1use crate::{
2 elements::ElementBox,
3 executor,
4 keymap::{self, Keystroke},
5 platform::{self, Platform, PromptLevel, WindowOptions},
6 presenter::Presenter,
7 util::{post_inc, timeout},
8 AssetCache, AssetSource, ClipboardItem, EventContext, FontCache, PathPromptOptions,
9 TextLayoutCache,
10};
11use anyhow::{anyhow, Result};
12use async_task::Task;
13use keymap::MatchResult;
14use parking_lot::{Mutex, RwLock};
15use platform::Event;
16use postage::{mpsc, sink::Sink as _, stream::Stream as _};
17use smol::prelude::*;
18use std::{
19 any::{type_name, Any, TypeId},
20 cell::RefCell,
21 collections::{hash_map::Entry, HashMap, HashSet, VecDeque},
22 fmt::{self, Debug},
23 hash::{Hash, Hasher},
24 marker::PhantomData,
25 ops::{Deref, DerefMut},
26 path::{Path, PathBuf},
27 rc::{self, Rc},
28 sync::{Arc, Weak},
29 time::Duration,
30};
31
32pub trait Entity: 'static {
33 type Event;
34
35 fn release(&mut self, _: &mut MutableAppContext) {}
36}
37
38pub trait View: Entity + Sized {
39 fn ui_name() -> &'static str;
40 fn render(&self, cx: &RenderContext<'_, Self>) -> ElementBox;
41 fn on_focus(&mut self, _: &mut ViewContext<Self>) {}
42 fn on_blur(&mut self, _: &mut ViewContext<Self>) {}
43 fn keymap_context(&self, _: &AppContext) -> keymap::Context {
44 Self::default_keymap_context()
45 }
46 fn default_keymap_context() -> keymap::Context {
47 let mut cx = keymap::Context::default();
48 cx.set.insert(Self::ui_name().into());
49 cx
50 }
51}
52
53pub trait ReadModel {
54 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T;
55}
56
57pub trait ReadModelWith {
58 fn read_model_with<E: Entity, F: FnOnce(&E, &AppContext) -> T, T>(
59 &self,
60 handle: &ModelHandle<E>,
61 read: F,
62 ) -> T;
63}
64
65pub trait UpdateModel {
66 fn update_model<T, F, S>(&mut self, handle: &ModelHandle<T>, update: F) -> S
67 where
68 T: Entity,
69 F: FnOnce(&mut T, &mut ModelContext<T>) -> S;
70}
71
72pub trait UpgradeModelHandle {
73 fn upgrade_model_handle<T: Entity>(&self, handle: WeakModelHandle<T>)
74 -> Option<ModelHandle<T>>;
75}
76
77pub trait ReadView {
78 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T;
79}
80
81pub trait ReadViewWith {
82 fn read_view_with<V, F, T>(&self, handle: &ViewHandle<V>, read: F) -> T
83 where
84 V: View,
85 F: FnOnce(&V, &AppContext) -> T;
86}
87
88pub trait UpdateView {
89 fn update_view<T, F, S>(&mut self, handle: &ViewHandle<T>, update: F) -> S
90 where
91 T: View,
92 F: FnOnce(&mut T, &mut ViewContext<T>) -> S;
93}
94
95pub trait Action: 'static + AnyAction {
96 type Argument: 'static + Clone;
97}
98
99pub trait AnyAction {
100 fn id(&self) -> TypeId;
101 fn name(&self) -> &'static str;
102 fn as_any(&self) -> &dyn Any;
103 fn boxed_clone(&self) -> Box<dyn AnyAction>;
104 fn boxed_clone_as_any(&self) -> Box<dyn Any>;
105}
106
107#[macro_export]
108macro_rules! action {
109 ($name:ident, $arg:ty) => {
110 #[derive(Clone)]
111 pub struct $name(pub $arg);
112
113 impl $crate::Action for $name {
114 type Argument = $arg;
115 }
116
117 impl $crate::AnyAction for $name {
118 fn id(&self) -> std::any::TypeId {
119 std::any::TypeId::of::<$name>()
120 }
121
122 fn name(&self) -> &'static str {
123 stringify!($name)
124 }
125
126 fn as_any(&self) -> &dyn std::any::Any {
127 self
128 }
129
130 fn boxed_clone(&self) -> Box<dyn $crate::AnyAction> {
131 Box::new(self.clone())
132 }
133
134 fn boxed_clone_as_any(&self) -> Box<dyn std::any::Any> {
135 Box::new(self.clone())
136 }
137 }
138 };
139
140 ($name:ident) => {
141 #[derive(Clone, Debug, Eq, PartialEq)]
142 pub struct $name;
143
144 impl $crate::Action for $name {
145 type Argument = ();
146 }
147
148 impl $crate::AnyAction for $name {
149 fn id(&self) -> std::any::TypeId {
150 std::any::TypeId::of::<$name>()
151 }
152
153 fn name(&self) -> &'static str {
154 stringify!($name)
155 }
156
157 fn as_any(&self) -> &dyn std::any::Any {
158 self
159 }
160
161 fn boxed_clone(&self) -> Box<dyn $crate::AnyAction> {
162 Box::new(self.clone())
163 }
164
165 fn boxed_clone_as_any(&self) -> Box<dyn std::any::Any> {
166 Box::new(self.clone())
167 }
168 }
169 };
170}
171
172pub struct Menu<'a> {
173 pub name: &'a str,
174 pub items: Vec<MenuItem<'a>>,
175}
176
177pub enum MenuItem<'a> {
178 Action {
179 name: &'a str,
180 keystroke: Option<&'a str>,
181 action: Box<dyn AnyAction>,
182 },
183 Separator,
184}
185
186#[derive(Clone)]
187pub struct App(Rc<RefCell<MutableAppContext>>);
188
189#[derive(Clone)]
190pub struct AsyncAppContext(Rc<RefCell<MutableAppContext>>);
191
192pub struct BackgroundAppContext(*const RefCell<MutableAppContext>);
193
194#[derive(Clone)]
195pub struct TestAppContext {
196 cx: Rc<RefCell<MutableAppContext>>,
197 foreground_platform: Rc<platform::test::ForegroundPlatform>,
198}
199
200impl App {
201 pub fn new(asset_source: impl AssetSource) -> Result<Self> {
202 let platform = platform::current::platform();
203 let foreground_platform = platform::current::foreground_platform();
204 let foreground = Rc::new(executor::Foreground::platform(platform.dispatcher())?);
205 let app = Self(Rc::new(RefCell::new(MutableAppContext::new(
206 foreground,
207 Arc::new(executor::Background::new()),
208 platform.clone(),
209 foreground_platform.clone(),
210 Arc::new(FontCache::new(platform.fonts())),
211 asset_source,
212 ))));
213
214 let cx = app.0.clone();
215 foreground_platform.on_menu_command(Box::new(move |action| {
216 let mut cx = cx.borrow_mut();
217 if let Some(key_window_id) = cx.cx.platform.key_window_id() {
218 if let Some((presenter, _)) = cx.presenters_and_platform_windows.get(&key_window_id)
219 {
220 let presenter = presenter.clone();
221 let path = presenter.borrow().dispatch_path(cx.as_ref());
222 cx.dispatch_action_any(key_window_id, &path, action);
223 } else {
224 cx.dispatch_global_action_any(action);
225 }
226 } else {
227 cx.dispatch_global_action_any(action);
228 }
229 }));
230
231 app.0.borrow_mut().weak_self = Some(Rc::downgrade(&app.0));
232 Ok(app)
233 }
234
235 pub fn on_become_active<F>(self, mut callback: F) -> Self
236 where
237 F: 'static + FnMut(&mut MutableAppContext),
238 {
239 let cx = self.0.clone();
240 self.0
241 .borrow_mut()
242 .foreground_platform
243 .on_become_active(Box::new(move || callback(&mut *cx.borrow_mut())));
244 self
245 }
246
247 pub fn on_resign_active<F>(self, mut callback: F) -> Self
248 where
249 F: 'static + FnMut(&mut MutableAppContext),
250 {
251 let cx = self.0.clone();
252 self.0
253 .borrow_mut()
254 .foreground_platform
255 .on_resign_active(Box::new(move || callback(&mut *cx.borrow_mut())));
256 self
257 }
258
259 pub fn on_event<F>(self, mut callback: F) -> Self
260 where
261 F: 'static + FnMut(Event, &mut MutableAppContext) -> bool,
262 {
263 let cx = self.0.clone();
264 self.0
265 .borrow_mut()
266 .foreground_platform
267 .on_event(Box::new(move |event| {
268 callback(event, &mut *cx.borrow_mut())
269 }));
270 self
271 }
272
273 pub fn on_open_files<F>(self, mut callback: F) -> Self
274 where
275 F: 'static + FnMut(Vec<PathBuf>, &mut MutableAppContext),
276 {
277 let cx = self.0.clone();
278 self.0
279 .borrow_mut()
280 .foreground_platform
281 .on_open_files(Box::new(move |paths| {
282 callback(paths, &mut *cx.borrow_mut())
283 }));
284 self
285 }
286
287 pub fn run<F>(self, on_finish_launching: F)
288 where
289 F: 'static + FnOnce(&mut MutableAppContext),
290 {
291 let platform = self.0.borrow().foreground_platform.clone();
292 platform.run(Box::new(move || {
293 let mut cx = self.0.borrow_mut();
294 on_finish_launching(&mut *cx);
295 }))
296 }
297
298 pub fn font_cache(&self) -> Arc<FontCache> {
299 self.0.borrow().cx.font_cache.clone()
300 }
301
302 fn update<T, F: FnOnce(&mut MutableAppContext) -> T>(&mut self, callback: F) -> T {
303 let mut state = self.0.borrow_mut();
304 state.pending_flushes += 1;
305 let result = callback(&mut *state);
306 state.flush_effects();
307 result
308 }
309}
310
311impl TestAppContext {
312 pub fn new(
313 foreground_platform: Rc<platform::test::ForegroundPlatform>,
314 platform: Arc<dyn Platform>,
315 foreground: Rc<executor::Foreground>,
316 background: Arc<executor::Background>,
317 font_cache: Arc<FontCache>,
318 first_entity_id: usize,
319 ) -> Self {
320 let mut cx = MutableAppContext::new(
321 foreground.clone(),
322 background,
323 platform,
324 foreground_platform.clone(),
325 font_cache,
326 (),
327 );
328 cx.next_entity_id = first_entity_id;
329 let cx = TestAppContext {
330 cx: Rc::new(RefCell::new(cx)),
331 foreground_platform,
332 };
333 cx.cx.borrow_mut().weak_self = Some(Rc::downgrade(&cx.cx));
334 cx
335 }
336
337 pub fn dispatch_action<A: Action>(
338 &self,
339 window_id: usize,
340 responder_chain: Vec<usize>,
341 action: A,
342 ) {
343 self.cx
344 .borrow_mut()
345 .dispatch_action_any(window_id, &responder_chain, &action);
346 }
347
348 pub fn dispatch_global_action<A: Action>(&self, action: A) {
349 self.cx.borrow_mut().dispatch_global_action(action);
350 }
351
352 pub fn dispatch_keystroke(
353 &self,
354 window_id: usize,
355 responder_chain: Vec<usize>,
356 keystroke: &Keystroke,
357 ) -> Result<bool> {
358 let mut state = self.cx.borrow_mut();
359 state.dispatch_keystroke(window_id, responder_chain, keystroke)
360 }
361
362 pub fn add_model<T, F>(&mut self, build_model: F) -> ModelHandle<T>
363 where
364 T: Entity,
365 F: FnOnce(&mut ModelContext<T>) -> T,
366 {
367 let mut state = self.cx.borrow_mut();
368 state.pending_flushes += 1;
369 let handle = state.add_model(build_model);
370 state.flush_effects();
371 handle
372 }
373
374 pub fn add_window<T, F>(&mut self, build_root_view: F) -> (usize, ViewHandle<T>)
375 where
376 T: View,
377 F: FnOnce(&mut ViewContext<T>) -> T,
378 {
379 self.cx
380 .borrow_mut()
381 .add_window(Default::default(), build_root_view)
382 }
383
384 pub fn window_ids(&self) -> Vec<usize> {
385 self.cx.borrow().window_ids().collect()
386 }
387
388 pub fn root_view<T: View>(&self, window_id: usize) -> Option<ViewHandle<T>> {
389 self.cx.borrow().root_view(window_id)
390 }
391
392 pub fn add_view<T, F>(&mut self, window_id: usize, build_view: F) -> ViewHandle<T>
393 where
394 T: View,
395 F: FnOnce(&mut ViewContext<T>) -> T,
396 {
397 let mut state = self.cx.borrow_mut();
398 state.pending_flushes += 1;
399 let handle = state.add_view(window_id, build_view);
400 state.flush_effects();
401 handle
402 }
403
404 pub fn add_option_view<T, F>(
405 &mut self,
406 window_id: usize,
407 build_view: F,
408 ) -> Option<ViewHandle<T>>
409 where
410 T: View,
411 F: FnOnce(&mut ViewContext<T>) -> Option<T>,
412 {
413 let mut state = self.cx.borrow_mut();
414 state.pending_flushes += 1;
415 let handle = state.add_option_view(window_id, build_view);
416 state.flush_effects();
417 handle
418 }
419
420 pub fn read<T, F: FnOnce(&AppContext) -> T>(&self, callback: F) -> T {
421 callback(self.cx.borrow().as_ref())
422 }
423
424 pub fn update<T, F: FnOnce(&mut MutableAppContext) -> T>(&mut self, callback: F) -> T {
425 let mut state = self.cx.borrow_mut();
426 // Don't increment pending flushes in order to effects to be flushed before the callback
427 // completes, which is helpful in tests.
