1use crate::{
2 elements::ElementBox,
3 executor::{self, Task},
4 keymap::{self, Keystroke},
5 platform::{self, CursorStyle, Platform, PromptLevel, WindowOptions},
6 presenter::Presenter,
7 util::post_inc,
8 AssetCache, AssetSource, ClipboardItem, FontCache, PathPromptOptions, TextLayoutCache,
9};
10use anyhow::{anyhow, Result};
11use collections::btree_map;
12use keymap::MatchResult;
13use lazy_static::lazy_static;
14use parking_lot::Mutex;
15use platform::Event;
16use postage::oneshot;
17use smol::prelude::*;
18use std::{
19 any::{type_name, Any, TypeId},
20 cell::RefCell,
21 collections::{hash_map::Entry, BTreeMap, HashMap, HashSet, VecDeque},
22 fmt::{self, Debug},
23 hash::{Hash, Hasher},
24 marker::PhantomData,
25 mem,
26 ops::{Deref, DerefMut},
27 path::{Path, PathBuf},
28 pin::Pin,
29 rc::{self, Rc},
30 sync::{
31 atomic::{AtomicUsize, Ordering::SeqCst},
32 Arc, Weak,
33 },
34 time::Duration,
35};
36
37pub trait Entity: 'static {
38 type Event;
39
40 fn release(&mut self, _: &mut MutableAppContext) {}
41 fn app_will_quit(
42 &mut self,
43 _: &mut MutableAppContext,
44 ) -> Option<Pin<Box<dyn 'static + Future<Output = ()>>>> {
45 None
46 }
47}
48
49pub trait View: Entity + Sized {
50 fn ui_name() -> &'static str;
51 fn render(&mut self, cx: &mut RenderContext<'_, Self>) -> ElementBox;
52 fn on_focus(&mut self, _: &mut ViewContext<Self>) {}
53 fn on_blur(&mut self, _: &mut ViewContext<Self>) {}
54 fn keymap_context(&self, _: &AppContext) -> keymap::Context {
55 Self::default_keymap_context()
56 }
57 fn default_keymap_context() -> keymap::Context {
58 let mut cx = keymap::Context::default();
59 cx.set.insert(Self::ui_name().into());
60 cx
61 }
62}
63
64pub trait ReadModel {
65 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T;
66}
67
68pub trait ReadModelWith {
69 fn read_model_with<E: Entity, T>(
70 &self,
71 handle: &ModelHandle<E>,
72 read: &mut dyn FnMut(&E, &AppContext) -> T,
73 ) -> T;
74}
75
76pub trait UpdateModel {
77 fn update_model<T: Entity, O>(
78 &mut self,
79 handle: &ModelHandle<T>,
80 update: &mut dyn FnMut(&mut T, &mut ModelContext<T>) -> O,
81 ) -> O;
82}
83
84pub trait UpgradeModelHandle {
85 fn upgrade_model_handle<T: Entity>(
86 &self,
87 handle: &WeakModelHandle<T>,
88 ) -> Option<ModelHandle<T>>;
89
90 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool;
91
92 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle>;
93}
94
95pub trait UpgradeViewHandle {
96 fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>>;
97
98 fn upgrade_any_view_handle(&self, handle: &AnyWeakViewHandle) -> Option<AnyViewHandle>;
99}
100
101pub trait ReadView {
102 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T;
103}
104
105pub trait ReadViewWith {
106 fn read_view_with<V, T>(
107 &self,
108 handle: &ViewHandle<V>,
109 read: &mut dyn FnMut(&V, &AppContext) -> T,
110 ) -> T
111 where
112 V: View;
113}
114
115pub trait UpdateView {
116 fn update_view<T, S>(
117 &mut self,
118 handle: &ViewHandle<T>,
119 update: &mut dyn FnMut(&mut T, &mut ViewContext<T>) -> S,
120 ) -> S
121 where
122 T: View;
123}
124
125pub trait ElementStateContext: DerefMut<Target = MutableAppContext> {
126 fn current_view_id(&self) -> usize;
127
128 fn element_state<Tag: 'static, T: 'static + Default>(
129 &mut self,
130 element_id: usize,
131 ) -> ElementStateHandle<T> {
132 let id = ElementStateId {
133 view_id: self.current_view_id(),
134 element_id,
135 tag: TypeId::of::<Tag>(),
136 };
137 self.cx
138 .element_states
139 .entry(id)
140 .or_insert_with(|| Box::new(T::default()));
141 ElementStateHandle::new(id, self.frame_count, &self.cx.ref_counts)
142 }
143}
144
145pub trait Action: 'static + AnyAction {
146 type Argument: 'static + Clone;
147}
148
149pub trait AnyAction {
150 fn id(&self) -> TypeId;
151 fn name(&self) -> &'static str;
152 fn as_any(&self) -> &dyn Any;
153 fn boxed_clone(&self) -> Box<dyn AnyAction>;
154 fn boxed_clone_as_any(&self) -> Box<dyn Any>;
155}
156
157#[macro_export]
158macro_rules! action {
159 ($name:ident, $arg:ty) => {
160 #[derive(Clone)]
161 pub struct $name(pub $arg);
162
163 impl $crate::Action for $name {
164 type Argument = $arg;
165 }
166
167 impl $crate::AnyAction for $name {
168 fn id(&self) -> std::any::TypeId {
169 std::any::TypeId::of::<$name>()
170 }
171
172 fn name(&self) -> &'static str {
173 stringify!($name)
174 }
175
176 fn as_any(&self) -> &dyn std::any::Any {
177 self
178 }
179
180 fn boxed_clone(&self) -> Box<dyn $crate::AnyAction> {
181 Box::new(self.clone())
182 }
183
184 fn boxed_clone_as_any(&self) -> Box<dyn std::any::Any> {
185 Box::new(self.clone())
186 }
187 }
188
189 impl From<$arg> for $name {
190 fn from(arg: $arg) -> Self {
191 Self(arg)
192 }
193 }
194 };
195
196 ($name:ident) => {
197 #[derive(Clone, Debug, Eq, PartialEq)]
198 pub struct $name;
199
200 impl $crate::Action for $name {
201 type Argument = ();
202 }
203
204 impl $crate::AnyAction for $name {
205 fn id(&self) -> std::any::TypeId {
206 std::any::TypeId::of::<$name>()
207 }
208
209 fn name(&self) -> &'static str {
210 stringify!($name)
211 }
212
213 fn as_any(&self) -> &dyn std::any::Any {
214 self
215 }
216
217 fn boxed_clone(&self) -> Box<dyn $crate::AnyAction> {
218 Box::new(self.clone())
219 }
220
221 fn boxed_clone_as_any(&self) -> Box<dyn std::any::Any> {
222 Box::new(self.clone())
223 }
224 }
225 };
226}
227
228pub struct Menu<'a> {
229 pub name: &'a str,
230 pub items: Vec<MenuItem<'a>>,
231}
232
233pub enum MenuItem<'a> {
234 Action {
235 name: &'a str,
236 keystroke: Option<&'a str>,
237 action: Box<dyn AnyAction>,
238 },
239 Separator,
240}
241
242#[derive(Clone)]
243pub struct App(Rc<RefCell<MutableAppContext>>);
244
245#[derive(Clone)]
246pub struct AsyncAppContext(Rc<RefCell<MutableAppContext>>);
247
248#[cfg(any(test, feature = "test-support"))]
249pub struct TestAppContext {
250 cx: Rc<RefCell<MutableAppContext>>,
251 foreground_platform: Rc<platform::test::ForegroundPlatform>,
252}
253
254impl App {
255 pub fn new(asset_source: impl AssetSource) -> Result<Self> {
256 let platform = platform::current::platform();
257 let foreground_platform = platform::current::foreground_platform();
258 let foreground = Rc::new(executor::Foreground::platform(platform.dispatcher())?);
259 let app = Self(Rc::new(RefCell::new(MutableAppContext::new(
260 foreground,
261 Arc::new(executor::Background::new()),
262 platform.clone(),
263 foreground_platform.clone(),
264 Arc::new(FontCache::new(platform.fonts())),
265 Default::default(),
266 asset_source,
267 ))));
268
269 foreground_platform.on_quit(Box::new({
270 let cx = app.0.clone();
271 move || {
272 cx.borrow_mut().quit();
273 }
274 }));
275 foreground_platform.on_menu_command(Box::new({
276 let cx = app.0.clone();
277 move |action| {
278 let mut cx = cx.borrow_mut();
279 if let Some(key_window_id) = cx.cx.platform.key_window_id() {
280 if let Some((presenter, _)) =
281 cx.presenters_and_platform_windows.get(&key_window_id)
282 {
283 let presenter = presenter.clone();
284 let path = presenter.borrow().dispatch_path(cx.as_ref());
285 cx.dispatch_action_any(key_window_id, &path, action);
286 } else {
287 cx.dispatch_global_action_any(action);
288 }
289 } else {
290 cx.dispatch_global_action_any(action);
291 }
292 }
293 }));
294
295 app.0.borrow_mut().weak_self = Some(Rc::downgrade(&app.0));
296 Ok(app)
297 }
298
299 pub fn background(&self) -> Arc<executor::Background> {
300 self.0.borrow().background().clone()
301 }
302
303 pub fn on_become_active<F>(self, mut callback: F) -> Self
304 where
305 F: 'static + FnMut(&mut MutableAppContext),
306 {
307 let cx = self.0.clone();
308 self.0
309 .borrow_mut()
310 .foreground_platform
311 .on_become_active(Box::new(move || callback(&mut *cx.borrow_mut())));
312 self
313 }
314
315 pub fn on_resign_active<F>(self, mut callback: F) -> Self
316 where
317 F: 'static + FnMut(&mut MutableAppContext),
318 {
319 let cx = self.0.clone();
320 self.0
321 .borrow_mut()
322 .foreground_platform
323 .on_resign_active(Box::new(move || callback(&mut *cx.borrow_mut())));
324 self
325 }
326
327 pub fn on_quit<F>(self, mut callback: F) -> Self
328 where
329 F: 'static + FnMut(&mut MutableAppContext),
330 {
331 let cx = self.0.clone();
332 self.0
333 .borrow_mut()
334 .foreground_platform
335 .on_quit(Box::new(move || callback(&mut *cx.borrow_mut())));
336 self
337 }
338
339 pub fn on_event<F>(self, mut callback: F) -> Self
340 where
341 F: 'static + FnMut(Event, &mut MutableAppContext) -> bool,
342 {
343 let cx = self.0.clone();
344 self.0
345 .borrow_mut()
346 .foreground_platform
347 .on_event(Box::new(move |event| {
348 callback(event, &mut *cx.borrow_mut())
349 }));
350 self
351 }
352
353 pub fn on_open_files<F>(self, mut callback: F) -> Self
354 where
355 F: 'static + FnMut(Vec<PathBuf>, &mut MutableAppContext),
356 {
357 let cx = self.0.clone();
358 self.0
359 .borrow_mut()
360 .foreground_platform
361 .on_open_files(Box::new(move |paths| {
362 callback(paths, &mut *cx.borrow_mut())
363 }));
364 self
365 }
366
367 pub fn run<F>(self, on_finish_launching: F)
368 where
369 F: 'static + FnOnce(&mut MutableAppContext),
370 {
371 let platform = self.0.borrow().foreground_platform.clone();
372 platform.run(Box::new(move || {
373 let mut cx = self.0.borrow_mut();
374 let cx = &mut *cx;
375 crate::views::init(cx);
376 on_finish_launching(cx);
377 }))
378 }
379
380 pub fn platform(&self) -> Arc<dyn Platform> {
381 self.0.borrow().platform()
382 }
383
384 pub fn font_cache(&self) -> Arc<FontCache> {
385 self.0.borrow().cx.font_cache.clone()
386 }
387
388 fn update<T, F: FnOnce(&mut MutableAppContext) -> T>(&mut self, callback: F) -> T {
389 let mut state = self.0.borrow_mut();
390 let result = state.update(callback);
391 state.pending_notifications.clear();
392 result
393 }
394}
395
396#[cfg(any(test, feature = "test-support"))]
397impl TestAppContext {
398 pub fn new(
399 foreground_platform: Rc<platform::test::ForegroundPlatform>,
400 platform: Arc<dyn Platform>,
401 foreground: Rc<executor::Foreground>,
402 background: Arc<executor::Background>,
403 font_cache: Arc<FontCache>,
404 leak_detector: Arc<Mutex<LeakDetector>>,
405 first_entity_id: usize,
406 ) -> Self {
407 let mut cx = MutableAppContext::new(
408 foreground.clone(),
409 background,
410 platform,
411 foreground_platform.clone(),
412 font_cache,
413 RefCounts {
414 #[cfg(any(test, feature = "test-support"))]
415 leak_detector,
416 ..Default::default()
417 },
418 (),
419 );
420 cx.next_entity_id = first_entity_id;
421 let cx = TestAppContext {
422 cx: Rc::new(RefCell::new(cx)),
423 foreground_platform,
424 };
425 cx.cx.borrow_mut().weak_self = Some(Rc::downgrade(&cx.cx));
426 cx
427 }
428
429 pub fn dispatch_action<A: Action>(&self, window_id: usize, action: A) {
430 let mut cx = self.cx.borrow_mut();
431 let responder_chain = cx
432 .presenters_and_platform_windows
433 .get(&window_id)
434 .unwrap()
435 .0
436 .borrow()
437 .dispatch_path(cx.as_ref());
438
439 cx.dispatch_action_any(window_id, &responder_chain, &action);
440 }
441
442 pub fn dispatch_global_action<A: Action>(&self, action: A) {
443 self.cx.borrow_mut().dispatch_global_action(action);
444 }
445
446 pub fn dispatch_keystroke(
447 &mut self,
448 window_id: usize,
449 keystroke: Keystroke,
450 input: Option<String>,
451 is_held: bool,
452 ) {
453 self.cx.borrow_mut().update(|cx| {
454 let presenter = cx
455 .presenters_and_platform_windows
456 .get(&window_id)
457 .unwrap()
458 .0
459 .clone();
460 let responder_chain = presenter.borrow().dispatch_path(cx.as_ref());
461
462 if !cx.dispatch_keystroke(window_id, responder_chain, &keystroke) {
463 presenter.borrow_mut().dispatch_event(
464 Event::KeyDown {
465 keystroke,
466 input,
467 is_held,
468 },
469 cx,
470 );
471 }
472 });
473 }
474
475 pub fn add_model<T, F>(&mut self, build_model: F) -> ModelHandle<T>
476 where
477 T: Entity,
478 F: FnOnce(&mut ModelContext<T>) -> T,
479 {
480 self.cx.borrow_mut().add_model(build_model)
481 }
482
483 pub fn add_window<T, F>(&mut self, build_root_view: F) -> (usize, ViewHandle<T>)
484 where
485 T: View,
486 F: FnOnce(&mut ViewContext<T>) -> T,
487 {
488 self.cx
489 .borrow_mut()
490 .add_window(Default::default(), build_root_view)
491 }
492
493 pub fn window_ids(&self) -> Vec<usize> {
494 self.cx.borrow().window_ids().collect()
495 }
496
497 pub fn root_view<T: View>(&self, window_id: usize) -> Option<ViewHandle<T>> {
498 self.cx.borrow().root_view(window_id)
499 }
500
501 pub fn add_view<T, F>(&mut self, window_id: usize, build_view: F) -> ViewHandle<T>
502 where
503 T: View,
504 F: FnOnce(&mut ViewContext<T>) -> T,
505 {
506 self.cx.borrow_mut().add_view(window_id, build_view)
507 }
508
509 pub fn add_option_view<T, F>(
510 &mut self,
511 window_id: usize,
512 build_view: F,
513 ) -> Option<ViewHandle<T>>
514 where
515 T: View,
516 F: FnOnce(&mut ViewContext<T>) -> Option<T>,
517 {
518 self.cx.borrow_mut().add_option_view(window_id, build_view)
519 }
520
521 pub fn read<T, F: FnOnce(&AppContext) -> T>(&self, callback: F) -> T {
522 callback(self.cx.borrow().as_ref())
523 }
524
525 pub fn update<T, F: FnOnce(&mut MutableAppContext) -> T>(&mut self, callback: F) -> T {
526 let mut state = self.cx.borrow_mut();
527 // Don't increment pending flushes in order for effects to be flushed before the callback
528 // completes, which is helpful in tests.
529 let result = callback(&mut *state);
530 // Flush effects after the callback just in case there are any. This can happen in edge
531 // cases such as the closure dropping handles.
532 state.flush_effects();
533 result
534 }
535
536 pub fn to_async(&self) -> AsyncAppContext {
537 AsyncAppContext(self.cx.clone())
538 }
539
540 pub fn font_cache(&self) -> Arc<FontCache> {
541 self.cx.borrow().cx.font_cache.clone()
542 }
543
544 pub fn foreground_platform(&self) -> Rc<platform::test::ForegroundPlatform> {
545 self.foreground_platform.clone()
546 }
547
548 pub fn platform(&self) -> Arc<dyn platform::Platform> {
549 self.cx.borrow().cx.platform.clone()
550 }
551
552 pub fn foreground(&self) -> Rc<executor::Foreground> {
553 self.cx.borrow().foreground().clone()
554 }
555
556 pub fn background(&self) -> Arc<executor::Background> {
557 self.cx.borrow().background().clone()
558 }
559
560 pub fn spawn<F, Fut, T>(&self, f: F) -> Task<T>
561 where
562 F: FnOnce(AsyncAppContext) -> Fut,
563 Fut: 'static + Future<Output = T>,
564 T: 'static,
565 {
566 self.cx.borrow_mut().spawn(f)
567 }
568
569 pub fn simulate_new_path_selection(&self, result: impl FnOnce(PathBuf) -> Option<PathBuf>) {
570 self.foreground_platform.simulate_new_path_selection(result);
571 }
572
573 pub fn did_prompt_for_new_path(&self) -> bool {
574 self.foreground_platform.as_ref().did_prompt_for_new_path()
575 }
576
577 pub fn simulate_prompt_answer(&self, window_id: usize, answer: usize) {
578 use postage::prelude::Sink as _;
579
580 let mut state = self.cx.borrow_mut();
581 let (_, window) = state
582 .presenters_and_platform_windows
583 .get_mut(&window_id)
584 .unwrap();
585 let test_window = window
586 .as_any_mut()
587 .downcast_mut::<platform::test::Window>()
588 .unwrap();
589 let mut done_tx = test_window
590 .last_prompt
591 .take()
592 .expect("prompt was not called");
593 let _ = done_tx.try_send(answer);
594 }
595
596 #[cfg(any(test, feature = "test-support"))]
597 pub fn leak_detector(&self) -> Arc<Mutex<LeakDetector>> {
598 self.cx.borrow().leak_detector()
599 }
600}
601
602impl AsyncAppContext {
603 pub fn spawn<F, Fut, T>(&self, f: F) -> Task<T>
604 where
605 F: FnOnce(AsyncAppContext) -> Fut,
606 Fut: 'static + Future<Output = T>,
607 T: 'static,
608 {
609 self.0.borrow().foreground.spawn(f(self.clone()))
610 }
611
612 pub fn read<T, F: FnOnce(&AppContext) -> T>(&mut self, callback: F) -> T {
613 callback(self.0.borrow().as_ref())
614 }
615
616 pub fn update<T, F: FnOnce(&mut MutableAppContext) -> T>(&mut self, callback: F) -> T {
617 self.0.borrow_mut().update(callback)
618 }
619
620 pub fn add_model<T, F>(&mut self, build_model: F) -> ModelHandle<T>
621 where
622 T: Entity,
623 F: FnOnce(&mut ModelContext<T>) -> T,
624 {
625 self.update(|cx| cx.add_model(build_model))
626 }
627
628 pub fn add_view<T, F>(&mut self, window_id: usize, build_view: F) -> ViewHandle<T>
629 where
630 T: View,
631 F: FnOnce(&mut ViewContext<T>) -> T,
632 {
633 self.update(|cx| cx.add_view(window_id, build_view))
634 }
635
636 pub fn platform(&self) -> Arc<dyn Platform> {
637 self.0.borrow().platform()
638 }
639
640 pub fn foreground(&self) -> Rc<executor::Foreground> {
641 self.0.borrow().foreground.clone()
642 }
643
644 pub fn background(&self) -> Arc<executor::Background> {
645 self.0.borrow().cx.background.clone()
646 }
647}
648
649impl UpdateModel for AsyncAppContext {
650 fn update_model<E: Entity, O>(
651 &mut self,
652 handle: &ModelHandle<E>,
653 update: &mut dyn FnMut(&mut E, &mut ModelContext<E>) -> O,
654 ) -> O {
655 self.0.borrow_mut().update_model(handle, update)
656 }
657}
658
659impl UpgradeModelHandle for AsyncAppContext {
660 fn upgrade_model_handle<T: Entity>(
661 &self,
662 handle: &WeakModelHandle<T>,
663 ) -> Option<ModelHandle<T>> {
664 self.0.borrow().upgrade_model_handle(handle)
665 }
666
667 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
668 self.0.borrow().model_handle_is_upgradable(handle)
669 }
670
671 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
672 self.0.borrow().upgrade_any_model_handle(handle)
673 }
674}
675
676impl UpgradeViewHandle for AsyncAppContext {
677 fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
678 self.0.borrow_mut().upgrade_view_handle(handle)
679 }
680
681 fn upgrade_any_view_handle(&self, handle: &AnyWeakViewHandle) -> Option<AnyViewHandle> {
682 self.0.borrow_mut().upgrade_any_view_handle(handle)
683 }
684}
685
686impl ReadModelWith for AsyncAppContext {
687 fn read_model_with<E: Entity, T>(
688 &self,
689 handle: &ModelHandle<E>,
690 read: &mut dyn FnMut(&E, &AppContext) -> T,
691 ) -> T {
692 let cx = self.0.borrow();
693 let cx = cx.as_ref();
694 read(handle.read(cx), cx)
695 }
696}
697
698impl UpdateView for AsyncAppContext {
699 fn update_view<T, S>(
700 &mut self,
701 handle: &ViewHandle<T>,
702 update: &mut dyn FnMut(&mut T, &mut ViewContext<T>) -> S,
703 ) -> S
704 where
705 T: View,
706 {
707 self.0.borrow_mut().update_view(handle, update)
708 }
709}
710
711impl ReadViewWith for AsyncAppContext {
712 fn read_view_with<V, T>(
713 &self,
714 handle: &ViewHandle<V>,
715 read: &mut dyn FnMut(&V, &AppContext) -> T,
716 ) -> T
717 where
718 V: View,
719 {
720 let cx = self.0.borrow();
721 let cx = cx.as_ref();
722 read(handle.read(cx), cx)
723 }
724}
725
726#[cfg(any(test, feature = "test-support"))]
727impl UpdateModel for TestAppContext {
728 fn update_model<T: Entity, O>(
729 &mut self,
730 handle: &ModelHandle<T>,
731 update: &mut dyn FnMut(&mut T, &mut ModelContext<T>) -> O,
732 ) -> O {
733 self.cx.borrow_mut().update_model(handle, update)
734 }
735}
736
737#[cfg(any(test, feature = "test-support"))]
738impl ReadModelWith for TestAppContext {
739 fn read_model_with<E: Entity, T>(
740 &self,
741 handle: &ModelHandle<E>,
742 read: &mut dyn FnMut(&E, &AppContext) -> T,
743 ) -> T {
744 let cx = self.cx.borrow();
745 let cx = cx.as_ref();
746 read(handle.read(cx), cx)
747 }
748}
749
750#[cfg(any(test, feature = "test-support"))]
751impl UpdateView for TestAppContext {
752 fn update_view<T, S>(
753 &mut self,
754 handle: &ViewHandle<T>,
755 update: &mut dyn FnMut(&mut T, &mut ViewContext<T>) -> S,
756 ) -> S
757 where
758 T: View,
759 {
760 self.cx.borrow_mut().update_view(handle, update)
761 }
762}
763
764#[cfg(any(test, feature = "test-support"))]
765impl ReadViewWith for TestAppContext {
766 fn read_view_with<V, T>(
767 &self,
768 handle: &ViewHandle<V>,
769 read: &mut dyn FnMut(&V, &AppContext) -> T,
770 ) -> T
771 where
772 V: View,
773 {
774 let cx = self.cx.borrow();
775 let cx = cx.as_ref();
776 read(handle.read(cx), cx)
777 }
778}
779
780type ActionCallback =
781 dyn FnMut(&mut dyn AnyView, &dyn AnyAction, &mut MutableAppContext, usize, usize);
782type GlobalActionCallback = dyn FnMut(&dyn AnyAction, &mut MutableAppContext);
783
784type SubscriptionCallback = Box<dyn FnMut(&dyn Any, &mut MutableAppContext) -> bool>;
785type GlobalSubscriptionCallback = Box<dyn FnMut(&dyn Any, &mut MutableAppContext)>;
786type ObservationCallback = Box<dyn FnMut(&mut MutableAppContext) -> bool>;
787type GlobalObservationCallback = Box<dyn FnMut(&dyn Any, &mut MutableAppContext)>;
788type ReleaseObservationCallback = Box<dyn FnMut(&dyn Any, &mut MutableAppContext)>;
789
790pub struct MutableAppContext {
791 weak_self: Option<rc::Weak<RefCell<Self>>>,
792 foreground_platform: Rc<dyn platform::ForegroundPlatform>,
793 assets: Arc<AssetCache>,
794 cx: AppContext,
795 capture_actions: HashMap<TypeId, HashMap<TypeId, Vec<Box<ActionCallback>>>>,
796 actions: HashMap<TypeId, HashMap<TypeId, Vec<Box<ActionCallback>>>>,
797 global_actions: HashMap<TypeId, Box<GlobalActionCallback>>,
798 keystroke_matcher: keymap::Matcher,
799 next_entity_id: usize,
800 next_window_id: usize,
801 next_subscription_id: usize,
802 frame_count: usize,
803 subscriptions: Arc<Mutex<HashMap<usize, BTreeMap<usize, Option<SubscriptionCallback>>>>>,
804 global_subscriptions:
805 Arc<Mutex<HashMap<TypeId, BTreeMap<usize, Option<GlobalSubscriptionCallback>>>>>,
806 observations: Arc<Mutex<HashMap<usize, BTreeMap<usize, Option<ObservationCallback>>>>>,
807 global_observations:
808 Arc<Mutex<HashMap<TypeId, BTreeMap<usize, Option<GlobalObservationCallback>>>>>,
809 release_observations: Arc<Mutex<HashMap<usize, BTreeMap<usize, ReleaseObservationCallback>>>>,
810 presenters_and_platform_windows:
811 HashMap<usize, (Rc<RefCell<Presenter>>, Box<dyn platform::Window>)>,
812 foreground: Rc<executor::Foreground>,
813 pending_effects: VecDeque<Effect>,
814 pending_notifications: HashSet<usize>,
815 pending_global_notifications: HashSet<TypeId>,
816 pending_flushes: usize,
817 flushing_effects: bool,
818 next_cursor_style_handle_id: Arc<AtomicUsize>,
819 halt_action_dispatch: bool,
820}
821
822impl MutableAppContext {
823 fn new(
824 foreground: Rc<executor::Foreground>,
825 background: Arc<executor::Background>,
826 platform: Arc<dyn platform::Platform>,
827 foreground_platform: Rc<dyn platform::ForegroundPlatform>,
828 font_cache: Arc<FontCache>,
829 ref_counts: RefCounts,
830 asset_source: impl AssetSource,
831 ) -> Self {
832 Self {
833 weak_self: None,
834 foreground_platform,
835 assets: Arc::new(AssetCache::new(asset_source)),
