text_system().raster_bounds(¶ms)?;
2449 if !raster_bounds.is_zero() {
2450 let tile = self
2451 .window
2452 .sprite_atlas
2453 .get_or_insert_with(¶ms.clone().into(), &mut || {
2454 let (size, bytes) = self.text_system().rasterize_glyph(¶ms)?;
2455 Ok(Some((size, Cow::Owned(bytes))))
2456 })?
2457 .expect("Callback above only errors or returns Some");
2458
2459 let bounds = Bounds {
2460 origin: glyph_origin.map(|px| px.floor()) + raster_bounds.origin.map(Into::into),
2461 size: tile.bounds.size.map(Into::into),
2462 };
2463 let content_mask = self.content_mask().scale(scale_factor);
2464
2465 self.window
2466 .next_frame
2467 .scene
2468 .insert_primitive(PolychromeSprite {
2469 order: 0,
2470 grayscale: false,
2471 bounds,
2472 corner_radii: Default::default(),
2473 content_mask,
2474 tile,
2475 });
2476 }
2477 Ok(())
2478 }
2479
2480 /// Paint a monochrome SVG into the scene for the next frame at the current stacking context.
2481 ///
2482 /// This method should only be called as part of the paint phase of element drawing.
2483 pub fn paint_svg(
2484 &mut self,
2485 bounds: Bounds<Pixels>,
2486 path: SharedString,
2487 transformation: TransformationMatrix,
2488 color: Hsla,
2489 ) -> Result<()> {
2490 debug_assert_eq!(
2491 self.window.draw_phase,
2492 DrawPhase::Paint,
2493 "this method can only be called during paint"
2494 );
2495
2496 let scale_factor = self.scale_factor();
2497 let bounds = bounds.scale(scale_factor);
2498 // Render the SVG at twice the size to get a higher quality result.
2499 let params = RenderSvgParams {
2500 path,
2501 size: bounds
2502 .size
2503 .map(|pixels| DevicePixels::from((pixels.0 * 2.).ceil() as i32)),
2504 };
2505
2506 let Some(tile) =
2507 self.window
2508 .sprite_atlas
2509 .get_or_insert_with(¶ms.clone().into(), &mut || {
2510 let Some(bytes) = self.svg_renderer.render(¶ms)? else {
2511 return Ok(None);
2512 };
2513 Ok(Some((params.size, Cow::Owned(bytes))))
2514 })?
2515 else {
2516 return Ok(());
2517 };
2518 let content_mask = self.content_mask().scale(scale_factor);
2519
2520 self.window
2521 .next_frame
2522 .scene
2523 .insert_primitive(MonochromeSprite {
2524 order: 0,
2525 pad: 0,
2526 bounds,
2527 content_mask,
2528 color,
2529 tile,
2530 transformation,
2531 });
2532
2533 Ok(())
2534 }
2535
2536 /// Paint an image into the scene for the next frame at the current z-index.
2537 ///
2538 /// This method should only be called as part of the paint phase of element drawing.
2539 pub fn paint_image(
2540 &mut self,
2541 bounds: Bounds<Pixels>,
2542 corner_radii: Corners<Pixels>,
2543 data: Arc<ImageData>,
2544 grayscale: bool,
2545 ) -> Result<()> {
2546 debug_assert_eq!(
2547 self.window.draw_phase,
2548 DrawPhase::Paint,
2549 "this method can only be called during paint"
2550 );
2551
2552 let scale_factor = self.scale_factor();
2553 let bounds = bounds.scale(scale_factor);
2554 let params = RenderImageParams { image_id: data.id };
2555
2556 let tile = self
2557 .window
2558 .sprite_atlas
2559 .get_or_insert_with(¶ms.clone().into(), &mut || {
2560 Ok(Some((data.size(), Cow::Borrowed(data.as_bytes()))))
2561 })?
2562 .expect("Callback above only returns Some");
2563 let content_mask = self.content_mask().scale(scale_factor);
2564 let corner_radii = corner_radii.scale(scale_factor);
2565
2566 self.window
2567 .next_frame
2568 .scene
2569 .insert_primitive(PolychromeSprite {
2570 order: 0,
2571 grayscale,
2572 bounds,
2573 content_mask,
2574 corner_radii,
2575 tile,
2576 });
2577 Ok(())
2578 }
2579
2580 /// Paint a surface into the scene for the next frame at the current z-index.
2581 ///
2582 /// This method should only be called as part of the paint phase of element drawing.
2583 #[cfg(target_os = "macos")]
2584 pub fn paint_surface(&mut self, bounds: Bounds<Pixels>, image_buffer: CVImageBuffer) {
2585 debug_assert_eq!(
2586 self.window.draw_phase,
2587 DrawPhase::Paint,
2588 "this method can only be called during paint"
2589 );
2590
2591 let scale_factor = self.scale_factor();
2592 let bounds = bounds.scale(scale_factor);
2593 let content_mask = self.content_mask().scale(scale_factor);
2594 self.window
2595 .next_frame
2596 .scene
2597 .insert_primitive(crate::Surface {
2598 order: 0,
2599 bounds,
2600 content_mask,
2601 image_buffer,
2602 });
2603 }
2604
2605 #[must_use]
2606 /// Add a node to the layout tree for the current frame. Takes the `Style` of the element for which
2607 /// layout is being requested, along with the layout ids of any children. This method is called during
2608 /// calls to the [`Element::request_layout`] trait method and enables any element to participate in layout.
2609 ///
2610 /// This method should only be called as part of the request_layout or prepaint phase of element drawing.
2611 pub fn request_layout(
2612 &mut self,
2613 style: Style,
2614 children: impl IntoIterator<Item = LayoutId>,
2615 ) -> LayoutId {
2616 debug_assert_eq!(
2617 self.window.draw_phase,
2618 DrawPhase::Prepaint,
2619 "this method can only be called during request_layout, or prepaint"
2620 );
2621
2622 self.app.layout_id_buffer.clear();
2623 self.app.layout_id_buffer.extend(children);
2624 let rem_size = self.rem_size();
2625
2626 self.window.layout_engine.as_mut().unwrap().request_layout(
2627 style,
2628 rem_size,
2629 &self.app.layout_id_buffer,
2630 )
2631 }
2632
2633 /// Add a node to the layout tree for the current frame. Instead of taking a `Style` and children,
2634 /// this variant takes a function that is invoked during layout so you can use arbitrary logic to
2635 /// determine the element's size. One place this is used internally is when measuring text.
2636 ///
2637 /// The given closure is invoked at layout time with the known dimensions and available space and
2638 /// returns a `Size`.
2639 ///
2640 /// This method should only be called as part of the request_layout or prepaint phase of element drawing.
2641 pub fn request_measured_layout<
2642 F: FnMut(Size<Option<Pixels>>, Size<AvailableSpace>, &mut WindowContext) -> Size<Pixels>
2643 + 'static,
2644 >(
2645 &mut self,
2646 style: Style,
2647 measure: F,
2648 ) -> LayoutId {
2649 debug_assert_eq!(
2650 self.window.draw_phase,
2651 DrawPhase::Prepaint,
2652 "this method can only be called during request_layout, or prepaint"
2653 );
2654
2655 let rem_size = self.rem_size();
2656 self.window
2657 .layout_engine
2658 .as_mut()
2659 .unwrap()
2660 .request_measured_layout(style, rem_size, measure)
2661 }
2662
2663 /// Compute the layout for the given id within the given available space.
2664 /// This method is called for its side effect, typically by the framework prior to painting.
2665 /// After calling it, you can request the bounds of the given layout node id or any descendant.
2666 ///
2667 /// This method should only be called as part of the prepaint phase of element drawing.
2668 pub fn compute_layout(&mut self, layout_id: LayoutId, available_space: Size<AvailableSpace>) {
2669 debug_assert_eq!(
2670 self.window.draw_phase,
2671 DrawPhase::Prepaint,
2672 "this method can only be called during request_layout, or prepaint"
2673 );
2674
2675 let mut layout_engine = self.window.layout_engine.take().unwrap();
2676 layout_engine.compute_layout(layout_id, available_space, self);
2677 self.window.layout_engine = Some(layout_engine);
2678 }
2679
2680 /// Obtain the bounds computed for the given LayoutId relative to the window. This method will usually be invoked by
2681 /// GPUI itself automatically in order to pass your element its `Bounds` automatically.
2682 ///
2683 /// This method should only be called as part of element drawing.
2684 pub fn layout_bounds(&mut self, layout_id: LayoutId) -> Bounds<Pixels> {
2685 debug_assert_eq!(
2686 self.window.draw_phase,
2687 DrawPhase::Prepaint,
2688 "this method can only be called during request_layout, prepaint, or paint"
2689 );
2690
2691 let mut bounds = self
2692 .window
2693 .layout_engine
2694 .as_mut()
2695 .unwrap()
2696 .layout_bounds(layout_id)
2697 .map(Into::into);
2698 bounds.origin += self.element_offset();
2699 bounds
2700 }
2701
2702 /// This method should be called during `prepaint`. You can use
2703 /// the returned [Hitbox] during `paint` or in an event handler
2704 /// to determine whether the inserted hitbox was the topmost.
2705 ///
2706 /// This method should only be called as part of the prepaint phase of element drawing.
2707 pub fn insert_hitbox(&mut self, bounds: Bounds<Pixels>, opaque: bool) -> Hitbox {
2708 debug_assert_eq!(
2709 self.window.draw_phase,
2710 DrawPhase::Prepaint,
2711 "this method can only be called during prepaint"
2712 );
2713
2714 let content_mask = self.content_mask();
2715 let window = &mut self.window;
2716 let id = window.next_hitbox_id;
2717 window.next_hitbox_id.0 += 1;
2718 let hitbox = Hitbox {
2719 id,
2720 bounds,
2721 content_mask,
2722 opaque,
2723 };
2724 window.next_frame.hitboxes.push(hitbox.clone());
2725 hitbox
2726 }
2727
2728 /// Sets the key context for the current element. This context will be used to translate
2729 /// keybindings into actions.