428 let result = callback(&mut *state);
429 // Flush effects after the callback just in case there are any. This can happen in edge
430 // cases such as the closure dropping handles.
431 state.flush_effects();
432 result
433 }
434
435 pub fn to_async(&self) -> AsyncAppContext {
436 AsyncAppContext(self.cx.clone())
437 }
438
439 pub fn font_cache(&self) -> Arc<FontCache> {
440 self.cx.borrow().cx.font_cache.clone()
441 }
442
443 pub fn platform(&self) -> Arc<dyn platform::Platform> {
444 self.cx.borrow().cx.platform.clone()
445 }
446
447 pub fn foreground(&self) -> Rc<executor::Foreground> {
448 self.cx.borrow().foreground().clone()
449 }
450
451 pub fn background(&self) -> Arc<executor::Background> {
452 self.cx.borrow().background().clone()
453 }
454
455 pub fn simulate_new_path_selection(&self, result: impl FnOnce(PathBuf) -> Option<PathBuf>) {
456 self.foreground_platform.simulate_new_path_selection(result);
457 }
458
459 pub fn did_prompt_for_new_path(&self) -> bool {
460 self.foreground_platform.as_ref().did_prompt_for_new_path()
461 }
462
463 pub fn simulate_prompt_answer(&self, window_id: usize, answer: usize) {
464 let mut state = self.cx.borrow_mut();
465 let (_, window) = state
466 .presenters_and_platform_windows
467 .get_mut(&window_id)
468 .unwrap();
469 let test_window = window
470 .as_any_mut()
471 .downcast_mut::<platform::test::Window>()
472 .unwrap();
473 let callback = test_window
474 .last_prompt
475 .take()
476 .expect("prompt was not called");
477 (callback)(answer);
478 }
479}
480
481impl AsyncAppContext {
482 pub fn spawn<F, Fut, T>(&self, f: F) -> Task<T>
483 where
484 F: FnOnce(AsyncAppContext) -> Fut,
485 Fut: 'static + Future<Output = T>,
486 T: 'static,
487 {
488 self.0.borrow().foreground.spawn(f(self.clone()))
489 }
490
491 pub fn read<T, F: FnOnce(&AppContext) -> T>(&mut self, callback: F) -> T {
492 callback(self.0.borrow().as_ref())
493 }
494
495 pub fn update<T, F: FnOnce(&mut MutableAppContext) -> T>(&mut self, callback: F) -> T {
496 let mut state = self.0.borrow_mut();
497 state.pending_flushes += 1;
498 let result = callback(&mut *state);
499 state.flush_effects();
500 result
501 }
502
503 pub fn add_model<T, F>(&mut self, build_model: F) -> ModelHandle<T>
504 where
505 T: Entity,
506 F: FnOnce(&mut ModelContext<T>) -> T,
507 {
508 self.update(|cx| cx.add_model(build_model))
509 }
510
511 pub fn platform(&self) -> Arc<dyn Platform> {
512 self.0.borrow().platform()
513 }
514
515 pub fn foreground(&self) -> Rc<executor::Foreground> {
516 self.0.borrow().foreground.clone()
517 }
518
519 pub fn background(&self) -> Arc<executor::Background> {
520 self.0.borrow().cx.background.clone()
521 }
522}
523
524impl UpdateModel for AsyncAppContext {
525 fn update_model<T, F, S>(&mut self, handle: &ModelHandle<T>, update: F) -> S
526 where
527 T: Entity,
528 F: FnOnce(&mut T, &mut ModelContext<T>) -> S,
529 {
530 let mut state = self.0.borrow_mut();
531 state.pending_flushes += 1;
532 let result = state.update_model(handle, update);
533 state.flush_effects();
534 result
535 }
536}
537
538impl UpgradeModelHandle for AsyncAppContext {
539 fn upgrade_model_handle<T: Entity>(
540 &self,
541 handle: WeakModelHandle<T>,
542 ) -> Option<ModelHandle<T>> {
543 self.0.borrow_mut().upgrade_model_handle(handle)
544 }
545}
546
547impl ReadModelWith for AsyncAppContext {
548 fn read_model_with<E: Entity, F: FnOnce(&E, &AppContext) -> T, T>(
549 &self,
550 handle: &ModelHandle<E>,
551 read: F,
552 ) -> T {
553 let cx = self.0.borrow();
554 let cx = cx.as_ref();
555 read(handle.read(cx), cx)
556 }
557}
558
559impl UpdateView for AsyncAppContext {
560 fn update_view<T, F, S>(&mut self, handle: &ViewHandle<T>, update: F) -> S
561 where
562 T: View,
563 F: FnOnce(&mut T, &mut ViewContext<T>) -> S,
564 {
565 let mut state = self.0.borrow_mut();
566 state.pending_flushes += 1;
567 let result = state.update_view(handle, update);
568 state.flush_effects();
569 result
570 }
571}
572
573impl ReadViewWith for AsyncAppContext {
574 fn read_view_with<V, F, T>(&self, handle: &ViewHandle<V>, read: F) -> T
575 where
576 V: View,
577 F: FnOnce(&V, &AppContext) -> T,
578 {
579 let cx = self.0.borrow();
580 let cx = cx.as_ref();
581 read(handle.read(cx), cx)
582 }
583}
584
585impl UpdateModel for TestAppContext {
586 fn update_model<T, F, S>(&mut self, handle: &ModelHandle<T>, update: F) -> S
587 where
588 T: Entity,
589 F: FnOnce(&mut T, &mut ModelContext<T>) -> S,
590 {
591 let mut state = self.cx.borrow_mut();
592 state.pending_flushes += 1;
593 let result = state.update_model(handle, update);
594 state.flush_effects();
595 result
596 }
597}
598
599impl ReadModelWith for TestAppContext {
600 fn read_model_with<E: Entity, F: FnOnce(&E, &AppContext) -> T, T>(
601 &self,
602 handle: &ModelHandle<E>,
603 read: F,
604 ) -> T {
605 let cx = self.cx.borrow();
606 let cx = cx.as_ref();
607 read(handle.read(cx), cx)
608 }
609}
610
611impl UpdateView for TestAppContext {
612 fn update_view<T, F, S>(&mut self, handle: &ViewHandle<T>, update: F) -> S
613 where
614 T: View,
615 F: FnOnce(&mut T, &mut ViewContext<T>) -> S,
616 {
617 let mut state = self.cx.borrow_mut();
618 state.pending_flushes += 1;
619 let result = state.update_view(handle, update);
620 state.flush_effects();
621 result
622 }
623}
624
625impl ReadViewWith for TestAppContext {
626 fn read_view_with<V, F, T>(&self, handle: &ViewHandle<V>, read: F) -> T
627 where
628 V: View,
629 F: FnOnce(&V, &AppContext) -> T,
630 {
631 let cx = self.cx.borrow();
632 let cx = cx.as_ref();
633 read(handle.read(cx), cx)
634 }
635}
636
637type ActionCallback =
638 dyn FnMut(&mut dyn AnyView, &dyn AnyAction, &mut MutableAppContext, usize, usize) -> bool;
639
640type GlobalActionCallback = dyn FnMut(&dyn AnyAction, &mut MutableAppContext);
641
642pub struct MutableAppContext {
643 weak_self: Option<rc::Weak<RefCell<Self>>>,
644 foreground_platform: Rc<dyn platform::ForegroundPlatform>,
645 assets: Arc<AssetCache>,
646 cx: AppContext,
647 actions: HashMap<TypeId, HashMap<TypeId, Vec<Box<ActionCallback>>>>,
648 global_actions: HashMap<TypeId, Vec<Box<GlobalActionCallback>>>,
649 keystroke_matcher: keymap::Matcher,
650 next_entity_id: usize,
651 next_window_id: usize,
652 subscriptions: HashMap<usize, Vec<Box<dyn FnMut(&dyn Any, &mut MutableAppContext) -> bool>>>,
653 observations: HashMap<usize, Vec<Box<dyn FnMut(&mut MutableAppContext) -> bool>>>,
654 presenters_and_platform_windows:
655 HashMap<usize, (Rc<RefCell<Presenter>>, Box<dyn platform::Window>)>,
656 debug_elements_callbacks: HashMap<usize, Box<dyn Fn(&AppContext) -> crate::json::Value>>,
657 foreground: Rc<executor::Foreground>,
658 pending_effects: VecDeque<Effect>,
659 pending_flushes: usize,
660 flushing_effects: bool,
661}
662
663impl MutableAppContext {
664 fn new(
665 foreground: Rc<executor::Foreground>,
666 background: Arc<executor::Background>,
667 platform: Arc<dyn platform::Platform>,
668 foreground_platform: Rc<dyn platform::ForegroundPlatform>,
669 font_cache: Arc<FontCache>,
670 asset_source: impl AssetSource,
671 ) -> Self {
672 Self {
673 weak_self: None,
674 foreground_platform,
675 assets: Arc::new(AssetCache::new(asset_source)),
676 cx: AppContext {
677 models: Default::default(),
678 views: Default::default(),
679 windows: Default::default(),
680 values: Default::default(),
681 ref_counts: Arc::new(Mutex::new(RefCounts::default())),
682 background,
683 font_cache,
684 platform,
685 },
686 actions: HashMap::new(),
687 global_actions: HashMap::new(),
688 keystroke_matcher: keymap::Matcher::default(),
689 next_entity_id: 0,
690 next_window_id: 0,
691 subscriptions: HashMap::new(),
692 observations: HashMap::new(),
693 presenters_and_platform_windows: HashMap::new(),
694 debug_elements_callbacks: HashMap::new(),
695 foreground,
696 pending_effects: VecDeque::new(),
697 pending_flushes: 0,
698 flushing_effects: false,
699 }
700 }
701
702 pub fn upgrade(&self) -> App {
703 App(self.weak_self.as_ref().unwrap().upgrade().unwrap())
704 }
705
706 pub fn platform(&self) -> Arc<dyn platform::Platform> {
707 self.cx.platform.clone()
708 }
709
710 pub fn font_cache(&self) -> &Arc<FontCache> {
711 &self.cx.font_cache
712 }
713
714 pub fn foreground(&self) -> &Rc<executor::Foreground> {
715 &self.foreground
716 }
717
718 pub fn background(&self) -> &Arc<executor::Background> {
719 &self.cx.background
720 }
721
722 pub fn on_debug_elements<F>(&mut self, window_id: usize, callback: F)
723 where
724 F: 'static + Fn(&AppContext) -> crate::json::Value,
725 {
726 self.debug_elements_callbacks
727 .insert(window_id, Box::new(callback));
728 }
729
730 pub fn debug_elements(&self, window_id: usize) -> Option<crate::json::Value> {
731 self.debug_elements_callbacks
732 .get(&window_id)
733 .map(|debug_elements| debug_elements(&self.cx))
734 }
735
736 pub fn add_action<A, V, F>(&mut self, mut handler: F)
737 where
738 A: Action,
739 V: View,
740 F: 'static + FnMut(&mut V, &A, &mut ViewContext<V>),
741 {
742 let handler = Box::new(
743 move |view: &mut dyn AnyView,
744 action: &dyn AnyAction,
745 cx: &mut MutableAppContext,
746 window_id: usize,
747 view_id: usize| {
748 let action = action.as_any().downcast_ref().unwrap();
749 let mut cx = ViewContext::new(cx, window_id, view_id);
750 handler(
751 view.as_any_mut()
752 .downcast_mut()
753 .expect("downcast is type safe"),
754 action,
755 &mut cx,
756 );
757 cx.halt_action_dispatch
758 },
759 );
760
761 self.actions
762 .entry(TypeId::of::<V>())
763 .or_default()
764 .entry(TypeId::of::<A>())
765 .or_default()
766 .push(handler);
767 }
768
769 pub fn add_global_action<A, F>(&mut self, mut handler: F)
770 where
771 A: Action,
772 F: 'static + FnMut(&A, &mut MutableAppContext),
773 {
774 let handler = Box::new(move |action: &dyn AnyAction, cx: &mut MutableAppContext| {
775 let action = action.as_any().downcast_ref().unwrap();
776 handler(action, cx);
777 });
778
779 self.global_actions
780 .entry(TypeId::of::<A>())
781 .or_default()
782 .push(handler);
783 }
784
785 pub fn window_ids(&self) -> impl Iterator<Item = usize> + '_ {
786 self.cx.windows.keys().cloned()
787 }
788
789 pub fn root_view<T: View>(&self, window_id: usize) -> Option<ViewHandle<T>> {
790 self.cx
791 .windows
792 .get(&window_id)
793 .and_then(|window| window.root_view.clone().downcast::<T>())
794 }
795
796 pub fn root_view_id(&self, window_id: usize) -> Option<usize> {
797 self.cx.root_view_id(window_id)
798 }
799
800 pub fn focused_view_id(&self, window_id: usize) -> Option<usize> {
801 self.cx.focused_view_id(window_id)
802 }
803
804 pub fn render_views(
805 &self,
806 window_id: usize,
807 titlebar_height: f32,
808 ) -> HashMap<usize, ElementBox> {
809 self.cx.render_views(window_id, titlebar_height)
810 }
811
812 pub fn update<T, F: FnOnce() -> T>(&mut self, callback: F) -> T {
813 self.pending_flushes += 1;