836 cx: AppContext {
837 models: Default::default(),
838 views: Default::default(),
839 windows: Default::default(),
840 globals: Default::default(),
841 element_states: Default::default(),
842 ref_counts: Arc::new(Mutex::new(ref_counts)),
843 background,
844 font_cache,
845 platform,
846 },
847 capture_actions: HashMap::new(),
848 actions: HashMap::new(),
849 global_actions: HashMap::new(),
850 keystroke_matcher: keymap::Matcher::default(),
851 next_entity_id: 0,
852 next_window_id: 0,
853 next_subscription_id: 0,
854 frame_count: 0,
855 subscriptions: Default::default(),
856 global_subscriptions: Default::default(),
857 observations: Default::default(),
858 release_observations: Default::default(),
859 global_observations: Default::default(),
860 presenters_and_platform_windows: HashMap::new(),
861 foreground,
862 pending_effects: VecDeque::new(),
863 pending_notifications: HashSet::new(),
864 pending_global_notifications: HashSet::new(),
865 pending_flushes: 0,
866 flushing_effects: false,
867 next_cursor_style_handle_id: Default::default(),
868 halt_action_dispatch: false,
869 }
870 }
871
872 pub fn upgrade(&self) -> App {
873 App(self.weak_self.as_ref().unwrap().upgrade().unwrap())
874 }
875
876 pub fn quit(&mut self) {
877 let mut futures = Vec::new();
878 for model_id in self.cx.models.keys().copied().collect::<Vec<_>>() {
879 let mut model = self.cx.models.remove(&model_id).unwrap();
880 futures.extend(model.app_will_quit(self));
881 self.cx.models.insert(model_id, model);
882 }
883
884 for view_id in self.cx.views.keys().copied().collect::<Vec<_>>() {
885 let mut view = self.cx.views.remove(&view_id).unwrap();
886 futures.extend(view.app_will_quit(self));
887 self.cx.views.insert(view_id, view);
888 }
889
890 self.remove_all_windows();
891
892 let futures = futures::future::join_all(futures);
893 if self
894 .background
895 .block_with_timeout(Duration::from_millis(100), futures)
896 .is_err()
897 {
898 log::error!("timed out waiting on app_will_quit");
899 }
900 }
901
902 pub fn remove_all_windows(&mut self) {
903 for (window_id, _) in self.cx.windows.drain() {
904 self.presenters_and_platform_windows.remove(&window_id);
905 }
906 self.flush_effects();
907 }
908
909 pub fn platform(&self) -> Arc<dyn platform::Platform> {
910 self.cx.platform.clone()
911 }
912
913 pub fn font_cache(&self) -> &Arc<FontCache> {
914 &self.cx.font_cache
915 }
916
917 pub fn foreground(&self) -> &Rc<executor::Foreground> {
918 &self.foreground
919 }
920
921 pub fn background(&self) -> &Arc<executor::Background> {
922 &self.cx.background
923 }
924
925 pub fn debug_elements(&self, window_id: usize) -> Option<crate::json::Value> {
926 self.presenters_and_platform_windows
927 .get(&window_id)
928 .and_then(|(presenter, _)| presenter.borrow().debug_elements(self))
929 }
930
931 pub fn add_action<A, V, F>(&mut self, handler: F)
932 where
933 A: Action,
934 V: View,
935 F: 'static + FnMut(&mut V, &A, &mut ViewContext<V>),
936 {
937 self.add_action_internal(handler, false)
938 }
939
940 pub fn capture_action<A, V, F>(&mut self, handler: F)
941 where
942 A: Action,
943 V: View,
944 F: 'static + FnMut(&mut V, &A, &mut ViewContext<V>),
945 {
946 self.add_action_internal(handler, true)
947 }
948
949 fn add_action_internal<A, V, F>(&mut self, mut handler: F, capture: bool)
950 where
951 A: Action,
952 V: View,
953 F: 'static + FnMut(&mut V, &A, &mut ViewContext<V>),
954 {
955 let handler = Box::new(
956 move |view: &mut dyn AnyView,
957 action: &dyn AnyAction,
958 cx: &mut MutableAppContext,
959 window_id: usize,
960 view_id: usize| {
961 let action = action.as_any().downcast_ref().unwrap();
962 let mut cx = ViewContext::new(cx, window_id, view_id);
963 handler(
964 view.as_any_mut()
965 .downcast_mut()
966 .expect("downcast is type safe"),
967 action,
968 &mut cx,
969 );
970 },
971 );
972
973 let actions = if capture {
974 &mut self.capture_actions
975 } else {
976 &mut self.actions
977 };
978
979 actions
980 .entry(TypeId::of::<V>())
981 .or_default()
982 .entry(TypeId::of::<A>())
983 .or_default()
984 .push(handler);
985 }
986
987 pub fn add_async_action<A, V, F>(&mut self, mut handler: F)
988 where
989 A: Action,
990 V: View,
991 F: 'static + FnMut(&mut V, &A, &mut ViewContext<V>) -> Option<Task<Result<()>>>,
992 {
993 self.add_action(move |view, action, cx| {
994 handler(view, action, cx).map(|task| task.detach_and_log_err(cx));
995 })
996 }
997
998 pub fn add_global_action<A, F>(&mut self, mut handler: F)
999 where
1000 A: Action,
1001 F: 'static + FnMut(&A, &mut MutableAppContext),
1002 {
1003 let handler = Box::new(move |action: &dyn AnyAction, cx: &mut MutableAppContext| {
1004 let action = action.as_any().downcast_ref().unwrap();
1005 handler(action, cx);
1006 });
1007
1008 if self
1009 .global_actions
1010 .insert(TypeId::of::<A>(), handler)
1011 .is_some()
1012 {
1013 panic!("registered multiple global handlers for the same action type");
1014 }
1015 }
1016
1017 pub fn window_ids(&self) -> impl Iterator<Item = usize> + '_ {
1018 self.cx.windows.keys().cloned()
1019 }
1020
1021 pub fn activate_window(&self, window_id: usize) {
1022 if let Some((_, window)) = self.presenters_and_platform_windows.get(&window_id) {
1023 window.activate()
1024 }
1025 }
1026
1027 pub fn root_view<T: View>(&self, window_id: usize) -> Option<ViewHandle<T>> {
1028 self.cx
1029 .windows
1030 .get(&window_id)
1031 .and_then(|window| window.root_view.clone().downcast::<T>())
1032 }
1033
1034 pub fn render_view(
1035 &mut self,
1036 window_id: usize,
1037 view_id: usize,
1038 titlebar_height: f32,
1039 refreshing: bool,
1040 ) -> Result<ElementBox> {
1041 let mut view = self
1042 .cx
1043 .views
1044 .remove(&(window_id, view_id))
1045 .ok_or(anyhow!("view not found"))?;
1046 let element = view.render(window_id, view_id, titlebar_height, refreshing, self);
1047 self.cx.views.insert((window_id, view_id), view);
1048 Ok(element)
1049 }
1050
1051 pub fn render_views(
1052 &mut self,
1053 window_id: usize,
1054 titlebar_height: f32,
1055 ) -> HashMap<usize, ElementBox> {
1056 self.start_frame();
1057 let view_ids = self
1058 .views
1059 .keys()
1060 .filter_map(|(win_id, view_id)| {
1061 if *win_id == window_id {
1062 Some(*view_id)
1063 } else {
1064 None
1065 }
1066 })
1067 .collect::<Vec<_>>();
1068 view_ids
1069 .into_iter()
1070 .map(|view_id| {
1071 (
1072 view_id,
1073 self.render_view(window_id, view_id, titlebar_height, false)
1074 .unwrap(),
1075 )
1076 })
1077 .collect()
1078 }
1079
1080 pub(crate) fn start_frame(&mut self) {
1081 self.frame_count += 1;
1082 }
1083
1084 pub fn update<T, F: FnOnce(&mut Self) -> T>(&mut self, callback: F) -> T {
1085 self.pending_flushes += 1;
1086 let result = callback(self);
1087 self.flush_effects();
1088 result
1089 }
1090
1091 pub fn set_menus(&mut self, menus: Vec<Menu>) {
1092 self.foreground_platform.set_menus(menus);
1093 }
1094
1095 fn prompt(
1096 &self,
1097 window_id: usize,
1098 level: PromptLevel,
1099 msg: &str,
1100 answers: &[&str],
1101 ) -> oneshot::Receiver<usize> {
1102 let (_, window) = &self.presenters_and_platform_windows[&window_id];
1103 window.prompt(level, msg, answers)
1104 }
1105
1106 pub fn prompt_for_paths(
1107 &self,
1108 options: PathPromptOptions,
1109 ) -> oneshot::Receiver<Option<Vec<PathBuf>>> {
1110 self.foreground_platform.prompt_for_paths(options)
1111 }
1112
1113 pub fn prompt_for_new_path(&self, directory: &Path) -> oneshot::Receiver<Option<PathBuf>> {
1114 self.foreground_platform.prompt_for_new_path(directory)
1115 }
1116
1117 pub fn emit_global<E: Any>(&mut self, payload: E) {
1118 self.pending_effects.push_back(Effect::GlobalEvent {
1119 payload: Box::new(payload),
1120 });
1121 }
1122
1123 pub fn subscribe<E, H, F>(&mut self, handle: &H, mut callback: F) -> Subscription
1124 where
1125 E: Entity,
1126 E::Event: 'static,
1127 H: Handle<E>,
1128 F: 'static + FnMut(H, &E::Event, &mut Self),
1129 {
1130 self.subscribe_internal(handle, move |handle, event, cx| {
1131 callback(handle, event, cx);
1132 true
1133 })
1134 }
1135
1136 pub fn subscribe_global<E, F>(&mut self, mut callback: F) -> Subscription
1137 where
1138 E: Any,
1139 F: 'static + FnMut(&E, &mut Self),
1140 {
1141 let subscription_id = post_inc(&mut self.next_subscription_id);
1142 let type_id = TypeId::of::<E>();
1143 self.pending_effects.push_back(Effect::GlobalSubscription {
1144 type_id,
1145 subscription_id,
1146 callback: Box::new(move |payload, cx| {
1147 let payload = payload.downcast_ref().expect("downcast is type safe");
1148 callback(payload, cx)
1149 }),
1150 });
1151 Subscription::GlobalSubscription {
1152 id: subscription_id,
1153 type_id,
1154 subscriptions: Some(Arc::downgrade(&self.global_subscriptions)),
1155 }
1156 }
1157
1158 pub fn observe<E, H, F>(&mut self, handle: &H, mut callback: F) -> Subscription
1159 where
1160 E: Entity,
1161 E::Event: 'static,
1162 H: Handle<E>,
1163 F: 'static + FnMut(H, &mut Self),
1164 {
1165 self.observe_internal(handle, move |handle, cx| {
1166 callback(handle, cx);
1167 true
1168 })
1169 }
1170
1171 pub fn subscribe_internal<E, H, F>(&mut self, handle: &H, mut callback: F) -> Subscription
1172 where
1173 E: Entity,
1174 E::Event: 'static,
1175 H: Handle<E>,
1176 F: 'static + FnMut(H, &E::Event, &mut Self) -> bool,
1177 {
1178 let subscription_id = post_inc(&mut self.next_subscription_id);
1179 let emitter = handle.downgrade();
1180 self.pending_effects.push_back(Effect::Subscription {
1181 entity_id: handle.id(),
1182 subscription_id,
1183 callback: Box::new(move |payload, cx| {
1184 if let Some(emitter) = H::upgrade_from(&emitter, cx.as_ref()) {
1185 let payload = payload.downcast_ref().expect("downcast is type safe");
1186 callback(emitter, payload, cx)
1187 } else {
1188 false
1189 }
1190 }),
1191 });
1192 Subscription::Subscription {
1193 id: subscription_id,
1194 entity_id: handle.id(),
1195 subscriptions: Some(Arc::downgrade(&self.subscriptions)),
1196 }
1197 }
1198
1199 fn observe_internal<E, H, F>(&mut self, handle: &H, mut callback: F) -> Subscription
1200 where
1201 E: Entity,
1202 E::Event: 'static,
1203 H: Handle<E>,
1204 F: 'static + FnMut(H, &mut Self) -> bool,
1205 {
1206 let subscription_id = post_inc(&mut self.next_subscription_id);
1207 let observed = handle.downgrade();
1208 let entity_id = handle.id();
1209 self.pending_effects.push_back(Effect::Observation {
1210 entity_id,
1211 subscription_id,
1212 callback: Box::new(move |cx| {
1213 if let Some(observed) = H::upgrade_from(&observed, cx) {
1214 callback(observed, cx)
1215 } else {
1216 false
1217 }
1218 }),
1219 });
1220 Subscription::Observation {
1221 id: subscription_id,
1222 entity_id,
1223 observations: Some(Arc::downgrade(&self.observations)),
1224 }
1225 }
1226
1227 pub fn observe_global<G, F>(&mut self, mut observe: F) -> Subscription
1228 where
1229 G: Any,
1230 F: 'static + FnMut(&G, &mut MutableAppContext),
1231 {
1232 let type_id = TypeId::of::<G>();
1233 let id = post_inc(&mut self.next_subscription_id);
1234
1235 self.global_observations
1236 .lock()
1237 .entry(type_id)
1238 .or_default()
1239 .insert(
1240 id,
1241 Some(
1242 Box::new(move |global: &dyn Any, cx: &mut MutableAppContext| {
1243 observe(global.downcast_ref().unwrap(), cx)
1244 }) as GlobalObservationCallback,
1245 ),
1246 );
1247
1248 Subscription::GlobalObservation {
1249 id,
1250 type_id,
1251 observations: Some(Arc::downgrade(&self.global_observations)),
1252 }
1253 }
1254
1255 pub fn observe_release<E, H, F>(&mut self, handle: &H, mut callback: F) -> Subscription
1256 where
1257 E: Entity,
1258 E::Event: 'static,
1259 H: Handle<E>,
1260 F: 'static + FnMut(&E, &mut Self),
1261 {
1262 let id = post_inc(&mut self.next_subscription_id);
1263 self.release_observations
1264 .lock()
1265 .entry(handle.id())
1266 .or_default()
1267 .insert(
1268 id,
1269 Box::new(move |released, cx| {
1270 let released = released.downcast_ref().unwrap();
1271 callback(released, cx)
1272 }),
1273 );
1274 Subscription::ReleaseObservation {
1275 id,
1276 entity_id: handle.id(),
1277 observations: Some(Arc::downgrade(&self.release_observations)),
1278 }
1279 }
1280
1281 pub fn defer(&mut self, callback: impl 'static + FnOnce(&mut MutableAppContext)) {
1282 self.pending_effects.push_back(Effect::Deferred {
1283 callback: Box::new(callback),
1284 after_window_update: false,
1285 })
1286 }
1287
1288 pub fn after_window_update(&mut self, callback: impl 'static + FnOnce(&mut MutableAppContext)) {
1289 self.pending_effects.push_back(Effect::Deferred {
1290 callback: Box::new(callback),
1291 after_window_update: true,
1292 })
1293 }
1294
1295 pub(crate) fn notify_model(&mut self, model_id: usize) {
1296 if self.pending_notifications.insert(model_id) {
1297 self.pending_effects
1298 .push_back(Effect::ModelNotification { model_id });
1299 }
1300 }
1301
1302 pub(crate) fn notify_view(&mut self, window_id: usize, view_id: usize) {
1303 if self.pending_notifications.insert(view_id) {
1304 self.pending_effects
1305 .push_back(Effect::ViewNotification { window_id, view_id });
1306 }
1307 }
1308
1309 pub(crate) fn notify_global(&mut self, type_id: TypeId) {
1310 if self.pending_global_notifications.insert(type_id) {
1311 self.pending_effects
1312 .push_back(Effect::GlobalNotification { type_id });
1313 }
1314 }
1315
1316 pub fn dispatch_action<A: Action>(
1317 &mut self,
1318 window_id: usize,
1319 responder_chain: Vec<usize>,
1320 action: &A,
1321 ) {
1322 self.dispatch_action_any(window_id, &responder_chain, action);
1323 }
1324
1325 pub(crate) fn dispatch_action_any(
1326 &mut self,
1327 window_id: usize,
1328 path: &[usize],
1329 action: &dyn AnyAction,
1330 ) -> bool {
1331 self.update(|this| {
1332 this.halt_action_dispatch = false;
1333 for (capture_phase, view_id) in path
1334 .iter()
1335 .map(|view_id| (true, *view_id))
1336 .chain(path.iter().rev().map(|view_id| (false, *view_id)))
1337 {
1338 if let Some(mut view) = this.cx.views.remove(&(window_id, view_id)) {
1339 let type_id = view.as_any().type_id();
1340
1341 if let Some((name, mut handlers)) = this
1342 .actions_mut(capture_phase)
1343 .get_mut(&type_id)
1344 .and_then(|h| h.remove_entry(&action.id()))
1345 {
1346 for handler in handlers.iter_mut().rev() {
1347 this.halt_action_dispatch = true;
1348 handler(view.as_mut(), action, this, window_id, view_id);
1349 if this.halt_action_dispatch {
1350 break;
1351 }
1352 }
1353 this.actions_mut(capture_phase)
1354 .get_mut(&type_id)
1355 .unwrap()
1356 .insert(name, handlers);
1357 }
1358
1359 this.cx.views.insert((window_id, view_id), view);
1360
1361 if this.halt_action_dispatch {
1362 break;
1363 }
1364 }
1365 }
1366
1367 if !this.halt_action_dispatch {
1368 this.halt_action_dispatch = this.dispatch_global_action_any(action);
1369 }
1370 this.halt_action_dispatch
1371 })
1372 }
1373
1374 fn actions_mut(
1375 &mut self,
1376 capture_phase: bool,
1377 ) -> &mut HashMap<TypeId, HashMap<TypeId, Vec<Box<ActionCallback>>>> {
1378 if capture_phase {
1379 &mut self.capture_actions
1380 } else {
1381 &mut self.actions
1382 }
1383 }
1384
1385 pub fn dispatch_global_action<A: Action>(&mut self, action: A) {
1386 self.dispatch_global_action_any(&action);
1387 }
1388
1389 fn dispatch_global_action_any(&mut self, action: &dyn AnyAction) -> bool {
1390 self.update(|this| {
1391 if let Some((name, mut handler)) = this.global_actions.remove_entry(&action.id()) {
1392 handler(action, this);
1393 this.global_actions.insert(name, handler);
1394 true
1395 } else {
1396 false
1397 }
1398 })
1399 }
1400
1401 pub fn add_bindings<T: IntoIterator<Item = keymap::Binding>>(&mut self, bindings: T) {
1402 self.keystroke_matcher.add_bindings(bindings);
1403 }
1404
1405 pub fn dispatch_keystroke(
1406 &mut self,
1407 window_id: usize,
1408 responder_chain: Vec<usize>,
1409 keystroke: &Keystroke,
1410 ) -> bool {
1411 let mut context_chain = Vec::new();
1412 for view_id in &responder_chain {
1413 let view = self
1414 .cx
1415 .views
1416 .get(&(window_id, *view_id))
1417 .expect("view in responder chain does not exist");
1418 context_chain.push(view.keymap_context(self.as_ref()));
1419 }
1420
1421 let mut pending = false;
1422 for (i, cx) in context_chain.iter().enumerate().rev() {
1423 match self
1424 .keystroke_matcher
1425 .push_keystroke(keystroke.clone(), responder_chain[i], cx)
1426 {
1427 MatchResult::None => {}
1428 MatchResult::Pending => pending = true,
1429 MatchResult::Action(action) => {
1430 if self.dispatch_action_any(window_id, &responder_chain[0..=i], action.as_ref())
1431 {
1432 self.keystroke_matcher.clear_pending();
1433 return true;
1434 }
1435 }
1436 }
1437 }
1438
1439 pending
1440 }
1441
1442 pub fn default_global<T: 'static + Default>(&mut self) -> &T {
1443 let type_id = TypeId::of::<T>();
1444 self.update(|this| {
1445 if !this.globals.contains_key(&type_id) {
1446 this.notify_global(type_id);
1447 }
1448
1449 this.cx
1450 .globals
1451 .entry(type_id)
1452 .or_insert_with(|| Box::new(T::default()));
1453 });
1454 self.globals.get(&type_id).unwrap().downcast_ref().unwrap()
1455 }
1456
1457 pub fn set_global<T: 'static>(&mut self, state: T) {
1458 self.update(|this| {
1459 let type_id = TypeId::of::<T>();
1460 this.cx.globals.insert(type_id, Box::new(state));
1461 this.notify_global(type_id);
1462 });
1463 }
1464
1465 pub fn update_default_global<T, F, U>(&mut self, update: F) -> U
1466 where
1467 T: 'static + Default,
1468 F: FnOnce(&mut T, &mut MutableAppContext) -> U,
1469 {
1470 self.update(|this| {
1471 let type_id = TypeId::of::<T>();
1472 let mut state = this
1473 .cx
1474 .globals
1475 .remove(&type_id)
1476 .unwrap_or_else(|| Box::new(T::default()));
1477 let result = update(state.downcast_mut().unwrap(), this);
1478 this.cx.globals.insert(type_id, state);
1479 this.notify_global(type_id);
1480 result
1481 })
1482 }
1483
1484 pub fn update_global<T, F, U>(&mut self, update: F) -> U
1485 where
1486 T: 'static,
1487 F: FnOnce(&mut T, &mut MutableAppContext) -> U,
1488 {
1489 self.update(|this| {
1490 let type_id = TypeId::of::<T>();
1491 let mut state = this
1492 .cx
1493 .globals
1494 .remove(&type_id)
1495 .expect("no global has been added for this type");
1496 let result = update(state.downcast_mut().unwrap(), this);
1497 this.cx.globals.insert(type_id, state);
1498 this.notify_global(type_id);
1499 result
1500 })
1501 }
1502
1503 pub fn add_model<T, F>(&mut self, build_model: F) -> ModelHandle<T>
1504 where
1505 T: Entity,
1506 F: FnOnce(&mut ModelContext<T>) -> T,
1507 {
1508 self.update(|this| {
1509 let model_id = post_inc(&mut this.next_entity_id);
1510 let handle = ModelHandle::new(model_id, &this.cx.ref_counts);
1511 let mut cx = ModelContext::new(this, model_id);
1512 let model = build_model(&mut cx);
1513 this.cx.models.insert(model_id, Box::new(model));
1514 handle
1515 })
1516 }
1517
1518 pub fn add_window<T, F>(
1519 &mut self,
1520 window_options: WindowOptions,
1521 build_root_view: F,
1522 ) -> (usize, ViewHandle<T>)
1523 where
1524 T: View,
1525 F: FnOnce(&mut ViewContext<T>) -> T,
1526 {
1527 self.update(|this| {
1528 let window_id = post_inc(&mut this.next_window_id);
1529 let root_view = this.add_view(window_id, build_root_view);
1530
1531 this.cx.windows.insert(
1532 window_id,
1533 Window {
1534 root_view: root_view.clone().into(),
1535 focused_view_id: Some(root_view.id()),
1536 invalidation: None,
1537 },
1538 );
1539 root_view.update(this, |view, cx| {
1540 view.on_focus(cx);
1541 });
1542 this.open_platform_window(window_id, window_options);
1543
1544 (window_id, root_view)
1545 })
1546 }
1547
1548 pub fn remove_window(&mut self, window_id: usize) {
1549 self.cx.windows.remove(&window_id);
1550 self.presenters_and_platform_windows.remove(&window_id);
1551 self.flush_effects();
1552 }
1553
1554 fn open_platform_window(&mut self, window_id: usize, window_options: WindowOptions) {
1555 let mut window =
1556 self.cx
1557 .platform
1558 .open_window(window_id, window_options, self.foreground.clone());
1559 let presenter = Rc::new(RefCell::new(
1560 self.build_presenter(window_id, window.titlebar_height()),
1561 ));
1562
1563 {
1564 let mut app = self.upgrade();
1565 let presenter = presenter.clone();
1566 window.on_event(Box::new(move |event| {
1567 app.update(|cx| {
1568 if let Event::KeyDown { keystroke, .. } = &event {
1569 if cx.dispatch_keystroke(
1570 window_id,
1571 presenter.borrow().dispatch_path(cx.as_ref()),
1572 keystroke,
1573 ) {
1574 return;
1575 }
1576 }
1577
1578 presenter.borrow_mut().dispatch_event(event, cx);
1579 })
1580 }));
1581 }
1582
1583 {
1584 let mut app = self.upgrade();
1585 window.on_resize(Box::new(move || {
1586 app.update(|cx| cx.resize_window(window_id))
1587 }));
1588 }
1589
1590 {
1591 let mut app = self.upgrade();
1592 window.on_close(Box::new(move || {
1593 app.update(|cx| cx.remove_window(window_id));
1594 }));
1595 }
1596
1597 let scene =
1598 presenter
1599 .borrow_mut()
1600 .build_scene(window.size(), window.scale_factor(), false, self);
1601 window.present_scene(scene);
1602 self.presenters_and_platform_windows
1603 .insert(window_id, (presenter.clone(), window));
1604 }
1605
1606 pub fn build_presenter(&mut self, window_id: usize, titlebar_height: f32) -> Presenter {
1607 Presenter::new(
1608 window_id,
1609 titlebar_height,
1610 self.cx.font_cache.clone(),
1611 TextLayoutCache::new(self.cx.platform.fonts()),
1612 self.assets.clone(),
1613 self,
1614 )
1615 }
1616
1617 pub fn build_render_context<V: View>(
1618 &mut self,
1619 window_id: usize,
1620 view_id: usize,
1621 titlebar_height: f32,
1622 refreshing: bool,
1623 ) -> RenderContext<V> {
1624 RenderContext {
1625 app: self,
1626 titlebar_height,
1627 refreshing,
1628 window_id,
1629 view_id,
1630 view_type: PhantomData,
1631 }
1632 }
1633
1634 pub fn add_view<T, F>(&mut self, window_id: usize, build_view: F) -> ViewHandle<T>
1635 where
1636 T: View,
1637 F: FnOnce(&mut ViewContext<T>) -> T,
1638 {
1639 self.add_option_view(window_id, |cx| Some(build_view(cx)))
1640 .unwrap()
1641 }
1642
1643 pub fn add_option_view<T, F>(
1644 &mut self,
1645 window_id: usize,
1646 build_view: F,
1647 ) -> Option<ViewHandle<T>>
1648 where
1649 T: View,
1650 F: FnOnce(&mut ViewContext<T>) -> Option<T>,
1651 {
1652 self.update(|this| {
1653 let view_id = post_inc(&mut this.next_entity_id);
1654 let mut cx = ViewContext::new(this, window_id, view_id);
1655 let handle = if let Some(view) = build_view(&mut cx) {
1656 this.cx.views.insert((window_id, view_id), Box::new(view));
1657 if let Some(window) = this.cx.windows.get_mut(&window_id) {