2730 ///
2731 /// This method should only be called as part of the paint phase of element drawing.
2732 pub fn set_key_context(&mut self, context: KeyContext) {
2733 debug_assert_eq!(
2734 self.window.draw_phase,
2735 DrawPhase::Paint,
2736 "this method can only be called during paint"
2737 );
2738 self.window
2739 .next_frame
2740 .dispatch_tree
2741 .set_key_context(context);
2742 }
2743
2744 /// Sets the focus handle for the current element. This handle will be used to manage focus state
2745 /// and keyboard event dispatch for the element.
2746 ///
2747 /// This method should only be called as part of the paint phase of element drawing.
2748 pub fn set_focus_handle(&mut self, focus_handle: &FocusHandle) {
2749 debug_assert_eq!(
2750 self.window.draw_phase,
2751 DrawPhase::Paint,
2752 "this method can only be called during paint"
2753 );
2754 self.window
2755 .next_frame
2756 .dispatch_tree
2757 .set_focus_id(focus_handle.id);
2758 }
2759
2760 /// Sets the view id for the current element, which will be used to manage view caching.
2761 ///
2762 /// This method should only be called as part of element prepaint. We plan on removing this
2763 /// method eventually when we solve some issues that require us to construct editor elements
2764 /// directly instead of always using editors via views.
2765 pub fn set_view_id(&mut self, view_id: EntityId) {
2766 debug_assert_eq!(
2767 self.window.draw_phase,
2768 DrawPhase::Prepaint,
2769 "this method can only be called during prepaint"
2770 );
2771 self.window.next_frame.dispatch_tree.set_view_id(view_id);
2772 }
2773
2774 /// Get the last view id for the current element
2775 pub fn parent_view_id(&mut self) -> Option<EntityId> {
2776 self.window.next_frame.dispatch_tree.parent_view_id()
2777 }
2778
2779 /// Sets an input handler, such as [`ElementInputHandler`][element_input_handler], which interfaces with the
2780 /// platform to receive textual input with proper integration with concerns such
2781 /// as IME interactions. This handler will be active for the upcoming frame until the following frame is
2782 /// rendered.
2783 ///
2784 /// This method should only be called as part of the paint phase of element drawing.
2785 ///
2786 /// [element_input_handler]: crate::ElementInputHandler
2787 pub fn handle_input(&mut self, focus_handle: &FocusHandle, input_handler: impl InputHandler) {
2788 debug_assert_eq!(
2789 self.window.draw_phase,
2790 DrawPhase::Paint,
2791 "this method can only be called during paint"
2792 );
2793
2794 if focus_handle.is_focused(self) {
2795 let cx = self.to_async();
2796 self.window
2797 .next_frame
2798 .input_handlers
2799 .push(Some(PlatformInputHandler::new(cx, Box::new(input_handler))));
2800 }
2801 }
2802
2803 /// Register a mouse event listener on the window for the next frame. The type of event
2804 /// is determined by the first parameter of the given listener. When the next frame is rendered
2805 /// the listener will be cleared.
2806 ///
2807 /// This method should only be called as part of the paint phase of element drawing.
2808 pub fn on_mouse_event<Event: MouseEvent>(
2809 &mut self,
2810 mut handler: impl FnMut(&Event, DispatchPhase, &mut WindowContext) + 'static,
2811 ) {
2812 debug_assert_eq!(
2813 self.window.draw_phase,
2814 DrawPhase::Paint,
2815 "this method can only be called during paint"
2816 );
2817
2818 self.window.next_frame.mouse_listeners.push(Some(Box::new(
2819 move |event: &dyn Any, phase: DispatchPhase, cx: &mut WindowContext<'_>| {
2820 if let Some(event) = event.downcast_ref() {
2821 handler(event, phase, cx)
2822 }
2823 },
2824 )));
2825 }
2826
2827 /// Register a key event listener on the window for the next frame. The type of event
2828 /// is determined by the first parameter of the given listener. When the next frame is rendered
2829 /// the listener will be cleared.
2830 ///
2831 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
2832 /// a specific need to register a global listener.
2833 ///
2834 /// This method should only be called as part of the paint phase of element drawing.
2835 pub fn on_key_event<Event: KeyEvent>(
2836 &mut self,
2837 listener: impl Fn(&Event, DispatchPhase, &mut WindowContext) + 'static,
2838 ) {
2839 debug_assert_eq!(
2840 self.window.draw_phase,
2841 DrawPhase::Paint,
2842 "this method can only be called during paint"
2843 );
2844
2845 self.window.next_frame.dispatch_tree.on_key_event(Rc::new(
2846 move |event: &dyn Any, phase, cx: &mut WindowContext<'_>| {
2847 if let Some(event) = event.downcast_ref::<Event>() {
2848 listener(event, phase, cx)
2849 }
2850 },
2851 ));
2852 }
2853
2854 /// Register a modifiers changed event listener on the window for the next frame.
2855 ///
2856 /// This is a fairly low-level method, so prefer using event handlers on elements unless you have
2857 /// a specific need to register a global listener.
2858 ///
2859 /// This method should only be called as part of the paint phase of element drawing.
2860 pub fn on_modifiers_changed(
2861 &mut self,
2862 listener: impl Fn(&ModifiersChangedEvent, &mut WindowContext) + 'static,
2863 ) {
2864 debug_assert_eq!(
2865 self.window.draw_phase,
2866 DrawPhase::Paint,
2867 "this method can only be called during paint"
2868 );
2869
2870 self.window
2871 .next_frame
2872 .dispatch_tree
2873 .on_modifiers_changed(Rc::new(
2874 move |event: &ModifiersChangedEvent, cx: &mut WindowContext<'_>| {
2875 listener(event, cx)
2876 },
2877 ));
2878 }
2879
2880 fn reset_cursor_style(&self) {
2881 // Set the cursor only if we're the active window.
2882 if self.is_window_active() {
2883 let style = self
2884 .window
2885 .rendered_frame
2886 .cursor_styles
2887 .iter()
2888 .rev()
2889 .find(|request| request.hitbox_id.is_hovered(self))
2890 .map(|request| request.style)
2891 .unwrap_or(CursorStyle::Arrow);
2892 self.platform.set_cursor_style(style);
2893 }
2894 }
2895
2896 /// Dispatch a given keystroke as though the user had typed it.
2897 /// You can create a keystroke with Keystroke::parse("").
2898 pub fn dispatch_keystroke(&mut self, keystroke: Keystroke) -> bool {
2899 let keystroke = keystroke.with_simulated_ime();
2900 let result = self.dispatch_event(PlatformInput::KeyDown(KeyDownEvent {
2901 keystroke: keystroke.clone(),
2902 is_held: false,
2903 }));
2904 if !result.propagate {
2905 return true;
2906 }
2907
2908 if let Some(input) = keystroke.ime_key {
2909 if let Some(mut input_handler) = self.window.platform_window.take_input_handler() {
2910 input_handler.dispatch_input(&input, self);
2911 self.window.platform_window.set_input_handler(input_handler);
2912 return true;
2913 }
2914 }
2915
2916 false
2917 }
2918
2919 /// Represent this action as a key binding string, to display in the UI.
2920 pub fn keystroke_text_for(&self, action: &dyn Action) -> String {
2921 self.bindings_for_action(action)
2922 .into_iter()
2923 .next()
2924 .map(|binding| {
2925 binding
2926 .keystrokes()
2927 .iter()
2928 .map(ToString::to_string)
2929 .collect::<Vec<_>>()
2930 .join(" ")
2931 })
2932 .unwrap_or_else(|| action.name().to_string())
2933 }
2934
2935 /// Dispatch a mouse or keyboard event on the window.
2936 #[profiling::function]
2937 pub fn dispatch_event(&mut self, event: PlatformInput) -> DispatchEventResult {
2938 self.window.last_input_timestamp.set(Instant::now());
2939 // Handlers may set this to false by calling `stop_propagation`.
2940 self.app.propagate_event = true;
2941 // Handlers may set this to true by calling `prevent_default`.
2942 self.window.default_prevented = false;
2943
2944 let event = match event {
2945 // Track the mouse position with our own state, since accessing the platform
2946 // API for the mouse position can only occur on the main thread.
2947 PlatformInput::MouseMove(mouse_move) => {
2948 self.window.mouse_position = mouse_move.position;
2949 self.window.modifiers = mouse_move.modifiers;
2950 PlatformInput::MouseMove(mouse_move)
2951 }
2952 PlatformInput::MouseDown(mouse_down) => {
2953 self.window.mouse_position = mouse_down.position;
2954 self.window.modifiers = mouse_down.modifiers;
2955 PlatformInput::MouseDown(mouse_down)
2956 }
2957 PlatformInput::MouseUp(mouse_up) => {
2958 self.window.mouse_position = mouse_up.position;
2959 self.window.modifiers = mouse_up.modifiers;
2960 PlatformInput::MouseUp(mouse_up)
2961 }
2962 PlatformInput::MouseExited(mouse_exited) => {
2963 self.window.modifiers = mouse_exited.modifiers;
2964 PlatformInput::MouseExited(mouse_exited)
2965 }
2966 PlatformInput::ModifiersChanged(modifiers_changed) => {
2967 self.window.modifiers = modifiers_changed.modifiers;
2968 PlatformInput::ModifiersChanged(modifiers_changed)
2969 }
2970 PlatformInput::ScrollWheel(scroll_wheel) => {
2971 self.window.mouse_position = scroll_wheel.position;
2972 self.window.modifiers = scroll_wheel.modifiers;
2973 PlatformInput::ScrollWheel(scroll_wheel)
2974 }
2975 // Translate dragging and dropping of external files from the operating system
2976 // to internal drag and drop events.