814 let result = callback();
815 self.flush_effects();
816 result
817 }
818
819 pub fn set_menus(&mut self, menus: Vec<Menu>) {
820 self.foreground_platform.set_menus(menus);
821 }
822
823 fn prompt<F>(
824 &self,
825 window_id: usize,
826 level: PromptLevel,
827 msg: &str,
828 answers: &[&str],
829 done_fn: F,
830 ) where
831 F: 'static + FnOnce(usize, &mut MutableAppContext),
832 {
833 let app = self.weak_self.as_ref().unwrap().upgrade().unwrap();
834 let foreground = self.foreground.clone();
835 let (_, window) = &self.presenters_and_platform_windows[&window_id];
836 window.prompt(
837 level,
838 msg,
839 answers,
840 Box::new(move |answer| {
841 foreground
842 .spawn(async move { (done_fn)(answer, &mut *app.borrow_mut()) })
843 .detach();
844 }),
845 );
846 }
847
848 pub fn prompt_for_paths<F>(&self, options: PathPromptOptions, done_fn: F)
849 where
850 F: 'static + FnOnce(Option<Vec<PathBuf>>, &mut MutableAppContext),
851 {
852 let app = self.weak_self.as_ref().unwrap().upgrade().unwrap();
853 let foreground = self.foreground.clone();
854 self.foreground_platform.prompt_for_paths(
855 options,
856 Box::new(move |paths| {
857 foreground
858 .spawn(async move { (done_fn)(paths, &mut *app.borrow_mut()) })
859 .detach();
860 }),
861 );
862 }
863
864 pub fn prompt_for_new_path<F>(&self, directory: &Path, done_fn: F)
865 where
866 F: 'static + FnOnce(Option<PathBuf>, &mut MutableAppContext),
867 {
868 let app = self.weak_self.as_ref().unwrap().upgrade().unwrap();
869 let foreground = self.foreground.clone();
870 self.foreground_platform.prompt_for_new_path(
871 directory,
872 Box::new(move |path| {
873 foreground
874 .spawn(async move { (done_fn)(path, &mut *app.borrow_mut()) })
875 .detach();
876 }),
877 );
878 }
879
880 pub fn subscribe<E, H, F>(&mut self, handle: &H, mut callback: F)
881 where
882 E: Entity,
883 E::Event: 'static,
884 H: Handle<E>,
885 F: 'static + FnMut(H, &E::Event, &mut Self),
886 {
887 self.subscribe_internal(handle, move |handle, event, cx| {
888 callback(handle, event, cx);
889 true
890 })
891 }
892
893 fn observe<E, H, F>(&mut self, handle: &H, mut callback: F)
894 where
895 E: Entity,
896 E::Event: 'static,
897 H: Handle<E>,
898 F: 'static + FnMut(H, &mut Self),
899 {
900 self.observe_internal(handle, move |handle, cx| {
901 callback(handle, cx);
902 true
903 })
904 }
905
906 pub fn subscribe_internal<E, H, F>(&mut self, handle: &H, mut callback: F)
907 where
908 E: Entity,
909 E::Event: 'static,
910 H: Handle<E>,
911 F: 'static + FnMut(H, &E::Event, &mut Self) -> bool,
912 {
913 let emitter = handle.downgrade();
914 self.subscriptions
915 .entry(handle.id())
916 .or_default()
917 .push(Box::new(move |payload, cx| {
918 if let Some(emitter) = H::upgrade_from(&emitter, cx.as_ref()) {
919 let payload = payload.downcast_ref().expect("downcast is type safe");
920 callback(emitter, payload, cx)
921 } else {
922 false
923 }
924 }))
925 }
926
927 fn observe_internal<E, H, F>(&mut self, handle: &H, mut callback: F)
928 where
929 E: Entity,
930 E::Event: 'static,
931 H: Handle<E>,
932 F: 'static + FnMut(H, &mut Self) -> bool,
933 {
934 let observed = handle.downgrade();
935 self.observations
936 .entry(handle.id())
937 .or_default()
938 .push(Box::new(move |cx| {
939 if let Some(observed) = H::upgrade_from(&observed, cx) {
940 callback(observed, cx)
941 } else {
942 false
943 }
944 }))
945 }
946
947 pub(crate) fn notify_view(&mut self, window_id: usize, view_id: usize) {
948 self.pending_effects
949 .push_back(Effect::ViewNotification { window_id, view_id });
950 }
951
952 pub(crate) fn notify_all_views(&mut self) {
953 let notifications = self
954 .views
955 .keys()
956 .copied()
957 .map(|(window_id, view_id)| Effect::ViewNotification { window_id, view_id })
958 .collect::<Vec<_>>();
959 self.pending_effects.extend(notifications);
960 }
961
962 pub fn dispatch_action<A: Action>(
963 &mut self,
964 window_id: usize,
965 responder_chain: Vec<usize>,
966 action: &A,
967 ) {
968 self.dispatch_action_any(window_id, &responder_chain, action);
969 }
970
971 pub(crate) fn dispatch_action_any(
972 &mut self,
973 window_id: usize,
974 path: &[usize],
975 action: &dyn AnyAction,
976 ) -> bool {
977 self.pending_flushes += 1;
978 let mut halted_dispatch = false;
979
980 for view_id in path.iter().rev() {
981 if let Some(mut view) = self.cx.views.remove(&(window_id, *view_id)) {
982 let type_id = view.as_any().type_id();
983
984 if let Some((name, mut handlers)) = self
985 .actions
986 .get_mut(&type_id)
987 .and_then(|h| h.remove_entry(&action.id()))
988 {
989 for handler in handlers.iter_mut().rev() {
990 let halt_dispatch =
991 handler(view.as_mut(), action, self, window_id, *view_id);
992 if halt_dispatch {
993 halted_dispatch = true;
994 break;
995 }
996 }
997 self.actions
998 .get_mut(&type_id)
999 .unwrap()
1000 .insert(name, handlers);
1001 }
1002
1003 self.cx.views.insert((window_id, *view_id), view);
1004
1005 if halted_dispatch {
1006 break;
1007 }
1008 }
1009 }
1010
1011 if !halted_dispatch {
1012 self.dispatch_global_action_any(action);
1013 }
1014
1015 self.flush_effects();
1016 halted_dispatch
1017 }
1018
1019 pub fn dispatch_global_action<A: Action>(&mut self, action: A) {
1020 self.dispatch_global_action_any(&action);
1021 }
1022
1023 fn dispatch_global_action_any(&mut self, action: &dyn AnyAction) {
1024 if let Some((name, mut handlers)) = self.global_actions.remove_entry(&action.id()) {
1025 self.pending_flushes += 1;
1026 for handler in handlers.iter_mut().rev() {
1027 handler(action, self);
1028 }
1029 self.global_actions.insert(name, handlers);
1030 self.flush_effects();
1031 }
1032 }
1033
1034 pub fn add_bindings<T: IntoIterator<Item = keymap::Binding>>(&mut self, bindings: T) {
1035 self.keystroke_matcher.add_bindings(bindings);
1036 }
1037
1038 pub fn dispatch_keystroke(
1039 &mut self,
1040 window_id: usize,
1041 responder_chain: Vec<usize>,
1042 keystroke: &Keystroke,
1043 ) -> Result<bool> {
1044 let mut context_chain = Vec::new();
1045 let mut context = keymap::Context::default();
1046 for view_id in &responder_chain {
1047 if let Some(view) = self.cx.views.get(&(window_id, *view_id)) {
1048 context.extend(view.keymap_context(self.as_ref()));
1049 context_chain.push(context.clone());
1050 } else {
1051 return Err(anyhow!(
1052 "View {} in responder chain does not exist",
1053 view_id
1054 ));
1055 }
1056 }
1057
1058 let mut pending = false;
1059 for (i, cx) in context_chain.iter().enumerate().rev() {
1060 match self
1061 .keystroke_matcher
1062 .push_keystroke(keystroke.clone(), responder_chain[i], cx)
1063 {
1064 MatchResult::None => {}
1065 MatchResult::Pending => pending = true,
1066 MatchResult::Action(action) => {
1067 if self.dispatch_action_any(window_id, &responder_chain[0..=i], action.as_ref())
1068 {
1069 return Ok(true);
1070 }
1071 }
1072 }
1073 }
1074
1075 Ok(pending)
1076 }
1077
1078 pub fn add_model<T, F>(&mut self, build_model: F) -> ModelHandle<T>
1079 where
1080 T: Entity,
1081 F: FnOnce(&mut ModelContext<T>) -> T,
1082 {
1083 self.pending_flushes += 1;
1084 let model_id = post_inc(&mut self.next_entity_id);
1085 let handle = ModelHandle::new(model_id, &self.cx.ref_counts);
1086 let mut cx = ModelContext::new(self, model_id);
1087 let model = build_model(&mut cx);
1088 self.cx.models.insert(model_id, Box::new(model));
1089 self.flush_effects();
1090 handle
1091 }
1092
1093 pub fn add_window<T, F>(
1094 &mut self,
1095 window_options: WindowOptions,
1096 build_root_view: F,
1097 ) -> (usize, ViewHandle<T>)
1098 where
1099 T: View,
1100 F: FnOnce(&mut ViewContext<T>) -> T,
1101 {
1102 self.pending_flushes += 1;
1103 let window_id = post_inc(&mut self.next_window_id);
1104 let root_view = self.add_view(window_id, build_root_view);
1105
1106 self.cx.windows.insert(
1107 window_id,
1108 Window {
1109 root_view: root_view.clone().into(),
1110 focused_view_id: root_view.id(),
1111 invalidation: None,
1112 },
1113 );
1114 self.open_platform_window(window_id, window_options);
1115 root_view.update(self, |view, cx| {
1116 view.on_focus(cx);
1117 cx.notify();
1118 });
1119 self.flush_effects();
1120
1121 (window_id, root_view)
1122 }
1123
1124 pub fn remove_window(&mut self, window_id: usize) {
1125 self.cx.windows.remove(&window_id);
1126 self.presenters_and_platform_windows.remove(&window_id);
1127 self.remove_dropped_entities();
1128 }
1129
1130 fn open_platform_window(&mut self, window_id: usize, window_options: WindowOptions) {
1131 let mut window =
1132 self.cx
1133 .platform
1134 .open_window(window_id, window_options, self.foreground.clone());
1135 let presenter = Rc::new(RefCell::new(
1136 self.build_presenter(window_id, window.titlebar_height()),
1137 ));
1138
1139 {
1140 let mut app = self.upgrade();
1141 let presenter = presenter.clone();
1142 window.on_event(Box::new(move |event| {
1143 app.update(|cx| {
1144 if let Event::KeyDown { keystroke, .. } = &event {
1145 if cx
1146 .dispatch_keystroke(
1147 window_id,
1148 presenter.borrow().dispatch_path(cx.as_ref()),
1149 keystroke,
1150 )
1151 .unwrap()
1152 {
1153 return;
1154 }
1155 }
1156
1157 presenter.borrow_mut().dispatch_event(event, cx);
1158 })
1159 }));
1160 }
1161
1162 {
1163 let mut app = self.upgrade();
1164 let presenter = presenter.clone();
1165 window.on_resize(Box::new(move |window| {
1166 app.update(|cx| {
1167 let scene = presenter.borrow_mut().build_scene(
1168 window.size(),
1169 window.scale_factor(),
1170 cx,
1171 );
1172 window.present_scene(scene);
1173 })
1174 }));
1175 }
1176
1177 {
1178 let mut app = self.upgrade();
1179 window.on_close(Box::new(move || {
1180 app.update(|cx| cx.remove_window(window_id));
1181 }));
1182 }
1183
1184 self.presenters_and_platform_windows
1185 .insert(window_id, (presenter.clone(), window));
1186
1187 self.on_debug_elements(window_id, move |cx| {
1188 presenter.borrow().debug_elements(cx).unwrap()
1189 });
1190 }
1191
1192 pub fn build_presenter(&self, window_id: usize, titlebar_height: f32) -> Presenter {
1193 Presenter::new(
1194 window_id,
1195 titlebar_height,
1196 self.cx.font_cache.clone(),
1197 TextLayoutCache::new(self.cx.platform.fonts()),
1198 self.assets.clone(),
1199 self,
1200 )
1201 }
1202
1203 pub fn add_view<T, F>(&mut self, window_id: usize, build_view: F) -> ViewHandle<T>
1204 where
1205 T: View,
1206 F: FnOnce(&mut ViewContext<T>) -> T,
1207 {
1208 self.add_option_view(window_id, |cx| Some(build_view(cx)))
1209 .unwrap()
1210 }
1211
1212 pub fn add_option_view<T, F>(
1213 &mut self,
1214 window_id: usize,
1215 build_view: F,
1216 ) -> Option<ViewHandle<T>>
1217 where
1218 T: View,
1219 F: FnOnce(&mut ViewContext<T>) -> Option<T>,
1220 {
1221 let view_id = post_inc(&mut self.next_entity_id);
1222 self.pending_flushes += 1;
1223 let handle = ViewHandle::new(window_id, view_id, &self.cx.ref_counts);
1224 let mut cx = ViewContext::new(self, window_id, view_id);