1658 window
1659 .invalidation
1660 .get_or_insert_with(Default::default)
1661 .updated
1662 .insert(view_id);
1663 }
1664 Some(ViewHandle::new(window_id, view_id, &this.cx.ref_counts))
1665 } else {
1666 None
1667 };
1668 handle
1669 })
1670 }
1671
1672 fn remove_dropped_entities(&mut self) {
1673 loop {
1674 let (dropped_models, dropped_views, dropped_element_states) =
1675 self.cx.ref_counts.lock().take_dropped();
1676 if dropped_models.is_empty()
1677 && dropped_views.is_empty()
1678 && dropped_element_states.is_empty()
1679 {
1680 break;
1681 }
1682
1683 for model_id in dropped_models {
1684 self.subscriptions.lock().remove(&model_id);
1685 self.observations.lock().remove(&model_id);
1686 let mut model = self.cx.models.remove(&model_id).unwrap();
1687 model.release(self);
1688 self.pending_effects
1689 .push_back(Effect::ModelRelease { model_id, model });
1690 }
1691
1692 for (window_id, view_id) in dropped_views {
1693 self.subscriptions.lock().remove(&view_id);
1694 self.observations.lock().remove(&view_id);
1695 let mut view = self.cx.views.remove(&(window_id, view_id)).unwrap();
1696 view.release(self);
1697 let change_focus_to = self.cx.windows.get_mut(&window_id).and_then(|window| {
1698 window
1699 .invalidation
1700 .get_or_insert_with(Default::default)
1701 .removed
1702 .push(view_id);
1703 if window.focused_view_id == Some(view_id) {
1704 Some(window.root_view.id())
1705 } else {
1706 None
1707 }
1708 });
1709
1710 if let Some(view_id) = change_focus_to {
1711 self.focus(window_id, Some(view_id));
1712 }
1713
1714 self.pending_effects
1715 .push_back(Effect::ViewRelease { view_id, view });
1716 }
1717
1718 for key in dropped_element_states {
1719 self.cx.element_states.remove(&key);
1720 }
1721 }
1722 }
1723
1724 fn flush_effects(&mut self) {
1725 self.pending_flushes = self.pending_flushes.saturating_sub(1);
1726 let mut after_window_update_callbacks = Vec::new();
1727
1728 if !self.flushing_effects && self.pending_flushes == 0 {
1729 self.flushing_effects = true;
1730
1731 let mut refreshing = false;
1732 loop {
1733 if let Some(effect) = self.pending_effects.pop_front() {
1734 match effect {
1735 Effect::Subscription {
1736 entity_id,
1737 subscription_id,
1738 callback,
1739 } => self.handle_subscription_effect(entity_id, subscription_id, callback),
1740 Effect::Event { entity_id, payload } => self.emit_event(entity_id, payload),
1741 Effect::GlobalSubscription {
1742 type_id,
1743 subscription_id,
1744 callback,
1745 } => self.handle_global_subscription_effect(
1746 type_id,
1747 subscription_id,
1748 callback,
1749 ),
1750 Effect::GlobalEvent { payload } => self.emit_global_event(payload),
1751 Effect::Observation {
1752 entity_id,
1753 subscription_id,
1754 callback,
1755 } => self.handle_observation_effect(entity_id, subscription_id, callback),
1756 Effect::ModelNotification { model_id } => {
1757 self.notify_model_observers(model_id)
1758 }
1759 Effect::ViewNotification { window_id, view_id } => {
1760 self.notify_view_observers(window_id, view_id)
1761 }
1762 Effect::GlobalNotification { type_id } => {
1763 self.notify_global_observers(type_id)
1764 }
1765 Effect::Deferred {
1766 callback,
1767 after_window_update,
1768 } => {
1769 if after_window_update {
1770 after_window_update_callbacks.push(callback);
1771 } else {
1772 callback(self)
1773 }
1774 }
1775 Effect::ModelRelease { model_id, model } => {
1776 self.notify_release_observers(model_id, model.as_any())
1777 }
1778 Effect::ViewRelease { view_id, view } => {
1779 self.notify_release_observers(view_id, view.as_any())
1780 }
1781 Effect::Focus { window_id, view_id } => {
1782 self.focus(window_id, view_id);
1783 }
1784 Effect::ResizeWindow { window_id } => {
1785 if let Some(window) = self.cx.windows.get_mut(&window_id) {
1786 window
1787 .invalidation
1788 .get_or_insert(WindowInvalidation::default());
1789 }
1790 }
1791 Effect::RefreshWindows => {
1792 refreshing = true;
1793 }
1794 }
1795 self.pending_notifications.clear();
1796 self.remove_dropped_entities();
1797 } else {
1798 self.remove_dropped_entities();
1799 if refreshing {
1800 self.perform_window_refresh();
1801 } else {
1802 self.update_windows();
1803 }
1804
1805 if self.pending_effects.is_empty() {
1806 for callback in after_window_update_callbacks.drain(..) {
1807 callback(self);
1808 }
1809
1810 if self.pending_effects.is_empty() {
1811 self.flushing_effects = false;
1812 self.pending_notifications.clear();
1813 self.pending_global_notifications.clear();
1814 break;
1815 }
1816 }
1817
1818 refreshing = false;
1819 }
1820 }
1821 }
1822 }
1823
1824 fn update_windows(&mut self) {
1825 let mut invalidations = HashMap::new();
1826 for (window_id, window) in &mut self.cx.windows {
1827 if let Some(invalidation) = window.invalidation.take() {
1828 invalidations.insert(*window_id, invalidation);
1829 }
1830 }
1831
1832 for (window_id, mut invalidation) in invalidations {
1833 if let Some((presenter, mut window)) =
1834 self.presenters_and_platform_windows.remove(&window_id)
1835 {
1836 {
1837 let mut presenter = presenter.borrow_mut();
1838 presenter.invalidate(&mut invalidation, self);
1839 let scene =
1840 presenter.build_scene(window.size(), window.scale_factor(), false, self);
1841 window.present_scene(scene);
1842 }
1843 self.presenters_and_platform_windows
1844 .insert(window_id, (presenter, window));
1845 }
1846 }
1847 }
1848
1849 fn resize_window(&mut self, window_id: usize) {
1850 self.pending_effects
1851 .push_back(Effect::ResizeWindow { window_id });
1852 }
1853
1854 pub fn refresh_windows(&mut self) {
1855 self.pending_effects.push_back(Effect::RefreshWindows);
1856 }
1857
1858 fn perform_window_refresh(&mut self) {
1859 let mut presenters = mem::take(&mut self.presenters_and_platform_windows);
1860 for (window_id, (presenter, window)) in &mut presenters {
1861 let mut invalidation = self
1862 .cx
1863 .windows
1864 .get_mut(&window_id)
1865 .unwrap()
1866 .invalidation
1867 .take();
1868 let mut presenter = presenter.borrow_mut();
1869 presenter.refresh(
1870 invalidation.as_mut().unwrap_or(&mut Default::default()),
1871 self,
1872 );
1873 let scene = presenter.build_scene(window.size(), window.scale_factor(), true, self);
1874 window.present_scene(scene);
1875 }
1876 self.presenters_and_platform_windows = presenters;
1877 }
1878
1879 pub fn set_cursor_style(&mut self, style: CursorStyle) -> CursorStyleHandle {
1880 self.platform.set_cursor_style(style);
1881 let id = self.next_cursor_style_handle_id.fetch_add(1, SeqCst);
1882 CursorStyleHandle {
1883 id,
1884 next_cursor_style_handle_id: self.next_cursor_style_handle_id.clone(),
1885 platform: self.platform(),
1886 }
1887 }
1888
1889 fn handle_subscription_effect(
1890 &mut self,
1891 entity_id: usize,
1892 subscription_id: usize,
1893 callback: SubscriptionCallback,
1894 ) {
1895 match self
1896 .subscriptions
1897 .lock()
1898 .entry(entity_id)
1899 .or_default()
1900 .entry(subscription_id)
1901 {
1902 btree_map::Entry::Vacant(entry) => {
1903 entry.insert(Some(callback));
1904 }
1905 // Subscription was dropped before effect was processed
1906 btree_map::Entry::Occupied(entry) => {
1907 debug_assert!(entry.get().is_none());
1908 entry.remove();
1909 }
1910 }
1911 }
1912
1913 fn emit_event(&mut self, entity_id: usize, payload: Box<dyn Any>) {
1914 let callbacks = self.subscriptions.lock().remove(&entity_id);
1915 if let Some(callbacks) = callbacks {
1916 for (id, callback) in callbacks {
1917 if let Some(mut callback) = callback {
1918 let alive = callback(payload.as_ref(), self);
1919 if alive {
1920 match self
1921 .subscriptions
1922 .lock()
1923 .entry(entity_id)
1924 .or_default()
1925 .entry(id)
1926 {
1927 btree_map::Entry::Vacant(entry) => {
1928 entry.insert(Some(callback));
1929 }
1930 btree_map::Entry::Occupied(entry) => {
1931 entry.remove();
1932 }
1933 }
1934 }
1935 }
1936 }
1937 }
1938 }
1939
1940 fn handle_global_subscription_effect(
1941 &mut self,
1942 type_id: TypeId,
1943 subscription_id: usize,
1944 callback: GlobalSubscriptionCallback,
1945 ) {
1946 match self
1947 .global_subscriptions
1948 .lock()
1949 .entry(type_id)
1950 .or_default()
1951 .entry(subscription_id)
1952 {
1953 btree_map::Entry::Vacant(entry) => {
1954 entry.insert(Some(callback));
1955 }
1956 // Subscription was dropped before effect was processed
1957 btree_map::Entry::Occupied(entry) => {
1958 debug_assert!(entry.get().is_none());
1959 entry.remove();
1960 }
1961 }
1962 }
1963
1964 fn emit_global_event(&mut self, payload: Box<dyn Any>) {
1965 let type_id = (&*payload).type_id();
1966 let callbacks = self.global_subscriptions.lock().remove(&type_id);
1967 if let Some(callbacks) = callbacks {
1968 for (id, callback) in callbacks {
1969 if let Some(mut callback) = callback {
1970 callback(payload.as_ref(), self);
1971 match self
1972 .global_subscriptions
1973 .lock()
1974 .entry(type_id)
1975 .or_default()
1976 .entry(id)
1977 {
1978 btree_map::Entry::Vacant(entry) => {
1979 entry.insert(Some(callback));
1980 }
1981 btree_map::Entry::Occupied(entry) => {
1982 entry.remove();
1983 }
1984 }
1985 }
1986 }
1987 }
1988 }
1989
1990 fn handle_observation_effect(
1991 &mut self,
1992 entity_id: usize,
1993 subscription_id: usize,
1994 callback: ObservationCallback,
1995 ) {
1996 match self
1997 .observations
1998 .lock()
1999 .entry(entity_id)
2000 .or_default()
2001 .entry(subscription_id)
2002 {
2003 btree_map::Entry::Vacant(entry) => {
2004 entry.insert(Some(callback));
2005 }
2006 // Observation was dropped before effect was processed
2007 btree_map::Entry::Occupied(entry) => {
2008 debug_assert!(entry.get().is_none());
2009 entry.remove();
2010 }
2011 }
2012 }
2013
2014 fn notify_model_observers(&mut self, observed_id: usize) {
2015 let callbacks = self.observations.lock().remove(&observed_id);
2016 if let Some(callbacks) = callbacks {
2017 if self.cx.models.contains_key(&observed_id) {
2018 for (id, callback) in callbacks {
2019 if let Some(mut callback) = callback {
2020 let alive = callback(self);
2021 if alive {
2022 match self
2023 .observations
2024 .lock()
2025 .entry(observed_id)
2026 .or_default()
2027 .entry(id)
2028 {
2029 btree_map::Entry::Vacant(entry) => {
2030 entry.insert(Some(callback));
2031 }
2032 btree_map::Entry::Occupied(entry) => {
2033 entry.remove();
2034 }
2035 }
2036 }
2037 }
2038 }
2039 }
2040 }
2041 }
2042
2043 fn notify_view_observers(&mut self, observed_window_id: usize, observed_view_id: usize) {
2044 if let Some(window) = self.cx.windows.get_mut(&observed_window_id) {
2045 window
2046 .invalidation
2047 .get_or_insert_with(Default::default)
2048 .updated
2049 .insert(observed_view_id);
2050 }
2051
2052 let callbacks = self.observations.lock().remove(&observed_view_id);
2053 if let Some(callbacks) = callbacks {
2054 if self
2055 .cx
2056 .views
2057 .contains_key(&(observed_window_id, observed_view_id))
2058 {
2059 for (id, callback) in callbacks {
2060 if let Some(mut callback) = callback {
2061 let alive = callback(self);
2062 if alive {
2063 match self
2064 .observations
2065 .lock()
2066 .entry(observed_view_id)
2067 .or_default()
2068 .entry(id)
2069 {
2070 btree_map::Entry::Vacant(entry) => {
2071 entry.insert(Some(callback));
2072 }
2073 btree_map::Entry::Occupied(entry) => {
2074 entry.remove();
2075 }
2076 }
2077 }
2078 }
2079 }
2080 }
2081 }
2082 }
2083
2084 fn notify_global_observers(&mut self, observed_type_id: TypeId) {
2085 let callbacks = self.global_observations.lock().remove(&observed_type_id);
2086 if let Some(callbacks) = callbacks {
2087 if let Some(global) = self.cx.globals.remove(&observed_type_id) {
2088 for (id, callback) in callbacks {
2089 if let Some(mut callback) = callback {
2090 callback(global.as_ref(), self);
2091 match self
2092 .global_observations
2093 .lock()
2094 .entry(observed_type_id)
2095 .or_default()
2096 .entry(id)
2097 {
2098 collections::btree_map::Entry::Vacant(entry) => {
2099 entry.insert(Some(callback));
2100 }
2101 collections::btree_map::Entry::Occupied(entry) => {
2102 entry.remove();
2103 }
2104 }
2105 }
2106 }
2107 self.cx.globals.insert(observed_type_id, global);
2108 }
2109 }
2110 }
2111
2112 fn notify_release_observers(&mut self, entity_id: usize, entity: &dyn Any) {
2113 let callbacks = self.release_observations.lock().remove(&entity_id);
2114 if let Some(callbacks) = callbacks {
2115 for (_, mut callback) in callbacks {
2116 callback(entity, self);
2117 }
2118 }
2119 }
2120
2121 fn focus(&mut self, window_id: usize, focused_id: Option<usize>) {
2122 if self
2123 .cx
2124 .windows
2125 .get(&window_id)
2126 .map(|w| w.focused_view_id)
2127 .map_or(false, |cur_focused| cur_focused == focused_id)
2128 {
2129 return;
2130 }
2131
2132 self.update(|this| {
2133 let blurred_id = this.cx.windows.get_mut(&window_id).and_then(|window| {
2134 let blurred_id = window.focused_view_id;
2135 window.focused_view_id = focused_id;
2136 blurred_id
2137 });
2138
2139 if let Some(blurred_id) = blurred_id {
2140 if let Some(mut blurred_view) = this.cx.views.remove(&(window_id, blurred_id)) {
2141 blurred_view.on_blur(this, window_id, blurred_id);
2142 this.cx.views.insert((window_id, blurred_id), blurred_view);
2143 }
2144 }
2145
2146 if let Some(focused_id) = focused_id {
2147 if let Some(mut focused_view) = this.cx.views.remove(&(window_id, focused_id)) {
2148 focused_view.on_focus(this, window_id, focused_id);
2149 this.cx.views.insert((window_id, focused_id), focused_view);
2150 }
2151 }
2152 })
2153 }
2154
2155 pub fn spawn<F, Fut, T>(&self, f: F) -> Task<T>
2156 where
2157 F: FnOnce(AsyncAppContext) -> Fut,
2158 Fut: 'static + Future<Output = T>,
2159 T: 'static,
2160 {
2161 let future = f(self.to_async());
2162 let cx = self.to_async();
2163 self.foreground.spawn(async move {
2164 let result = future.await;
2165 cx.0.borrow_mut().flush_effects();
2166 result
2167 })
2168 }
2169
2170 pub fn to_async(&self) -> AsyncAppContext {
2171 AsyncAppContext(self.weak_self.as_ref().unwrap().upgrade().unwrap())
2172 }
2173
2174 pub fn write_to_clipboard(&self, item: ClipboardItem) {
2175 self.cx.platform.write_to_clipboard(item);
2176 }
2177
2178 pub fn read_from_clipboard(&self) -> Option<ClipboardItem> {
2179 self.cx.platform.read_from_clipboard()
2180 }
2181
2182 #[cfg(any(test, feature = "test-support"))]
2183 pub fn leak_detector(&self) -> Arc<Mutex<LeakDetector>> {
2184 self.cx.ref_counts.lock().leak_detector.clone()
2185 }
2186}
2187
2188impl ReadModel for MutableAppContext {
2189 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
2190 if let Some(model) = self.cx.models.get(&handle.model_id) {
2191 model
2192 .as_any()
2193 .downcast_ref()
2194 .expect("downcast is type safe")
2195 } else {
2196 panic!("circular model reference");
2197 }
2198 }
2199}
2200
2201impl UpdateModel for MutableAppContext {
2202 fn update_model<T: Entity, V>(
2203 &mut self,
2204 handle: &ModelHandle<T>,
2205 update: &mut dyn FnMut(&mut T, &mut ModelContext<T>) -> V,
2206 ) -> V {
2207 if let Some(mut model) = self.cx.models.remove(&handle.model_id) {
2208 self.update(|this| {
2209 let mut cx = ModelContext::new(this, handle.model_id);
2210 let result = update(
2211 model
2212 .as_any_mut()
2213 .downcast_mut()
2214 .expect("downcast is type safe"),
2215 &mut cx,
2216 );
2217 this.cx.models.insert(handle.model_id, model);
2218 result
2219 })
2220 } else {
2221 panic!("circular model update");
2222 }
2223 }
2224}
2225
2226impl UpgradeModelHandle for MutableAppContext {
2227 fn upgrade_model_handle<T: Entity>(
2228 &self,
2229 handle: &WeakModelHandle<T>,
2230 ) -> Option<ModelHandle<T>> {
2231 self.cx.upgrade_model_handle(handle)
2232 }
2233
2234 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
2235 self.cx.model_handle_is_upgradable(handle)
2236 }
2237
2238 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
2239 self.cx.upgrade_any_model_handle(handle)
2240 }
2241}
2242
2243impl UpgradeViewHandle for MutableAppContext {
2244 fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
2245 self.cx.upgrade_view_handle(handle)
2246 }
2247
2248 fn upgrade_any_view_handle(&self, handle: &AnyWeakViewHandle) -> Option<AnyViewHandle> {
2249 self.cx.upgrade_any_view_handle(handle)
2250 }
2251}
2252
2253impl ReadView for MutableAppContext {
2254 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
2255 if let Some(view) = self.cx.views.get(&(handle.window_id, handle.view_id)) {
2256 view.as_any().downcast_ref().expect("downcast is type safe")
2257 } else {
2258 panic!("circular view reference");
2259 }
2260 }
2261}
2262
2263impl UpdateView for MutableAppContext {
2264 fn update_view<T, S>(
2265 &mut self,
2266 handle: &ViewHandle<T>,
2267 update: &mut dyn FnMut(&mut T, &mut ViewContext<T>) -> S,
2268 ) -> S
2269 where
2270 T: View,
2271 {
2272 self.update(|this| {
2273 let mut view = this
2274 .cx
2275 .views
2276 .remove(&(handle.window_id, handle.view_id))
2277 .expect("circular view update");
2278
2279 let mut cx = ViewContext::new(this, handle.window_id, handle.view_id);
2280 let result = update(
2281 view.as_any_mut()
2282 .downcast_mut()
2283 .expect("downcast is type safe"),
2284 &mut cx,
2285 );
2286 this.cx
2287 .views
2288 .insert((handle.window_id, handle.view_id), view);
2289 result
2290 })
2291 }
2292}
2293
2294impl AsRef<AppContext> for MutableAppContext {
2295 fn as_ref(&self) -> &AppContext {
2296 &self.cx
2297 }
2298}
2299
2300impl Deref for MutableAppContext {
2301 type Target = AppContext;
2302
2303 fn deref(&self) -> &Self::Target {
2304 &self.cx
2305 }
2306}
2307
2308pub struct AppContext {
2309 models: HashMap<usize, Box<dyn AnyModel>>,
2310 views: HashMap<(usize, usize), Box<dyn AnyView>>,
2311 windows: HashMap<usize, Window>,
2312 globals: HashMap<TypeId, Box<dyn Any>>,
2313 element_states: HashMap<ElementStateId, Box<dyn Any>>,
2314 background: Arc<executor::Background>,
2315 ref_counts: Arc<Mutex<RefCounts>>,
2316 font_cache: Arc<FontCache>,
2317 platform: Arc<dyn Platform>,
2318}
2319
2320impl AppContext {
2321 pub fn root_view_id(&self, window_id: usize) -> Option<usize> {
2322 self.windows
2323 .get(&window_id)
2324 .map(|window| window.root_view.id())
2325 }
2326
2327 pub fn focused_view_id(&self, window_id: usize) -> Option<usize> {
2328 self.windows
2329 .get(&window_id)
2330 .and_then(|window| window.focused_view_id)
2331 }
2332
2333 pub fn background(&self) -> &Arc<executor::Background> {
2334 &self.background
2335 }
2336
2337 pub fn font_cache(&self) -> &Arc<FontCache> {
2338 &self.font_cache
2339 }
2340
2341 pub fn platform(&self) -> &Arc<dyn Platform> {
2342 &self.platform
2343 }
2344
2345 pub fn has_global<T: 'static>(&self) -> bool {
2346 self.globals.contains_key(&TypeId::of::<T>())
2347 }
2348
2349 pub fn global<T: 'static>(&self) -> &T {
2350 self.globals
2351 .get(&TypeId::of::<T>())
2352 .expect("no app state has been added for this type")
2353 .downcast_ref()
2354 .unwrap()
2355 }
2356}
2357
2358impl ReadModel for AppContext {
2359 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
2360 if let Some(model) = self.models.get(&handle.model_id) {
2361 model
2362 .as_any()
2363 .downcast_ref()
2364 .expect("downcast should be type safe")
2365 } else {
2366 panic!("circular model reference");
2367 }
2368 }
2369}
2370
2371impl UpgradeModelHandle for AppContext {
2372 fn upgrade_model_handle<T: Entity>(
2373 &self,
2374 handle: &WeakModelHandle<T>,
2375 ) -> Option<ModelHandle<T>> {
2376 if self.models.contains_key(&handle.model_id) {
2377 Some(ModelHandle::new(handle.model_id, &self.ref_counts))
2378 } else {
2379 None
2380 }
2381 }
2382
2383 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
2384 self.models.contains_key(&handle.model_id)
2385 }
2386
2387 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
2388 if self.models.contains_key(&handle.model_id) {
2389 Some(AnyModelHandle::new(
2390 handle.model_id,
2391 handle.model_type,
2392 self.ref_counts.clone(),
2393 ))
2394 } else {
2395 None
2396 }
2397 }
2398}
2399
2400impl UpgradeViewHandle for AppContext {
2401 fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
2402 if self.ref_counts.lock().is_entity_alive(handle.view_id) {
2403 Some(ViewHandle::new(
2404 handle.window_id,
2405 handle.view_id,
2406 &self.ref_counts,
2407 ))
2408 } else {
2409 None
2410 }
2411 }
2412
2413 fn upgrade_any_view_handle(&self, handle: &AnyWeakViewHandle) -> Option<AnyViewHandle> {
2414 if self.ref_counts.lock().is_entity_alive(handle.view_id) {
2415 Some(AnyViewHandle::new(
2416 handle.window_id,
2417 handle.view_id,
2418 handle.view_type,
2419 self.ref_counts.clone(),
2420 ))
2421 } else {
2422 None
2423 }
2424 }
2425}
2426
2427impl ReadView for AppContext {
2428 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
2429 if let Some(view) = self.views.get(&(handle.window_id, handle.view_id)) {
2430 view.as_any()
2431 .downcast_ref()
2432 .expect("downcast should be type safe")
2433 } else {
2434 panic!("circular view reference");
2435 }
2436 }
2437}
2438
2439struct Window {
2440 root_view: AnyViewHandle,
2441 focused_view_id: Option<usize>,
2442 invalidation: Option<WindowInvalidation>,
2443}
2444
2445#[derive(Default, Clone)]
2446pub struct WindowInvalidation {
2447 pub updated: HashSet<usize>,
2448 pub removed: Vec<usize>,
2449}
2450
2451pub enum Effect {
2452 Subscription {
2453 entity_id: usize,
2454 subscription_id: usize,
2455 callback: SubscriptionCallback,
2456 },
2457 Event {
2458 entity_id: usize,
2459 payload: Box<dyn Any>,
2460 },
2461 GlobalSubscription {
2462 type_id: TypeId,
2463 subscription_id: usize,
2464 callback: GlobalSubscriptionCallback,
2465 },
2466 GlobalEvent {
2467 payload: Box<dyn Any>,
2468 },
2469 Observation {
2470 entity_id: usize,
2471 subscription_id: usize,
2472 callback: ObservationCallback,
2473 },
2474 ModelNotification {
2475 model_id: usize,
2476 },
2477 ViewNotification {
2478 window_id: usize,
2479 view_id: usize,
2480 },
2481 Deferred {
2482 callback: Box<dyn FnOnce(&mut MutableAppContext)>,
2483 after_window_update: bool,
2484 },
2485 GlobalNotification {
2486 type_id: TypeId,
2487 },
2488 ModelRelease {
2489 model_id: usize,
2490 model: Box<dyn AnyModel>,
2491 },
2492 ViewRelease {
2493 view_id: usize,
2494 view: Box<dyn AnyView>,
2495 },
2496 Focus {
2497 window_id: usize,
2498 view_id: Option<usize>,
2499 },
2500 ResizeWindow {
2501 window_id: usize,
2502 },
2503 RefreshWindows,
2504}
2505
2506impl Debug for Effect {
2507 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
2508 match self {
2509 Effect::Subscription {
2510 entity_id,
2511 subscription_id,
2512 ..