2977 PlatformInput::FileDrop(file_drop) => match file_drop {
2978 FileDropEvent::Entered { position, paths } => {
2979 self.window.mouse_position = position;
2980 if self.active_drag.is_none() {
2981 self.active_drag = Some(AnyDrag {
2982 value: Box::new(paths.clone()),
2983 view: self.new_view(|_| paths).into(),
2984 cursor_offset: position,
2985 });
2986 }
2987 PlatformInput::MouseMove(MouseMoveEvent {
2988 position,
2989 pressed_button: Some(MouseButton::Left),
2990 modifiers: Modifiers::default(),
2991 })
2992 }
2993 FileDropEvent::Pending { position } => {
2994 self.window.mouse_position = position;
2995 PlatformInput::MouseMove(MouseMoveEvent {
2996 position,
2997 pressed_button: Some(MouseButton::Left),
2998 modifiers: Modifiers::default(),
2999 })
3000 }
3001 FileDropEvent::Submit { position } => {
3002 self.activate(true);
3003 self.window.mouse_position = position;
3004 PlatformInput::MouseUp(MouseUpEvent {
3005 button: MouseButton::Left,
3006 position,
3007 modifiers: Modifiers::default(),
3008 click_count: 1,
3009 })
3010 }
3011 FileDropEvent::Exited => {
3012 self.active_drag.take();
3013 PlatformInput::FileDrop(FileDropEvent::Exited)
3014 }
3015 },
3016 PlatformInput::KeyDown(_) | PlatformInput::KeyUp(_) => event,
3017 };
3018
3019 if let Some(any_mouse_event) = event.mouse_event() {
3020 self.dispatch_mouse_event(any_mouse_event);
3021 } else if let Some(any_key_event) = event.keyboard_event() {
3022 self.dispatch_key_event(any_key_event);
3023 }
3024
3025 DispatchEventResult {
3026 propagate: self.app.propagate_event,
3027 default_prevented: self.window.default_prevented,
3028 }
3029 }
3030
3031 fn dispatch_mouse_event(&mut self, event: &dyn Any) {
3032 let hit_test = self.window.rendered_frame.hit_test(self.mouse_position());
3033 if hit_test != self.window.mouse_hit_test {
3034 self.window.mouse_hit_test = hit_test;
3035 self.reset_cursor_style();
3036 }
3037
3038 let mut mouse_listeners = mem::take(&mut self.window.rendered_frame.mouse_listeners);
3039
3040 // Capture phase, events bubble from back to front. Handlers for this phase are used for
3041 // special purposes, such as detecting events outside of a given Bounds.
3042 for listener in &mut mouse_listeners {
3043 let listener = listener.as_mut().unwrap();
3044 listener(event, DispatchPhase::Capture, self);
3045 if !self.app.propagate_event {
3046 break;
3047 }
3048 }
3049
3050 // Bubble phase, where most normal handlers do their work.
3051 if self.app.propagate_event {
3052 for listener in mouse_listeners.iter_mut().rev() {
3053 let listener = listener.as_mut().unwrap();
3054 listener(event, DispatchPhase::Bubble, self);
3055 if !self.app.propagate_event {
3056 break;
3057 }
3058 }
3059 }
3060
3061 self.window.rendered_frame.mouse_listeners = mouse_listeners;
3062
3063 if self.has_active_drag() {
3064 if event.is::<MouseMoveEvent>() {
3065 // If this was a mouse move event, redraw the window so that the
3066 // active drag can follow the mouse cursor.
3067 self.refresh();
3068 } else if event.is::<MouseUpEvent>() {
3069 // If this was a mouse up event, cancel the active drag and redraw
3070 // the window.
3071 self.active_drag = None;
3072 self.refresh();
3073 }
3074 }
3075 }
3076
3077 fn dispatch_key_event(&mut self, event: &dyn Any) {
3078 if self.window.dirty.get() {
3079 self.draw();
3080 }
3081
3082 let node_id = self
3083 .window
3084 .focus
3085 .and_then(|focus_id| {
3086 self.window
3087 .rendered_frame
3088 .dispatch_tree
3089 .focusable_node_id(focus_id)
3090 })
3091 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3092
3093 let dispatch_path = self
3094 .window
3095 .rendered_frame
3096 .dispatch_tree
3097 .dispatch_path(node_id);
3098
3099 if let Some(key_down_event) = event.downcast_ref::<KeyDownEvent>() {
3100 let KeymatchResult { bindings, pending } = self
3101 .window
3102 .rendered_frame
3103 .dispatch_tree
3104 .dispatch_key(&key_down_event.keystroke, &dispatch_path);
3105
3106 if pending {
3107 let mut currently_pending = self.window.pending_input.take().unwrap_or_default();
3108 if currently_pending.focus.is_some() && currently_pending.focus != self.window.focus
3109 {
3110 currently_pending = PendingInput::default();
3111 }
3112 currently_pending.focus = self.window.focus;
3113 currently_pending
3114 .keystrokes
3115 .push(key_down_event.keystroke.clone());
3116 for binding in bindings {
3117 currently_pending.bindings.push(binding);
3118 }
3119
3120 currently_pending.timer = Some(self.spawn(|mut cx| async move {
3121 cx.background_executor.timer(Duration::from_secs(1)).await;
3122 cx.update(move |cx| {
3123 cx.clear_pending_keystrokes();
3124 let Some(currently_pending) = cx.window.pending_input.take() else {
3125 return;
3126 };
3127 cx.replay_pending_input(currently_pending)
3128 })
3129 .log_err();
3130 }));
3131
3132 self.window.pending_input = Some(currently_pending);
3133
3134 self.propagate_event = false;
3135 return;
3136 } else if let Some(currently_pending) = self.window.pending_input.take() {
3137 if bindings
3138 .iter()
3139 .all(|binding| !currently_pending.used_by_binding(binding))
3140 {
3141 self.replay_pending_input(currently_pending)
3142 }
3143 }
3144
3145 if !bindings.is_empty() {
3146 self.clear_pending_keystrokes();
3147 }
3148
3149 self.propagate_event = true;
3150 for binding in bindings {
3151 self.dispatch_action_on_node(node_id, binding.action.as_ref());
3152 if !self.propagate_event {
3153 self.dispatch_keystroke_observers(event, Some(binding.action));
3154 return;
3155 }
3156 }
3157 }
3158
3159 self.dispatch_key_down_up_event(event, &dispatch_path);
3160 if !self.propagate_event {
3161 return;
3162 }
3163
3164 self.dispatch_modifiers_changed_event(event, &dispatch_path);
3165 if !self.propagate_event {
3166 return;
3167 }
3168
3169 self.dispatch_keystroke_observers(event, None);
3170 }
3171
3172 fn dispatch_key_down_up_event(
3173 &mut self,
3174 event: &dyn Any,
3175 dispatch_path: &SmallVec<[DispatchNodeId; 32]>,
3176 ) {
3177 // Capture phase
3178 for node_id in dispatch_path {
3179 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3180
3181 for key_listener in node.key_listeners.clone() {
3182 key_listener(event, DispatchPhase::Capture, self);
3183 if !self.propagate_event {
3184 return;
3185 }
3186 }
3187 }
3188
3189 // Bubble phase
3190 for node_id in dispatch_path.iter().rev() {
3191 // Handle low level key events
3192 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3193 for key_listener in node.key_listeners.clone() {
3194 key_listener(event, DispatchPhase::Bubble, self);
3195 if !self.propagate_event {
3196 return;
3197 }
3198 }
3199 }
3200 }
3201
3202 fn dispatch_modifiers_changed_event(
3203 &mut self,
3204 event: &dyn Any,
3205 dispatch_path: &SmallVec<[DispatchNodeId; 32]>,
3206 ) {
3207 let Some(event) = event.downcast_ref::<ModifiersChangedEvent>() else {
3208 return;
3209 };
3210 for node_id in dispatch_path.iter().rev() {
3211 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3212 for listener in node.modifiers_changed_listeners.clone() {
3213 listener(event, self);
3214 if !self.propagate_event {
3215 return;
3216 }
3217 }
3218 }
3219 }
3220
3221 /// Determine whether a potential multi-stroke key binding is in progress on this window.
3222 pub fn has_pending_keystrokes(&self) -> bool {
3223 self.window
3224 .rendered_frame
3225 .dispatch_tree
3226 .has_pending_keystrokes()
3227 }
3228
3229 fn replay_pending_input(&mut self, currently_pending: PendingInput) {
3230 let node_id = self
3231 .window
3232 .focus
3233 .and_then(|focus_id| {
3234 self.window
3235 .rendered_frame
3236 .dispatch_tree
3237 .focusable_node_id(focus_id)
3238 })
3239 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3240
3241 if self.window.focus != currently_pending.focus {
3242 return;
3243 }
3244
3245 let input = currently_pending.input();
3246
3247 self.propagate_event = true;
3248 for binding in currently_pending.bindings {
3249 self.dispatch_action_on_node(node_id, binding.action.as_ref());
3250 if !self.propagate_event {
3251 return;
3252 }
3253 }
3254
3255 let dispatch_path = self
3256 .window
3257 .rendered_frame
3258 .dispatch_tree
3259 .dispatch_path(node_id);
3260
3261 for keystroke in currently_pending.keystrokes {
3262 let event = KeyDownEvent {
3263 keystroke,
3264 is_held: false,
3265 };
3266
3267 self.dispatch_key_down_up_event(&event, &dispatch_path);
3268 if !self.propagate_event {
3269 return;
3270 }
3271 }
3272
3273 if !input.is_empty() {
3274 if let Some(mut input_handler) = self.window.platform_window.take_input_handler() {
3275 input_handler.dispatch_input(&input, self);
3276 self.window.platform_window.set_input_handler(input_handler)
3277 }
3278 }
3279 }
3280
3281 fn dispatch_action_on_node(&mut self, node_id: DispatchNodeId, action: &dyn Action) {
3282 let dispatch_path = self
3283 .window
3284 .rendered_frame
3285 .dispatch_tree
3286 .dispatch_path(node_id);
3287
3288 // Capture phase for global actions.