1225 let handle = if let Some(view) = build_view(&mut cx) {
1226 self.cx.views.insert((window_id, view_id), Box::new(view));
1227 if let Some(window) = self.cx.windows.get_mut(&window_id) {
1228 window
1229 .invalidation
1230 .get_or_insert_with(Default::default)
1231 .updated
1232 .insert(view_id);
1233 }
1234 Some(handle)
1235 } else {
1236 None
1237 };
1238 self.flush_effects();
1239 handle
1240 }
1241
1242 fn remove_dropped_entities(&mut self) {
1243 loop {
1244 let (dropped_models, dropped_views, dropped_values) =
1245 self.cx.ref_counts.lock().take_dropped();
1246 if dropped_models.is_empty() && dropped_views.is_empty() && dropped_values.is_empty() {
1247 break;
1248 }
1249
1250 for model_id in dropped_models {
1251 self.subscriptions.remove(&model_id);
1252 self.observations.remove(&model_id);
1253 let mut model = self.cx.models.remove(&model_id).unwrap();
1254 model.release(self);
1255 }
1256
1257 for (window_id, view_id) in dropped_views {
1258 self.subscriptions.remove(&view_id);
1259 self.observations.remove(&view_id);
1260 let mut view = self.cx.views.remove(&(window_id, view_id)).unwrap();
1261 view.release(self);
1262 let change_focus_to = self.cx.windows.get_mut(&window_id).and_then(|window| {
1263 window
1264 .invalidation
1265 .get_or_insert_with(Default::default)
1266 .removed
1267 .push(view_id);
1268 if window.focused_view_id == view_id {
1269 Some(window.root_view.id())
1270 } else {
1271 None
1272 }
1273 });
1274
1275 if let Some(view_id) = change_focus_to {
1276 self.focus(window_id, view_id);
1277 }
1278 }
1279
1280 let mut values = self.cx.values.write();
1281 for key in dropped_values {
1282 values.remove(&key);
1283 }
1284 }
1285 }
1286
1287 fn flush_effects(&mut self) {
1288 self.pending_flushes = self.pending_flushes.saturating_sub(1);
1289
1290 if !self.flushing_effects && self.pending_flushes == 0 {
1291 self.flushing_effects = true;
1292
1293 loop {
1294 if let Some(effect) = self.pending_effects.pop_front() {
1295 match effect {
1296 Effect::Event { entity_id, payload } => self.emit_event(entity_id, payload),
1297 Effect::ModelNotification { model_id } => {
1298 self.notify_model_observers(model_id)
1299 }
1300 Effect::ViewNotification { window_id, view_id } => {
1301 self.notify_view_observers(window_id, view_id)
1302 }
1303 Effect::Focus { window_id, view_id } => {
1304 self.focus(window_id, view_id);
1305 }
1306 }
1307 self.remove_dropped_entities();
1308 } else {
1309 self.remove_dropped_entities();
1310 self.update_windows();
1311
1312 if self.pending_effects.is_empty() {
1313 self.flushing_effects = false;
1314 break;
1315 }
1316 }
1317 }
1318 }
1319 }
1320
1321 fn update_windows(&mut self) {
1322 let mut invalidations = HashMap::new();
1323 for (window_id, window) in &mut self.cx.windows {
1324 if let Some(invalidation) = window.invalidation.take() {
1325 invalidations.insert(*window_id, invalidation);
1326 }
1327 }
1328
1329 for (window_id, invalidation) in invalidations {
1330 if let Some((presenter, mut window)) =
1331 self.presenters_and_platform_windows.remove(&window_id)
1332 {
1333 {
1334 let mut presenter = presenter.borrow_mut();
1335 presenter.invalidate(invalidation, self.as_ref());
1336 let scene = presenter.build_scene(window.size(), window.scale_factor(), self);
1337 window.present_scene(scene);
1338 }
1339 self.presenters_and_platform_windows
1340 .insert(window_id, (presenter, window));
1341 }
1342 }
1343 }
1344
1345 fn emit_event(&mut self, entity_id: usize, payload: Box<dyn Any>) {
1346 if let Some(callbacks) = self.subscriptions.remove(&entity_id) {
1347 for mut callback in callbacks {
1348 let alive = callback(payload.as_ref(), self);
1349 if alive {
1350 self.subscriptions
1351 .entry(entity_id)
1352 .or_default()
1353 .push(callback);
1354 }
1355 }
1356 }
1357 }
1358
1359 fn notify_model_observers(&mut self, observed_id: usize) {
1360 if let Some(callbacks) = self.observations.remove(&observed_id) {
1361 if self.cx.models.contains_key(&observed_id) {
1362 for mut callback in callbacks {
1363 let alive = callback(self);
1364 if alive {
1365 self.observations
1366 .entry(observed_id)
1367 .or_default()
1368 .push(callback);
1369 }
1370 }
1371 }
1372 }
1373 }
1374
1375 fn notify_view_observers(&mut self, observed_window_id: usize, observed_view_id: usize) {
1376 if let Some(window) = self.cx.windows.get_mut(&observed_window_id) {
1377 window
1378 .invalidation
1379 .get_or_insert_with(Default::default)
1380 .updated
1381 .insert(observed_view_id);
1382 }
1383
1384 if let Some(callbacks) = self.observations.remove(&observed_view_id) {
1385 if self
1386 .cx
1387 .views
1388 .contains_key(&(observed_window_id, observed_view_id))
1389 {
1390 for mut callback in callbacks {
1391 let alive = callback(self);
1392 if alive {
1393 self.observations
1394 .entry(observed_view_id)
1395 .or_default()
1396 .push(callback);
1397 }
1398 }
1399 }
1400 }
1401 }
1402
1403 fn focus(&mut self, window_id: usize, focused_id: usize) {
1404 if self
1405 .cx
1406 .windows
1407 .get(&window_id)
1408 .map(|w| w.focused_view_id)
1409 .map_or(false, |cur_focused| cur_focused == focused_id)
1410 {
1411 return;
1412 }
1413
1414 self.pending_flushes += 1;
1415
1416 let blurred_id = self.cx.windows.get_mut(&window_id).map(|window| {
1417 let blurred_id = window.focused_view_id;
1418 window.focused_view_id = focused_id;
1419 blurred_id
1420 });
1421
1422 if let Some(blurred_id) = blurred_id {
1423 if let Some(mut blurred_view) = self.cx.views.remove(&(window_id, blurred_id)) {
1424 blurred_view.on_blur(self, window_id, blurred_id);
1425 self.cx.views.insert((window_id, blurred_id), blurred_view);
1426 }
1427 }
1428
1429 if let Some(mut focused_view) = self.cx.views.remove(&(window_id, focused_id)) {
1430 focused_view.on_focus(self, window_id, focused_id);
1431 self.cx.views.insert((window_id, focused_id), focused_view);
1432 }
1433
1434 self.flush_effects();
1435 }
1436
1437 pub fn spawn<F, Fut, T>(&self, f: F) -> Task<T>
1438 where
1439 F: FnOnce(AsyncAppContext) -> Fut,
1440 Fut: 'static + Future<Output = T>,
1441 T: 'static,
1442 {
1443 let cx = self.to_async();
1444 self.foreground.spawn(f(cx))
1445 }
1446
1447 pub fn to_async(&self) -> AsyncAppContext {
1448 AsyncAppContext(self.weak_self.as_ref().unwrap().upgrade().unwrap())
1449 }
1450
1451 pub fn write_to_clipboard(&self, item: ClipboardItem) {
1452 self.cx.platform.write_to_clipboard(item);
1453 }
1454
1455 pub fn read_from_clipboard(&self) -> Option<ClipboardItem> {
1456 self.cx.platform.read_from_clipboard()
1457 }
1458}
1459
1460impl ReadModel for MutableAppContext {
1461 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
1462 if let Some(model) = self.cx.models.get(&handle.model_id) {
1463 model
1464 .as_any()
1465 .downcast_ref()
1466 .expect("downcast is type safe")
1467 } else {
1468 panic!("circular model reference");
1469 }
1470 }
1471}
1472
1473impl UpdateModel for MutableAppContext {
1474 fn update_model<T, F, S>(&mut self, handle: &ModelHandle<T>, update: F) -> S
1475 where
1476 T: Entity,
1477 F: FnOnce(&mut T, &mut ModelContext<T>) -> S,
1478 {
1479 if let Some(mut model) = self.cx.models.remove(&handle.model_id) {
1480 self.pending_flushes += 1;
1481 let mut cx = ModelContext::new(self, handle.model_id);
1482 let result = update(
1483 model
1484 .as_any_mut()
1485 .downcast_mut()
1486 .expect("downcast is type safe"),
1487 &mut cx,
1488 );
1489 self.cx.models.insert(handle.model_id, model);
1490 self.flush_effects();
1491 result
1492 } else {
1493 panic!("circular model update");
1494 }
1495 }
1496}
1497
1498impl UpgradeModelHandle for MutableAppContext {
1499 fn upgrade_model_handle<T: Entity>(
1500 &self,
1501 handle: WeakModelHandle<T>,
1502 ) -> Option<ModelHandle<T>> {
1503 self.cx.upgrade_model_handle(handle)
1504 }
1505}
1506
1507impl ReadView for MutableAppContext {
1508 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
1509 if let Some(view) = self.cx.views.get(&(handle.window_id, handle.view_id)) {
1510 view.as_any().downcast_ref().expect("downcast is type safe")
1511 } else {
1512 panic!("circular view reference");
1513 }
1514 }
1515}
1516
1517impl UpdateView for MutableAppContext {
1518 fn update_view<T, F, S>(&mut self, handle: &ViewHandle<T>, update: F) -> S
1519 where
1520 T: View,
1521 F: FnOnce(&mut T, &mut ViewContext<T>) -> S,
1522 {
1523 self.pending_flushes += 1;
1524 let mut view = self
1525 .cx
1526 .views
1527 .remove(&(handle.window_id, handle.view_id))
1528 .expect("circular view update");
1529
1530 let mut cx = ViewContext::new(self, handle.window_id, handle.view_id);
1531 let result = update(
1532 view.as_any_mut()
1533 .downcast_mut()
1534 .expect("downcast is type safe"),
1535 &mut cx,
1536 );
1537 self.cx
1538 .views
1539 .insert((handle.window_id, handle.view_id), view);
1540 self.flush_effects();
1541 result
1542 }
1543}
1544
1545impl AsRef<AppContext> for MutableAppContext {
1546 fn as_ref(&self) -> &AppContext {
1547 &self.cx
1548 }
1549}
1550
1551impl Deref for MutableAppContext {
1552 type Target = AppContext;
1553
1554 fn deref(&self) -> &Self::Target {
1555 &self.cx
1556 }
1557}
1558
1559pub struct AppContext {
1560 models: HashMap<usize, Box<dyn AnyModel>>,
1561 views: HashMap<(usize, usize), Box<dyn AnyView>>,
1562 windows: HashMap<usize, Window>,
1563 values: RwLock<HashMap<(TypeId, usize), Box<dyn Any>>>,
1564 background: Arc<executor::Background>,
1565 ref_counts: Arc<Mutex<RefCounts>>,
1566 font_cache: Arc<FontCache>,
1567 platform: Arc<dyn Platform>,
1568}
1569
1570impl AppContext {
1571 pub fn root_view_id(&self, window_id: usize) -> Option<usize> {
1572 self.windows
1573 .get(&window_id)
1574 .map(|window| window.root_view.id())
1575 }
1576
1577 pub fn focused_view_id(&self, window_id: usize) -> Option<usize> {
1578 self.windows
1579 .get(&window_id)
1580 .map(|window| window.focused_view_id)
1581 }
1582
1583 pub fn render_view(
1584 &self,
1585 window_id: usize,
1586 view_id: usize,
1587 titlebar_height: f32,
1588 ) -> Result<ElementBox> {
1589 self.views
1590 .get(&(window_id, view_id))
1591 .map(|v| v.render(window_id, view_id, titlebar_height, self))
1592 .ok_or(anyhow!("view not found"))
1593 }
1594
1595 pub fn render_views(
1596 &self,
1597 window_id: usize,
1598 titlebar_height: f32,
1599 ) -> HashMap<usize, ElementBox> {
1600 self.views
1601 .iter()
1602 .filter_map(|((win_id, view_id), view)| {
1603 if *win_id == window_id {
1604 Some((
1605 *view_id,
1606 view.render(*win_id, *view_id, titlebar_height, self),
1607 ))
1608 } else {
1609 None
1610 }
1611 })
1612 .collect::<HashMap<_, ElementBox>>()
1613 }
1614
1615 pub fn background(&self) -> &Arc<executor::Background> {
1616 &self.background
1617 }
1618
1619 pub fn font_cache(&self) -> &Arc<FontCache> {
1620 &self.font_cache
1621 }
1622
1623 pub fn platform(&self) -> &Arc<dyn Platform> {
1624 &self.platform