2513 } => f
2514 .debug_struct("Effect::Subscribe")
2515 .field("entity_id", entity_id)
2516 .field("subscription_id", subscription_id)
2517 .finish(),
2518 Effect::Event { entity_id, .. } => f
2519 .debug_struct("Effect::Event")
2520 .field("entity_id", entity_id)
2521 .finish(),
2522 Effect::GlobalSubscription {
2523 type_id,
2524 subscription_id,
2525 ..
2526 } => f
2527 .debug_struct("Effect::Subscribe")
2528 .field("type_id", type_id)
2529 .field("subscription_id", subscription_id)
2530 .finish(),
2531 Effect::GlobalEvent { payload, .. } => f
2532 .debug_struct("Effect::GlobalEvent")
2533 .field("type_id", &(&*payload).type_id())
2534 .finish(),
2535 Effect::Observation {
2536 entity_id,
2537 subscription_id,
2538 ..
2539 } => f
2540 .debug_struct("Effect::Observation")
2541 .field("entity_id", entity_id)
2542 .field("subscription_id", subscription_id)
2543 .finish(),
2544 Effect::ModelNotification { model_id } => f
2545 .debug_struct("Effect::ModelNotification")
2546 .field("model_id", model_id)
2547 .finish(),
2548 Effect::ViewNotification { window_id, view_id } => f
2549 .debug_struct("Effect::ViewNotification")
2550 .field("window_id", window_id)
2551 .field("view_id", view_id)
2552 .finish(),
2553 Effect::GlobalNotification { type_id } => f
2554 .debug_struct("Effect::GlobalNotification")
2555 .field("type_id", type_id)
2556 .finish(),
2557 Effect::Deferred { .. } => f.debug_struct("Effect::Deferred").finish(),
2558 Effect::ModelRelease { model_id, .. } => f
2559 .debug_struct("Effect::ModelRelease")
2560 .field("model_id", model_id)
2561 .finish(),
2562 Effect::ViewRelease { view_id, .. } => f
2563 .debug_struct("Effect::ViewRelease")
2564 .field("view_id", view_id)
2565 .finish(),
2566 Effect::Focus { window_id, view_id } => f
2567 .debug_struct("Effect::Focus")
2568 .field("window_id", window_id)
2569 .field("view_id", view_id)
2570 .finish(),
2571 Effect::ResizeWindow { window_id } => f
2572 .debug_struct("Effect::RefreshWindow")
2573 .field("window_id", window_id)
2574 .finish(),
2575 Effect::RefreshWindows => f.debug_struct("Effect::FullViewRefresh").finish(),
2576 }
2577 }
2578}
2579
2580pub trait AnyModel {
2581 fn as_any(&self) -> &dyn Any;
2582 fn as_any_mut(&mut self) -> &mut dyn Any;
2583 fn release(&mut self, cx: &mut MutableAppContext);
2584 fn app_will_quit(
2585 &mut self,
2586 cx: &mut MutableAppContext,
2587 ) -> Option<Pin<Box<dyn 'static + Future<Output = ()>>>>;
2588}
2589
2590impl<T> AnyModel for T
2591where
2592 T: Entity,
2593{
2594 fn as_any(&self) -> &dyn Any {
2595 self
2596 }
2597
2598 fn as_any_mut(&mut self) -> &mut dyn Any {
2599 self
2600 }
2601
2602 fn release(&mut self, cx: &mut MutableAppContext) {
2603 self.release(cx);
2604 }
2605
2606 fn app_will_quit(
2607 &mut self,
2608 cx: &mut MutableAppContext,
2609 ) -> Option<Pin<Box<dyn 'static + Future<Output = ()>>>> {
2610 self.app_will_quit(cx)
2611 }
2612}
2613
2614pub trait AnyView {
2615 fn as_any(&self) -> &dyn Any;
2616 fn as_any_mut(&mut self) -> &mut dyn Any;
2617 fn release(&mut self, cx: &mut MutableAppContext);
2618 fn app_will_quit(
2619 &mut self,
2620 cx: &mut MutableAppContext,
2621 ) -> Option<Pin<Box<dyn 'static + Future<Output = ()>>>>;
2622 fn ui_name(&self) -> &'static str;
2623 fn render<'a>(
2624 &mut self,
2625 window_id: usize,
2626 view_id: usize,
2627 titlebar_height: f32,
2628 refreshing: bool,
2629 cx: &mut MutableAppContext,
2630 ) -> ElementBox;
2631 fn on_focus(&mut self, cx: &mut MutableAppContext, window_id: usize, view_id: usize);
2632 fn on_blur(&mut self, cx: &mut MutableAppContext, window_id: usize, view_id: usize);
2633 fn keymap_context(&self, cx: &AppContext) -> keymap::Context;
2634}
2635
2636impl<T> AnyView for T
2637where
2638 T: View,
2639{
2640 fn as_any(&self) -> &dyn Any {
2641 self
2642 }
2643
2644 fn as_any_mut(&mut self) -> &mut dyn Any {
2645 self
2646 }
2647
2648 fn release(&mut self, cx: &mut MutableAppContext) {
2649 self.release(cx);
2650 }
2651
2652 fn app_will_quit(
2653 &mut self,
2654 cx: &mut MutableAppContext,
2655 ) -> Option<Pin<Box<dyn 'static + Future<Output = ()>>>> {
2656 self.app_will_quit(cx)
2657 }
2658
2659 fn ui_name(&self) -> &'static str {
2660 T::ui_name()
2661 }
2662
2663 fn render<'a>(
2664 &mut self,
2665 window_id: usize,
2666 view_id: usize,
2667 titlebar_height: f32,
2668 refreshing: bool,
2669 cx: &mut MutableAppContext,
2670 ) -> ElementBox {
2671 View::render(
2672 self,
2673 &mut RenderContext {
2674 window_id,
2675 view_id,
2676 app: cx,
2677 view_type: PhantomData::<T>,
2678 titlebar_height,
2679 refreshing,
2680 },
2681 )
2682 }
2683
2684 fn on_focus(&mut self, cx: &mut MutableAppContext, window_id: usize, view_id: usize) {
2685 let mut cx = ViewContext::new(cx, window_id, view_id);
2686 View::on_focus(self, &mut cx);
2687 }
2688
2689 fn on_blur(&mut self, cx: &mut MutableAppContext, window_id: usize, view_id: usize) {
2690 let mut cx = ViewContext::new(cx, window_id, view_id);
2691 View::on_blur(self, &mut cx);
2692 }
2693
2694 fn keymap_context(&self, cx: &AppContext) -> keymap::Context {
2695 View::keymap_context(self, cx)
2696 }
2697}
2698
2699pub struct ModelContext<'a, T: ?Sized> {
2700 app: &'a mut MutableAppContext,
2701 model_id: usize,
2702 model_type: PhantomData<T>,
2703 halt_stream: bool,
2704}
2705
2706impl<'a, T: Entity> ModelContext<'a, T> {
2707 fn new(app: &'a mut MutableAppContext, model_id: usize) -> Self {
2708 Self {
2709 app,
2710 model_id,
2711 model_type: PhantomData,
2712 halt_stream: false,
2713 }
2714 }
2715
2716 pub fn background(&self) -> &Arc<executor::Background> {
2717 &self.app.cx.background
2718 }
2719
2720 pub fn halt_stream(&mut self) {
2721 self.halt_stream = true;
2722 }
2723
2724 pub fn model_id(&self) -> usize {
2725 self.model_id
2726 }
2727
2728 pub fn add_model<S, F>(&mut self, build_model: F) -> ModelHandle<S>
2729 where
2730 S: Entity,
2731 F: FnOnce(&mut ModelContext<S>) -> S,
2732 {
2733 self.app.add_model(build_model)
2734 }
2735
2736 pub fn defer(&mut self, callback: impl 'static + FnOnce(&mut T, &mut ModelContext<T>)) {
2737 let handle = self.handle();
2738 self.app.defer(move |cx| {
2739 handle.update(cx, |model, cx| {
2740 callback(model, cx);
2741 })
2742 })
2743 }
2744
2745 pub fn emit(&mut self, payload: T::Event) {
2746 self.app.pending_effects.push_back(Effect::Event {
2747 entity_id: self.model_id,
2748 payload: Box::new(payload),
2749 });
2750 }
2751
2752 pub fn notify(&mut self) {
2753 self.app.notify_model(self.model_id);
2754 }
2755
2756 pub fn subscribe<S: Entity, F>(
2757 &mut self,
2758 handle: &ModelHandle<S>,
2759 mut callback: F,
2760 ) -> Subscription
2761 where
2762 S::Event: 'static,
2763 F: 'static + FnMut(&mut T, ModelHandle<S>, &S::Event, &mut ModelContext<T>),
2764 {
2765 let subscriber = self.weak_handle();
2766 self.app
2767 .subscribe_internal(handle, move |emitter, event, cx| {
2768 if let Some(subscriber) = subscriber.upgrade(cx) {
2769 subscriber.update(cx, |subscriber, cx| {
2770 callback(subscriber, emitter, event, cx);
2771 });
2772 true
2773 } else {
2774 false
2775 }
2776 })
2777 }
2778
2779 pub fn observe<S, F>(&mut self, handle: &ModelHandle<S>, mut callback: F) -> Subscription
2780 where
2781 S: Entity,
2782 F: 'static + FnMut(&mut T, ModelHandle<S>, &mut ModelContext<T>),
2783 {
2784 let observer = self.weak_handle();
2785 self.app.observe_internal(handle, move |observed, cx| {
2786 if let Some(observer) = observer.upgrade(cx) {
2787 observer.update(cx, |observer, cx| {
2788 callback(observer, observed, cx);
2789 });
2790 true
2791 } else {
2792 false
2793 }
2794 })
2795 }
2796
2797 pub fn observe_release<S, F>(
2798 &mut self,
2799 handle: &ModelHandle<S>,
2800 mut callback: F,
2801 ) -> Subscription
2802 where
2803 S: Entity,
2804 F: 'static + FnMut(&mut T, &S, &mut ModelContext<T>),
2805 {
2806 let observer = self.weak_handle();
2807 self.app.observe_release(handle, move |released, cx| {
2808 if let Some(observer) = observer.upgrade(cx) {
2809 observer.update(cx, |observer, cx| {
2810 callback(observer, released, cx);
2811 });
2812 }
2813 })
2814 }
2815
2816 pub fn handle(&self) -> ModelHandle<T> {
2817 ModelHandle::new(self.model_id, &self.app.cx.ref_counts)
2818 }
2819
2820 pub fn weak_handle(&self) -> WeakModelHandle<T> {
2821 WeakModelHandle::new(self.model_id)
2822 }
2823
2824 pub fn spawn<F, Fut, S>(&self, f: F) -> Task<S>
2825 where
2826 F: FnOnce(ModelHandle<T>, AsyncAppContext) -> Fut,
2827 Fut: 'static + Future<Output = S>,
2828 S: 'static,
2829 {
2830 let handle = self.handle();
2831 self.app.spawn(|cx| f(handle, cx))
2832 }
2833
2834 pub fn spawn_weak<F, Fut, S>(&self, f: F) -> Task<S>
2835 where
2836 F: FnOnce(WeakModelHandle<T>, AsyncAppContext) -> Fut,
2837 Fut: 'static + Future<Output = S>,
2838 S: 'static,
2839 {
2840 let handle = self.weak_handle();
2841 self.app.spawn(|cx| f(handle, cx))
2842 }
2843}
2844
2845impl<M> AsRef<AppContext> for ModelContext<'_, M> {
2846 fn as_ref(&self) -> &AppContext {
2847 &self.app.cx
2848 }
2849}
2850
2851impl<M> AsMut<MutableAppContext> for ModelContext<'_, M> {
2852 fn as_mut(&mut self) -> &mut MutableAppContext {
2853 self.app
2854 }
2855}
2856
2857impl<M> ReadModel for ModelContext<'_, M> {
2858 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
2859 self.app.read_model(handle)
2860 }
2861}
2862
2863impl<M> UpdateModel for ModelContext<'_, M> {
2864 fn update_model<T: Entity, V>(
2865 &mut self,
2866 handle: &ModelHandle<T>,
2867 update: &mut dyn FnMut(&mut T, &mut ModelContext<T>) -> V,
2868 ) -> V {
2869 self.app.update_model(handle, update)
2870 }
2871}
2872
2873impl<M> UpgradeModelHandle for ModelContext<'_, M> {
2874 fn upgrade_model_handle<T: Entity>(
2875 &self,
2876 handle: &WeakModelHandle<T>,
2877 ) -> Option<ModelHandle<T>> {
2878 self.cx.upgrade_model_handle(handle)
2879 }
2880
2881 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
2882 self.cx.model_handle_is_upgradable(handle)
2883 }
2884
2885 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
2886 self.cx.upgrade_any_model_handle(handle)
2887 }
2888}
2889
2890impl<M> Deref for ModelContext<'_, M> {
2891 type Target = MutableAppContext;
2892
2893 fn deref(&self) -> &Self::Target {
2894 &self.app
2895 }
2896}
2897
2898impl<M> DerefMut for ModelContext<'_, M> {
2899 fn deref_mut(&mut self) -> &mut Self::Target {
2900 &mut self.app
2901 }
2902}
2903
2904pub struct ViewContext<'a, T: ?Sized> {
2905 app: &'a mut MutableAppContext,
2906 window_id: usize,
2907 view_id: usize,
2908 view_type: PhantomData<T>,
2909}
2910
2911impl<'a, T: View> ViewContext<'a, T> {
2912 fn new(app: &'a mut MutableAppContext, window_id: usize, view_id: usize) -> Self {
2913 Self {
2914 app,
2915 window_id,
2916 view_id,
2917 view_type: PhantomData,
2918 }
2919 }
2920
2921 pub fn handle(&self) -> ViewHandle<T> {
2922 ViewHandle::new(self.window_id, self.view_id, &self.app.cx.ref_counts)
2923 }
2924
2925 pub fn weak_handle(&self) -> WeakViewHandle<T> {
2926 WeakViewHandle::new(self.window_id, self.view_id)
2927 }
2928
2929 pub fn window_id(&self) -> usize {
2930 self.window_id
2931 }
2932
2933 pub fn view_id(&self) -> usize {
2934 self.view_id
2935 }
2936
2937 pub fn foreground(&self) -> &Rc<executor::Foreground> {
2938 self.app.foreground()
2939 }
2940
2941 pub fn background_executor(&self) -> &Arc<executor::Background> {
2942 &self.app.cx.background
2943 }
2944
2945 pub fn platform(&self) -> Arc<dyn Platform> {
2946 self.app.platform()
2947 }
2948
2949 pub fn prompt(
2950 &self,
2951 level: PromptLevel,
2952 msg: &str,
2953 answers: &[&str],
2954 ) -> oneshot::Receiver<usize> {
2955 self.app.prompt(self.window_id, level, msg, answers)
2956 }
2957
2958 pub fn prompt_for_paths(
2959 &self,
2960 options: PathPromptOptions,
2961 ) -> oneshot::Receiver<Option<Vec<PathBuf>>> {
2962 self.app.prompt_for_paths(options)
2963 }
2964
2965 pub fn prompt_for_new_path(&self, directory: &Path) -> oneshot::Receiver<Option<PathBuf>> {
2966 self.app.prompt_for_new_path(directory)
2967 }
2968
2969 pub fn debug_elements(&self) -> crate::json::Value {
2970 self.app.debug_elements(self.window_id).unwrap()
2971 }
2972
2973 pub fn focus<S>(&mut self, handle: S)
2974 where
2975 S: Into<AnyViewHandle>,
2976 {
2977 let handle = handle.into();
2978 self.app.pending_effects.push_back(Effect::Focus {
2979 window_id: handle.window_id,
2980 view_id: Some(handle.view_id),
2981 });
2982 }
2983
2984 pub fn focus_self(&mut self) {
2985 self.app.pending_effects.push_back(Effect::Focus {
2986 window_id: self.window_id,
2987 view_id: Some(self.view_id),
2988 });
2989 }
2990
2991 pub fn blur(&mut self) {
2992 self.app.pending_effects.push_back(Effect::Focus {
2993 window_id: self.window_id,
2994 view_id: None,
2995 });
2996 }
2997
2998 pub fn add_model<S, F>(&mut self, build_model: F) -> ModelHandle<S>
2999 where
3000 S: Entity,
3001 F: FnOnce(&mut ModelContext<S>) -> S,
3002 {
3003 self.app.add_model(build_model)
3004 }
3005
3006 pub fn add_view<S, F>(&mut self, build_view: F) -> ViewHandle<S>
3007 where
3008 S: View,
3009 F: FnOnce(&mut ViewContext<S>) -> S,
3010 {
3011 self.app.add_view(self.window_id, build_view)
3012 }
3013
3014 pub fn add_option_view<S, F>(&mut self, build_view: F) -> Option<ViewHandle<S>>
3015 where
3016 S: View,
3017 F: FnOnce(&mut ViewContext<S>) -> Option<S>,
3018 {
3019 self.app.add_option_view(self.window_id, build_view)
3020 }
3021
3022 pub fn subscribe<E, H, F>(&mut self, handle: &H, mut callback: F) -> Subscription
3023 where
3024 E: Entity,
3025 E::Event: 'static,
3026 H: Handle<E>,
3027 F: 'static + FnMut(&mut T, H, &E::Event, &mut ViewContext<T>),
3028 {
3029 let subscriber = self.weak_handle();
3030 self.app
3031 .subscribe_internal(handle, move |emitter, event, cx| {
3032 if let Some(subscriber) = subscriber.upgrade(cx) {
3033 subscriber.update(cx, |subscriber, cx| {
3034 callback(subscriber, emitter, event, cx);
3035 });
3036 true
3037 } else {
3038 false
3039 }
3040 })
3041 }
3042
3043 pub fn observe<E, F, H>(&mut self, handle: &H, mut callback: F) -> Subscription
3044 where
3045 E: Entity,
3046 H: Handle<E>,
3047 F: 'static + FnMut(&mut T, H, &mut ViewContext<T>),
3048 {
3049 let observer = self.weak_handle();
3050 self.app.observe_internal(handle, move |observed, cx| {
3051 if let Some(observer) = observer.upgrade(cx) {
3052 observer.update(cx, |observer, cx| {
3053 callback(observer, observed, cx);
3054 });
3055 true
3056 } else {
3057 false
3058 }
3059 })
3060 }
3061
3062 pub fn observe_release<E, F, H>(&mut self, handle: &H, mut callback: F) -> Subscription
3063 where
3064 E: Entity,
3065 H: Handle<E>,
3066 F: 'static + FnMut(&mut T, &E, &mut ViewContext<T>),
3067 {
3068 let observer = self.weak_handle();
3069 self.app.observe_release(handle, move |released, cx| {
3070 if let Some(observer) = observer.upgrade(cx) {
3071 observer.update(cx, |observer, cx| {
3072 callback(observer, released, cx);
3073 });
3074 }
3075 })
3076 }
3077
3078 pub fn emit(&mut self, payload: T::Event) {
3079 self.app.pending_effects.push_back(Effect::Event {
3080 entity_id: self.view_id,
3081 payload: Box::new(payload),
3082 });
3083 }
3084
3085 pub fn notify(&mut self) {
3086 self.app.notify_view(self.window_id, self.view_id);
3087 }
3088
3089 pub fn defer(&mut self, callback: impl 'static + FnOnce(&mut T, &mut ViewContext<T>)) {
3090 let handle = self.handle();
3091 self.app.defer(move |cx| {
3092 handle.update(cx, |view, cx| {
3093 callback(view, cx);
3094 })
3095 })
3096 }
3097
3098 pub fn after_window_update(
3099 &mut self,
3100 callback: impl 'static + FnOnce(&mut T, &mut ViewContext<T>),
3101 ) {
3102 let handle = self.handle();
3103 self.app.after_window_update(move |cx| {
3104 handle.update(cx, |view, cx| {
3105 callback(view, cx);
3106 })
3107 })
3108 }
3109
3110 pub fn propagate_action(&mut self) {
3111 self.app.halt_action_dispatch = false;
3112 }
3113
3114 pub fn spawn<F, Fut, S>(&self, f: F) -> Task<S>
3115 where
3116 F: FnOnce(ViewHandle<T>, AsyncAppContext) -> Fut,
3117 Fut: 'static + Future<Output = S>,
3118 S: 'static,
3119 {
3120 let handle = self.handle();
3121 self.app.spawn(|cx| f(handle, cx))
3122 }
3123
3124 pub fn spawn_weak<F, Fut, S>(&self, f: F) -> Task<S>
3125 where
3126 F: FnOnce(WeakViewHandle<T>, AsyncAppContext) -> Fut,
3127 Fut: 'static + Future<Output = S>,
3128 S: 'static,
3129 {
3130 let handle = self.weak_handle();
3131 self.app.spawn(|cx| f(handle, cx))
3132 }
3133}
3134
3135pub struct RenderContext<'a, T: View> {
3136 pub app: &'a mut MutableAppContext,
3137 pub titlebar_height: f32,
3138 pub refreshing: bool,
3139 window_id: usize,
3140 view_id: usize,
3141 view_type: PhantomData<T>,
3142}
3143
3144impl<'a, T: View> RenderContext<'a, T> {
3145 pub fn handle(&self) -> WeakViewHandle<T> {
3146 WeakViewHandle::new(self.window_id, self.view_id)
3147 }
3148
3149 pub fn view_id(&self) -> usize {
3150 self.view_id
3151 }
3152}
3153
3154impl AsRef<AppContext> for &AppContext {
3155 fn as_ref(&self) -> &AppContext {
3156 self
3157 }
3158}
3159
3160impl<V: View> Deref for RenderContext<'_, V> {
3161 type Target = MutableAppContext;
3162
3163 fn deref(&self) -> &Self::Target {
3164 self.app
3165 }
3166}
3167
3168impl<V: View> DerefMut for RenderContext<'_, V> {
3169 fn deref_mut(&mut self) -> &mut Self::Target {
3170 self.app
3171 }
3172}
3173
3174impl<V: View> ReadModel for RenderContext<'_, V> {
3175 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
3176 self.app.read_model(handle)
3177 }
3178}
3179
3180impl<V: View> UpdateModel for RenderContext<'_, V> {
3181 fn update_model<T: Entity, O>(
3182 &mut self,
3183 handle: &ModelHandle<T>,
3184 update: &mut dyn FnMut(&mut T, &mut ModelContext<T>) -> O,
3185 ) -> O {
3186 self.app.update_model(handle, update)
3187 }
3188}
3189
3190impl<V: View> ReadView for RenderContext<'_, V> {
3191 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
3192 self.app.read_view(handle)
3193 }
3194}
3195
3196impl<V: View> ElementStateContext for RenderContext<'_, V> {
3197 fn current_view_id(&self) -> usize {
3198 self.view_id
3199 }
3200}
3201
3202impl<M> AsRef<AppContext> for ViewContext<'_, M> {
3203 fn as_ref(&self) -> &AppContext {
3204 &self.app.cx
3205 }
3206}
3207
3208impl<M> Deref for ViewContext<'_, M> {
3209 type Target = MutableAppContext;
3210
3211 fn deref(&self) -> &Self::Target {
3212 &self.app
3213 }
3214}
3215
3216impl<M> DerefMut for ViewContext<'_, M> {
3217 fn deref_mut(&mut self) -> &mut Self::Target {
3218 &mut self.app
3219 }
3220}
3221
3222impl<M> AsMut<MutableAppContext> for ViewContext<'_, M> {
3223 fn as_mut(&mut self) -> &mut MutableAppContext {
3224 self.app
3225 }
3226}
3227
3228impl<V> ReadModel for ViewContext<'_, V> {
3229 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
3230 self.app.read_model(handle)
3231 }
3232}
3233
3234impl<V> UpgradeModelHandle for ViewContext<'_, V> {
3235 fn upgrade_model_handle<T: Entity>(