3289 self.propagate_event = true;
3290 if let Some(mut global_listeners) = self
3291 .global_action_listeners
3292 .remove(&action.as_any().type_id())
3293 {
3294 for listener in &global_listeners {
3295 listener(action.as_any(), DispatchPhase::Capture, self);
3296 if !self.propagate_event {
3297 break;
3298 }
3299 }
3300
3301 global_listeners.extend(
3302 self.global_action_listeners
3303 .remove(&action.as_any().type_id())
3304 .unwrap_or_default(),
3305 );
3306
3307 self.global_action_listeners
3308 .insert(action.as_any().type_id(), global_listeners);
3309 }
3310
3311 if !self.propagate_event {
3312 return;
3313 }
3314
3315 // Capture phase for window actions.
3316 for node_id in &dispatch_path {
3317 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3318 for DispatchActionListener {
3319 action_type,
3320 listener,
3321 } in node.action_listeners.clone()
3322 {
3323 let any_action = action.as_any();
3324 if action_type == any_action.type_id() {
3325 listener(any_action, DispatchPhase::Capture, self);
3326
3327 if !self.propagate_event {
3328 return;
3329 }
3330 }
3331 }
3332 }
3333
3334 // Bubble phase for window actions.
3335 for node_id in dispatch_path.iter().rev() {
3336 let node = self.window.rendered_frame.dispatch_tree.node(*node_id);
3337 for DispatchActionListener {
3338 action_type,
3339 listener,
3340 } in node.action_listeners.clone()
3341 {
3342 let any_action = action.as_any();
3343 if action_type == any_action.type_id() {
3344 self.propagate_event = false; // Actions stop propagation by default during the bubble phase
3345 listener(any_action, DispatchPhase::Bubble, self);
3346
3347 if !self.propagate_event {
3348 return;
3349 }
3350 }
3351 }
3352 }
3353
3354 // Bubble phase for global actions.
3355 if let Some(mut global_listeners) = self
3356 .global_action_listeners
3357 .remove(&action.as_any().type_id())
3358 {
3359 for listener in global_listeners.iter().rev() {
3360 self.propagate_event = false; // Actions stop propagation by default during the bubble phase
3361
3362 listener(action.as_any(), DispatchPhase::Bubble, self);
3363 if !self.propagate_event {
3364 break;
3365 }
3366 }
3367
3368 global_listeners.extend(
3369 self.global_action_listeners
3370 .remove(&action.as_any().type_id())
3371 .unwrap_or_default(),
3372 );
3373
3374 self.global_action_listeners
3375 .insert(action.as_any().type_id(), global_listeners);
3376 }
3377 }
3378
3379 /// Register the given handler to be invoked whenever the global of the given type
3380 /// is updated.
3381 pub fn observe_global<G: Global>(
3382 &mut self,
3383 f: impl Fn(&mut WindowContext<'_>) + 'static,
3384 ) -> Subscription {
3385 let window_handle = self.window.handle;
3386 let (subscription, activate) = self.global_observers.insert(
3387 TypeId::of::<G>(),
3388 Box::new(move |cx| window_handle.update(cx, |_, cx| f(cx)).is_ok()),
3389 );
3390 self.app.defer(move |_| activate());
3391 subscription
3392 }
3393
3394 /// Focus the current window and bring it to the foreground at the platform level.
3395 pub fn activate_window(&self) {
3396 self.window.platform_window.activate();
3397 }
3398
3399 /// Minimize the current window at the platform level.
3400 pub fn minimize_window(&self) {
3401 self.window.platform_window.minimize();
3402 }
3403
3404 /// Toggle full screen status on the current window at the platform level.
3405 pub fn toggle_fullscreen(&self) {
3406 self.window.platform_window.toggle_fullscreen();
3407 }
3408
3409 /// Present a platform dialog.
3410 /// The provided message will be presented, along with buttons for each answer.
3411 /// When a button is clicked, the returned Receiver will receive the index of the clicked button.
3412 pub fn prompt(
3413 &mut self,
3414 level: PromptLevel,
3415 message: &str,
3416 detail: Option<&str>,
3417 answers: &[&str],
3418 ) -> oneshot::Receiver<usize> {
3419 let prompt_builder = self.app.prompt_builder.take();
3420 let Some(prompt_builder) = prompt_builder else {
3421 unreachable!("Re-entrant window prompting is not supported by GPUI");
3422 };
3423
3424 let receiver = match &prompt_builder {
3425 PromptBuilder::Default => self
3426 .window
3427 .platform_window
3428 .prompt(level, message, detail, answers)
3429 .unwrap_or_else(|| {
3430 self.build_custom_prompt(&prompt_builder, level, message, detail, answers)
3431 }),
3432 PromptBuilder::Custom(_) => {
3433 self.build_custom_prompt(&prompt_builder, level, message, detail, answers)
3434 }
3435 };
3436
3437 self.app.prompt_builder = Some(prompt_builder);
3438
3439 receiver
3440 }
3441
3442 fn build_custom_prompt(
3443 &mut self,
3444 prompt_builder: &PromptBuilder,
3445 level: PromptLevel,
3446 message: &str,
3447 detail: Option<&str>,
3448 answers: &[&str],
3449 ) -> oneshot::Receiver<usize> {
3450 let (sender, receiver) = oneshot::channel();
3451 let handle = PromptHandle::new(sender);
3452 let handle = (prompt_builder)(level, message, detail, answers, handle, self);
3453 self.window.prompt = Some(handle);
3454 receiver
3455 }
3456
3457 /// Returns all available actions for the focused element.
3458 pub fn available_actions(&self) -> Vec<Box<dyn Action>> {
3459 let node_id = self
3460 .window
3461 .focus
3462 .and_then(|focus_id| {
3463 self.window
3464 .rendered_frame
3465 .dispatch_tree
3466 .focusable_node_id(focus_id)
3467 })
3468 .unwrap_or_else(|| self.window.rendered_frame.dispatch_tree.root_node_id());
3469
3470 let mut actions = self
3471 .window
3472 .rendered_frame
3473 .dispatch_tree
3474 .available_actions(node_id);
3475 for action_type in self.global_action_listeners.keys() {
3476 if let Err(ix) = actions.binary_search_by_key(action_type, |a| a.as_any().type_id()) {
3477 let action = self.actions.build_action_type(action_type).ok();
3478 if let Some(action) = action {
3479 actions.insert(ix, action);
3480 }
3481 }
3482 }
3483 actions
3484 }
3485
3486 /// Returns key bindings that invoke the given action on the currently focused element.
3487 pub fn bindings_for_action(&self, action: &dyn Action) -> Vec<KeyBinding> {
3488 self.window
3489 .rendered_frame
3490 .dispatch_tree
3491 .bindings_for_action(
3492 action,
3493 &self.window.rendered_frame.dispatch_tree.context_stack,
3494 )
3495 }
3496
3497 /// Returns any bindings that would invoke the given action on the given focus handle if it were focused.
3498 pub fn bindings_for_action_in(
3499 &self,
3500 action: &dyn Action,
3501 focus_handle: &FocusHandle,
3502 ) -> Vec<KeyBinding> {
3503 let dispatch_tree = &self.window.rendered_frame.dispatch_tree;
3504
3505 let Some(node_id) = dispatch_tree.focusable_node_id(focus_handle.id) else {
3506 return vec![];
3507 };
3508 let context_stack: Vec<_> = dispatch_tree
3509 .dispatch_path(node_id)
3510 .into_iter()
3511 .filter_map(|node_id| dispatch_tree.node(node_id).context.clone())
3512 .collect();
3513 dispatch_tree.bindings_for_action(action, &context_stack)
3514 }
3515
3516 /// Returns a generic event listener that invokes the given listener with the view and context associated with the given view handle.
3517 pub fn listener_for<V: Render, E>(
3518 &self,
3519 view: &View<V>,
3520 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
3521 ) -> impl Fn(&E, &mut WindowContext) + 'static {
3522 let view = view.downgrade();
3523 move |e: &E, cx: &mut WindowContext| {
3524 view.update(cx, |view, cx| f(view, e, cx)).ok();
3525 }
3526 }
3527
3528 /// Returns a generic handler that invokes the given handler with the view and context associated with the given view handle.
3529 pub fn handler_for<V: Render>(
3530 &self,
3531 view: &View<V>,
3532 f: impl Fn(&mut V, &mut ViewContext<V>) + 'static,
3533 ) -> impl Fn(&mut WindowContext) {
3534 let view = view.downgrade();
3535 move |cx: &mut WindowContext| {
3536 view.update(cx, |view, cx| f(view, cx)).ok();
3537 }
3538 }
3539
3540 /// Register a callback that can interrupt the closing of the current window based the returned boolean.
3541 /// If the callback returns false, the window won't be closed.
3542 pub fn on_window_should_close(&mut self, f: impl Fn(&mut WindowContext) -> bool + 'static) {
3543 let mut this = self.to_async();
3544 self.window
3545 .platform_window
3546 .on_should_close(Box::new(move || this.update(|cx| f(cx)).unwrap_or(true)))
3547 }
3548
3549 /// Register an action listener on the window for the next frame. The type of action
3550 /// is determined by the first parameter of the given listener. When the next frame is rendered
3551 /// the listener will be cleared.
3552 ///
3553 /// This is a fairly low-level method, so prefer using action handlers on elements unless you have
3554 /// a specific need to register a global listener.
3555 pub fn on_action(
3556 &mut self,
3557 action_type: TypeId,
3558 listener: impl Fn(&dyn Any, DispatchPhase, &mut WindowContext) + 'static,
3559 ) {
3560 self.window
3561 .next_frame
3562 .dispatch_tree
3563 .on_action(action_type, Rc::new(listener));
3564 }
3565}
3566
3567#[cfg(target_os = "windows")]
3568impl WindowContext<'_> {
3569 /// Returns the raw HWND handle for the window.