1625 }
1626
1627 pub fn value<Tag: 'static, T: 'static + Default>(&self, id: usize) -> ValueHandle<T> {
1628 let key = (TypeId::of::<Tag>(), id);
1629 self.values
1630 .write()
1631 .entry(key)
1632 .or_insert_with(|| Box::new(T::default()));
1633 ValueHandle::new(TypeId::of::<Tag>(), id, &self.ref_counts)
1634 }
1635}
1636
1637impl ReadModel for AppContext {
1638 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
1639 if let Some(model) = self.models.get(&handle.model_id) {
1640 model
1641 .as_any()
1642 .downcast_ref()
1643 .expect("downcast should be type safe")
1644 } else {
1645 panic!("circular model reference");
1646 }
1647 }
1648}
1649
1650impl UpgradeModelHandle for AppContext {
1651 fn upgrade_model_handle<T: Entity>(
1652 &self,
1653 handle: WeakModelHandle<T>,
1654 ) -> Option<ModelHandle<T>> {
1655 if self.models.contains_key(&handle.model_id) {
1656 Some(ModelHandle::new(handle.model_id, &self.ref_counts))
1657 } else {
1658 None
1659 }
1660 }
1661}
1662
1663impl ReadView for AppContext {
1664 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
1665 if let Some(view) = self.views.get(&(handle.window_id, handle.view_id)) {
1666 view.as_any()
1667 .downcast_ref()
1668 .expect("downcast should be type safe")
1669 } else {
1670 panic!("circular view reference");
1671 }
1672 }
1673}
1674
1675struct Window {
1676 root_view: AnyViewHandle,
1677 focused_view_id: usize,
1678 invalidation: Option<WindowInvalidation>,
1679}
1680
1681#[derive(Default, Clone)]
1682pub struct WindowInvalidation {
1683 pub updated: HashSet<usize>,
1684 pub removed: Vec<usize>,
1685}
1686
1687pub enum Effect {
1688 Event {
1689 entity_id: usize,
1690 payload: Box<dyn Any>,
1691 },
1692 ModelNotification {
1693 model_id: usize,
1694 },
1695 ViewNotification {
1696 window_id: usize,
1697 view_id: usize,
1698 },
1699 Focus {
1700 window_id: usize,
1701 view_id: usize,
1702 },
1703}
1704
1705impl Debug for Effect {
1706 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1707 match self {
1708 Effect::Event { entity_id, .. } => f
1709 .debug_struct("Effect::Event")
1710 .field("entity_id", entity_id)
1711 .finish(),
1712 Effect::ModelNotification { model_id } => f
1713 .debug_struct("Effect::ModelNotification")
1714 .field("model_id", model_id)
1715 .finish(),
1716 Effect::ViewNotification { window_id, view_id } => f
1717 .debug_struct("Effect::ViewNotification")
1718 .field("window_id", window_id)
1719 .field("view_id", view_id)
1720 .finish(),
1721 Effect::Focus { window_id, view_id } => f
1722 .debug_struct("Effect::Focus")
1723 .field("window_id", window_id)
1724 .field("view_id", view_id)
1725 .finish(),
1726 }
1727 }
1728}
1729
1730pub trait AnyModel {
1731 fn as_any(&self) -> &dyn Any;
1732 fn as_any_mut(&mut self) -> &mut dyn Any;
1733 fn release(&mut self, cx: &mut MutableAppContext);
1734}
1735
1736impl<T> AnyModel for T
1737where
1738 T: Entity,
1739{
1740 fn as_any(&self) -> &dyn Any {
1741 self
1742 }
1743
1744 fn as_any_mut(&mut self) -> &mut dyn Any {
1745 self
1746 }
1747
1748 fn release(&mut self, cx: &mut MutableAppContext) {
1749 self.release(cx);
1750 }
1751}
1752
1753pub trait AnyView {
1754 fn as_any(&self) -> &dyn Any;
1755 fn as_any_mut(&mut self) -> &mut dyn Any;
1756 fn release(&mut self, cx: &mut MutableAppContext);
1757 fn ui_name(&self) -> &'static str;
1758 fn render<'a>(
1759 &self,
1760 window_id: usize,
1761 view_id: usize,
1762 titlebar_height: f32,
1763 cx: &AppContext,
1764 ) -> ElementBox;
1765 fn on_focus(&mut self, cx: &mut MutableAppContext, window_id: usize, view_id: usize);
1766 fn on_blur(&mut self, cx: &mut MutableAppContext, window_id: usize, view_id: usize);
1767 fn keymap_context(&self, cx: &AppContext) -> keymap::Context;
1768}
1769
1770impl<T> AnyView for T
1771where
1772 T: View,
1773{
1774 fn as_any(&self) -> &dyn Any {
1775 self
1776 }
1777
1778 fn as_any_mut(&mut self) -> &mut dyn Any {
1779 self
1780 }
1781
1782 fn release(&mut self, cx: &mut MutableAppContext) {
1783 self.release(cx);
1784 }
1785
1786 fn ui_name(&self) -> &'static str {
1787 T::ui_name()
1788 }
1789
1790 fn render<'a>(
1791 &self,
1792 window_id: usize,
1793 view_id: usize,
1794 titlebar_height: f32,
1795 cx: &AppContext,
1796 ) -> ElementBox {
1797 View::render(
1798 self,
1799 &RenderContext {
1800 window_id,
1801 view_id,
1802 app: cx,
1803 view_type: PhantomData::<T>,
1804 titlebar_height,
1805 },
1806 )
1807 }
1808
1809 fn on_focus(&mut self, cx: &mut MutableAppContext, window_id: usize, view_id: usize) {
1810 let mut cx = ViewContext::new(cx, window_id, view_id);
1811 View::on_focus(self, &mut cx);
1812 }
1813
1814 fn on_blur(&mut self, cx: &mut MutableAppContext, window_id: usize, view_id: usize) {
1815 let mut cx = ViewContext::new(cx, window_id, view_id);
1816 View::on_blur(self, &mut cx);
1817 }
1818
1819 fn keymap_context(&self, cx: &AppContext) -> keymap::Context {
1820 View::keymap_context(self, cx)
1821 }
1822}
1823
1824pub struct ModelContext<'a, T: ?Sized> {
1825 app: &'a mut MutableAppContext,
1826 model_id: usize,
1827 model_type: PhantomData<T>,
1828 halt_stream: bool,
1829}
1830
1831impl<'a, T: Entity> ModelContext<'a, T> {
1832 fn new(app: &'a mut MutableAppContext, model_id: usize) -> Self {
1833 Self {
1834 app,
1835 model_id,
1836 model_type: PhantomData,
1837 halt_stream: false,
1838 }
1839 }
1840
1841 pub fn background(&self) -> &Arc<executor::Background> {
1842 &self.app.cx.background
1843 }
1844
1845 pub fn halt_stream(&mut self) {
1846 self.halt_stream = true;
1847 }
1848
1849 pub fn model_id(&self) -> usize {
1850 self.model_id
1851 }
1852
1853 pub fn add_model<S, F>(&mut self, build_model: F) -> ModelHandle<S>
1854 where
1855 S: Entity,
1856 F: FnOnce(&mut ModelContext<S>) -> S,
1857 {
1858 self.app.add_model(build_model)
1859 }
1860
1861 pub fn emit(&mut self, payload: T::Event) {
1862 self.app.pending_effects.push_back(Effect::Event {
1863 entity_id: self.model_id,
1864 payload: Box::new(payload),
1865 });
1866 }
1867
1868 pub fn notify(&mut self) {
1869 self.app
1870 .pending_effects
1871 .push_back(Effect::ModelNotification {
1872 model_id: self.model_id,
1873 });
1874 }
1875
1876 pub fn subscribe<S: Entity, F>(&mut self, handle: &ModelHandle<S>, mut callback: F)
1877 where
1878 S::Event: 'static,
1879 F: 'static + FnMut(&mut T, ModelHandle<S>, &S::Event, &mut ModelContext<T>),
1880 {
1881 let subscriber = self.handle().downgrade();
1882 self.app
1883 .subscribe_internal(handle, move |emitter, event, cx| {
1884 if let Some(subscriber) = subscriber.upgrade(cx) {
1885 subscriber.update(cx, |subscriber, cx| {
1886 callback(subscriber, emitter, event, cx);
1887 });
1888 true
1889 } else {
1890 false
1891 }
1892 });
1893 }
1894
1895 pub fn observe<S, F>(&mut self, handle: &ModelHandle<S>, mut callback: F)
1896 where
1897 S: Entity,
1898 F: 'static + FnMut(&mut T, ModelHandle<S>, &mut ModelContext<T>),
1899 {
1900 let observer = self.handle().downgrade();
1901 self.app.observe_internal(handle, move |observed, cx| {
1902 if let Some(observer) = observer.upgrade(cx) {
1903 observer.update(cx, |observer, cx| {
1904 callback(observer, observed, cx);
1905 });
1906 true
1907 } else {
1908 false
1909 }
1910 });
1911 }
1912
1913 pub fn handle(&self) -> ModelHandle<T> {
1914 ModelHandle::new(self.model_id, &self.app.cx.ref_counts)
1915 }
1916
1917 pub fn spawn<F, Fut, S>(&self, f: F) -> Task<S>
1918 where
1919 F: FnOnce(ModelHandle<T>, AsyncAppContext) -> Fut,
1920 Fut: 'static + Future<Output = S>,
1921 S: 'static,
1922 {
1923 let handle = self.handle();
1924 self.app.spawn(|cx| f(handle, cx))
1925 }
1926
1927 pub fn spawn_weak<F, Fut, S>(&self, f: F) -> Task<S>
1928 where
1929 F: FnOnce(WeakModelHandle<T>, AsyncAppContext) -> Fut,
1930 Fut: 'static + Future<Output = S>,
1931 S: 'static,
1932 {
1933 let handle = self.handle().downgrade();
1934 self.app.spawn(|cx| f(handle, cx))
1935 }
1936}
1937
1938impl<M> AsRef<AppContext> for ModelContext<'_, M> {
1939 fn as_ref(&self) -> &AppContext {
1940 &self.app.cx
1941 }
1942}
1943
1944impl<M> AsMut<MutableAppContext> for ModelContext<'_, M> {
1945 fn as_mut(&mut self) -> &mut MutableAppContext {
1946 self.app
1947 }
1948}
1949
1950impl<M> ReadModel for ModelContext<'_, M> {
1951 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
1952 self.app.read_model(handle)
1953 }
1954}
1955
1956impl<M> UpdateModel for ModelContext<'_, M> {
1957 fn update_model<T, F, S>(&mut self, handle: &ModelHandle<T>, update: F) -> S
1958 where
1959 T: Entity,
1960 F: FnOnce(&mut T, &mut ModelContext<T>) -> S,
1961 {
1962 self.app.update_model(handle, update)
1963 }
1964}
1965
1966impl<M> UpgradeModelHandle for ModelContext<'_, M> {
1967 fn upgrade_model_handle<T: Entity>(
1968 &self,
1969 handle: WeakModelHandle<T>,
1970 ) -> Option<ModelHandle<T>> {
1971 self.cx.upgrade_model_handle(handle)
1972 }
1973}
1974
1975impl<M> Deref for ModelContext<'_, M> {
1976 type Target = MutableAppContext;
1977
1978 fn deref(&self) -> &Self::Target {
1979 &self.app
1980 }
1981}
1982
1983impl<M> DerefMut for ModelContext<'_, M> {
1984 fn deref_mut(&mut self) -> &mut Self::Target {
1985 &mut self.app
1986 }
1987}
1988
1989pub struct ViewContext<'a, T: ?Sized> {
1990 app: &'a mut MutableAppContext,
1991 window_id: usize,
1992 view_id: usize,
1993 view_type: PhantomData<T>,
1994 halt_action_dispatch: bool,
1995}
1996
1997impl<'a, T: View> ViewContext<'a, T> {
1998 fn new(app: &'a mut MutableAppContext, window_id: usize, view_id: usize) -> Self {
1999 Self {
2000 app,
2001 window_id,
2002 view_id,
2003 view_type: PhantomData,
2004 halt_action_dispatch: true,
2005 }
2006 }
2007
2008 pub fn handle(&self) -> ViewHandle<T> {
2009 ViewHandle::new(self.window_id, self.view_id, &self.app.cx.ref_counts)
2010 }
2011
2012 pub fn window_id(&self) -> usize {
2013 self.window_id
2014 }
2015
2016 pub fn view_id(&self) -> usize {
2017 self.view_id
2018 }
2019
2020 pub fn foreground(&self) -> &Rc<executor::Foreground> {
2021 self.app.foreground()
2022 }
2023
2024 pub fn background_executor(&self) -> &Arc<executor::Background> {
2025 &self.app.cx.background
2026 }
2027
2028 pub fn platform(&self) -> Arc<dyn Platform> {
2029 self.app.platform()
2030 }
2031
2032 pub fn prompt<F>(&self, level: PromptLevel, msg: &str, answers: &[&str], done_fn: F)
2033 where
2034 F: 'static + FnOnce(usize, &mut MutableAppContext),
2035 {
2036 self.app
2037 .prompt(self.window_id, level, msg, answers, done_fn)
2038 }
2039
2040 pub fn prompt_for_paths<F>(&self, options: PathPromptOptions, done_fn: F)
2041 where
2042 F: 'static + FnOnce(Option<Vec<PathBuf>>, &mut MutableAppContext),
2043 {
2044 self.app.prompt_for_paths(options, done_fn)
2045 }
2046
2047 pub fn prompt_for_new_path<F>(&self, directory: &Path, done_fn: F)
2048 where
2049 F: 'static + FnOnce(Option<PathBuf>, &mut MutableAppContext),
2050 {