3236 &self,
3237 handle: &WeakModelHandle<T>,
3238 ) -> Option<ModelHandle<T>> {
3239 self.cx.upgrade_model_handle(handle)
3240 }
3241
3242 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
3243 self.cx.model_handle_is_upgradable(handle)
3244 }
3245
3246 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
3247 self.cx.upgrade_any_model_handle(handle)
3248 }
3249}
3250
3251impl<V> UpgradeViewHandle for ViewContext<'_, V> {
3252 fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
3253 self.cx.upgrade_view_handle(handle)
3254 }
3255
3256 fn upgrade_any_view_handle(&self, handle: &AnyWeakViewHandle) -> Option<AnyViewHandle> {
3257 self.cx.upgrade_any_view_handle(handle)
3258 }
3259}
3260
3261impl<V: View> UpdateModel for ViewContext<'_, V> {
3262 fn update_model<T: Entity, O>(
3263 &mut self,
3264 handle: &ModelHandle<T>,
3265 update: &mut dyn FnMut(&mut T, &mut ModelContext<T>) -> O,
3266 ) -> O {
3267 self.app.update_model(handle, update)
3268 }
3269}
3270
3271impl<V: View> ReadView for ViewContext<'_, V> {
3272 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
3273 self.app.read_view(handle)
3274 }
3275}
3276
3277impl<V: View> UpdateView for ViewContext<'_, V> {
3278 fn update_view<T, S>(
3279 &mut self,
3280 handle: &ViewHandle<T>,
3281 update: &mut dyn FnMut(&mut T, &mut ViewContext<T>) -> S,
3282 ) -> S
3283 where
3284 T: View,
3285 {
3286 self.app.update_view(handle, update)
3287 }
3288}
3289
3290impl<V: View> ElementStateContext for ViewContext<'_, V> {
3291 fn current_view_id(&self) -> usize {
3292 self.view_id
3293 }
3294}
3295
3296pub trait Handle<T> {
3297 type Weak: 'static;
3298 fn id(&self) -> usize;
3299 fn location(&self) -> EntityLocation;
3300 fn downgrade(&self) -> Self::Weak;
3301 fn upgrade_from(weak: &Self::Weak, cx: &AppContext) -> Option<Self>
3302 where
3303 Self: Sized;
3304}
3305
3306#[derive(Clone, Copy, Debug, Eq, PartialEq, Hash)]
3307pub enum EntityLocation {
3308 Model(usize),
3309 View(usize, usize),
3310}
3311
3312pub struct ModelHandle<T: Entity> {
3313 model_id: usize,
3314 model_type: PhantomData<T>,
3315 ref_counts: Arc<Mutex<RefCounts>>,
3316
3317 #[cfg(any(test, feature = "test-support"))]
3318 handle_id: usize,
3319}
3320
3321impl<T: Entity> ModelHandle<T> {
3322 fn new(model_id: usize, ref_counts: &Arc<Mutex<RefCounts>>) -> Self {
3323 ref_counts.lock().inc_model(model_id);
3324
3325 #[cfg(any(test, feature = "test-support"))]
3326 let handle_id = ref_counts
3327 .lock()
3328 .leak_detector
3329 .lock()
3330 .handle_created(Some(type_name::<T>()), model_id);
3331
3332 Self {
3333 model_id,
3334 model_type: PhantomData,
3335 ref_counts: ref_counts.clone(),
3336
3337 #[cfg(any(test, feature = "test-support"))]
3338 handle_id,
3339 }
3340 }
3341
3342 pub fn downgrade(&self) -> WeakModelHandle<T> {
3343 WeakModelHandle::new(self.model_id)
3344 }
3345
3346 pub fn id(&self) -> usize {
3347 self.model_id
3348 }
3349
3350 pub fn read<'a, C: ReadModel>(&self, cx: &'a C) -> &'a T {
3351 cx.read_model(self)
3352 }
3353
3354 pub fn read_with<'a, C, F, S>(&self, cx: &C, read: F) -> S
3355 where
3356 C: ReadModelWith,
3357 F: FnOnce(&T, &AppContext) -> S,
3358 {
3359 let mut read = Some(read);
3360 cx.read_model_with(self, &mut |model, cx| {
3361 let read = read.take().unwrap();
3362 read(model, cx)
3363 })
3364 }
3365
3366 pub fn update<C, F, S>(&self, cx: &mut C, update: F) -> S
3367 where
3368 C: UpdateModel,
3369 F: FnOnce(&mut T, &mut ModelContext<T>) -> S,
3370 {
3371 let mut update = Some(update);
3372 cx.update_model(self, &mut |model, cx| {
3373 let update = update.take().unwrap();
3374 update(model, cx)
3375 })
3376 }
3377
3378 #[cfg(any(test, feature = "test-support"))]
3379 pub fn next_notification(&self, cx: &TestAppContext) -> impl Future<Output = ()> {
3380 use postage::prelude::{Sink as _, Stream as _};
3381
3382 let (mut tx, mut rx) = postage::mpsc::channel(1);
3383 let mut cx = cx.cx.borrow_mut();
3384 let subscription = cx.observe(self, move |_, _| {
3385 tx.try_send(()).ok();
3386 });
3387
3388 let duration = if std::env::var("CI").is_ok() {
3389 Duration::from_secs(5)
3390 } else {
3391 Duration::from_secs(1)
3392 };
3393
3394 async move {
3395 let notification = crate::util::timeout(duration, rx.recv())
3396 .await
3397 .expect("next notification timed out");
3398 drop(subscription);
3399 notification.expect("model dropped while test was waiting for its next notification")
3400 }
3401 }
3402
3403 #[cfg(any(test, feature = "test-support"))]
3404 pub fn next_event(&self, cx: &TestAppContext) -> impl Future<Output = T::Event>
3405 where
3406 T::Event: Clone,
3407 {
3408 use postage::prelude::{Sink as _, Stream as _};
3409
3410 let (mut tx, mut rx) = postage::mpsc::channel(1);
3411 let mut cx = cx.cx.borrow_mut();
3412 let subscription = cx.subscribe(self, move |_, event, _| {
3413 tx.blocking_send(event.clone()).ok();
3414 });
3415
3416 let duration = if std::env::var("CI").is_ok() {
3417 Duration::from_secs(5)
3418 } else {
3419 Duration::from_secs(1)
3420 };
3421
3422 async move {
3423 let event = crate::util::timeout(duration, rx.recv())
3424 .await
3425 .expect("next event timed out");
3426 drop(subscription);
3427 event.expect("model dropped while test was waiting for its next event")
3428 }
3429 }
3430
3431 #[cfg(any(test, feature = "test-support"))]
3432 pub fn condition(
3433 &self,
3434 cx: &TestAppContext,
3435 mut predicate: impl FnMut(&T, &AppContext) -> bool,
3436 ) -> impl Future<Output = ()> {
3437 use postage::prelude::{Sink as _, Stream as _};
3438
3439 let (tx, mut rx) = postage::mpsc::channel(1024);
3440
3441 let mut cx = cx.cx.borrow_mut();
3442 let subscriptions = (
3443 cx.observe(self, {
3444 let mut tx = tx.clone();
3445 move |_, _| {
3446 tx.blocking_send(()).ok();
3447 }
3448 }),
3449 cx.subscribe(self, {
3450 let mut tx = tx.clone();
3451 move |_, _, _| {
3452 tx.blocking_send(()).ok();
3453 }
3454 }),
3455 );
3456
3457 let cx = cx.weak_self.as_ref().unwrap().upgrade().unwrap();
3458 let handle = self.downgrade();
3459 let duration = if std::env::var("CI").is_ok() {
3460 Duration::from_secs(5)
3461 } else {
3462 Duration::from_secs(1)
3463 };
3464
3465 async move {
3466 crate::util::timeout(duration, async move {
3467 loop {
3468 {
3469 let cx = cx.borrow();
3470 let cx = cx.as_ref();
3471 if predicate(
3472 handle
3473 .upgrade(cx)
3474 .expect("model dropped with pending condition")
3475 .read(cx),
3476 cx,
3477 ) {
3478 break;
3479 }
3480 }
3481
3482 cx.borrow().foreground().start_waiting();
3483 rx.recv()
3484 .await
3485 .expect("model dropped with pending condition");
3486 cx.borrow().foreground().finish_waiting();
3487 }
3488 })
3489 .await
3490 .expect("condition timed out");
3491 drop(subscriptions);
3492 }
3493 }
3494}
3495
3496impl<T: Entity> Clone for ModelHandle<T> {
3497 fn clone(&self) -> Self {
3498 Self::new(self.model_id, &self.ref_counts)
3499 }
3500}
3501
3502impl<T: Entity> PartialEq for ModelHandle<T> {
3503 fn eq(&self, other: &Self) -> bool {
3504 self.model_id == other.model_id
3505 }
3506}
3507
3508impl<T: Entity> Eq for ModelHandle<T> {}
3509
3510impl<T: Entity> PartialEq<WeakModelHandle<T>> for ModelHandle<T> {
3511 fn eq(&self, other: &WeakModelHandle<T>) -> bool {
3512 self.model_id == other.model_id
3513 }
3514}
3515
3516impl<T: Entity> Hash for ModelHandle<T> {
3517 fn hash<H: Hasher>(&self, state: &mut H) {
3518 self.model_id.hash(state);
3519 }
3520}
3521
3522impl<T: Entity> std::borrow::Borrow<usize> for ModelHandle<T> {
3523 fn borrow(&self) -> &usize {
3524 &self.model_id
3525 }
3526}
3527
3528impl<T: Entity> Debug for ModelHandle<T> {
3529 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
3530 f.debug_tuple(&format!("ModelHandle<{}>", type_name::<T>()))
3531 .field(&self.model_id)
3532 .finish()
3533 }
3534}
3535
3536unsafe impl<T: Entity> Send for ModelHandle<T> {}
3537unsafe impl<T: Entity> Sync for ModelHandle<T> {}
3538
3539impl<T: Entity> Drop for ModelHandle<T> {
3540 fn drop(&mut self) {
3541 let mut ref_counts = self.ref_counts.lock();
3542 ref_counts.dec_model(self.model_id);
3543
3544 #[cfg(any(test, feature = "test-support"))]
3545 ref_counts
3546 .leak_detector
3547 .lock()
3548 .handle_dropped(self.model_id, self.handle_id);
3549 }
3550}
3551
3552impl<T: Entity> Handle<T> for ModelHandle<T> {
3553 type Weak = WeakModelHandle<T>;
3554
3555 fn id(&self) -> usize {
3556 self.model_id
3557 }
3558
3559 fn location(&self) -> EntityLocation {
3560 EntityLocation::Model(self.model_id)
3561 }
3562
3563 fn downgrade(&self) -> Self::Weak {
3564 self.downgrade()
3565 }
3566
3567 fn upgrade_from(weak: &Self::Weak, cx: &AppContext) -> Option<Self>
3568 where
3569 Self: Sized,
3570 {
3571 weak.upgrade(cx)
3572 }
3573}
3574
3575pub struct WeakModelHandle<T> {
3576 model_id: usize,
3577 model_type: PhantomData<T>,
3578}
3579
3580unsafe impl<T> Send for WeakModelHandle<T> {}
3581unsafe impl<T> Sync for WeakModelHandle<T> {}
3582
3583impl<T: Entity> WeakModelHandle<T> {
3584 fn new(model_id: usize) -> Self {
3585 Self {
3586 model_id,
3587 model_type: PhantomData,
3588 }
3589 }
3590
3591 pub fn id(&self) -> usize {
3592 self.model_id
3593 }
3594
3595 pub fn is_upgradable(&self, cx: &impl UpgradeModelHandle) -> bool {
3596 cx.model_handle_is_upgradable(self)
3597 }
3598
3599 pub fn upgrade(&self, cx: &impl UpgradeModelHandle) -> Option<ModelHandle<T>> {
3600 cx.upgrade_model_handle(self)
3601 }
3602}
3603
3604impl<T> Hash for WeakModelHandle<T> {
3605 fn hash<H: Hasher>(&self, state: &mut H) {
3606 self.model_id.hash(state)
3607 }
3608}
3609
3610impl<T> PartialEq for WeakModelHandle<T> {
3611 fn eq(&self, other: &Self) -> bool {
3612 self.model_id == other.model_id
3613 }
3614}
3615
3616impl<T> Eq for WeakModelHandle<T> {}
3617
3618impl<T> Clone for WeakModelHandle<T> {
3619 fn clone(&self) -> Self {
3620 Self {
3621 model_id: self.model_id,
3622 model_type: PhantomData,
3623 }
3624 }
3625}
3626
3627impl<T> Copy for WeakModelHandle<T> {}
3628
3629pub struct ViewHandle<T> {
3630 window_id: usize,
3631 view_id: usize,
3632 view_type: PhantomData<T>,
3633 ref_counts: Arc<Mutex<RefCounts>>,
3634 #[cfg(any(test, feature = "test-support"))]
3635 handle_id: usize,
3636}
3637
3638impl<T: View> ViewHandle<T> {
3639 fn new(window_id: usize, view_id: usize, ref_counts: &Arc<Mutex<RefCounts>>) -> Self {
3640 ref_counts.lock().inc_view(window_id, view_id);
3641 #[cfg(any(test, feature = "test-support"))]
3642 let handle_id = ref_counts
3643 .lock()
3644 .leak_detector
3645 .lock()
3646 .handle_created(Some(type_name::<T>()), view_id);
3647
3648 Self {
3649 window_id,
3650 view_id,
3651 view_type: PhantomData,
3652 ref_counts: ref_counts.clone(),
3653
3654 #[cfg(any(test, feature = "test-support"))]
3655 handle_id,
3656 }
3657 }
3658
3659 pub fn downgrade(&self) -> WeakViewHandle<T> {
3660 WeakViewHandle::new(self.window_id, self.view_id)
3661 }
3662
3663 pub fn window_id(&self) -> usize {
3664 self.window_id
3665 }
3666
3667 pub fn id(&self) -> usize {
3668 self.view_id
3669 }
3670
3671 pub fn read<'a, C: ReadView>(&self, cx: &'a C) -> &'a T {
3672 cx.read_view(self)
3673 }
3674
3675 pub fn read_with<C, F, S>(&self, cx: &C, read: F) -> S
3676 where
3677 C: ReadViewWith,
3678 F: FnOnce(&T, &AppContext) -> S,
3679 {
3680 let mut read = Some(read);
3681 cx.read_view_with(self, &mut |view, cx| {
3682 let read = read.take().unwrap();
3683 read(view, cx)
3684 })
3685 }
3686
3687 pub fn update<C, F, S>(&self, cx: &mut C, update: F) -> S
3688 where
3689 C: UpdateView,
3690 F: FnOnce(&mut T, &mut ViewContext<T>) -> S,
3691 {
3692 let mut update = Some(update);
3693 cx.update_view(self, &mut |view, cx| {
3694 let update = update.take().unwrap();
3695 update(view, cx)
3696 })
3697 }
3698
3699 pub fn defer<C, F>(&self, cx: &mut C, update: F)
3700 where
3701 C: AsMut<MutableAppContext>,
3702 F: 'static + FnOnce(&mut T, &mut ViewContext<T>),
3703 {
3704 let this = self.clone();
3705 cx.as_mut().defer(move |cx| {
3706 this.update(cx, |view, cx| update(view, cx));
3707 });
3708 }
3709
3710 pub fn is_focused(&self, cx: &AppContext) -> bool {
3711 cx.focused_view_id(self.window_id)
3712 .map_or(false, |focused_id| focused_id == self.view_id)
3713 }
3714
3715 #[cfg(any(test, feature = "test-support"))]
3716 pub fn next_notification(&self, cx: &TestAppContext) -> impl Future<Output = ()> {
3717 use postage::prelude::{Sink as _, Stream as _};
3718
3719 let (mut tx, mut rx) = postage::mpsc::channel(1);
3720 let mut cx = cx.cx.borrow_mut();
3721 let subscription = cx.observe(self, move |_, _| {
3722 tx.try_send(()).ok();
3723 });
3724
3725 let duration = if std::env::var("CI").is_ok() {
3726 Duration::from_secs(5)
3727 } else {
3728 Duration::from_secs(1)
3729 };
3730
3731 async move {
3732 let notification = crate::util::timeout(duration, rx.recv())
3733 .await
3734 .expect("next notification timed out");
3735 drop(subscription);
3736 notification.expect("model dropped while test was waiting for its next notification")
3737 }
3738 }
3739
3740 #[cfg(any(test, feature = "test-support"))]
3741 pub fn condition(
3742 &self,
3743 cx: &TestAppContext,
3744 mut predicate: impl FnMut(&T, &AppContext) -> bool,
3745 ) -> impl Future<Output = ()> {
3746 use postage::prelude::{Sink as _, Stream as _};
3747
3748 let (tx, mut rx) = postage::mpsc::channel(1024);
3749
3750 let mut cx = cx.cx.borrow_mut();
3751 let subscriptions = self.update(&mut *cx, |_, cx| {
3752 (
3753 cx.observe(self, {
3754 let mut tx = tx.clone();
3755 move |_, _, _| {
3756 tx.blocking_send(()).ok();
3757 }
3758 }),
3759 cx.subscribe(self, {
3760 let mut tx = tx.clone();
3761 move |_, _, _, _| {
3762 tx.blocking_send(()).ok();
3763 }
3764 }),
3765 )
3766 });
3767
3768 let cx = cx.weak_self.as_ref().unwrap().upgrade().unwrap();
3769 let handle = self.downgrade();
3770 let duration = if std::env::var("CI").is_ok() {
3771 Duration::from_secs(2)
3772 } else {
3773 Duration::from_millis(500)
3774 };
3775
3776 async move {
3777 crate::util::timeout(duration, async move {
3778 loop {
3779 {
3780 let cx = cx.borrow();
3781 let cx = cx.as_ref();
3782 if predicate(
3783 handle
3784 .upgrade(cx)
3785 .expect("view dropped with pending condition")
3786 .read(cx),
3787 cx,
3788 ) {
3789 break;
3790 }
3791 }
3792
3793 cx.borrow().foreground().start_waiting();
3794 rx.recv()
3795 .await
3796 .expect("view dropped with pending condition");
3797 cx.borrow().foreground().finish_waiting();
3798 }
3799 })
3800 .await
3801 .expect("condition timed out");
3802 drop(subscriptions);
3803 }
3804 }
3805}
3806
3807impl<T: View> Clone for ViewHandle<T> {
3808 fn clone(&self) -> Self {
3809 ViewHandle::new(self.window_id, self.view_id, &self.ref_counts)
3810 }
3811}
3812
3813impl<T> PartialEq for ViewHandle<T> {
3814 fn eq(&self, other: &Self) -> bool {
3815 self.window_id == other.window_id && self.view_id == other.view_id
3816 }
3817}
3818
3819impl<T> PartialEq<WeakViewHandle<T>> for ViewHandle<T> {
3820 fn eq(&self, other: &WeakViewHandle<T>) -> bool {
3821 self.window_id == other.window_id && self.view_id == other.view_id
3822 }
3823}
3824
3825impl<T> PartialEq<ViewHandle<T>> for WeakViewHandle<T> {
3826 fn eq(&self, other: &ViewHandle<T>) -> bool {
3827 self.window_id == other.window_id && self.view_id == other.view_id
3828 }
3829}
3830
3831impl<T> Eq for ViewHandle<T> {}
3832
3833impl<T> Hash for ViewHandle<T> {
3834 fn hash<H: Hasher>(&self, state: &mut H) {
3835 self.window_id.hash(state);
3836 self.view_id.hash(state);
3837 }
3838}
3839
3840impl<T> Debug for ViewHandle<T> {
3841 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
3842 f.debug_struct(&format!("ViewHandle<{}>", type_name::<T>()))
3843 .field("window_id", &self.window_id)
3844 .field("view_id", &self.view_id)
3845 .finish()
3846 }
3847}
3848
3849impl<T> Drop for ViewHandle<T> {
3850 fn drop(&mut self) {
3851 self.ref_counts
3852 .lock()
3853 .dec_view(self.window_id, self.view_id);
3854 #[cfg(any(test, feature = "test-support"))]
3855 self.ref_counts
3856 .lock()
3857 .leak_detector
3858 .lock()
3859 .handle_dropped(self.view_id, self.handle_id);
3860 }
3861}
3862
3863impl<T: View> Handle<T> for ViewHandle<T> {
3864 type Weak = WeakViewHandle<T>;
3865
3866 fn id(&self) -> usize {
3867 self.view_id
3868 }
3869
3870 fn location(&self) -> EntityLocation {
3871 EntityLocation::View(self.window_id, self.view_id)
3872 }
3873
3874 fn downgrade(&self) -> Self::Weak {
3875 self.downgrade()
3876 }
3877
3878 fn upgrade_from(weak: &Self::Weak, cx: &AppContext) -> Option<Self>
3879 where
3880 Self: Sized,
3881 {
3882 weak.upgrade(cx)
3883 }
3884}
3885
3886pub struct AnyViewHandle {
3887 window_id: usize,
3888 view_id: usize,
3889 view_type: TypeId,
3890 ref_counts: Arc<Mutex<RefCounts>>,
3891
3892 #[cfg(any(test, feature = "test-support"))]
3893 handle_id: usize,
3894}
3895
3896impl AnyViewHandle {
3897 fn new(
3898 window_id: usize,
3899 view_id: usize,
3900 view_type: TypeId,
3901 ref_counts: Arc<Mutex<RefCounts>>,
3902 ) -> Self {
3903 ref_counts.lock().inc_view(window_id, view_id);
3904
3905 #[cfg(any(test, feature = "test-support"))]
3906 let handle_id = ref_counts
3907 .lock()
3908 .leak_detector
3909 .lock()
3910 .handle_created(None, view_id);
3911
3912 Self {
3913 window_id,
3914 view_id,
3915 view_type,
3916 ref_counts,
3917 #[cfg(any(test, feature = "test-support"))]
3918 handle_id,
3919 }
3920 }
3921
3922 pub fn id(&self) -> usize {
3923 self.view_id
3924 }
3925
3926 pub fn is<T: 'static>(&self) -> bool {
3927 TypeId::of::<T>() == self.view_type
3928 }
3929
3930 pub fn is_focused(&self, cx: &AppContext) -> bool {
3931 cx.focused_view_id(self.window_id)
3932 .map_or(false, |focused_id| focused_id == self.view_id)
3933 }
3934
3935 pub fn downcast<T: View>(self) -> Option<ViewHandle<T>> {
3936 if self.is::<T>() {
3937 let result = Some(ViewHandle {
3938 window_id: self.window_id,
3939 view_id: self.view_id,
3940 ref_counts: self.ref_counts.clone(),
3941 view_type: PhantomData,
3942 #[cfg(any(test, feature = "test-support"))]
3943 handle_id: self.handle_id,
3944 });
3945 unsafe {
3946 Arc::decrement_strong_count(&self.ref_counts);
3947 }
3948 std::mem::forget(self);
3949 result
3950 } else {
3951 None
3952 }
3953 }
3954
3955 pub fn downgrade(&self) -> AnyWeakViewHandle {
3956 AnyWeakViewHandle {
3957 window_id: self.window_id,
3958 view_id: self.view_id,
3959 view_type: self.view_type,
3960 }
3961 }
3962
3963 pub fn view_type(&self) -> TypeId {
3964 self.view_type
3965 }
3966}
3967
3968impl Clone for AnyViewHandle {
3969 fn clone(&self) -> Self {
3970 Self::new(
3971 self.window_id,
3972 self.view_id,
3973 self.view_type,
3974 self.ref_counts.clone(),
3975 )
3976 }
3977}
3978
3979impl From<&AnyViewHandle> for AnyViewHandle {
3980 fn from(handle: &AnyViewHandle) -> Self {
3981 handle.clone()
3982 }
3983}
3984
3985impl<T: View> From<&ViewHandle<T>> for AnyViewHandle {
3986 fn from(handle: &ViewHandle<T>) -> Self {
