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