2051 self.app.prompt_for_new_path(directory, done_fn)
2052 }
2053
2054 pub fn debug_elements(&self) -> crate::json::Value {
2055 self.app.debug_elements(self.window_id).unwrap()
2056 }
2057
2058 pub fn focus<S>(&mut self, handle: S)
2059 where
2060 S: Into<AnyViewHandle>,
2061 {
2062 let handle = handle.into();
2063 self.app.pending_effects.push_back(Effect::Focus {
2064 window_id: handle.window_id,
2065 view_id: handle.view_id,
2066 });
2067 }
2068
2069 pub fn focus_self(&mut self) {
2070 self.app.pending_effects.push_back(Effect::Focus {
2071 window_id: self.window_id,
2072 view_id: self.view_id,
2073 });
2074 }
2075
2076 pub fn add_model<S, F>(&mut self, build_model: F) -> ModelHandle<S>
2077 where
2078 S: Entity,
2079 F: FnOnce(&mut ModelContext<S>) -> S,
2080 {
2081 self.app.add_model(build_model)
2082 }
2083
2084 pub fn add_view<S, F>(&mut self, build_view: F) -> ViewHandle<S>
2085 where
2086 S: View,
2087 F: FnOnce(&mut ViewContext<S>) -> S,
2088 {
2089 self.app.add_view(self.window_id, build_view)
2090 }
2091
2092 pub fn add_option_view<S, F>(&mut self, build_view: F) -> Option<ViewHandle<S>>
2093 where
2094 S: View,
2095 F: FnOnce(&mut ViewContext<S>) -> Option<S>,
2096 {
2097 self.app.add_option_view(self.window_id, build_view)
2098 }
2099
2100 pub fn subscribe_to_model<E, F>(&mut self, handle: &ModelHandle<E>, callback: F)
2101 where
2102 E: Entity,
2103 E::Event: 'static,
2104 F: 'static + FnMut(&mut T, ModelHandle<E>, &E::Event, &mut ViewContext<T>),
2105 {
2106 self.subscribe(handle, callback)
2107 }
2108
2109 pub fn subscribe_to_view<V, F>(&mut self, handle: &ViewHandle<V>, callback: F)
2110 where
2111 V: View,
2112 V::Event: 'static,
2113 F: 'static + FnMut(&mut T, ViewHandle<V>, &V::Event, &mut ViewContext<T>),
2114 {
2115 self.subscribe(handle, callback)
2116 }
2117
2118 pub fn observe_model<S, F>(&mut self, handle: &ModelHandle<S>, callback: F)
2119 where
2120 S: Entity,
2121 F: 'static + FnMut(&mut T, ModelHandle<S>, &mut ViewContext<T>),
2122 {
2123 self.observe(handle, callback)
2124 }
2125
2126 pub fn observe_view<S, F>(&mut self, handle: &ViewHandle<S>, callback: F)
2127 where
2128 S: View,
2129 F: 'static + FnMut(&mut T, ViewHandle<S>, &mut ViewContext<T>),
2130 {
2131 self.observe(handle, callback)
2132 }
2133
2134 pub fn subscribe<E, H, F>(&mut self, handle: &H, mut callback: F)
2135 where
2136 E: Entity,
2137 E::Event: 'static,
2138 H: Handle<E>,
2139 F: 'static + FnMut(&mut T, H, &E::Event, &mut ViewContext<T>),
2140 {
2141 let subscriber = self.handle().downgrade();
2142 self.app
2143 .subscribe_internal(handle, move |emitter, event, cx| {
2144 if let Some(subscriber) = subscriber.upgrade(cx) {
2145 subscriber.update(cx, |subscriber, cx| {
2146 callback(subscriber, emitter, event, cx);
2147 });
2148 true
2149 } else {
2150 false
2151 }
2152 });
2153 }
2154
2155 fn observe<E, F, H>(&mut self, handle: &H, mut callback: F)
2156 where
2157 E: Entity,
2158 H: Handle<E>,
2159 F: 'static + FnMut(&mut T, H, &mut ViewContext<T>),
2160 {
2161 let observer = self.handle().downgrade();
2162 self.app.observe_internal(handle, move |observed, cx| {
2163 if let Some(observer) = observer.upgrade(cx) {
2164 observer.update(cx, |observer, cx| {
2165 callback(observer, observed, cx);
2166 });
2167 true
2168 } else {
2169 false
2170 }
2171 });
2172 }
2173
2174 pub fn emit(&mut self, payload: T::Event) {
2175 self.app.pending_effects.push_back(Effect::Event {
2176 entity_id: self.view_id,
2177 payload: Box::new(payload),
2178 });
2179 }
2180
2181 pub fn notify(&mut self) {
2182 self.app.notify_view(self.window_id, self.view_id);
2183 }
2184
2185 pub fn notify_all(&mut self) {
2186 self.app.notify_all_views();
2187 }
2188
2189 pub fn propagate_action(&mut self) {
2190 self.halt_action_dispatch = false;
2191 }
2192
2193 pub fn spawn<F, Fut, S>(&self, f: F) -> Task<S>
2194 where
2195 F: FnOnce(ViewHandle<T>, AsyncAppContext) -> Fut,
2196 Fut: 'static + Future<Output = S>,
2197 S: 'static,
2198 {
2199 let handle = self.handle();
2200 self.app.spawn(|cx| f(handle, cx))
2201 }
2202}
2203
2204pub struct RenderContext<'a, T: View> {
2205 pub app: &'a AppContext,
2206 pub titlebar_height: f32,
2207 window_id: usize,
2208 view_id: usize,
2209 view_type: PhantomData<T>,
2210}
2211
2212impl<'a, T: View> RenderContext<'a, T> {
2213 pub fn handle(&self) -> WeakViewHandle<T> {
2214 WeakViewHandle::new(self.window_id, self.view_id)
2215 }
2216}
2217
2218impl AsRef<AppContext> for &AppContext {
2219 fn as_ref(&self) -> &AppContext {
2220 self
2221 }
2222}
2223
2224impl<V: View> Deref for RenderContext<'_, V> {
2225 type Target = AppContext;
2226
2227 fn deref(&self) -> &Self::Target {
2228 &self.app
2229 }
2230}
2231
2232impl<M> AsRef<AppContext> for ViewContext<'_, M> {
2233 fn as_ref(&self) -> &AppContext {
2234 &self.app.cx
2235 }
2236}
2237
2238impl<M> Deref for ViewContext<'_, M> {
2239 type Target = MutableAppContext;
2240
2241 fn deref(&self) -> &Self::Target {
2242 &self.app
2243 }
2244}
2245
2246impl<M> DerefMut for ViewContext<'_, M> {
2247 fn deref_mut(&mut self) -> &mut Self::Target {
2248 &mut self.app
2249 }
2250}
2251
2252impl<M> AsMut<MutableAppContext> for ViewContext<'_, M> {
2253 fn as_mut(&mut self) -> &mut MutableAppContext {
2254 self.app
2255 }
2256}
2257
2258impl<V> ReadModel for ViewContext<'_, V> {
2259 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
2260 self.app.read_model(handle)
2261 }
2262}
2263
2264impl<V> UpgradeModelHandle for ViewContext<'_, V> {
2265 fn upgrade_model_handle<T: Entity>(
2266 &self,
2267 handle: WeakModelHandle<T>,
2268 ) -> Option<ModelHandle<T>> {
2269 self.cx.upgrade_model_handle(handle)
2270 }
2271}
2272
2273impl<V: View> UpdateModel for ViewContext<'_, V> {
2274 fn update_model<T, F, S>(&mut self, handle: &ModelHandle<T>, update: F) -> S
2275 where
2276 T: Entity,
2277 F: FnOnce(&mut T, &mut ModelContext<T>) -> S,
2278 {
2279 self.app.update_model(handle, update)
2280 }
2281}
2282
2283impl<V: View> ReadView for ViewContext<'_, V> {
2284 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
2285 self.app.read_view(handle)
2286 }
2287}
2288
2289impl<V: View> UpdateView for ViewContext<'_, V> {
2290 fn update_view<T, F, S>(&mut self, handle: &ViewHandle<T>, update: F) -> S
2291 where
2292 T: View,
2293 F: FnOnce(&mut T, &mut ViewContext<T>) -> S,
2294 {
2295 self.app.update_view(handle, update)
2296 }
2297}
2298
2299pub trait Handle<T> {
2300 type Weak: 'static;
2301 fn id(&self) -> usize;
2302 fn location(&self) -> EntityLocation;
2303 fn downgrade(&self) -> Self::Weak;
2304 fn upgrade_from(weak: &Self::Weak, cx: &AppContext) -> Option<Self>
2305 where
2306 Self: Sized;
2307}
2308
2309#[derive(Clone, Copy, Debug, Eq, PartialEq, Hash)]
2310pub enum EntityLocation {
2311 Model(usize),
2312 View(usize, usize),
2313}
2314
2315pub struct ModelHandle<T> {
2316 model_id: usize,
2317 model_type: PhantomData<T>,
2318 ref_counts: Arc<Mutex<RefCounts>>,
2319}
2320
2321impl<T: Entity> ModelHandle<T> {
2322 fn new(model_id: usize, ref_counts: &Arc<Mutex<RefCounts>>) -> Self {
2323 ref_counts.lock().inc_model(model_id);
2324 Self {
2325 model_id,
2326 model_type: PhantomData,
2327 ref_counts: ref_counts.clone(),
2328 }
2329 }
2330
2331 pub fn downgrade(&self) -> WeakModelHandle<T> {
2332 WeakModelHandle::new(self.model_id)
2333 }
2334
2335 pub fn id(&self) -> usize {
2336 self.model_id
2337 }
2338
2339 pub fn read<'a, C: ReadModel>(&self, cx: &'a C) -> &'a T {
2340 cx.read_model(self)
2341 }
2342
2343 pub fn read_with<'a, C, F, S>(&self, cx: &C, read: F) -> S
2344 where
2345 C: ReadModelWith,
2346 F: FnOnce(&T, &AppContext) -> S,
2347 {
2348 cx.read_model_with(self, read)
2349 }
2350
2351 pub fn update<C, F, S>(&self, cx: &mut C, update: F) -> S
2352 where
2353 C: UpdateModel,
2354 F: FnOnce(&mut T, &mut ModelContext<T>) -> S,
2355 {
2356 cx.update_model(self, update)
2357 }
2358
2359 pub fn condition(
2360 &self,
2361 cx: &TestAppContext,
2362 mut predicate: impl FnMut(&T, &AppContext) -> bool,
2363 ) -> impl Future<Output = ()> {
2364 let (tx, mut rx) = mpsc::channel(1024);
2365
2366 let mut cx = cx.cx.borrow_mut();
2367 cx.observe(self, {
2368 let mut tx = tx.clone();
2369 move |_, _| {
2370 tx.blocking_send(()).ok();
2371 }
2372 });
2373 cx.subscribe(self, {
2374 let mut tx = tx.clone();
2375 move |_, _, _| {
2376 tx.blocking_send(()).ok();
2377 }
2378 });
2379
2380 let cx = cx.weak_self.as_ref().unwrap().upgrade().unwrap();
2381 let handle = self.downgrade();
2382 let duration = if std::env::var("CI").is_ok() {
2383 Duration::from_secs(5)
2384 } else {
2385 Duration::from_secs(1)
2386 };
2387
2388 async move {
2389 timeout(duration, async move {
2390 loop {
2391 {
2392 let cx = cx.borrow();
2393 let cx = cx.as_ref();
2394 if predicate(
2395 handle
2396 .upgrade(cx)
2397 .expect("model dropped with pending condition")
2398 .read(cx),
2399 cx,
2400 ) {
2401 break;
2402 }
2403 }
2404
2405 rx.recv()
2406 .await
2407 .expect("model dropped with pending condition");
2408 }
2409 })
2410 .await
2411 .expect("condition timed out");
2412 }
2413 }
2414}
2415
2416impl<T> Clone for ModelHandle<T> {
2417 fn clone(&self) -> Self {
2418 self.ref_counts.lock().inc_model(self.model_id);
2419 Self {
2420 model_id: self.model_id,
2421 model_type: PhantomData,
2422 ref_counts: self.ref_counts.clone(),
2423 }
2424 }
2425}
2426
2427impl<T> PartialEq for ModelHandle<T> {
2428 fn eq(&self, other: &Self) -> bool {
2429 self.model_id == other.model_id
2430 }
2431}
2432
2433impl<T> Eq for ModelHandle<T> {}
2434
2435impl<T> Hash for ModelHandle<T> {
2436 fn hash<H: Hasher>(&self, state: &mut H) {
2437 self.model_id.hash(state);
2438 }
2439}
2440
2441impl<T> std::borrow::Borrow<usize> for ModelHandle<T> {
2442 fn borrow(&self) -> &usize {
2443 &self.model_id
2444 }
2445}
2446
2447impl<T> Debug for ModelHandle<T> {
2448 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
2449 f.debug_tuple(&format!("ModelHandle<{}>", type_name::<T>()))
2450 .field(&self.model_id)
2451 .finish()
2452 }
2453}
2454
2455unsafe impl<T> Send for ModelHandle<T> {}
2456unsafe impl<T> Sync for ModelHandle<T> {}
2457
2458impl<T> Drop for ModelHandle<T> {
2459 fn drop(&mut self) {
2460 self.ref_counts.lock().dec_model(self.model_id);
2461 }
2462}
2463
2464impl<T: Entity> Handle<T> for ModelHandle<T> {
2465 type Weak = WeakModelHandle<T>;
2466
2467 fn id(&self) -> usize {
2468 self.model_id
2469 }
2470
2471 fn location(&self) -> EntityLocation {
2472 EntityLocation::Model(self.model_id)
2473 }
2474
2475 fn downgrade(&self) -> Self::Weak {
2476 self.downgrade()
2477 }
2478
2479 fn upgrade_from(weak: &Self::Weak, cx: &AppContext) -> Option<Self>
2480 where
2481 Self: Sized,
2482 {
2483 weak.upgrade(cx)
2484 }
2485}
2486
2487pub struct WeakModelHandle<T> {
2488 model_id: usize,
2489 model_type: PhantomData<T>,
2490}
2491
2492unsafe impl<T> Send for WeakModelHandle<T> {}