3987 Self::new(
3988 handle.window_id,
3989 handle.view_id,
3990 TypeId::of::<T>(),
3991 handle.ref_counts.clone(),
3992 )
3993 }
3994}
3995
3996impl<T: View> From<ViewHandle<T>> for AnyViewHandle {
3997 fn from(handle: ViewHandle<T>) -> Self {
3998 let any_handle = AnyViewHandle {
3999 window_id: handle.window_id,
4000 view_id: handle.view_id,
4001 view_type: TypeId::of::<T>(),
4002 ref_counts: handle.ref_counts.clone(),
4003 #[cfg(any(test, feature = "test-support"))]
4004 handle_id: handle.handle_id,
4005 };
4006 unsafe {
4007 Arc::decrement_strong_count(&handle.ref_counts);
4008 }
4009 std::mem::forget(handle);
4010 any_handle
4011 }
4012}
4013
4014impl Drop for AnyViewHandle {
4015 fn drop(&mut self) {
4016 self.ref_counts
4017 .lock()
4018 .dec_view(self.window_id, self.view_id);
4019 #[cfg(any(test, feature = "test-support"))]
4020 self.ref_counts
4021 .lock()
4022 .leak_detector
4023 .lock()
4024 .handle_dropped(self.view_id, self.handle_id);
4025 }
4026}
4027
4028pub struct AnyModelHandle {
4029 model_id: usize,
4030 model_type: TypeId,
4031 ref_counts: Arc<Mutex<RefCounts>>,
4032
4033 #[cfg(any(test, feature = "test-support"))]
4034 handle_id: usize,
4035}
4036
4037impl AnyModelHandle {
4038 fn new(model_id: usize, model_type: TypeId, ref_counts: Arc<Mutex<RefCounts>>) -> Self {
4039 ref_counts.lock().inc_model(model_id);
4040
4041 #[cfg(any(test, feature = "test-support"))]
4042 let handle_id = ref_counts
4043 .lock()
4044 .leak_detector
4045 .lock()
4046 .handle_created(None, model_id);
4047
4048 Self {
4049 model_id,
4050 model_type,
4051 ref_counts,
4052
4053 #[cfg(any(test, feature = "test-support"))]
4054 handle_id,
4055 }
4056 }
4057
4058 pub fn downcast<T: Entity>(self) -> Option<ModelHandle<T>> {
4059 if self.is::<T>() {
4060 let result = Some(ModelHandle {
4061 model_id: self.model_id,
4062 model_type: PhantomData,
4063 ref_counts: self.ref_counts.clone(),
4064
4065 #[cfg(any(test, feature = "test-support"))]
4066 handle_id: self.handle_id,
4067 });
4068 unsafe {
4069 Arc::decrement_strong_count(&self.ref_counts);
4070 }
4071 std::mem::forget(self);
4072 result
4073 } else {
4074 None
4075 }
4076 }
4077
4078 pub fn downgrade(&self) -> AnyWeakModelHandle {
4079 AnyWeakModelHandle {
4080 model_id: self.model_id,
4081 model_type: self.model_type,
4082 }
4083 }
4084
4085 pub fn is<T: Entity>(&self) -> bool {
4086 self.model_type == TypeId::of::<T>()
4087 }
4088
4089 pub fn model_type(&self) -> TypeId {
4090 self.model_type
4091 }
4092}
4093
4094impl<T: Entity> From<ModelHandle<T>> for AnyModelHandle {
4095 fn from(handle: ModelHandle<T>) -> Self {
4096 Self::new(
4097 handle.model_id,
4098 TypeId::of::<T>(),
4099 handle.ref_counts.clone(),
4100 )
4101 }
4102}
4103
4104impl Clone for AnyModelHandle {
4105 fn clone(&self) -> Self {
4106 Self::new(self.model_id, self.model_type, self.ref_counts.clone())
4107 }
4108}
4109
4110impl Drop for AnyModelHandle {
4111 fn drop(&mut self) {
4112 let mut ref_counts = self.ref_counts.lock();
4113 ref_counts.dec_model(self.model_id);
4114
4115 #[cfg(any(test, feature = "test-support"))]
4116 ref_counts
4117 .leak_detector
4118 .lock()
4119 .handle_dropped(self.model_id, self.handle_id);
4120 }
4121}
4122
4123pub struct AnyWeakModelHandle {
4124 model_id: usize,
4125 model_type: TypeId,
4126}
4127
4128impl AnyWeakModelHandle {
4129 pub fn upgrade(&self, cx: &impl UpgradeModelHandle) -> Option<AnyModelHandle> {
4130 cx.upgrade_any_model_handle(self)
4131 }
4132}
4133
4134impl<T: Entity> From<WeakModelHandle<T>> for AnyWeakModelHandle {
4135 fn from(handle: WeakModelHandle<T>) -> Self {
4136 AnyWeakModelHandle {
4137 model_id: handle.model_id,
4138 model_type: TypeId::of::<T>(),
4139 }
4140 }
4141}
4142
4143pub struct WeakViewHandle<T> {
4144 window_id: usize,
4145 view_id: usize,
4146 view_type: PhantomData<T>,
4147}
4148
4149impl<T: View> WeakViewHandle<T> {
4150 fn new(window_id: usize, view_id: usize) -> Self {
4151 Self {
4152 window_id,
4153 view_id,
4154 view_type: PhantomData,
4155 }
4156 }
4157
4158 pub fn id(&self) -> usize {
4159 self.view_id
4160 }
4161
4162 pub fn upgrade(&self, cx: &impl UpgradeViewHandle) -> Option<ViewHandle<T>> {
4163 cx.upgrade_view_handle(self)
4164 }
4165}
4166
4167impl<T> Clone for WeakViewHandle<T> {
4168 fn clone(&self) -> Self {
4169 Self {
4170 window_id: self.window_id,
4171 view_id: self.view_id,
4172 view_type: PhantomData,
4173 }
4174 }
4175}
4176
4177impl<T> PartialEq for WeakViewHandle<T> {
4178 fn eq(&self, other: &Self) -> bool {
4179 self.window_id == other.window_id && self.view_id == other.view_id
4180 }
4181}
4182
4183impl<T> Eq for WeakViewHandle<T> {}
4184
4185impl<T> Hash for WeakViewHandle<T> {
4186 fn hash<H: Hasher>(&self, state: &mut H) {
4187 self.window_id.hash(state);
4188 self.view_id.hash(state);
4189 }
4190}
4191
4192pub struct AnyWeakViewHandle {
4193 window_id: usize,
4194 view_id: usize,
4195 view_type: TypeId,
4196}
4197
4198impl AnyWeakViewHandle {
4199 pub fn upgrade(&self, cx: &impl UpgradeViewHandle) -> Option<AnyViewHandle> {
4200 cx.upgrade_any_view_handle(self)
4201 }
4202}
4203
4204impl<T: View> From<WeakViewHandle<T>> for AnyWeakViewHandle {
4205 fn from(handle: WeakViewHandle<T>) -> Self {
4206 AnyWeakViewHandle {
4207 window_id: handle.window_id,
4208 view_id: handle.view_id,
4209 view_type: TypeId::of::<T>(),
4210 }
4211 }
4212}
4213
4214#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
4215pub struct ElementStateId {
4216 view_id: usize,
4217 element_id: usize,
4218 tag: TypeId,
4219}
4220
4221pub struct ElementStateHandle<T> {
4222 value_type: PhantomData<T>,
4223 id: ElementStateId,
4224 ref_counts: Weak<Mutex<RefCounts>>,
4225}
4226
4227impl<T: 'static> ElementStateHandle<T> {
4228 fn new(id: ElementStateId, frame_id: usize, ref_counts: &Arc<Mutex<RefCounts>>) -> Self {
4229 ref_counts.lock().inc_element_state(id, frame_id);
4230 Self {
4231 value_type: PhantomData,
4232 id,
4233 ref_counts: Arc::downgrade(ref_counts),
4234 }
4235 }
4236
4237 pub fn read<'a>(&self, cx: &'a AppContext) -> &'a T {
4238 cx.element_states
4239 .get(&self.id)
4240 .unwrap()
4241 .downcast_ref()
4242 .unwrap()
4243 }
4244
4245 pub fn update<C, R>(&self, cx: &mut C, f: impl FnOnce(&mut T, &mut C) -> R) -> R
4246 where
4247 C: DerefMut<Target = MutableAppContext>,
4248 {
4249 let mut element_state = cx.deref_mut().cx.element_states.remove(&self.id).unwrap();
4250 let result = f(element_state.downcast_mut().unwrap(), cx);
4251 cx.deref_mut()
4252 .cx
4253 .element_states
4254 .insert(self.id, element_state);
4255 result
4256 }
4257}
4258
4259impl<T> Drop for ElementStateHandle<T> {
4260 fn drop(&mut self) {
4261 if let Some(ref_counts) = self.ref_counts.upgrade() {
4262 ref_counts.lock().dec_element_state(self.id);
4263 }
4264 }
4265}
4266
4267pub struct CursorStyleHandle {
4268 id: usize,
4269 next_cursor_style_handle_id: Arc<AtomicUsize>,
4270 platform: Arc<dyn Platform>,
4271}
4272
4273impl Drop for CursorStyleHandle {
4274 fn drop(&mut self) {
4275 if self.id + 1 == self.next_cursor_style_handle_id.load(SeqCst) {
4276 self.platform.set_cursor_style(CursorStyle::Arrow);
4277 }
4278 }
4279}
4280
4281#[must_use]
4282pub enum Subscription {
4283 Subscription {
4284 id: usize,
4285 entity_id: usize,
4286 subscriptions:
4287 Option<Weak<Mutex<HashMap<usize, BTreeMap<usize, Option<SubscriptionCallback>>>>>>,
4288 },
4289 GlobalSubscription {
4290 id: usize,
4291 type_id: TypeId,
4292 subscriptions: Option<
4293 Weak<Mutex<HashMap<TypeId, BTreeMap<usize, Option<GlobalSubscriptionCallback>>>>>,
4294 >,
4295 },
4296 Observation {
4297 id: usize,
4298 entity_id: usize,
4299 observations:
4300 Option<Weak<Mutex<HashMap<usize, BTreeMap<usize, Option<ObservationCallback>>>>>>,
4301 },
4302 GlobalObservation {
4303 id: usize,
4304 type_id: TypeId,
4305 observations: Option<
4306 Weak<Mutex<HashMap<TypeId, BTreeMap<usize, Option<GlobalObservationCallback>>>>>,
4307 >,
4308 },
4309 ReleaseObservation {
4310 id: usize,
4311 entity_id: usize,
4312 observations:
4313 Option<Weak<Mutex<HashMap<usize, BTreeMap<usize, ReleaseObservationCallback>>>>>,
4314 },
4315}
4316
4317impl Subscription {
4318 pub fn detach(&mut self) {
4319 match self {
4320 Subscription::Subscription { subscriptions, .. } => {
4321 subscriptions.take();
4322 }
4323 Subscription::GlobalSubscription { subscriptions, .. } => {
4324 subscriptions.take();
4325 }
4326 Subscription::Observation { observations, .. } => {
4327 observations.take();
4328 }
4329 Subscription::GlobalObservation { observations, .. } => {
4330 observations.take();
4331 }
4332 Subscription::ReleaseObservation { observations, .. } => {
4333 observations.take();
4334 }
4335 }
4336 }
4337}
4338
4339impl Drop for Subscription {
4340 fn drop(&mut self) {
4341 match self {
4342 Subscription::Subscription {
4343 id,
4344 entity_id,
4345 subscriptions,
4346 } => {
4347 if let Some(subscriptions) = subscriptions.as_ref().and_then(Weak::upgrade) {
4348 match subscriptions
4349 .lock()
4350 .entry(*entity_id)
4351 .or_default()
4352 .entry(*id)
4353 {
4354 btree_map::Entry::Vacant(entry) => {
4355 entry.insert(None);
4356 }
4357 btree_map::Entry::Occupied(entry) => {
4358 entry.remove();
4359 }
4360 }
4361 }
4362 }
4363 Subscription::GlobalSubscription {
4364 id,
4365 type_id,
4366 subscriptions,
4367 } => {
4368 if let Some(subscriptions) = subscriptions.as_ref().and_then(Weak::upgrade) {
4369 match subscriptions.lock().entry(*type_id).or_default().entry(*id) {
4370 btree_map::Entry::Vacant(entry) => {
4371 entry.insert(None);
4372 }
4373 btree_map::Entry::Occupied(entry) => {
4374 entry.remove();
4375 }
4376 }
4377 }
4378 }
4379 Subscription::Observation {
4380 id,
4381 entity_id,
4382 observations,
4383 } => {
4384 if let Some(observations) = observations.as_ref().and_then(Weak::upgrade) {
4385 match observations
4386 .lock()
4387 .entry(*entity_id)
4388 .or_default()
4389 .entry(*id)
4390 {
4391 btree_map::Entry::Vacant(entry) => {
4392 entry.insert(None);
4393 }
4394 btree_map::Entry::Occupied(entry) => {
4395 entry.remove();
4396 }
4397 }
4398 }
4399 }
4400 Subscription::GlobalObservation {
4401 id,
4402 type_id,
4403 observations,
4404 } => {
4405 if let Some(observations) = observations.as_ref().and_then(Weak::upgrade) {
4406 match observations.lock().entry(*type_id).or_default().entry(*id) {
4407 collections::btree_map::Entry::Vacant(entry) => {
4408 entry.insert(None);
4409 }
4410 collections::btree_map::Entry::Occupied(entry) => {
4411 entry.remove();
4412 }
4413 }
4414 }
4415 }
4416 Subscription::ReleaseObservation {
4417 id,
4418 entity_id,
4419 observations,
4420 } => {
4421 if let Some(observations) = observations.as_ref().and_then(Weak::upgrade) {
4422 if let Some(observations) = observations.lock().get_mut(entity_id) {
4423 observations.remove(id);
4424 }
4425 }
4426 }
4427 }
4428 }
4429}
4430
4431lazy_static! {
4432 static ref LEAK_BACKTRACE: bool =
4433 std::env::var("LEAK_BACKTRACE").map_or(false, |b| !b.is_empty());
4434}
4435
4436#[cfg(any(test, feature = "test-support"))]
4437#[derive(Default)]
4438pub struct LeakDetector {
4439 next_handle_id: usize,
4440 handle_backtraces: HashMap<
4441 usize,
4442 (
4443 Option<&'static str>,
4444 HashMap<usize, Option<backtrace::Backtrace>>,
4445 ),
4446 >,
4447}
4448
4449#[cfg(any(test, feature = "test-support"))]
4450impl LeakDetector {
4451 fn handle_created(&mut self, type_name: Option<&'static str>, entity_id: usize) -> usize {
4452 let handle_id = post_inc(&mut self.next_handle_id);
4453 let entry = self.handle_backtraces.entry(entity_id).or_default();
4454 let backtrace = if *LEAK_BACKTRACE {
4455 Some(backtrace::Backtrace::new_unresolved())
4456 } else {
4457 None
4458 };
4459 if let Some(type_name) = type_name {
4460 entry.0.get_or_insert(type_name);
4461 }
4462 entry.1.insert(handle_id, backtrace);
4463 handle_id
4464 }
4465
4466 fn handle_dropped(&mut self, entity_id: usize, handle_id: usize) {
4467 if let Some((_, backtraces)) = self.handle_backtraces.get_mut(&entity_id) {
4468 assert!(backtraces.remove(&handle_id).is_some());
4469 if backtraces.is_empty() {
4470 self.handle_backtraces.remove(&entity_id);
4471 }
4472 }
4473 }
4474
4475 pub fn detect(&mut self) {
4476 let mut found_leaks = false;
4477 for (id, (type_name, backtraces)) in self.handle_backtraces.iter_mut() {
4478 eprintln!(
4479 "leaked {} handles to {:?} {}",
4480 backtraces.len(),
4481 type_name.unwrap_or("entity"),
4482 id
4483 );
4484 for trace in backtraces.values_mut() {
4485 if let Some(trace) = trace {
4486 trace.resolve();
4487 eprintln!("{:?}", crate::util::CwdBacktrace(trace));
4488 }
4489 }
4490 found_leaks = true;
4491 }
4492
4493 let hint = if *LEAK_BACKTRACE {
4494 ""
4495 } else {
4496 " – set LEAK_BACKTRACE=1 for more information"
4497 };
4498 assert!(!found_leaks, "detected leaked handles{}", hint);
4499 }
4500}
4501
4502#[derive(Default)]
4503struct RefCounts {
4504 entity_counts: HashMap<usize, usize>,
4505 element_state_counts: HashMap<ElementStateId, ElementStateRefCount>,
4506 dropped_models: HashSet<usize>,
4507 dropped_views: HashSet<(usize, usize)>,
4508 dropped_element_states: HashSet<ElementStateId>,
4509
4510 #[cfg(any(test, feature = "test-support"))]
4511 leak_detector: Arc<Mutex<LeakDetector>>,
4512}
4513
4514struct ElementStateRefCount {
4515 ref_count: usize,
4516 frame_id: usize,
4517}
4518
4519impl RefCounts {
4520 fn inc_model(&mut self, model_id: usize) {
4521 match self.entity_counts.entry(model_id) {
4522 Entry::Occupied(mut entry) => {
4523 *entry.get_mut() += 1;
4524 }
4525 Entry::Vacant(entry) => {
4526 entry.insert(1);
4527 self.dropped_models.remove(&model_id);
4528 }
4529 }
4530 }
4531
4532 fn inc_view(&mut self, window_id: usize, view_id: usize) {
4533 match self.entity_counts.entry(view_id) {
4534 Entry::Occupied(mut entry) => *entry.get_mut() += 1,
4535 Entry::Vacant(entry) => {
4536 entry.insert(1);
4537 self.dropped_views.remove(&(window_id, view_id));
4538 }
4539 }
4540 }
4541
4542 fn inc_element_state(&mut self, id: ElementStateId, frame_id: usize) {
4543 match self.element_state_counts.entry(id) {
4544 Entry::Occupied(mut entry) => {
4545 let entry = entry.get_mut();
4546 if entry.frame_id == frame_id || entry.ref_count >= 2 {
4547 panic!("used the same element state more than once in the same frame");
4548 }
4549 entry.ref_count += 1;
4550 entry.frame_id = frame_id;
4551 }
4552 Entry::Vacant(entry) => {
4553 entry.insert(ElementStateRefCount {
4554 ref_count: 1,
4555 frame_id,
4556 });
4557 self.dropped_element_states.remove(&id);
4558 }
4559 }
4560 }
4561
4562 fn dec_model(&mut self, model_id: usize) {
4563 let count = self.entity_counts.get_mut(&model_id).unwrap();
4564 *count -= 1;
4565 if *count == 0 {
4566 self.entity_counts.remove(&model_id);
4567 self.dropped_models.insert(model_id);
4568 }
4569 }
4570
4571 fn dec_view(&mut self, window_id: usize, view_id: usize) {
4572 let count = self.entity_counts.get_mut(&view_id).unwrap();
4573 *count -= 1;
4574 if *count == 0 {
4575 self.entity_counts.remove(&view_id);
4576 self.dropped_views.insert((window_id, view_id));
4577 }
4578 }
4579
4580 fn dec_element_state(&mut self, id: ElementStateId) {
4581 let entry = self.element_state_counts.get_mut(&id).unwrap();
4582 entry.ref_count -= 1;
4583 if entry.ref_count == 0 {
4584 self.element_state_counts.remove(&id);
4585 self.dropped_element_states.insert(id);
4586 }
4587 }
4588
4589 fn is_entity_alive(&self, entity_id: usize) -> bool {
4590 self.entity_counts.contains_key(&entity_id)
4591 }
4592
4593 fn take_dropped(
4594 &mut self,
4595 ) -> (
4596 HashSet<usize>,
4597 HashSet<(usize, usize)>,
4598 HashSet<ElementStateId>,
4599 ) {
4600 (
4601 std::mem::take(&mut self.dropped_models),
4602 std::mem::take(&mut self.dropped_views),
4603 std::mem::take(&mut self.dropped_element_states),
4604 )
4605 }
4606}
4607
4608#[cfg(test)]
4609mod tests {
4610 use super::*;
4611 use crate::elements::*;
4612 use smol::future::poll_once;
4613 use std::{
4614 cell::Cell,
4615 sync::atomic::{AtomicBool, AtomicUsize, Ordering::SeqCst},
4616 };
4617
4618 #[crate::test(self)]
4619 fn test_model_handles(cx: &mut MutableAppContext) {
4620 struct Model {
4621 other: Option<ModelHandle<Model>>,
4622 events: Vec<String>,
4623 }
4624
4625 impl Entity for Model {
4626 type Event = usize;
4627 }
4628
4629 impl Model {
4630 fn new(other: Option<ModelHandle<Self>>, cx: &mut ModelContext<Self>) -> Self {
4631 if let Some(other) = other.as_ref() {
4632 cx.observe(other, |me, _, _| {
4633 me.events.push("notified".into());
4634 })
4635 .detach();
4636 cx.subscribe(other, |me, _, event, _| {
4637 me.events.push(format!("observed event {}", event));
4638 })
4639 .detach();
4640 }
4641
4642 Self {
4643 other,
4644 events: Vec::new(),
4645 }
4646 }
4647 }
4648
4649 let handle_1 = cx.add_model(|cx| Model::new(None, cx));
4650 let handle_2 = cx.add_model(|cx| Model::new(Some(handle_1.clone()), cx));
4651 assert_eq!(cx.cx.models.len(), 2);
4652
4653 handle_1.update(cx, |model, cx| {
4654 model.events.push("updated".into());
4655 cx.emit(1);
4656 cx.notify();
4657 cx.emit(2);
4658 });
4659 assert_eq!(handle_1.read(cx).events, vec!["updated".to_string()]);
4660 assert_eq!(
4661 handle_2.read(cx).events,
4662 vec![
4663 "observed event 1".to_string(),
4664 "notified".to_string(),
4665 "observed event 2".to_string(),
4666 ]
4667 );
4668
4669 handle_2.update(cx, |model, _| {
4670 drop(handle_1);
4671 model.other.take();
4672 });
4673
4674 assert_eq!(cx.cx.models.len(), 1);
4675 assert!(cx.subscriptions.lock().is_empty());
4676 assert!(cx.observations.lock().is_empty());
4677 }
4678
4679 #[crate::test(self)]
4680 fn test_model_events(cx: &mut MutableAppContext) {
4681 #[derive(Default)]
4682 struct Model {
4683 events: Vec<usize>,
4684 }
4685
4686 impl Entity for Model {
4687 type Event = usize;
4688 }
4689
4690 let handle_1 = cx.add_model(|_| Model::default());
4691 let handle_2 = cx.add_model(|_| Model::default());
4692
4693 handle_1.update(cx, |_, cx| {
4694 cx.subscribe(&handle_2, move |model: &mut Model, emitter, event, cx| {
4695 model.events.push(*event);
4696
4697 cx.subscribe(&emitter, |model, _, event, _| {
4698 model.events.push(*event * 2);
4699 })
4700 .detach();
4701 })
4702 .detach();
4703 });
4704
4705 handle_2.update(cx, |_, c| c.emit(7));
4706 assert_eq!(handle_1.read(cx).events, vec![7]);
4707
4708 handle_2.update(cx, |_, c| c.emit(5));
4709 assert_eq!(handle_1.read(cx).events, vec![7, 5, 10]);
4710 }
4711
4712 #[crate::test(self)]
4713 fn test_model_emit_before_subscribe_in_same_update_cycle(cx: &mut MutableAppContext) {
4714 #[derive(Default)]
4715 struct Model;
4716
4717 impl Entity for Model {
4718 type Event = ();
4719 }
4720
4721 let events = Rc::new(RefCell::new(Vec::new()));
4722 cx.add_model(|cx| {
4723 drop(cx.subscribe(&cx.handle(), {
4724 let events = events.clone();