3570 pub fn get_raw_handle(&self) -> windows::Win32::Foundation::HWND {
3571 self.window.platform_window.get_raw_handle()
3572 }
3573}
3574
3575impl Context for WindowContext<'_> {
3576 type Result<T> = T;
3577
3578 fn new_model<T>(&mut self, build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T) -> Model<T>
3579 where
3580 T: 'static,
3581 {
3582 let slot = self.app.entities.reserve();
3583 let model = build_model(&mut ModelContext::new(&mut *self.app, slot.downgrade()));
3584 self.entities.insert(slot, model)
3585 }
3586
3587 fn reserve_model<T: 'static>(&mut self) -> Self::Result<crate::Reservation<T>> {
3588 self.app.reserve_model()
3589 }
3590
3591 fn insert_model<T: 'static>(
3592 &mut self,
3593 reservation: crate::Reservation<T>,
3594 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
3595 ) -> Self::Result<Model<T>> {
3596 self.app.insert_model(reservation, build_model)
3597 }
3598
3599 fn update_model<T: 'static, R>(
3600 &mut self,
3601 model: &Model<T>,
3602 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
3603 ) -> R {
3604 let mut entity = self.entities.lease(model);
3605 let result = update(
3606 &mut *entity,
3607 &mut ModelContext::new(&mut *self.app, model.downgrade()),
3608 );
3609 self.entities.end_lease(entity);
3610 result
3611 }
3612
3613 fn read_model<T, R>(
3614 &self,
3615 handle: &Model<T>,
3616 read: impl FnOnce(&T, &AppContext) -> R,
3617 ) -> Self::Result<R>
3618 where
3619 T: 'static,
3620 {
3621 let entity = self.entities.read(handle);
3622 read(entity, &*self.app)
3623 }
3624
3625 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
3626 where
3627 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
3628 {
3629 if window == self.window.handle {
3630 let root_view = self.window.root_view.clone().unwrap();
3631 Ok(update(root_view, self))
3632 } else {
3633 window.update(self.app, update)
3634 }
3635 }
3636
3637 fn read_window<T, R>(
3638 &self,
3639 window: &WindowHandle<T>,
3640 read: impl FnOnce(View<T>, &AppContext) -> R,
3641 ) -> Result<R>
3642 where
3643 T: 'static,
3644 {
3645 if window.any_handle == self.window.handle {
3646 let root_view = self
3647 .window
3648 .root_view
3649 .clone()
3650 .unwrap()
3651 .downcast::<T>()
3652 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
3653 Ok(read(root_view, self))
3654 } else {
3655 self.app.read_window(window, read)
3656 }
3657 }
3658}
3659
3660impl VisualContext for WindowContext<'_> {
3661 fn new_view<V>(
3662 &mut self,
3663 build_view_state: impl FnOnce(&mut ViewContext<'_, V>) -> V,
3664 ) -> Self::Result<View<V>>
3665 where
3666 V: 'static + Render,
3667 {
3668 let slot = self.app.entities.reserve();
3669 let view = View {
3670 model: slot.clone(),
3671 };
3672 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, &view);
3673 let entity = build_view_state(&mut cx);
3674 cx.entities.insert(slot, entity);
3675
3676 // Non-generic part to avoid leaking SubscriberSet to invokers of `new_view`.
3677 fn notify_observers(cx: &mut WindowContext, tid: TypeId, view: AnyView) {
3678 cx.new_view_observers.clone().retain(&tid, |observer| {
3679 let any_view = view.clone();
3680 (observer)(any_view, cx);
3681 true
3682 });
3683 }
3684 notify_observers(self, TypeId::of::<V>(), AnyView::from(view.clone()));
3685
3686 view
3687 }
3688
3689 /// Updates the given view. Prefer calling [`View::update`] instead, which calls this method.
3690 fn update_view<T: 'static, R>(
3691 &mut self,
3692 view: &View<T>,
3693 update: impl FnOnce(&mut T, &mut ViewContext<'_, T>) -> R,
3694 ) -> Self::Result<R> {
3695 let mut lease = self.app.entities.lease(&view.model);
3696 let mut cx = ViewContext::new(&mut *self.app, &mut *self.window, view);
3697 let result = update(&mut *lease, &mut cx);
3698 cx.app.entities.end_lease(lease);
3699 result
3700 }
3701
3702 fn replace_root_view<V>(
3703 &mut self,
3704 build_view: impl FnOnce(&mut ViewContext<'_, V>) -> V,
3705 ) -> Self::Result<View<V>>
3706 where
3707 V: 'static + Render,
3708 {
3709 let view = self.new_view(build_view);
3710 self.window.root_view = Some(view.clone().into());
3711 self.refresh();
3712 view
3713 }
3714
3715 fn focus_view<V: crate::FocusableView>(&mut self, view: &View<V>) -> Self::Result<()> {
3716 self.update_view(view, |view, cx| {
3717 view.focus_handle(cx).clone().focus(cx);
3718 })
3719 }
3720
3721 fn dismiss_view<V>(&mut self, view: &View<V>) -> Self::Result<()>
3722 where
3723 V: ManagedView,
3724 {
3725 self.update_view(view, |_, cx| cx.emit(DismissEvent))
3726 }
3727}
3728
3729impl<'a> std::ops::Deref for WindowContext<'a> {
3730 type Target = AppContext;
3731
3732 fn deref(&self) -> &Self::Target {
3733 self.app
3734 }
3735}
3736
3737impl<'a> std::ops::DerefMut for WindowContext<'a> {
3738 fn deref_mut(&mut self) -> &mut Self::Target {
3739 self.app
3740 }
3741}
3742
3743impl<'a> Borrow<AppContext> for WindowContext<'a> {
3744 fn borrow(&self) -> &AppContext {
3745 self.app
3746 }
3747}
3748
3749impl<'a> BorrowMut<AppContext> for WindowContext<'a> {
3750 fn borrow_mut(&mut self) -> &mut AppContext {
3751 self.app
3752 }
3753}
3754
3755/// This trait contains functionality that is shared across [`ViewContext`] and [`WindowContext`]
3756pub trait BorrowWindow: BorrowMut<Window> + BorrowMut<AppContext> {
3757 #[doc(hidden)]
3758 fn app_mut(&mut self) -> &mut AppContext {
3759 self.borrow_mut()
3760 }
3761
3762 #[doc(hidden)]
3763 fn app(&self) -> &AppContext {
3764 self.borrow()
3765 }
3766
3767 #[doc(hidden)]
3768 fn window(&self) -> &Window {
3769 self.borrow()
3770 }
3771
3772 #[doc(hidden)]
3773 fn window_mut(&mut self) -> &mut Window {
3774 self.borrow_mut()
3775 }
3776}
3777
3778impl Borrow<Window> for WindowContext<'_> {
3779 fn borrow(&self) -> &Window {
3780 self.window
3781 }
3782}
3783
3784impl BorrowMut<Window> for WindowContext<'_> {
3785 fn borrow_mut(&mut self) -> &mut Window {
3786 self.window
3787 }
3788}
3789
3790impl<T> BorrowWindow for T where T: BorrowMut<AppContext> + BorrowMut<Window> {}
3791
3792/// Provides access to application state that is specialized for a particular [`View`].
3793/// Allows you to interact with focus, emit events, etc.
3794/// ViewContext also derefs to [`WindowContext`], giving you access to all of its methods as well.
3795/// When you call [`View::update`], you're passed a `&mut V` and an `&mut ViewContext<V>`.
3796pub struct ViewContext<'a, V> {
3797 window_cx: WindowContext<'a>,
3798 view: &'a View<V>,
3799}
3800
3801impl<V> Borrow<AppContext> for ViewContext<'_, V> {
3802 fn borrow(&self) -> &AppContext {
3803 &*self.window_cx.app
3804 }
3805}
3806
3807impl<V> BorrowMut<AppContext> for ViewContext<'_, V> {
3808 fn borrow_mut(&mut self) -> &mut AppContext {
3809 &mut *self.window_cx.app
3810 }
3811}
3812
3813impl<V> Borrow<Window> for ViewContext<'_, V> {
3814 fn borrow(&self) -> &Window {
3815 &*self.window_cx.window
3816 }
3817}
3818
3819impl<V> BorrowMut<Window> for ViewContext<'_, V> {
3820 fn borrow_mut(&mut self) -> &mut Window {
3821 &mut *self.window_cx.window
3822 }
3823}
3824
3825impl<'a, V: 'static> ViewContext<'a, V> {
3826 pub(crate) fn new(app: &'a mut AppContext, window: &'a mut Window, view: &'a View<V>) -> Self {
3827 Self {
3828 window_cx: WindowContext::new(app, window),
3829 view,
3830 }
3831 }
3832
3833 /// Get the entity_id of this view.
3834 pub fn entity_id(&self) -> EntityId {
3835 self.view.entity_id()
3836 }
3837
3838 /// Get the view pointer underlying this context.
3839 pub fn view(&self) -> &View<V> {
3840 self.view
3841 }
3842
3843 /// Get the model underlying this view.
3844 pub fn model(&self) -> &Model<V> {
3845 &self.view.model
3846 }
3847
3848 /// Access the underlying window context.
3849 pub fn window_context(&mut self) -> &mut WindowContext<'a> {
3850 &mut self.window_cx
3851 }
3852
3853 /// Sets a given callback to be run on the next frame.
3854 pub fn on_next_frame(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static)
3855 where
3856 V: 'static,
3857 {
3858 let view = self.view().clone();
3859 self.window_cx.on_next_frame(move |cx| view.update(cx, f));
3860 }
3861
3862 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
3863 /// that are currently on the stack to be returned to the app.
3864 pub fn defer(&mut self, f: impl FnOnce(&mut V, &mut ViewContext<V>) + 'static) {
3865 let view = self.view().downgrade();
3866 self.window_cx.defer(move |cx| {
3867 view.update(cx, f).ok();
3868 });
3869 }
3870
3871 /// Observe another model or view for changes to its state, as tracked by [`ModelContext::notify`].