2493unsafe impl<T> Sync for WeakModelHandle<T> {}
2494
2495impl<T: Entity> WeakModelHandle<T> {
2496 fn new(model_id: usize) -> Self {
2497 Self {
2498 model_id,
2499 model_type: PhantomData,
2500 }
2501 }
2502
2503 pub fn upgrade(self, cx: &impl UpgradeModelHandle) -> Option<ModelHandle<T>> {
2504 cx.upgrade_model_handle(self)
2505 }
2506}
2507
2508impl<T> Hash for WeakModelHandle<T> {
2509 fn hash<H: Hasher>(&self, state: &mut H) {
2510 self.model_id.hash(state)
2511 }
2512}
2513
2514impl<T> PartialEq for WeakModelHandle<T> {
2515 fn eq(&self, other: &Self) -> bool {
2516 self.model_id == other.model_id
2517 }
2518}
2519
2520impl<T> Eq for WeakModelHandle<T> {}
2521
2522impl<T> Clone for WeakModelHandle<T> {
2523 fn clone(&self) -> Self {
2524 Self {
2525 model_id: self.model_id,
2526 model_type: PhantomData,
2527 }
2528 }
2529}
2530
2531impl<T> Copy for WeakModelHandle<T> {}
2532
2533pub struct ViewHandle<T> {
2534 window_id: usize,
2535 view_id: usize,
2536 view_type: PhantomData<T>,
2537 ref_counts: Arc<Mutex<RefCounts>>,
2538}
2539
2540impl<T: View> ViewHandle<T> {
2541 fn new(window_id: usize, view_id: usize, ref_counts: &Arc<Mutex<RefCounts>>) -> Self {
2542 ref_counts.lock().inc_view(window_id, view_id);
2543 Self {
2544 window_id,
2545 view_id,
2546 view_type: PhantomData,
2547 ref_counts: ref_counts.clone(),
2548 }
2549 }
2550
2551 pub fn downgrade(&self) -> WeakViewHandle<T> {
2552 WeakViewHandle::new(self.window_id, self.view_id)
2553 }
2554
2555 pub fn window_id(&self) -> usize {
2556 self.window_id
2557 }
2558
2559 pub fn id(&self) -> usize {
2560 self.view_id
2561 }
2562
2563 pub fn read<'a, C: ReadView>(&self, cx: &'a C) -> &'a T {
2564 cx.read_view(self)
2565 }
2566
2567 pub fn read_with<C, F, S>(&self, cx: &C, read: F) -> S
2568 where
2569 C: ReadViewWith,
2570 F: FnOnce(&T, &AppContext) -> S,
2571 {
2572 cx.read_view_with(self, read)
2573 }
2574
2575 pub fn update<C, F, S>(&self, cx: &mut C, update: F) -> S
2576 where
2577 C: UpdateView,
2578 F: FnOnce(&mut T, &mut ViewContext<T>) -> S,
2579 {
2580 cx.update_view(self, update)
2581 }
2582
2583 pub fn is_focused(&self, cx: &AppContext) -> bool {
2584 cx.focused_view_id(self.window_id)
2585 .map_or(false, |focused_id| focused_id == self.view_id)
2586 }
2587
2588 pub fn condition(
2589 &self,
2590 cx: &TestAppContext,
2591 mut predicate: impl FnMut(&T, &AppContext) -> bool,
2592 ) -> impl Future<Output = ()> {
2593 let (tx, mut rx) = mpsc::channel(1024);
2594
2595 let mut cx = cx.cx.borrow_mut();
2596 self.update(&mut *cx, |_, cx| {
2597 cx.observe_view(self, {
2598 let mut tx = tx.clone();
2599 move |_, _, _| {
2600 tx.blocking_send(()).ok();
2601 }
2602 });
2603
2604 cx.subscribe_to_view(self, {
2605 let mut tx = tx.clone();
2606 move |_, _, _, _| {
2607 tx.blocking_send(()).ok();
2608 }
2609 })
2610 });
2611
2612 let cx = cx.weak_self.as_ref().unwrap().upgrade().unwrap();
2613 let handle = self.downgrade();
2614 let duration = if std::env::var("CI").is_ok() {
2615 Duration::from_secs(2)
2616 } else {
2617 Duration::from_millis(500)
2618 };
2619
2620 async move {
2621 timeout(duration, async move {
2622 loop {
2623 {
2624 let cx = cx.borrow();
2625 let cx = cx.as_ref();
2626 if predicate(
2627 handle
2628 .upgrade(cx)
2629 .expect("view dropped with pending condition")
2630 .read(cx),
2631 cx,
2632 ) {
2633 break;
2634 }
2635 }
2636
2637 rx.recv()
2638 .await
2639 .expect("view dropped with pending condition");
2640 }
2641 })
2642 .await
2643 .expect("condition timed out");
2644 }
2645 }
2646}
2647
2648impl<T> Clone for ViewHandle<T> {
2649 fn clone(&self) -> Self {
2650 self.ref_counts
2651 .lock()
2652 .inc_view(self.window_id, self.view_id);
2653 Self {
2654 window_id: self.window_id,
2655 view_id: self.view_id,
2656 view_type: PhantomData,
2657 ref_counts: self.ref_counts.clone(),
2658 }
2659 }
2660}
2661
2662impl<T> PartialEq for ViewHandle<T> {
2663 fn eq(&self, other: &Self) -> bool {
2664 self.window_id == other.window_id && self.view_id == other.view_id
2665 }
2666}
2667
2668impl<T> Eq for ViewHandle<T> {}
2669
2670impl<T> Debug for ViewHandle<T> {
2671 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
2672 f.debug_struct(&format!("ViewHandle<{}>", type_name::<T>()))
2673 .field("window_id", &self.window_id)
2674 .field("view_id", &self.view_id)
2675 .finish()
2676 }
2677}
2678
2679impl<T> Drop for ViewHandle<T> {
2680 fn drop(&mut self) {
2681 self.ref_counts
2682 .lock()
2683 .dec_view(self.window_id, self.view_id);
2684 }
2685}
2686
2687impl<T: View> Handle<T> for ViewHandle<T> {
2688 type Weak = WeakViewHandle<T>;
2689
2690 fn id(&self) -> usize {
2691 self.view_id
2692 }
2693
2694 fn location(&self) -> EntityLocation {
2695 EntityLocation::View(self.window_id, self.view_id)
2696 }
2697
2698 fn downgrade(&self) -> Self::Weak {
2699 self.downgrade()
2700 }
2701
2702 fn upgrade_from(weak: &Self::Weak, cx: &AppContext) -> Option<Self>
2703 where
2704 Self: Sized,
2705 {
2706 weak.upgrade(cx)
2707 }
2708}
2709
2710pub struct AnyViewHandle {
2711 window_id: usize,
2712 view_id: usize,
2713 view_type: TypeId,
2714 ref_counts: Arc<Mutex<RefCounts>>,
2715}
2716
2717impl AnyViewHandle {
2718 pub fn id(&self) -> usize {
2719 self.view_id
2720 }
2721
2722 pub fn is<T: 'static>(&self) -> bool {
2723 TypeId::of::<T>() == self.view_type
2724 }
2725
2726 pub fn downcast<T: View>(self) -> Option<ViewHandle<T>> {
2727 if self.is::<T>() {
2728 let result = Some(ViewHandle {
2729 window_id: self.window_id,
2730 view_id: self.view_id,
2731 ref_counts: self.ref_counts.clone(),
2732 view_type: PhantomData,
2733 });
2734 unsafe {
2735 Arc::decrement_strong_count(&self.ref_counts);
2736 }
2737 std::mem::forget(self);
2738 result
2739 } else {
2740 None
2741 }
2742 }
2743}
2744
2745impl Clone for AnyViewHandle {
2746 fn clone(&self) -> Self {
2747 self.ref_counts
2748 .lock()
2749 .inc_view(self.window_id, self.view_id);
2750 Self {
2751 window_id: self.window_id,
2752 view_id: self.view_id,
2753 view_type: self.view_type,
2754 ref_counts: self.ref_counts.clone(),
2755 }
2756 }
2757}
2758
2759impl<T: View> From<&ViewHandle<T>> for AnyViewHandle {
2760 fn from(handle: &ViewHandle<T>) -> Self {
2761 handle
2762 .ref_counts
2763 .lock()
2764 .inc_view(handle.window_id, handle.view_id);
2765 AnyViewHandle {
2766 window_id: handle.window_id,
2767 view_id: handle.view_id,
2768 view_type: TypeId::of::<T>(),
2769 ref_counts: handle.ref_counts.clone(),
2770 }
2771 }
2772}
2773
2774impl<T: View> From<ViewHandle<T>> for AnyViewHandle {
2775 fn from(handle: ViewHandle<T>) -> Self {
2776 let any_handle = AnyViewHandle {
2777 window_id: handle.window_id,
2778 view_id: handle.view_id,
2779 view_type: TypeId::of::<T>(),
2780 ref_counts: handle.ref_counts.clone(),
2781 };
2782 unsafe {
2783 Arc::decrement_strong_count(&handle.ref_counts);
2784 }
2785 std::mem::forget(handle);
2786 any_handle
2787 }
2788}
2789
2790impl Drop for AnyViewHandle {
2791 fn drop(&mut self) {
2792 self.ref_counts
2793 .lock()
2794 .dec_view(self.window_id, self.view_id);
2795 }
2796}
2797
2798pub struct AnyModelHandle {
2799 model_id: usize,
2800 ref_counts: Arc<Mutex<RefCounts>>,
2801}
2802
2803impl<T: Entity> From<ModelHandle<T>> for AnyModelHandle {
2804 fn from(handle: ModelHandle<T>) -> Self {
2805 handle.ref_counts.lock().inc_model(handle.model_id);
2806 Self {
2807 model_id: handle.model_id,
2808 ref_counts: handle.ref_counts.clone(),
2809 }
2810 }
2811}
2812
2813impl Drop for AnyModelHandle {
2814 fn drop(&mut self) {
2815 self.ref_counts.lock().dec_model(self.model_id);
2816 }
2817}
2818pub struct WeakViewHandle<T> {
2819 window_id: usize,
2820 view_id: usize,
2821 view_type: PhantomData<T>,
2822}
2823
2824impl<T: View> WeakViewHandle<T> {
2825 fn new(window_id: usize, view_id: usize) -> Self {
2826 Self {
2827 window_id,
2828 view_id,
2829 view_type: PhantomData,
2830 }
2831 }
2832
2833 pub fn upgrade(&self, cx: &AppContext) -> Option<ViewHandle<T>> {
2834 if cx.ref_counts.lock().is_entity_alive(self.view_id) {
2835 Some(ViewHandle::new(
2836 self.window_id,
2837 self.view_id,
2838 &cx.ref_counts,
2839 ))
2840 } else {
2841 None
2842 }
2843 }
2844}
2845
2846impl<T> Clone for WeakViewHandle<T> {
2847 fn clone(&self) -> Self {
2848 Self {
2849 window_id: self.window_id,
2850 view_id: self.view_id,
2851 view_type: PhantomData,
2852 }
2853 }
2854}
2855
2856pub struct ValueHandle<T> {
2857 value_type: PhantomData<T>,
2858 tag_type_id: TypeId,
2859 id: usize,
2860 ref_counts: Weak<Mutex<RefCounts>>,
2861}
2862
2863impl<T: 'static> ValueHandle<T> {
2864 fn new(tag_type_id: TypeId, id: usize, ref_counts: &Arc<Mutex<RefCounts>>) -> Self {
2865 ref_counts.lock().inc_value(tag_type_id, id);
2866 Self {
2867 value_type: PhantomData,
2868 tag_type_id,
2869 id,
2870 ref_counts: Arc::downgrade(ref_counts),
2871 }
2872 }
2873
2874 pub fn read<R>(&self, cx: &AppContext, f: impl FnOnce(&T) -> R) -> R {
2875 f(cx.values
2876 .read()
2877 .get(&(self.tag_type_id, self.id))
2878 .unwrap()
2879 .downcast_ref()
2880 .unwrap())
2881 }
2882
2883 pub fn update<R>(
2884 &self,
2885 cx: &mut EventContext,
2886 f: impl FnOnce(&mut T, &mut EventContext) -> R,
2887 ) -> R {
2888 let mut value = cx
2889 .app
2890 .cx
2891 .values
2892 .write()
2893 .remove(&(self.tag_type_id, self.id))
2894 .unwrap();
2895 let result = f(value.downcast_mut().unwrap(), cx);
2896 cx.app
2897 .cx
2898 .values
2899 .write()
2900 .insert((self.tag_type_id, self.id), value);
2901 result
2902 }
2903}
2904
2905impl<T> Drop for ValueHandle<T> {
2906 fn drop(&mut self) {
2907 if let Some(ref_counts) = self.ref_counts.upgrade() {
2908 ref_counts.lock().dec_value(self.tag_type_id, self.id);
2909 }
2910 }
2911}
2912
2913#[derive(Default)]
2914struct RefCounts {
2915 entity_counts: HashMap<usize, usize>,
2916 value_counts: HashMap<(TypeId, usize), usize>,
2917 dropped_models: HashSet<usize>,
2918 dropped_views: HashSet<(usize, usize)>,
2919 dropped_values: HashSet<(TypeId, usize)>,
2920}
2921
2922impl RefCounts {
2923 fn inc_model(&mut self, model_id: usize) {
2924 match self.entity_counts.entry(model_id) {
2925 Entry::Occupied(mut entry) => *entry.get_mut() += 1,
2926 Entry::Vacant(entry) => {
2927 entry.insert(1);
2928 self.dropped_models.remove(&model_id);
2929 }
2930 }
2931 }
2932
2933 fn inc_view(&mut self, window_id: usize, view_id: usize) {
2934 match self.entity_counts.entry(view_id) {
2935 Entry::Occupied(mut entry) => *entry.get_mut() += 1,
2936 Entry::Vacant(entry) => {
2937 entry.insert(1);
2938 self.dropped_views.remove(&(window_id, view_id));
2939 }
2940 }
2941 }
2942
2943 fn inc_value(&mut self, tag_type_id: TypeId, id: usize) {
2944 *self.value_counts.entry((tag_type_id, id)).or_insert(0) += 1;
2945 }
2946
2947 fn dec_model(&mut self, model_id: usize) {
2948 let count = self.entity_counts.get_mut(&model_id).unwrap();