4725 move |_, _, _, _| events.borrow_mut().push("dropped before flush")
4726 }));
4727 cx.subscribe(&cx.handle(), {
4728 let events = events.clone();
4729 move |_, _, _, _| events.borrow_mut().push("before emit")
4730 })
4731 .detach();
4732 cx.emit(());
4733 cx.subscribe(&cx.handle(), {
4734 let events = events.clone();
4735 move |_, _, _, _| events.borrow_mut().push("after emit")
4736 })
4737 .detach();
4738 Model
4739 });
4740 assert_eq!(*events.borrow(), ["before emit"]);
4741 }
4742
4743 #[crate::test(self)]
4744 fn test_observe_and_notify_from_model(cx: &mut MutableAppContext) {
4745 #[derive(Default)]
4746 struct Model {
4747 count: usize,
4748 events: Vec<usize>,
4749 }
4750
4751 impl Entity for Model {
4752 type Event = ();
4753 }
4754
4755 let handle_1 = cx.add_model(|_| Model::default());
4756 let handle_2 = cx.add_model(|_| Model::default());
4757
4758 handle_1.update(cx, |_, c| {
4759 c.observe(&handle_2, move |model, observed, c| {
4760 model.events.push(observed.read(c).count);
4761 c.observe(&observed, |model, observed, c| {
4762 model.events.push(observed.read(c).count * 2);
4763 })
4764 .detach();
4765 })
4766 .detach();
4767 });
4768
4769 handle_2.update(cx, |model, c| {
4770 model.count = 7;
4771 c.notify()
4772 });
4773 assert_eq!(handle_1.read(cx).events, vec![7]);
4774
4775 handle_2.update(cx, |model, c| {
4776 model.count = 5;
4777 c.notify()
4778 });
4779 assert_eq!(handle_1.read(cx).events, vec![7, 5, 10])
4780 }
4781
4782 #[crate::test(self)]
4783 fn test_model_notify_before_observe_in_same_update_cycle(cx: &mut MutableAppContext) {
4784 #[derive(Default)]
4785 struct Model;
4786
4787 impl Entity for Model {
4788 type Event = ();
4789 }
4790
4791 let events = Rc::new(RefCell::new(Vec::new()));
4792 cx.add_model(|cx| {
4793 drop(cx.observe(&cx.handle(), {
4794 let events = events.clone();
4795 move |_, _, _| events.borrow_mut().push("dropped before flush")
4796 }));
4797 cx.observe(&cx.handle(), {
4798 let events = events.clone();
4799 move |_, _, _| events.borrow_mut().push("before notify")
4800 })
4801 .detach();
4802 cx.notify();
4803 cx.observe(&cx.handle(), {
4804 let events = events.clone();
4805 move |_, _, _| events.borrow_mut().push("after notify")
4806 })
4807 .detach();
4808 Model
4809 });
4810 assert_eq!(*events.borrow(), ["before notify"]);
4811 }
4812
4813 #[crate::test(self)]
4814 fn test_defer_and_after_window_update(cx: &mut MutableAppContext) {
4815 struct View {
4816 render_count: usize,
4817 }
4818
4819 impl Entity for View {
4820 type Event = usize;
4821 }
4822
4823 impl super::View for View {
4824 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
4825 post_inc(&mut self.render_count);
4826 Empty::new().boxed()
4827 }
4828
4829 fn ui_name() -> &'static str {
4830 "View"
4831 }
4832 }
4833
4834 let (_, view) = cx.add_window(Default::default(), |_| View { render_count: 0 });
4835 let called_defer = Rc::new(AtomicBool::new(false));
4836 let called_after_window_update = Rc::new(AtomicBool::new(false));
4837
4838 view.update(cx, |this, cx| {
4839 assert_eq!(this.render_count, 1);
4840 cx.defer({
4841 let called_defer = called_defer.clone();
4842 move |this, _| {
4843 assert_eq!(this.render_count, 1);
4844 called_defer.store(true, SeqCst);
4845 }
4846 });
4847 cx.after_window_update({
4848 let called_after_window_update = called_after_window_update.clone();
4849 move |this, cx| {
4850 assert_eq!(this.render_count, 2);
4851 called_after_window_update.store(true, SeqCst);
4852 cx.notify();
4853 }
4854 });
4855 assert!(!called_defer.load(SeqCst));
4856 assert!(!called_after_window_update.load(SeqCst));
4857 cx.notify();
4858 });
4859
4860 assert!(called_defer.load(SeqCst));
4861 assert!(called_after_window_update.load(SeqCst));
4862 assert_eq!(view.read(cx).render_count, 3);
4863 }
4864
4865 #[crate::test(self)]
4866 fn test_view_handles(cx: &mut MutableAppContext) {
4867 struct View {
4868 other: Option<ViewHandle<View>>,
4869 events: Vec<String>,
4870 }
4871
4872 impl Entity for View {
4873 type Event = usize;
4874 }
4875
4876 impl super::View for View {
4877 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
4878 Empty::new().boxed()
4879 }
4880
4881 fn ui_name() -> &'static str {
4882 "View"
4883 }
4884 }
4885
4886 impl View {
4887 fn new(other: Option<ViewHandle<View>>, cx: &mut ViewContext<Self>) -> Self {
4888 if let Some(other) = other.as_ref() {
4889 cx.subscribe(other, |me, _, event, _| {
4890 me.events.push(format!("observed event {}", event));
4891 })
4892 .detach();
4893 }
4894 Self {
4895 other,
4896 events: Vec::new(),
4897 }
4898 }
4899 }
4900
4901 let (window_id, _) = cx.add_window(Default::default(), |cx| View::new(None, cx));
4902 let handle_1 = cx.add_view(window_id, |cx| View::new(None, cx));
4903 let handle_2 = cx.add_view(window_id, |cx| View::new(Some(handle_1.clone()), cx));
4904 assert_eq!(cx.cx.views.len(), 3);
4905
4906 handle_1.update(cx, |view, cx| {
4907 view.events.push("updated".into());
4908 cx.emit(1);
4909 cx.emit(2);
4910 });
4911 assert_eq!(handle_1.read(cx).events, vec!["updated".to_string()]);
4912 assert_eq!(
4913 handle_2.read(cx).events,
4914 vec![
4915 "observed event 1".to_string(),
4916 "observed event 2".to_string(),
4917 ]
4918 );
4919
4920 handle_2.update(cx, |view, _| {
4921 drop(handle_1);
4922 view.other.take();
4923 });
4924
4925 assert_eq!(cx.cx.views.len(), 2);
4926 assert!(cx.subscriptions.lock().is_empty());
4927 assert!(cx.observations.lock().is_empty());
4928 }
4929
4930 #[crate::test(self)]
4931 fn test_add_window(cx: &mut MutableAppContext) {
4932 struct View {
4933 mouse_down_count: Arc<AtomicUsize>,
4934 }
4935
4936 impl Entity for View {
4937 type Event = ();
4938 }
4939
4940 impl super::View for View {
4941 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
4942 let mouse_down_count = self.mouse_down_count.clone();
4943 EventHandler::new(Empty::new().boxed())
4944 .on_mouse_down(move |_| {
4945 mouse_down_count.fetch_add(1, SeqCst);
4946 true
4947 })
4948 .boxed()
4949 }
4950
4951 fn ui_name() -> &'static str {
4952 "View"
4953 }
4954 }
4955
4956 let mouse_down_count = Arc::new(AtomicUsize::new(0));
4957 let (window_id, _) = cx.add_window(Default::default(), |_| View {
4958 mouse_down_count: mouse_down_count.clone(),
4959 });
4960 let presenter = cx.presenters_and_platform_windows[&window_id].0.clone();
4961 // Ensure window's root element is in a valid lifecycle state.
4962 presenter.borrow_mut().dispatch_event(
4963 Event::LeftMouseDown {
4964 position: Default::default(),
4965 ctrl: false,
4966 alt: false,
4967 shift: false,
4968 cmd: false,
4969 click_count: 1,
4970 },
4971 cx,
4972 );
4973 assert_eq!(mouse_down_count.load(SeqCst), 1);
4974 }
4975
4976 #[crate::test(self)]
4977 fn test_entity_release_hooks(cx: &mut MutableAppContext) {
4978 struct Model {
4979 released: Rc<Cell<bool>>,
4980 }
4981
4982 struct View {
4983 released: Rc<Cell<bool>>,
4984 }
4985
4986 impl Entity for Model {
4987 type Event = ();
4988
4989 fn release(&mut self, _: &mut MutableAppContext) {
4990 self.released.set(true);
4991 }
4992 }
4993
4994 impl Entity for View {
4995 type Event = ();
4996
4997 fn release(&mut self, _: &mut MutableAppContext) {
4998 self.released.set(true);
4999 }
5000 }
5001
5002 impl super::View for View {
5003 fn ui_name() -> &'static str {
5004 "View"
5005 }
5006
5007 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
5008 Empty::new().boxed()
5009 }
5010 }
5011
5012 let model_released = Rc::new(Cell::new(false));
5013 let model_release_observed = Rc::new(Cell::new(false));
5014 let view_released = Rc::new(Cell::new(false));
5015 let view_release_observed = Rc::new(Cell::new(false));
5016
5017 let model = cx.add_model(|_| Model {
5018 released: model_released.clone(),
5019 });
5020 let (window_id, view) = cx.add_window(Default::default(), |_| View {
5021 released: view_released.clone(),
5022 });
5023 assert!(!model_released.get());
5024 assert!(!view_released.get());
5025
5026 cx.observe_release(&model, {
5027 let model_release_observed = model_release_observed.clone();
5028 move |_, _| model_release_observed.set(true)
5029 })
5030 .detach();
5031 cx.observe_release(&view, {
5032 let view_release_observed = view_release_observed.clone();
5033 move |_, _| view_release_observed.set(true)
5034 })
5035 .detach();
5036
5037 cx.update(move |_| {
5038 drop(model);
5039 });
5040 assert!(model_released.get());
5041 assert!(model_release_observed.get());
5042
5043 drop(view);
5044 cx.remove_window(window_id);
5045 assert!(view_released.get());
5046 assert!(view_release_observed.get());
5047 }
5048
5049 #[crate::test(self)]
5050 fn test_view_events(cx: &mut MutableAppContext) {
5051 #[derive(Default)]
5052 struct View {
5053 events: Vec<usize>,
5054 }
5055
5056 impl Entity for View {
5057 type Event = usize;
5058 }
5059
5060 impl super::View for View {
5061 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
5062 Empty::new().boxed()
5063 }
5064
5065 fn ui_name() -> &'static str {
5066 "View"
5067 }
5068 }
5069
5070 struct Model;
5071
5072 impl Entity for Model {
5073 type Event = usize;
5074 }
5075
5076 let (window_id, handle_1) = cx.add_window(Default::default(), |_| View::default());
5077 let handle_2 = cx.add_view(window_id, |_| View::default());
5078 let handle_3 = cx.add_model(|_| Model);
5079
5080 handle_1.update(cx, |_, cx| {
5081 cx.subscribe(&handle_2, move |me, emitter, event, cx| {
5082 me.events.push(*event);
5083
5084 cx.subscribe(&emitter, |me, _, event, _| {
5085 me.events.push(*event * 2);
5086 })
5087 .detach();
5088 })
5089 .detach();
5090
5091 cx.subscribe(&handle_3, |me, _, event, _| {
5092 me.events.push(*event);
5093 })
5094 .detach();
5095 });
5096
5097 handle_2.update(cx, |_, c| c.emit(7));
5098 assert_eq!(handle_1.read(cx).events, vec![7]);
5099
5100 handle_2.update(cx, |_, c| c.emit(5));
5101 assert_eq!(handle_1.read(cx).events, vec![7, 5, 10]);
5102
5103 handle_3.update(cx, |_, c| c.emit(9));
5104 assert_eq!(handle_1.read(cx).events, vec![7, 5, 10, 9]);
5105 }
5106
5107 #[crate::test(self)]
5108 fn test_global_events(cx: &mut MutableAppContext) {
5109 #[derive(Clone, Debug, Eq, PartialEq)]
5110 struct GlobalEvent(u64);
5111
5112 let events = Rc::new(RefCell::new(Vec::new()));
5113 let first_subscription;
5114 let second_subscription;
5115
5116 {
5117 let events = events.clone();
5118 first_subscription = cx.subscribe_global(move |e: &GlobalEvent, _| {
5119 events.borrow_mut().push(("First", e.clone()));
5120 });
5121 }
5122
5123 {
5124 let events = events.clone();
5125 second_subscription = cx.subscribe_global(move |e: &GlobalEvent, _| {
5126 events.borrow_mut().push(("Second", e.clone()));
5127 });
5128 }
5129
5130 cx.update(|cx| {
5131 cx.emit_global(GlobalEvent(1));
5132 cx.emit_global(GlobalEvent(2));
5133 });
5134
5135 drop(first_subscription);
5136
5137 cx.update(|cx| {
5138 cx.emit_global(GlobalEvent(3));
5139 });
5140
5141 drop(second_subscription);
5142
5143 cx.update(|cx| {
5144 cx.emit_global(GlobalEvent(4));
5145 });
5146
5147 assert_eq!(
5148 &*events.borrow(),
5149 &[
5150 ("First", GlobalEvent(1)),
5151 ("Second", GlobalEvent(1)),
5152 ("First", GlobalEvent(2)),
5153 ("Second", GlobalEvent(2)),
5154 ("Second", GlobalEvent(3)),
5155 ]
5156 );
5157 }
5158
5159 #[crate::test(self)]
5160 fn test_global_events_emitted_before_subscription_in_same_update_cycle(
5161 cx: &mut MutableAppContext,
5162 ) {
5163 let events = Rc::new(RefCell::new(Vec::new()));
5164 cx.update(|cx| {
5165 {
5166 let events = events.clone();
5167 drop(cx.subscribe_global(move |_: &(), _| {
5168 events.borrow_mut().push("dropped before emit");
5169 }));
5170 }
5171
5172 {
5173 let events = events.clone();
5174 cx.subscribe_global(move |_: &(), _| {
5175 events.borrow_mut().push("before emit");
5176 })
5177 .detach();
5178 }
5179
5180 cx.emit_global(());
5181
5182 {
5183 let events = events.clone();
5184 cx.subscribe_global(move |_: &(), _| {
5185 events.borrow_mut().push("after emit");
5186 })
5187 .detach();
5188 }
5189 });
5190
5191 assert_eq!(*events.borrow(), ["before emit"]);
5192 }
5193
5194 #[crate::test(self)]
5195 fn test_global_nested_events(cx: &mut MutableAppContext) {
5196 #[derive(Clone, Debug, Eq, PartialEq)]
5197 struct GlobalEvent(u64);
5198
5199 let events = Rc::new(RefCell::new(Vec::new()));
5200
5201 {
5202 let events = events.clone();
5203 cx.subscribe_global(move |e: &GlobalEvent, cx| {
5204 events.borrow_mut().push(("Outer", e.clone()));
5205
5206 if e.0 == 1 {
5207 let events = events.clone();
5208 cx.subscribe_global(move |e: &GlobalEvent, _| {
5209 events.borrow_mut().push(("Inner", e.clone()));
5210 })
5211 .detach();
5212 }
5213 })
5214 .detach();
5215 }
5216
5217 cx.update(|cx| {
5218 cx.emit_global(GlobalEvent(1));
5219 cx.emit_global(GlobalEvent(2));
5220 cx.emit_global(GlobalEvent(3));
5221 });
5222 cx.update(|cx| {
5223 cx.emit_global(GlobalEvent(4));
5224 });
5225
5226 assert_eq!(
5227 &*events.borrow(),
5228 &[
5229 ("Outer", GlobalEvent(1)),
5230 ("Outer", GlobalEvent(2)),
5231 ("Outer", GlobalEvent(3)),
5232 ("Outer", GlobalEvent(4)),
5233 ("Inner", GlobalEvent(4)),
5234 ]
5235 );
5236 }
5237
5238 #[crate::test(self)]
5239 fn test_global(cx: &mut MutableAppContext) {
5240 type Global = usize;
5241
5242 let observation_count = Rc::new(RefCell::new(0));
5243 let subscription = cx.observe_global::<Global, _>({
5244 let observation_count = observation_count.clone();
5245 move |_, _| {
5246 *observation_count.borrow_mut() += 1;
5247 }
5248 });
5249
5250 assert!(!cx.has_global::<Global>());
5251 assert_eq!(cx.default_global::<Global>(), &0);
5252 assert_eq!(*observation_count.borrow(), 1);
5253 assert!(cx.has_global::<Global>());
5254 assert_eq!(
5255 cx.update_global::<Global, _, _>(|global, _| {
5256 *global = 1;
5257 "Update Result"
5258 }),
5259 "Update Result"
5260 );
5261 assert_eq!(*observation_count.borrow(), 2);
5262 assert_eq!(cx.global::<Global>(), &1);
5263
5264 drop(subscription);
5265 cx.update_global::<Global, _, _>(|global, _| {
5266 *global = 2;
5267 });
5268 assert_eq!(*observation_count.borrow(), 2);
5269
5270 type OtherGlobal = f32;
5271
5272 let observation_count = Rc::new(RefCell::new(0));
5273 cx.observe_global::<OtherGlobal, _>({
5274 let observation_count = observation_count.clone();
5275 move |_, _| {
5276 *observation_count.borrow_mut() += 1;
5277 }
5278 })
5279 .detach();
5280
5281 assert_eq!(
5282 cx.update_default_global::<OtherGlobal, _, _>(|global, _| {
5283 assert_eq!(global, &0.0);
5284 *global = 2.0;
5285 "Default update result"
5286 }),
5287 "Default update result"
5288 );
5289 assert_eq!(cx.global::<OtherGlobal>(), &2.0);
5290 assert_eq!(*observation_count.borrow(), 1);
5291 }
5292
5293 #[crate::test(self)]
5294 fn test_dropping_subscribers(cx: &mut MutableAppContext) {
5295 struct View;
5296
5297 impl Entity for View {
5298 type Event = ();
5299 }
5300
5301 impl super::View for View {
5302 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
5303 Empty::new().boxed()
5304 }
5305
5306 fn ui_name() -> &'static str {
5307 "View"
5308 }
5309 }
5310
5311 struct Model;
5312
5313 impl Entity for Model {
5314 type Event = ();
5315 }
5316
5317 let (window_id, _) = cx.add_window(Default::default(), |_| View);
5318 let observing_view = cx.add_view(window_id, |_| View);
5319 let emitting_view = cx.add_view(window_id, |_| View);
5320 let observing_model = cx.add_model(|_| Model);
5321 let observed_model = cx.add_model(|_| Model);
5322
5323 observing_view.update(cx, |_, cx| {
5324 cx.subscribe(&emitting_view, |_, _, _, _| {}).detach();
5325 cx.subscribe(&observed_model, |_, _, _, _| {}).detach();
5326 });
5327 observing_model.update(cx, |_, cx| {
5328 cx.subscribe(&observed_model, |_, _, _, _| {}).detach();
5329 });
5330
5331 cx.update(|_| {
5332 drop(observing_view);
5333 drop(observing_model);
5334 });
5335
5336 emitting_view.update(cx, |_, cx| cx.emit(()));
5337 observed_model.update(cx, |_, cx| cx.emit(()));
5338 }
5339
5340 #[crate::test(self)]
5341 fn test_view_emit_before_subscribe_in_same_update_cycle(cx: &mut MutableAppContext) {
5342 #[derive(Default)]
5343 struct TestView;
5344
5345 impl Entity for TestView {
5346 type Event = ();
5347 }
5348
5349 impl View for TestView {
5350 fn ui_name() -> &'static str {
5351 "TestView"
5352 }
5353
5354 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
5355 Empty::new().boxed()
5356 }
5357 }
5358
5359 let events = Rc::new(RefCell::new(Vec::new()));
5360 cx.add_window(Default::default(), |cx| {
5361 drop(cx.subscribe(&cx.handle(), {
5362 let events = events.clone();
5363 move |_, _, _, _| events.borrow_mut().push("dropped before flush")
5364 }));
5365 cx.subscribe(&cx.handle(), {
5366 let events = events.clone();
5367 move |_, _, _, _| events.borrow_mut().push("before emit")
5368 })
5369 .detach();
5370 cx.emit(());
5371 cx.subscribe(&cx.handle(), {
5372 let events = events.clone();
5373 move |_, _, _, _| events.borrow_mut().push("after emit")
5374 })
5375 .detach();
5376 TestView
5377 });
5378 assert_eq!(*events.borrow(), ["before emit"]);
5379 }
5380
5381 #[crate::test(self)]
5382 fn test_observe_and_notify_from_view(cx: &mut MutableAppContext) {
5383 #[derive(Default)]
5384 struct View {
5385 events: Vec<usize>,
5386 }
5387
5388 impl Entity for View {
5389 type Event = usize;
5390 }
5391
5392 impl super::View for View {
5393 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
5394 Empty::new().boxed()
5395 }
5396
5397 fn ui_name() -> &'static str {
5398 "View"
5399 }
5400 }
5401
5402 #[derive(Default)]
5403 struct Model {
5404 count: usize,
5405 }
5406
5407 impl Entity for Model {
5408 type Event = ();
5409 }
5410
5411 let (_, view) = cx.add_window(Default::default(), |_| View::default());
5412 let model = cx.add_model(|_| Model::default());
5413
5414 view.update(cx, |_, c| {
5415 c.observe(&model, |me, observed, c| {
5416 me.events.push(observed.read(c).count)
5417 })
5418 .detach();
5419 });
5420
5421 model.update(cx, |model, c| {
5422 model.count = 11;
5423 c.notify();
5424 });
5425 assert_eq!(view.read(cx).events, vec![11]);
5426 }
5427
5428 #[crate::test(self)]
5429 fn test_view_notify_before_observe_in_same_update_cycle(cx: &mut MutableAppContext) {
5430 #[derive(Default)]
5431 struct TestView;
5432
5433 impl Entity for TestView {
5434 type Event = ();
5435 }
5436
5437 impl View for TestView {
5438 fn ui_name() -> &'static str {
5439 "TestView"
5440 }
5441
5442 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
5443 Empty::new().boxed()
5444 }
5445 }
5446
5447 let events = Rc::new(RefCell::new(Vec::new()));
5448 cx.add_window(Default::default(), |cx| {
5449 drop(cx.observe(&cx.handle(), {
5450 let events = events.clone();
5451 move |_, _, _| events.borrow_mut().push("dropped before flush")
5452 }));
5453 cx.observe(&cx.handle(), {
5454 let events = events.clone();
5455 move |_, _, _| events.borrow_mut().push("before notify")