3872 pub fn observe<V2, E>(
3873 &mut self,
3874 entity: &E,
3875 mut on_notify: impl FnMut(&mut V, E, &mut ViewContext<'_, V>) + 'static,
3876 ) -> Subscription
3877 where
3878 V2: 'static,
3879 V: 'static,
3880 E: Entity<V2>,
3881 {
3882 let view = self.view().downgrade();
3883 let entity_id = entity.entity_id();
3884 let entity = entity.downgrade();
3885 let window_handle = self.window.handle;
3886 self.app.new_observer(
3887 entity_id,
3888 Box::new(move |cx| {
3889 window_handle
3890 .update(cx, |_, cx| {
3891 if let Some(handle) = E::upgrade_from(&entity) {
3892 view.update(cx, |this, cx| on_notify(this, handle, cx))
3893 .is_ok()
3894 } else {
3895 false
3896 }
3897 })
3898 .unwrap_or(false)
3899 }),
3900 )
3901 }
3902
3903 /// Subscribe to events emitted by another model or view.
3904 /// The entity to which you're subscribing must implement the [`EventEmitter`] trait.
3905 /// 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.
3906 pub fn subscribe<V2, E, Evt>(
3907 &mut self,
3908 entity: &E,
3909 mut on_event: impl FnMut(&mut V, E, &Evt, &mut ViewContext<'_, V>) + 'static,
3910 ) -> Subscription
3911 where
3912 V2: EventEmitter<Evt>,
3913 E: Entity<V2>,
3914 Evt: 'static,
3915 {
3916 let view = self.view().downgrade();
3917 let entity_id = entity.entity_id();
3918 let handle = entity.downgrade();
3919 let window_handle = self.window.handle;
3920 self.app.new_subscription(
3921 entity_id,
3922 (
3923 TypeId::of::<Evt>(),
3924 Box::new(move |event, cx| {
3925 window_handle
3926 .update(cx, |_, cx| {
3927 if let Some(handle) = E::upgrade_from(&handle) {
3928 let event = event.downcast_ref().expect("invalid event type");
3929 view.update(cx, |this, cx| on_event(this, handle, event, cx))
3930 .is_ok()
3931 } else {
3932 false
3933 }
3934 })
3935 .unwrap_or(false)
3936 }),
3937 ),
3938 )
3939 }
3940
3941 /// Register a callback to be invoked when the view is released.
3942 ///
3943 /// The callback receives a handle to the view's window. This handle may be
3944 /// invalid, if the window was closed before the view was released.
3945 pub fn on_release(
3946 &mut self,
3947 on_release: impl FnOnce(&mut V, AnyWindowHandle, &mut AppContext) + 'static,
3948 ) -> Subscription {
3949 let window_handle = self.window.handle;
3950 let (subscription, activate) = self.app.release_listeners.insert(
3951 self.view.model.entity_id,
3952 Box::new(move |this, cx| {
3953 let this = this.downcast_mut().expect("invalid entity type");
3954 on_release(this, window_handle, cx)
3955 }),
3956 );
3957 activate();
3958 subscription
3959 }
3960
3961 /// Register a callback to be invoked when the given Model or View is released.
3962 pub fn observe_release<V2, E>(
3963 &mut self,
3964 entity: &E,
3965 mut on_release: impl FnMut(&mut V, &mut V2, &mut ViewContext<'_, V>) + 'static,
3966 ) -> Subscription
3967 where
3968 V: 'static,
3969 V2: 'static,
3970 E: Entity<V2>,
3971 {
3972 let view = self.view().downgrade();
3973 let entity_id = entity.entity_id();
3974 let window_handle = self.window.handle;
3975 let (subscription, activate) = self.app.release_listeners.insert(
3976 entity_id,
3977 Box::new(move |entity, cx| {
3978 let entity = entity.downcast_mut().expect("invalid entity type");
3979 let _ = window_handle.update(cx, |_, cx| {
3980 view.update(cx, |this, cx| on_release(this, entity, cx))
3981 });
3982 }),
3983 );
3984 activate();
3985 subscription
3986 }
3987
3988 /// Indicate that this view has changed, which will invoke any observers and also mark the window as dirty.
3989 /// If this view or any of its ancestors are *cached*, notifying it will cause it or its ancestors to be redrawn.
3990 pub fn notify(&mut self) {
3991 self.window_cx.notify(self.view.entity_id());
3992 }
3993
3994 /// Register a callback to be invoked when the window is resized.
3995 pub fn observe_window_bounds(
3996 &mut self,
3997 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
3998 ) -> Subscription {
3999 let view = self.view.downgrade();
4000 let (subscription, activate) = self.window.bounds_observers.insert(
4001 (),
4002 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
4003 );
4004 activate();
4005 subscription
4006 }
4007
4008 /// Register a callback to be invoked when the window is activated or deactivated.
4009 pub fn observe_window_activation(
4010 &mut self,
4011 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4012 ) -> Subscription {
4013 let view = self.view.downgrade();
4014 let (subscription, activate) = self.window.activation_observers.insert(
4015 (),
4016 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
4017 );
4018 activate();
4019 subscription
4020 }
4021
4022 /// Registers a callback to be invoked when the window appearance changes.
4023 pub fn observe_window_appearance(
4024 &mut self,
4025 mut callback: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4026 ) -> Subscription {
4027 let view = self.view.downgrade();
4028 let (subscription, activate) = self.window.appearance_observers.insert(
4029 (),
4030 Box::new(move |cx| view.update(cx, |view, cx| callback(view, cx)).is_ok()),
4031 );
4032 activate();
4033 subscription
4034 }
4035
4036 /// Register a listener to be called when the given focus handle receives focus.
4037 /// Returns a subscription and persists until the subscription is dropped.
4038 pub fn on_focus(
4039 &mut self,
4040 handle: &FocusHandle,
4041 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4042 ) -> Subscription {
4043 let view = self.view.downgrade();
4044 let focus_id = handle.id;
4045 let (subscription, activate) =
4046 self.window.new_focus_listener(Box::new(move |event, cx| {
4047 view.update(cx, |view, cx| {
4048 if event.previous_focus_path.last() != Some(&focus_id)
4049 && event.current_focus_path.last() == Some(&focus_id)
4050 {
4051 listener(view, cx)
4052 }
4053 })
4054 .is_ok()
4055 }));
4056 self.app.defer(|_| activate());
4057 subscription
4058 }
4059
4060 /// Register a listener to be called when the given focus handle or one of its descendants receives focus.
4061 /// Returns a subscription and persists until the subscription is dropped.
4062 pub fn on_focus_in(
4063 &mut self,
4064 handle: &FocusHandle,
4065 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4066 ) -> Subscription {
4067 let view = self.view.downgrade();
4068 let focus_id = handle.id;
4069 let (subscription, activate) =
4070 self.window.new_focus_listener(Box::new(move |event, cx| {
4071 view.update(cx, |view, cx| {
4072 if !event.previous_focus_path.contains(&focus_id)
4073 && event.current_focus_path.contains(&focus_id)
4074 {
4075 listener(view, cx)
4076 }
4077 })
4078 .is_ok()
4079 }));
4080 self.app.defer(move |_| activate());
4081 subscription
4082 }
4083
4084 /// Register a listener to be called when the given focus handle loses focus.
4085 /// Returns a subscription and persists until the subscription is dropped.
4086 pub fn on_blur(
4087 &mut self,
4088 handle: &FocusHandle,
4089 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4090 ) -> Subscription {
4091 let view = self.view.downgrade();
4092 let focus_id = handle.id;
4093 let (subscription, activate) =
4094 self.window.new_focus_listener(Box::new(move |event, cx| {
4095 view.update(cx, |view, cx| {
4096 if event.previous_focus_path.last() == Some(&focus_id)
4097 && event.current_focus_path.last() != Some(&focus_id)
4098 {
4099 listener(view, cx)
4100 }
4101 })
4102 .is_ok()
4103 }));
4104 self.app.defer(move |_| activate());
4105 subscription
4106 }
4107
4108 /// Register a listener to be called when nothing in the window has focus.
4109 /// This typically happens when the node that was focused is removed from the tree,
4110 /// and this callback lets you chose a default place to restore the users focus.
4111 /// Returns a subscription and persists until the subscription is dropped.
4112 pub fn on_focus_lost(
4113 &mut self,
4114 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4115 ) -> Subscription {
4116 let view = self.view.downgrade();
4117 let (subscription, activate) = self.window.focus_lost_listeners.insert(
4118 (),
4119 Box::new(move |cx| view.update(cx, |view, cx| listener(view, cx)).is_ok()),
4120 );
4121 activate();
4122 subscription
4123 }
4124
4125 /// Register a listener to be called when the given focus handle or one of its descendants loses focus.
4126 /// Returns a subscription and persists until the subscription is dropped.
4127 pub fn on_focus_out(
4128 &mut self,
4129 handle: &FocusHandle,
4130 mut listener: impl FnMut(&mut V, &mut ViewContext<V>) + 'static,
4131 ) -> Subscription {
4132 let view = self.view.downgrade();
4133 let focus_id = handle.id;
4134 let (subscription, activate) =
4135 self.window.new_focus_listener(Box::new(move |event, cx| {
4136 view.update(cx, |view, cx| {
4137 if event.previous_focus_path.contains(&focus_id)
4138 && !event.current_focus_path.contains(&focus_id)
4139 {
4140 listener(view, cx)
4141 }
4142 })
4143 .is_ok()
4144 }));
4145 self.app.defer(move |_| activate());
4146 subscription
4147 }
4148
4149 /// Schedule a future to be run asynchronously.
4150 /// The given callback is invoked with a [`WeakView<V>`] to avoid leaking the view for a long-running process.
4151 /// It's also given an [`AsyncWindowContext`], which can be used to access the state of the view across await points.
4152 /// The returned future will be polled on the main thread.
4153 pub fn spawn<Fut, R>(
4154 &mut self,
4155 f: impl FnOnce(WeakView<V>, AsyncWindowContext) -> Fut,
4156 ) -> Task<R>
4157 where
4158 R: 'static,
4159 Fut: Future<Output = R> + 'static,
4160 {
4161 let view = self.view().downgrade();
4162 self.window_cx.spawn(|cx| f(view, cx))
4163 }
4164
4165 /// Register a callback to be invoked when the given global state changes.