5456 })
5457 .detach();
5458 cx.notify();
5459 cx.observe(&cx.handle(), {
5460 let events = events.clone();
5461 move |_, _, _| events.borrow_mut().push("after notify")
5462 })
5463 .detach();
5464 TestView
5465 });
5466 assert_eq!(*events.borrow(), ["before notify"]);
5467 }
5468
5469 #[crate::test(self)]
5470 fn test_dropping_observers(cx: &mut MutableAppContext) {
5471 struct View;
5472
5473 impl Entity for View {
5474 type Event = ();
5475 }
5476
5477 impl super::View for View {
5478 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
5479 Empty::new().boxed()
5480 }
5481
5482 fn ui_name() -> &'static str {
5483 "View"
5484 }
5485 }
5486
5487 struct Model;
5488
5489 impl Entity for Model {
5490 type Event = ();
5491 }
5492
5493 let (window_id, _) = cx.add_window(Default::default(), |_| View);
5494 let observing_view = cx.add_view(window_id, |_| View);
5495 let observing_model = cx.add_model(|_| Model);
5496 let observed_model = cx.add_model(|_| Model);
5497
5498 observing_view.update(cx, |_, cx| {
5499 cx.observe(&observed_model, |_, _, _| {}).detach();
5500 });
5501 observing_model.update(cx, |_, cx| {
5502 cx.observe(&observed_model, |_, _, _| {}).detach();
5503 });
5504
5505 cx.update(|_| {
5506 drop(observing_view);
5507 drop(observing_model);
5508 });
5509
5510 observed_model.update(cx, |_, cx| cx.notify());
5511 }
5512
5513 #[crate::test(self)]
5514 fn test_dropping_subscriptions_during_callback(cx: &mut MutableAppContext) {
5515 struct Model;
5516
5517 impl Entity for Model {
5518 type Event = u64;
5519 }
5520
5521 // Events
5522 let observing_model = cx.add_model(|_| Model);
5523 let observed_model = cx.add_model(|_| Model);
5524
5525 let events = Rc::new(RefCell::new(Vec::new()));
5526
5527 observing_model.update(cx, |_, cx| {
5528 let events = events.clone();
5529 let subscription = Rc::new(RefCell::new(None));
5530 *subscription.borrow_mut() = Some(cx.subscribe(&observed_model, {
5531 let subscription = subscription.clone();
5532 move |_, _, e, _| {
5533 subscription.borrow_mut().take();
5534 events.borrow_mut().push(e.clone());
5535 }
5536 }));
5537 });
5538
5539 observed_model.update(cx, |_, cx| {
5540 cx.emit(1);
5541 cx.emit(2);
5542 });
5543
5544 assert_eq!(*events.borrow(), [1]);
5545
5546 // Global Events
5547 #[derive(Clone, Debug, Eq, PartialEq)]
5548 struct GlobalEvent(u64);
5549
5550 let events = Rc::new(RefCell::new(Vec::new()));
5551
5552 {
5553 let events = events.clone();
5554 let subscription = Rc::new(RefCell::new(None));
5555 *subscription.borrow_mut() = Some(cx.subscribe_global({
5556 let subscription = subscription.clone();
5557 move |e: &GlobalEvent, _| {
5558 subscription.borrow_mut().take();
5559 events.borrow_mut().push(e.clone());
5560 }
5561 }));
5562 }
5563
5564 cx.update(|cx| {
5565 cx.emit_global(GlobalEvent(1));
5566 cx.emit_global(GlobalEvent(2));
5567 });
5568
5569 assert_eq!(*events.borrow(), [GlobalEvent(1)]);
5570
5571 // Model Observation
5572 let observing_model = cx.add_model(|_| Model);
5573 let observed_model = cx.add_model(|_| Model);
5574
5575 let observation_count = Rc::new(RefCell::new(0));
5576
5577 observing_model.update(cx, |_, cx| {
5578 let observation_count = observation_count.clone();
5579 let subscription = Rc::new(RefCell::new(None));
5580 *subscription.borrow_mut() = Some(cx.observe(&observed_model, {
5581 let subscription = subscription.clone();
5582 move |_, _, _| {
5583 subscription.borrow_mut().take();
5584 *observation_count.borrow_mut() += 1;
5585 }
5586 }));
5587 });
5588
5589 observed_model.update(cx, |_, cx| {
5590 cx.notify();
5591 });
5592
5593 observed_model.update(cx, |_, cx| {
5594 cx.notify();
5595 });
5596
5597 assert_eq!(*observation_count.borrow(), 1);
5598
5599 // View Observation
5600 struct View;
5601
5602 impl Entity for View {
5603 type Event = ();
5604 }
5605
5606 impl super::View for View {
5607 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
5608 Empty::new().boxed()
5609 }
5610
5611 fn ui_name() -> &'static str {
5612 "View"
5613 }
5614 }
5615
5616 let (window_id, _) = cx.add_window(Default::default(), |_| View);
5617 let observing_view = cx.add_view(window_id, |_| View);
5618 let observed_view = cx.add_view(window_id, |_| View);
5619
5620 let observation_count = Rc::new(RefCell::new(0));
5621 observing_view.update(cx, |_, cx| {
5622 let observation_count = observation_count.clone();
5623 let subscription = Rc::new(RefCell::new(None));
5624 *subscription.borrow_mut() = Some(cx.observe(&observed_view, {
5625 let subscription = subscription.clone();
5626 move |_, _, _| {
5627 subscription.borrow_mut().take();
5628 *observation_count.borrow_mut() += 1;
5629 }
5630 }));
5631 });
5632
5633 observed_view.update(cx, |_, cx| {
5634 cx.notify();
5635 });
5636
5637 observed_view.update(cx, |_, cx| {
5638 cx.notify();
5639 });
5640
5641 assert_eq!(*observation_count.borrow(), 1);
5642
5643 // Global Observation
5644 let observation_count = Rc::new(RefCell::new(0));
5645 let subscription = Rc::new(RefCell::new(None));
5646 *subscription.borrow_mut() = Some(cx.observe_global::<(), _>({
5647 let observation_count = observation_count.clone();
5648 let subscription = subscription.clone();
5649 move |_, _| {
5650 subscription.borrow_mut().take();
5651 *observation_count.borrow_mut() += 1;
5652 }
5653 }));
5654
5655 cx.default_global::<()>();
5656 cx.set_global(());
5657 assert_eq!(*observation_count.borrow(), 1);
5658 }
5659
5660 #[crate::test(self)]
5661 fn test_focus(cx: &mut MutableAppContext) {
5662 struct View {
5663 name: String,
5664 events: Arc<Mutex<Vec<String>>>,
5665 }
5666
5667 impl Entity for View {
5668 type Event = ();
5669 }
5670
5671 impl super::View for View {
5672 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
5673 Empty::new().boxed()
5674 }
5675
5676 fn ui_name() -> &'static str {
5677 "View"
5678 }
5679
5680 fn on_focus(&mut self, _: &mut ViewContext<Self>) {
5681 self.events.lock().push(format!("{} focused", &self.name));
5682 }
5683
5684 fn on_blur(&mut self, _: &mut ViewContext<Self>) {
5685 self.events.lock().push(format!("{} blurred", &self.name));
5686 }
5687 }
5688
5689 let events: Arc<Mutex<Vec<String>>> = Default::default();
5690 let (window_id, view_1) = cx.add_window(Default::default(), |_| View {
5691 events: events.clone(),
5692 name: "view 1".to_string(),
5693 });
5694 let view_2 = cx.add_view(window_id, |_| View {
5695 events: events.clone(),
5696 name: "view 2".to_string(),
5697 });
5698
5699 view_1.update(cx, |_, cx| cx.focus(&view_2));
5700 view_1.update(cx, |_, cx| cx.focus(&view_1));
5701 view_1.update(cx, |_, cx| cx.focus(&view_2));
5702 view_1.update(cx, |_, _| drop(view_2));
5703
5704 assert_eq!(
5705 *events.lock(),
5706 [
5707 "view 1 focused".to_string(),
5708 "view 1 blurred".to_string(),
5709 "view 2 focused".to_string(),
5710 "view 2 blurred".to_string(),
5711 "view 1 focused".to_string(),
5712 "view 1 blurred".to_string(),
5713 "view 2 focused".to_string(),
5714 "view 1 focused".to_string(),
5715 ],
5716 );
5717 }
5718
5719 #[crate::test(self)]
5720 fn test_dispatch_action(cx: &mut MutableAppContext) {
5721 struct ViewA {
5722 id: usize,
5723 }
5724
5725 impl Entity for ViewA {
5726 type Event = ();
5727 }
5728
5729 impl View for ViewA {
5730 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
5731 Empty::new().boxed()
5732 }
5733
5734 fn ui_name() -> &'static str {
5735 "View"
5736 }
5737 }
5738
5739 struct ViewB {
5740 id: usize,
5741 }
5742
5743 impl Entity for ViewB {
5744 type Event = ();
5745 }
5746
5747 impl View for ViewB {
5748 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
5749 Empty::new().boxed()
5750 }
5751
5752 fn ui_name() -> &'static str {
5753 "View"
5754 }
5755 }
5756
5757 action!(Action, &'static str);
5758
5759 let actions = Rc::new(RefCell::new(Vec::new()));
5760
5761 {
5762 let actions = actions.clone();
5763 cx.add_global_action(move |_: &Action, _: &mut MutableAppContext| {
5764 actions.borrow_mut().push("global".to_string());
5765 });
5766 }
5767
5768 {
5769 let actions = actions.clone();
5770 cx.add_action(move |view: &mut ViewA, action: &Action, cx| {
5771 assert_eq!(action.0, "bar");
5772 cx.propagate_action();
5773 actions.borrow_mut().push(format!("{} a", view.id));
5774 });
5775 }
5776
5777 {
5778 let actions = actions.clone();
5779 cx.add_action(move |view: &mut ViewA, _: &Action, cx| {
5780 if view.id != 1 {
5781 cx.add_view(|cx| {
5782 cx.propagate_action(); // Still works on a nested ViewContext
5783 ViewB { id: 5 }
5784 });
5785 }
5786 actions.borrow_mut().push(format!("{} b", view.id));
5787 });
5788 }
5789
5790 {
5791 let actions = actions.clone();
5792 cx.add_action(move |view: &mut ViewB, _: &Action, cx| {
5793 cx.propagate_action();
5794 actions.borrow_mut().push(format!("{} c", view.id));
5795 });
5796 }
5797
5798 {
5799 let actions = actions.clone();
5800 cx.add_action(move |view: &mut ViewB, _: &Action, cx| {
5801 cx.propagate_action();
5802 actions.borrow_mut().push(format!("{} d", view.id));
5803 });
5804 }
5805
5806 {
5807 let actions = actions.clone();
5808 cx.capture_action(move |view: &mut ViewA, _: &Action, cx| {
5809 cx.propagate_action();
5810 actions.borrow_mut().push(format!("{} capture", view.id));
5811 });
5812 }
5813
5814 let (window_id, view_1) = cx.add_window(Default::default(), |_| ViewA { id: 1 });
5815 let view_2 = cx.add_view(window_id, |_| ViewB { id: 2 });
5816 let view_3 = cx.add_view(window_id, |_| ViewA { id: 3 });
5817 let view_4 = cx.add_view(window_id, |_| ViewB { id: 4 });
5818
5819 cx.dispatch_action(
5820 window_id,
5821 vec![view_1.id(), view_2.id(), view_3.id(), view_4.id()],
5822 &Action("bar"),
5823 );
5824
5825 assert_eq!(
5826 *actions.borrow(),
5827 vec![
5828 "1 capture",
5829 "3 capture",
5830 "4 d",
5831 "4 c",
5832 "3 b",
5833 "3 a",
5834 "2 d",
5835 "2 c",
5836 "1 b"
5837 ]
5838 );
5839
5840 // Remove view_1, which doesn't propagate the action
5841 actions.borrow_mut().clear();
5842 cx.dispatch_action(
5843 window_id,
5844 vec![view_2.id(), view_3.id(), view_4.id()],
5845 &Action("bar"),
5846 );
5847
5848 assert_eq!(
5849 *actions.borrow(),
5850 vec![
5851 "3 capture",
5852 "4 d",
5853 "4 c",
5854 "3 b",
5855 "3 a",
5856 "2 d",
5857 "2 c",
5858 "global"
5859 ]
5860 );
5861 }
5862
5863 #[crate::test(self)]
5864 fn test_dispatch_keystroke(cx: &mut MutableAppContext) {
5865 action!(Action, &'static str);
5866
5867 struct View {
5868 id: usize,
5869 keymap_context: keymap::Context,
5870 }
5871
5872 impl Entity for View {
5873 type Event = ();
5874 }
5875
5876 impl super::View for View {
5877 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
5878 Empty::new().boxed()
5879 }
5880
5881 fn ui_name() -> &'static str {
5882 "View"
5883 }
5884
5885 fn keymap_context(&self, _: &AppContext) -> keymap::Context {
5886 self.keymap_context.clone()
5887 }
5888 }
5889
5890 impl View {
5891 fn new(id: usize) -> Self {
5892 View {
5893 id,
5894 keymap_context: keymap::Context::default(),
5895 }
5896 }
5897 }
5898
5899 let mut view_1 = View::new(1);
5900 let mut view_2 = View::new(2);
5901 let mut view_3 = View::new(3);
5902 view_1.keymap_context.set.insert("a".into());
5903 view_2.keymap_context.set.insert("a".into());
5904 view_2.keymap_context.set.insert("b".into());
5905 view_3.keymap_context.set.insert("a".into());
5906 view_3.keymap_context.set.insert("b".into());
5907 view_3.keymap_context.set.insert("c".into());
5908
5909 let (window_id, view_1) = cx.add_window(Default::default(), |_| view_1);
5910 let view_2 = cx.add_view(window_id, |_| view_2);
5911 let view_3 = cx.add_view(window_id, |_| view_3);
5912
5913 // This keymap's only binding dispatches an action on view 2 because that view will have
5914 // "a" and "b" in its context, but not "c".
5915 cx.add_bindings(vec![keymap::Binding::new(
5916 "a",
5917 Action("a"),
5918 Some("a && b && !c"),
5919 )]);
5920
5921 cx.add_bindings(vec![keymap::Binding::new("b", Action("b"), None)]);
5922
5923 let actions = Rc::new(RefCell::new(Vec::new()));
5924 {
5925 let actions = actions.clone();
5926 cx.add_action(move |view: &mut View, action: &Action, cx| {
5927 if action.0 == "a" {
5928 actions.borrow_mut().push(format!("{} a", view.id));
5929 } else {
5930 actions
5931 .borrow_mut()
5932 .push(format!("{} {}", view.id, action.0));
5933 cx.propagate_action();
5934 }
5935 });
5936 }
5937 {
5938 let actions = actions.clone();
5939 cx.add_global_action(move |action: &Action, _| {
5940 actions.borrow_mut().push(format!("global {}", action.0));
5941 });
5942 }
5943
5944 cx.dispatch_keystroke(
5945 window_id,
5946 vec![view_1.id(), view_2.id(), view_3.id()],
5947 &Keystroke::parse("a").unwrap(),
5948 );
5949
5950 assert_eq!(&*actions.borrow(), &["2 a"]);
5951
5952 actions.borrow_mut().clear();
5953 cx.dispatch_keystroke(
5954 window_id,
5955 vec![view_1.id(), view_2.id(), view_3.id()],
5956 &Keystroke::parse("b").unwrap(),
5957 );
5958
5959 assert_eq!(&*actions.borrow(), &["3 b", "2 b", "1 b", "global b"]);
5960 }
5961
5962 #[crate::test(self)]
5963 async fn test_model_condition(cx: &mut TestAppContext) {
5964 struct Counter(usize);
5965
5966 impl super::Entity for Counter {
5967 type Event = ();
5968 }
5969
5970 impl Counter {
5971 fn inc(&mut self, cx: &mut ModelContext<Self>) {
5972 self.0 += 1;
5973 cx.notify();
5974 }
5975 }
5976
5977 let model = cx.add_model(|_| Counter(0));
5978
5979 let condition1 = model.condition(&cx, |model, _| model.0 == 2);
5980 let condition2 = model.condition(&cx, |model, _| model.0 == 3);
5981 smol::pin!(condition1, condition2);
5982
5983 model.update(cx, |model, cx| model.inc(cx));
5984 assert_eq!(poll_once(&mut condition1).await, None);
5985 assert_eq!(poll_once(&mut condition2).await, None);
5986
5987 model.update(cx, |model, cx| model.inc(cx));
5988 assert_eq!(poll_once(&mut condition1).await, Some(()));
5989 assert_eq!(poll_once(&mut condition2).await, None);
5990
5991 model.update(cx, |model, cx| model.inc(cx));
5992 assert_eq!(poll_once(&mut condition2).await, Some(()));
5993
5994 model.update(cx, |_, cx| cx.notify());
5995 }
5996
5997 #[crate::test(self)]
5998 #[should_panic]
5999 async fn test_model_condition_timeout(cx: &mut TestAppContext) {
6000 struct Model;
6001
6002 impl super::Entity for Model {
6003 type Event = ();
6004 }
6005
6006 let model = cx.add_model(|_| Model);
6007 model.condition(&cx, |_, _| false).await;
6008 }
6009
6010 #[crate::test(self)]
6011 #[should_panic(expected = "model dropped with pending condition")]
6012 async fn test_model_condition_panic_on_drop(cx: &mut TestAppContext) {
6013 struct Model;
6014
6015 impl super::Entity for Model {
6016 type Event = ();
6017 }
6018
6019 let model = cx.add_model(|_| Model);
6020 let condition = model.condition(&cx, |_, _| false);
6021 cx.update(|_| drop(model));
6022 condition.await;
6023 }
6024
6025 #[crate::test(self)]
6026 async fn test_view_condition(cx: &mut TestAppContext) {
6027 struct Counter(usize);
6028
6029 impl super::Entity for Counter {
6030 type Event = ();
6031 }
6032
6033 impl super::View for Counter {
6034 fn ui_name() -> &'static str {
6035 "test view"
6036 }
6037
6038 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
6039 Empty::new().boxed()
6040 }
6041 }
6042
6043 impl Counter {
6044 fn inc(&mut self, cx: &mut ViewContext<Self>) {
6045 self.0 += 1;
6046 cx.notify();
6047 }
6048 }
6049
6050 let (_, view) = cx.add_window(|_| Counter(0));
6051
6052 let condition1 = view.condition(&cx, |view, _| view.0 == 2);
6053 let condition2 = view.condition(&cx, |view, _| view.0 == 3);
6054 smol::pin!(condition1, condition2);
6055
6056 view.update(cx, |view, cx| view.inc(cx));
6057 assert_eq!(poll_once(&mut condition1).await, None);
6058 assert_eq!(poll_once(&mut condition2).await, None);
6059
6060 view.update(cx, |view, cx| view.inc(cx));
6061 assert_eq!(poll_once(&mut condition1).await, Some(()));
6062 assert_eq!(poll_once(&mut condition2).await, None);
6063
6064 view.update(cx, |view, cx| view.inc(cx));
6065 assert_eq!(poll_once(&mut condition2).await, Some(()));
6066 view.update(cx, |_, cx| cx.notify());
6067 }
6068
6069 #[crate::test(self)]
6070 #[should_panic]
6071 async fn test_view_condition_timeout(cx: &mut TestAppContext) {
6072 struct View;
6073
6074 impl super::Entity for View {
6075 type Event = ();
6076 }
6077
6078 impl super::View for View {
6079 fn ui_name() -> &'static str {
6080 "test view"
6081 }
6082
6083 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
6084 Empty::new().boxed()
6085 }
6086 }
6087
6088 let (_, view) = cx.add_window(|_| View);
6089 view.condition(&cx, |_, _| false).await;
6090 }
6091
6092 #[crate::test(self)]
6093 #[should_panic(expected = "view dropped with pending condition")]
6094 async fn test_view_condition_panic_on_drop(cx: &mut TestAppContext) {
6095 struct View;
6096
6097 impl super::Entity for View {
6098 type Event = ();
6099 }
6100
6101 impl super::View for View {
6102 fn ui_name() -> &'static str {
6103 "test view"
6104 }
6105
6106 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
6107 Empty::new().boxed()
6108 }
6109 }
6110
6111 let window_id = cx.add_window(|_| View).0;
6112 let view = cx.add_view(window_id, |_| View);
6113
6114 let condition = view.condition(&cx, |_, _| false);
6115 cx.update(|_| drop(view));
6116 condition.await;
6117 }
6118
6119 #[crate::test(self)]
6120 fn test_refresh_windows(cx: &mut MutableAppContext) {
6121 struct View(usize);
6122
6123 impl super::Entity for View {
6124 type Event = ();
6125 }
6126
6127 impl super::View for View {
6128 fn ui_name() -> &'static str {
6129 "test view"
6130 }
6131
6132 fn render(&mut self, _: &mut RenderContext<Self>) -> ElementBox {
6133 Empty::new().named(format!("render count: {}", post_inc(&mut self.0)))
6134 }
6135 }
6136
6137 let (window_id, root_view) = cx.add_window(Default::default(), |_| View(0));
6138 let presenter = cx.presenters_and_platform_windows[&window_id].0.clone();
6139
6140 assert_eq!(
6141 presenter.borrow().rendered_views[&root_view.id()].name(),
6142 Some("render count: 0")
6143 );
6144
6145 let view = cx.add_view(window_id, |cx| {
6146 cx.refresh_windows();
6147 View(0)
6148 });
6149
6150 assert_eq!(
6151 presenter.borrow().rendered_views[&root_view.id()].name(),
6152 Some("render count: 1")
6153 );
6154 assert_eq!(
6155 presenter.borrow().rendered_views[&view.id()].name(),
6156 Some("render count: 0")
6157 );
6158
6159 cx.update(|cx| cx.refresh_windows());
6160 assert_eq!(
6161 presenter.borrow().rendered_views[&root_view.id()].name(),
6162 Some("render count: 2")
6163 );
6164 assert_eq!(
6165 presenter.borrow().rendered_views[&view.id()].name(),
6166 Some("render count: 1")
6167 );
6168
6169 cx.update(|cx| {
6170 cx.refresh_windows();
6171 drop(view);
6172 });
6173 assert_eq!(
6174 presenter.borrow().rendered_views[&root_view.id()].name(),
6175 Some("render count: 3")
6176 );
6177 assert_eq!(presenter.borrow().rendered_views.len(), 1);
6178 }
6179}