4166 pub fn observe_global<G: Global>(
4167 &mut self,
4168 mut f: impl FnMut(&mut V, &mut ViewContext<'_, V>) + 'static,
4169 ) -> Subscription {
4170 let window_handle = self.window.handle;
4171 let view = self.view().downgrade();
4172 let (subscription, activate) = self.global_observers.insert(
4173 TypeId::of::<G>(),
4174 Box::new(move |cx| {
4175 window_handle
4176 .update(cx, |_, cx| view.update(cx, |view, cx| f(view, cx)).is_ok())
4177 .unwrap_or(false)
4178 }),
4179 );
4180 self.app.defer(move |_| activate());
4181 subscription
4182 }
4183
4184 /// Register a callback to be invoked when the given Action type is dispatched to the window.
4185 pub fn on_action(
4186 &mut self,
4187 action_type: TypeId,
4188 listener: impl Fn(&mut V, &dyn Any, DispatchPhase, &mut ViewContext<V>) + 'static,
4189 ) {
4190 let handle = self.view().clone();
4191 self.window_cx
4192 .on_action(action_type, move |action, phase, cx| {
4193 handle.update(cx, |view, cx| {
4194 listener(view, action, phase, cx);
4195 })
4196 });
4197 }
4198
4199 /// Emit an event to be handled any other views that have subscribed via [ViewContext::subscribe].
4200 pub fn emit<Evt>(&mut self, event: Evt)
4201 where
4202 Evt: 'static,
4203 V: EventEmitter<Evt>,
4204 {
4205 let emitter = self.view.model.entity_id;
4206 self.app.push_effect(Effect::Emit {
4207 emitter,
4208 event_type: TypeId::of::<Evt>(),
4209 event: Box::new(event),
4210 });
4211 }
4212
4213 /// Move focus to the current view, assuming it implements [`FocusableView`].
4214 pub fn focus_self(&mut self)
4215 where
4216 V: FocusableView,
4217 {
4218 self.defer(|view, cx| view.focus_handle(cx).focus(cx))
4219 }
4220
4221 /// Convenience method for accessing view state in an event callback.
4222 ///
4223 /// Many GPUI callbacks take the form of `Fn(&E, &mut WindowContext)`,
4224 /// but it's often useful to be able to access view state in these
4225 /// callbacks. This method provides a convenient way to do so.
4226 pub fn listener<E>(
4227 &self,
4228 f: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
4229 ) -> impl Fn(&E, &mut WindowContext) + 'static {
4230 let view = self.view().downgrade();
4231 move |e: &E, cx: &mut WindowContext| {
4232 view.update(cx, |view, cx| f(view, e, cx)).ok();
4233 }
4234 }
4235}
4236
4237impl<V> Context for ViewContext<'_, V> {
4238 type Result<U> = U;
4239
4240 fn new_model<T: 'static>(
4241 &mut self,
4242 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
4243 ) -> Model<T> {
4244 self.window_cx.new_model(build_model)
4245 }
4246
4247 fn reserve_model<T: 'static>(&mut self) -> Self::Result<crate::Reservation<T>> {
4248 self.window_cx.reserve_model()
4249 }
4250
4251 fn insert_model<T: 'static>(
4252 &mut self,
4253 reservation: crate::Reservation<T>,
4254 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
4255 ) -> Self::Result<Model<T>> {
4256 self.window_cx.insert_model(reservation, build_model)
4257 }
4258
4259 fn update_model<T: 'static, R>(
4260 &mut self,
4261 model: &Model<T>,
4262 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
4263 ) -> R {
4264 self.window_cx.update_model(model, update)
4265 }
4266
4267 fn read_model<T, R>(
4268 &self,
4269 handle: &Model<T>,
4270 read: impl FnOnce(&T, &AppContext) -> R,
4271 ) -> Self::Result<R>
4272 where
4273 T: 'static,
4274 {
4275 self.window_cx.read_model(handle, read)
4276 }
4277
4278 fn update_window<T, F>(&mut self, window: AnyWindowHandle, update: F) -> Result<T>
4279 where
4280 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
4281 {
4282 self.window_cx.update_window(window, update)
4283 }
4284
4285 fn read_window<T, R>(
4286 &self,
4287 window: &WindowHandle<T>,
4288 read: impl FnOnce(View<T>, &AppContext) -> R,
4289 ) -> Result<R>
4290 where
4291 T: 'static,
4292 {
4293 self.window_cx.read_window(window, read)
4294 }
4295}
4296
4297impl<V: 'static> VisualContext for ViewContext<'_, V> {
4298 fn new_view<W: Render + 'static>(
4299 &mut self,
4300 build_view_state: impl FnOnce(&mut ViewContext<'_, W>) -> W,
4301 ) -> Self::Result<View<W>> {
4302 self.window_cx.new_view(build_view_state)
4303 }
4304
4305 fn update_view<V2: 'static, R>(
4306 &mut self,
4307 view: &View<V2>,
4308 update: impl FnOnce(&mut V2, &mut ViewContext<'_, V2>) -> R,
4309 ) -> Self::Result<R> {
4310 self.window_cx.update_view(view, update)
4311 }
4312
4313 fn replace_root_view<W>(
4314 &mut self,
4315 build_view: impl FnOnce(&mut ViewContext<'_, W>) -> W,
4316 ) -> Self::Result<View<W>>
4317 where
4318 W: 'static + Render,
4319 {
4320 self.window_cx.replace_root_view(build_view)
4321 }
4322
4323 fn focus_view<W: FocusableView>(&mut self, view: &View<W>) -> Self::Result<()> {
4324 self.window_cx.focus_view(view)
4325 }
4326
4327 fn dismiss_view<W: ManagedView>(&mut self, view: &View<W>) -> Self::Result<()> {
4328 self.window_cx.dismiss_view(view)
4329 }
4330}
4331
4332impl<'a, V> std::ops::Deref for ViewContext<'a, V> {
4333 type Target = WindowContext<'a>;
4334
4335 fn deref(&self) -> &Self::Target {
4336 &self.window_cx
4337 }
4338}
4339
4340impl<'a, V> std::ops::DerefMut for ViewContext<'a, V> {
4341 fn deref_mut(&mut self) -> &mut Self::Target {
4342 &mut self.window_cx
4343 }
4344}
4345
4346// #[derive(Clone, Copy, Eq, PartialEq, Hash)]
4347slotmap::new_key_type! {
4348 /// A unique identifier for a window.
4349 pub struct WindowId;
4350}
4351
4352impl WindowId {
4353 /// Converts this window ID to a `u64`.
4354 pub fn as_u64(&self) -> u64 {
4355 self.0.as_ffi()
4356 }
4357}
4358
4359/// A handle to a window with a specific root view type.
4360/// Note that this does not keep the window alive on its own.
4361#[derive(Deref, DerefMut)]
4362pub struct WindowHandle<V> {
4363 #[deref]
4364 #[deref_mut]
4365 pub(crate) any_handle: AnyWindowHandle,
4366 state_type: PhantomData<V>,
4367}
4368
4369impl<V: 'static + Render> WindowHandle<V> {
4370 /// Creates a new handle from a window ID.
4371 /// This does not check if the root type of the window is `V`.
4372 pub fn new(id: WindowId) -> Self {
4373 WindowHandle {
4374 any_handle: AnyWindowHandle {
4375 id,
4376 state_type: TypeId::of::<V>(),
4377 },
4378 state_type: PhantomData,
4379 }
4380 }
4381
4382 /// Get the root view out of this window.
4383 ///
4384 /// This will fail if the window is closed or if the root view's type does not match `V`.
4385 pub fn root<C>(&self, cx: &mut C) -> Result<View<V>>
4386 where
4387 C: Context,
4388 {
4389 Flatten::flatten(cx.update_window(self.any_handle, |root_view, _| {
4390 root_view
4391 .downcast::<V>()
4392 .map_err(|_| anyhow!("the type of the window's root view has changed"))
4393 }))
4394 }
4395
4396 /// Updates the root view of this window.
4397 ///
4398 /// This will fail if the window has been closed or if the root view's type does not match
4399 pub fn update<C, R>(
4400 &self,
4401 cx: &mut C,
4402 update: impl FnOnce(&mut V, &mut ViewContext<'_, V>) -> R,
4403 ) -> Result<R>
4404 where
4405 C: Context,
4406 {
4407 cx.update_window(self.any_handle, |root_view, cx| {
4408 let view = root_view
4409 .downcast::<V>()
4410 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
4411 Ok(cx.update_view(&view, update))
4412 })?
4413 }
4414
4415 /// Read the root view out of this window.
4416 ///
4417 /// This will fail if the window is closed or if the root view's type does not match `V`.
4418 pub fn read<'a>(&self, cx: &'a AppContext) -> Result<&'a V> {
4419 let x = cx
4420 .windows
4421 .get(self.id)
4422 .and_then(|window| {
4423 window
4424 .as_ref()
4425 .and_then(|window| window.root_view.clone())
4426 .map(|root_view| root_view.downcast::<V>())
4427 })
4428 .ok_or_else(|| anyhow!("window not found"))?
4429 .map_err(|_| anyhow!("the type of the window's root view has changed"))?;
4430
4431 Ok(x.read(cx))
4432 }
4433
4434 /// Read the root view out of this window, with a callback
4435 ///
4436 /// This will fail if the window is closed or if the root view's type does not match `V`.
4437 pub fn read_with<C, R>(&self, cx: &C, read_with: impl FnOnce(&V, &AppContext) -> R) -> Result<R>
4438 where
4439 C: Context,
4440 {
4441 cx.read_window(self, |root_view, cx| read_with(root_view.read(cx), cx))
4442 }
4443
4444 /// Read the root view pointer off of this window.
4445 ///
4446 /// This will fail if the window is closed or if the root view's type does not match `V`.
4447 pub fn root_view<C>(&self, cx: &C) -> Result<View<V>>
4448 where
4449 C: Context,
4450 {
4451 cx.read_window(self, |root_view, _cx| root_view.clone())
4452 }
4453
4454 /// Check if this window is 'active'.
4455 ///
4456 /// Will return `None` if the window is closed or currently
4457 /// borrowed.
4458 pub fn is_active(&self, cx: &mut AppContext) -> Option<bool> {
4459 cx.update_window(self.any_handle, |_, cx| cx.is_window_active())
4460 .ok()
4461 }
4462}
4463
4464impl<V> Copy for WindowHandle<V> {}
4465
4466impl<V> Clone for WindowHandle<V> {
4467 fn clone(&self) -> Self {
4468 *self
4469 }
4470}
4471
4472impl<V> PartialEq for WindowHandle<V> {
4473 fn eq(&self, other: &Self) -> bool {
4474 self.any_handle == other.any_handle
4475 }
4476}
4477
4478impl<V> Eq for WindowHandle<V> {}
4479
4480impl<V> Hash for WindowHandle<V> {
4481 fn hash<H: Hasher>(&self, state: &mut H) {
4482 self.any_handle.hash(state);
4483 }
4484}
4485
4486impl<V: 'static> From<WindowHandle<V>> for AnyWindowHandle {
4487 fn from(val: WindowHandle<V>) -> Self {
4488 val.any_handle
4489 }
4490}
4491
4492unsafe impl<V> Send for WindowHandle<V> {}
4493unsafe impl<V> Sync for WindowHandle<V> {}
4494
4495/// A handle to a window with any root view type, which can be downcast to a window with a specific root view type.
4496#[derive(Copy, Clone, PartialEq, Eq, Hash)]
4497pub struct AnyWindowHandle {
4498 pub(crate) id: WindowId,
4499 state_type: TypeId,
4500}
4501
4502impl AnyWindowHandle {
4503 /// Get the ID of this window.
4504 pub fn window_id(&self) -> WindowId {
4505 self.id
4506 }
4507
4508 /// Attempt to convert this handle to a window handle with a specific root view type.
4509 /// If the types do not match, this will return `None`.
4510 pub fn downcast<T: 'static>(&self) -> Option<WindowHandle<T>> {
4511 if TypeId::of::<T>() == self.state_type {
4512 Some(WindowHandle {
4513 any_handle: *self,
4514 state_type: PhantomData,
4515 })
4516 } else {
4517 None
4518 }
4519 }
4520
4521 /// Updates the state of the root view of this window.
4522 ///
4523 /// This will fail if the window has been closed.
4524 pub fn update<C, R>(
4525 self,
4526 cx: &mut C,
4527 update: impl FnOnce(AnyView, &mut WindowContext<'_>) -> R,
4528 ) -> Result<R>
4529 where
4530 C: Context,
4531 {
4532 cx.update_window(self, update)
4533 }
4534
4535 /// Read the state of the root view of this window.
4536 ///
4537 /// This will fail if the window has been closed.
4538 pub fn read<T, C, R>(self, cx: &C, read: impl FnOnce(View<T>, &AppContext) -> R) -> Result<R>
4539 where
4540 C: Context,
4541 T: 'static,
4542 {
4543 let view = self
4544 .downcast::<T>()
4545 .context("the type of the window's root view has changed")?;
4546
4547 cx.read_window(&view, read)
4548 }
4549}
4550
4551/// An identifier for an [`Element`](crate::Element).
4552///
4553/// Can be constructed with a string, a number, or both, as well
4554/// as other internal representations.
4555#[derive(Clone, Debug, Eq, PartialEq, Hash)]
4556pub enum ElementId {
4557 /// The ID of a View element
4558 View(EntityId),
4559 /// An integer ID.
4560 Integer(usize),
4561 /// A string based ID.
4562 Name(SharedString),
4563 /// A UUID.
4564 Uuid(Uuid),
4565 /// An ID that's equated with a focus handle.
4566 FocusHandle(FocusId),
4567 /// A combination of a name and an integer.
4568 NamedInteger(SharedString, usize),
4569}
4570
4571impl Display for ElementId {
4572 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
4573 match self {
4574 ElementId::View(entity_id) => write!(f, "view-{}", entity_id)?,
4575 ElementId::Integer(ix) => write!(f, "{}", ix)?,
4576 ElementId::Name(name) => write!(f, "{}", name)?,
4577 ElementId::FocusHandle(_) => write!(f, "FocusHandle")?,
4578 ElementId::NamedInteger(s, i) => write!(f, "{}-{}", s, i)?,
4579 ElementId::Uuid(uuid) => write!(f, "{}", uuid)?,
4580 }
4581
4582 Ok(())
4583 }
4584}
4585
4586impl TryInto<SharedString> for ElementId {
4587 type Error = anyhow::Error;
4588
4589 fn try_into(self) -> anyhow::Result<SharedString> {
4590 if let ElementId::Name(name) = self {
4591 Ok(name)
4592 } else {
4593 Err(anyhow!("element id is not string"))
4594 }
4595 }
4596}
4597
4598impl From<usize> for ElementId {
4599 fn from(id: usize) -> Self {
4600 ElementId::Integer(id)
4601 }
4602}
4603
4604impl From<i32> for ElementId {
4605 fn from(id: i32) -> Self {
4606 Self::Integer(id as usize)
4607 }
4608}
4609
4610impl From<SharedString> for ElementId {
4611 fn from(name: SharedString) -> Self {
4612 ElementId::Name(name)
4613 }
4614}
4615
4616impl From<&'static str> for ElementId {
4617 fn from(name: &'static str) -> Self {
4618 ElementId::Name(name.into())
4619 }
4620}
4621
4622impl<'a> From<&'a FocusHandle> for ElementId {
4623 fn from(handle: &'a FocusHandle) -> Self {
4624 ElementId::FocusHandle(handle.id)
4625 }
4626}
4627
4628impl From<(&'static str, EntityId)> for ElementId {
4629 fn from((name, id): (&'static str, EntityId)) -> Self {
4630 ElementId::NamedInteger(name.into(), id.as_u64() as usize)
4631 }
4632}
4633
4634impl From<(&'static str, usize)> for ElementId {
4635 fn from((name, id): (&'static str, usize)) -> Self {
4636 ElementId::NamedInteger(name.into(), id)
4637 }
4638}
4639
4640impl From<(&'static str, u64)> for ElementId {
4641 fn from((name, id): (&'static str, u64)) -> Self {
4642 ElementId::NamedInteger(name.into(), id as usize)
4643 }
4644}
4645
4646impl From<Uuid> for ElementId {
4647 fn from(value: Uuid) -> Self {
4648 Self::Uuid(value)
4649 }
4650}
4651
4652impl From<(&'static str, u32)> for ElementId {
4653 fn from((name, id): (&'static str, u32)) -> Self {
4654 ElementId::NamedInteger(name.into(), id as usize)
4655 }
4656}
4657
4658/// A rectangle to be rendered in the window at the given position and size.
4659/// Passed as an argument [`WindowContext::paint_quad`].
4660#[derive(Clone)]
4661pub struct PaintQuad {
4662 /// The bounds of the quad within the window.
4663 pub bounds: Bounds<Pixels>,
4664 /// The radii of the quad's corners.
4665 pub corner_radii: Corners<Pixels>,
4666 /// The background color of the quad.
4667 pub background: Hsla,
4668 /// The widths of the quad's borders.
4669 pub border_widths: Edges<Pixels>,
4670 /// The color of the quad's borders.
4671 pub border_color: Hsla,
4672}
4673
4674impl PaintQuad {
4675 /// Sets the corner radii of the quad.
4676 pub fn corner_radii(self, corner_radii: impl Into<Corners<Pixels>>) -> Self {
4677 PaintQuad {
4678 corner_radii: corner_radii.into(),
4679 ..self
4680 }
4681 }
4682
4683 /// Sets the border widths of the quad.
4684 pub fn border_widths(self, border_widths: impl Into<Edges<Pixels>>) -> Self {
4685 PaintQuad {
4686 border_widths: border_widths.into(),
4687 ..self
4688 }
4689 }
4690
4691 /// Sets the border color of the quad.
4692 pub fn border_color(self, border_color: impl Into<Hsla>) -> Self {
4693 PaintQuad {
4694 border_color: border_color.into(),
4695 ..self
4696 }
4697 }
4698
4699 /// Sets the background color of the quad.
4700 pub fn background(self, background: impl Into<Hsla>) -> Self {
4701 PaintQuad {
4702 background: background.into(),
4703 ..self
4704 }
4705 }
4706}
4707
4708/// Creates a quad with the given parameters.
4709pub fn quad(
4710 bounds: Bounds<Pixels>,
4711 corner_radii: impl Into<Corners<Pixels>>,
4712 background: impl Into<Hsla>,
4713 border_widths: impl Into<Edges<Pixels>>,
4714 border_color: impl Into<Hsla>,
4715) -> PaintQuad {
4716 PaintQuad {
4717 bounds,
4718 corner_radii: corner_radii.into(),
4719 background: background.into(),
4720 border_widths: border_widths.into(),
4721 border_color: border_color.into(),
4722 }
4723}
4724
4725/// Creates a filled quad with the given bounds and background color.
4726pub fn fill(bounds: impl Into<Bounds<Pixels>>, background: impl Into<Hsla>) -> PaintQuad {
4727 PaintQuad {
4728 bounds: bounds.into(),
4729 corner_radii: (0.).into(),
4730 background: background.into(),
4731 border_widths: (0.).into(),
4732 border_color: transparent_black(),
4733 }
4734}
4735
4736/// Creates a rectangle outline with the given bounds, border color, and a 1px border width
4737pub fn outline(bounds: impl Into<Bounds<Pixels>>, border_color: impl Into<Hsla>) -> PaintQuad {
4738 PaintQuad {
4739 bounds: bounds.into(),
4740 corner_radii: (0.).into(),
4741 background: transparent_black(),
4742 border_widths: (1.).into(),
4743 border_color: border_color.into(),
4744 }
4745}