2949 *count -= 1;
2950 if *count == 0 {
2951 self.entity_counts.remove(&model_id);
2952 self.dropped_models.insert(model_id);
2953 }
2954 }
2955
2956 fn dec_view(&mut self, window_id: usize, view_id: usize) {
2957 let count = self.entity_counts.get_mut(&view_id).unwrap();
2958 *count -= 1;
2959 if *count == 0 {
2960 self.entity_counts.remove(&view_id);
2961 self.dropped_views.insert((window_id, view_id));
2962 }
2963 }
2964
2965 fn dec_value(&mut self, tag_type_id: TypeId, id: usize) {
2966 let key = (tag_type_id, id);
2967 let count = self.value_counts.get_mut(&key).unwrap();
2968 *count -= 1;
2969 if *count == 0 {
2970 self.value_counts.remove(&key);
2971 self.dropped_values.insert(key);
2972 }
2973 }
2974
2975 fn is_entity_alive(&self, entity_id: usize) -> bool {
2976 self.entity_counts.contains_key(&entity_id)
2977 }
2978
2979 fn take_dropped(
2980 &mut self,
2981 ) -> (
2982 HashSet<usize>,
2983 HashSet<(usize, usize)>,
2984 HashSet<(TypeId, usize)>,
2985 ) {
2986 let mut dropped_models = HashSet::new();
2987 let mut dropped_views = HashSet::new();
2988 let mut dropped_values = HashSet::new();
2989 std::mem::swap(&mut self.dropped_models, &mut dropped_models);
2990 std::mem::swap(&mut self.dropped_views, &mut dropped_views);
2991 std::mem::swap(&mut self.dropped_values, &mut dropped_values);
2992 (dropped_models, dropped_views, dropped_values)
2993 }
2994}
2995
2996#[cfg(test)]
2997mod tests {
2998 use super::*;
2999 use crate::elements::*;
3000 use smol::future::poll_once;
3001 use std::sync::atomic::{AtomicUsize, Ordering::SeqCst};
3002
3003 #[crate::test(self)]
3004 fn test_model_handles(cx: &mut MutableAppContext) {
3005 struct Model {
3006 other: Option<ModelHandle<Model>>,
3007 events: Vec<String>,
3008 }
3009
3010 impl Entity for Model {
3011 type Event = usize;
3012 }
3013
3014 impl Model {
3015 fn new(other: Option<ModelHandle<Self>>, cx: &mut ModelContext<Self>) -> Self {
3016 if let Some(other) = other.as_ref() {
3017 cx.observe(other, |me, _, _| {
3018 me.events.push("notified".into());
3019 });
3020 cx.subscribe(other, |me, _, event, _| {
3021 me.events.push(format!("observed event {}", event));
3022 });
3023 }
3024
3025 Self {
3026 other,
3027 events: Vec::new(),
3028 }
3029 }
3030 }
3031
3032 let handle_1 = cx.add_model(|cx| Model::new(None, cx));
3033 let handle_2 = cx.add_model(|cx| Model::new(Some(handle_1.clone()), cx));
3034 assert_eq!(cx.cx.models.len(), 2);
3035
3036 handle_1.update(cx, |model, cx| {
3037 model.events.push("updated".into());
3038 cx.emit(1);
3039 cx.notify();
3040 cx.emit(2);
3041 });
3042 assert_eq!(handle_1.read(cx).events, vec!["updated".to_string()]);
3043 assert_eq!(
3044 handle_2.read(cx).events,
3045 vec![
3046 "observed event 1".to_string(),
3047 "notified".to_string(),
3048 "observed event 2".to_string(),
3049 ]
3050 );
3051
3052 handle_2.update(cx, |model, _| {
3053 drop(handle_1);
3054 model.other.take();
3055 });
3056
3057 assert_eq!(cx.cx.models.len(), 1);
3058 assert!(cx.subscriptions.is_empty());
3059 assert!(cx.observations.is_empty());
3060 }
3061
3062 #[crate::test(self)]
3063 fn test_subscribe_and_emit_from_model(cx: &mut MutableAppContext) {
3064 #[derive(Default)]
3065 struct Model {
3066 events: Vec<usize>,
3067 }
3068
3069 impl Entity for Model {
3070 type Event = usize;
3071 }
3072
3073 let handle_1 = cx.add_model(|_| Model::default());
3074 let handle_2 = cx.add_model(|_| Model::default());
3075 let handle_2b = handle_2.clone();
3076
3077 handle_1.update(cx, |_, c| {
3078 c.subscribe(&handle_2, move |model: &mut Model, _, event, c| {
3079 model.events.push(*event);
3080
3081 c.subscribe(&handle_2b, |model, _, event, _| {
3082 model.events.push(*event * 2);
3083 });
3084 });
3085 });
3086
3087 handle_2.update(cx, |_, c| c.emit(7));
3088 assert_eq!(handle_1.read(cx).events, vec![7]);
3089
3090 handle_2.update(cx, |_, c| c.emit(5));
3091 assert_eq!(handle_1.read(cx).events, vec![7, 10, 5]);
3092 }
3093
3094 #[crate::test(self)]
3095 fn test_observe_and_notify_from_model(cx: &mut MutableAppContext) {
3096 #[derive(Default)]
3097 struct Model {
3098 count: usize,
3099 events: Vec<usize>,
3100 }
3101
3102 impl Entity for Model {
3103 type Event = ();
3104 }
3105
3106 let handle_1 = cx.add_model(|_| Model::default());
3107 let handle_2 = cx.add_model(|_| Model::default());
3108 let handle_2b = handle_2.clone();
3109
3110 handle_1.update(cx, |_, c| {
3111 c.observe(&handle_2, move |model, observed, c| {
3112 model.events.push(observed.read(c).count);
3113 c.observe(&handle_2b, |model, observed, c| {
3114 model.events.push(observed.read(c).count * 2);
3115 });
3116 });
3117 });
3118
3119 handle_2.update(cx, |model, c| {
3120 model.count = 7;
3121 c.notify()
3122 });
3123 assert_eq!(handle_1.read(cx).events, vec![7]);
3124
3125 handle_2.update(cx, |model, c| {
3126 model.count = 5;
3127 c.notify()
3128 });
3129 assert_eq!(handle_1.read(cx).events, vec![7, 10, 5])
3130 }
3131
3132 #[crate::test(self)]
3133 fn test_view_handles(cx: &mut MutableAppContext) {
3134 struct View {
3135 other: Option<ViewHandle<View>>,
3136 events: Vec<String>,
3137 }
3138
3139 impl Entity for View {
3140 type Event = usize;
3141 }
3142
3143 impl super::View for View {
3144 fn render<'a>(&self, _: &RenderContext<Self>) -> ElementBox {
3145 Empty::new().boxed()
3146 }
3147
3148 fn ui_name() -> &'static str {
3149 "View"
3150 }
3151 }
3152
3153 impl View {
3154 fn new(other: Option<ViewHandle<View>>, cx: &mut ViewContext<Self>) -> Self {
3155 if let Some(other) = other.as_ref() {
3156 cx.subscribe_to_view(other, |me, _, event, _| {
3157 me.events.push(format!("observed event {}", event));
3158 });
3159 }
3160 Self {
3161 other,
3162 events: Vec::new(),
3163 }
3164 }
3165 }
3166
3167 let (window_id, _) = cx.add_window(Default::default(), |cx| View::new(None, cx));
3168 let handle_1 = cx.add_view(window_id, |cx| View::new(None, cx));
3169 let handle_2 = cx.add_view(window_id, |cx| View::new(Some(handle_1.clone()), cx));
3170 assert_eq!(cx.cx.views.len(), 3);
3171
3172 handle_1.update(cx, |view, cx| {
3173 view.events.push("updated".into());
3174 cx.emit(1);
3175 cx.emit(2);
3176 });
3177 assert_eq!(handle_1.read(cx).events, vec!["updated".to_string()]);
3178 assert_eq!(
3179 handle_2.read(cx).events,
3180 vec![
3181 "observed event 1".to_string(),
3182 "observed event 2".to_string(),
3183 ]
3184 );
3185
3186 handle_2.update(cx, |view, _| {
3187 drop(handle_1);
3188 view.other.take();
3189 });
3190
3191 assert_eq!(cx.cx.views.len(), 2);
3192 assert!(cx.subscriptions.is_empty());
3193 assert!(cx.observations.is_empty());
3194 }
3195
3196 #[crate::test(self)]
3197 fn test_add_window(cx: &mut MutableAppContext) {
3198 struct View {
3199 mouse_down_count: Arc<AtomicUsize>,
3200 }
3201
3202 impl Entity for View {
3203 type Event = ();
3204 }
3205
3206 impl super::View for View {
3207 fn render<'a>(&self, _: &RenderContext<Self>) -> ElementBox {
3208 let mouse_down_count = self.mouse_down_count.clone();
3209 EventHandler::new(Empty::new().boxed())
3210 .on_mouse_down(move |_| {
3211 mouse_down_count.fetch_add(1, SeqCst);
3212 true
3213 })
3214 .boxed()
3215 }
3216
3217 fn ui_name() -> &'static str {
3218 "View"
3219 }
3220 }
3221
3222 let mouse_down_count = Arc::new(AtomicUsize::new(0));
3223 let (window_id, _) = cx.add_window(Default::default(), |_| View {
3224 mouse_down_count: mouse_down_count.clone(),
3225 });
3226 let presenter = cx.presenters_and_platform_windows[&window_id].0.clone();
3227 // Ensure window's root element is in a valid lifecycle state.
3228 presenter.borrow_mut().dispatch_event(
3229 Event::LeftMouseDown {
3230 position: Default::default(),
3231 cmd: false,
3232 },
3233 cx,
3234 );
3235 assert_eq!(mouse_down_count.load(SeqCst), 1);
3236 }
3237
3238 #[crate::test(self)]
3239 fn test_entity_release_hooks(cx: &mut MutableAppContext) {
3240 struct Model {
3241 released: Arc<Mutex<bool>>,
3242 }
3243
3244 struct View {
3245 released: Arc<Mutex<bool>>,
3246 }
3247
3248 impl Entity for Model {
3249 type Event = ();
3250
3251 fn release(&mut self, _: &mut MutableAppContext) {
3252 *self.released.lock() = true;
3253 }
3254 }
3255
3256 impl Entity for View {
3257 type Event = ();
3258
3259 fn release(&mut self, _: &mut MutableAppContext) {
3260 *self.released.lock() = true;
3261 }
3262 }
3263
3264 impl super::View for View {
3265 fn ui_name() -> &'static str {
3266 "View"
3267 }
3268
3269 fn render<'a>(&self, _: &RenderContext<Self>) -> ElementBox {
3270 Empty::new().boxed()
3271 }
3272 }
3273
3274 let model_released = Arc::new(Mutex::new(false));
3275 let view_released = Arc::new(Mutex::new(false));
3276
3277 let model = cx.add_model(|_| Model {
3278 released: model_released.clone(),
3279 });
3280
3281 let (window_id, _) = cx.add_window(Default::default(), |_| View {
3282 released: view_released.clone(),
3283 });
3284
3285 assert!(!*model_released.lock());
3286 assert!(!*view_released.lock());
3287
3288 cx.update(move || {
3289 drop(model);
3290 });
3291 assert!(*model_released.lock());
3292
3293 drop(cx.remove_window(window_id));
3294 assert!(*view_released.lock());
3295 }
3296
3297 #[crate::test(self)]
3298 fn test_subscribe_and_emit_from_view(cx: &mut MutableAppContext) {
3299 #[derive(Default)]
3300 struct View {
3301 events: Vec<usize>,
3302 }
3303
3304 impl Entity for View {
3305 type Event = usize;
3306 }
3307
3308 impl super::View for View {
3309 fn render<'a>(&self, _: &RenderContext<Self>) -> ElementBox {
3310 Empty::new().boxed()
3311 }
3312
3313 fn ui_name() -> &'static str {
3314 "View"
3315 }
3316 }
3317
3318 struct Model;
3319
3320 impl Entity for Model {
3321 type Event = usize;
3322 }
3323
3324 let (window_id, handle_1) = cx.add_window(Default::default(), |_| View::default());
3325 let handle_2 = cx.add_view(window_id, |_| View::default());
3326 let handle_2b = handle_2.clone();
3327 let handle_3 = cx.add_model(|_| Model);
3328
3329 handle_1.update(cx, |_, c| {
3330 c.subscribe_to_view(&handle_2, move |me, _, event, c| {
3331 me.events.push(*event);
3332
3333 c.subscribe_to_view(&handle_2b, |me, _, event, _| {
3334 me.events.push(*event * 2);
3335 });
3336 });
3337
3338 c.subscribe_to_model(&handle_3, |me, _, event, _| {
3339 me.events.push(*event);
3340 })
3341 });
3342
3343 handle_2.update(cx, |_, c| c.emit(7));
3344 assert_eq!(handle_1.read(cx).events, vec![7]);
3345
3346 handle_2.update(cx, |_, c| c.emit(5));
3347 assert_eq!(handle_1.read(cx).events, vec![7, 10, 5]);
3348
3349 handle_3.update(cx, |_, c| c.emit(9));
3350 assert_eq!(handle_1.read(cx).events, vec![7, 10, 5, 9]);
3351 }
3352
3353 #[crate::test(self)]
3354 fn test_dropping_subscribers(cx: &mut MutableAppContext) {
3355 struct View;
3356
3357 impl Entity for View {
3358 type Event = ();
3359 }
3360
3361 impl super::View for View {
3362 fn render<'a>(&self, _: &RenderContext<Self>) -> ElementBox {
3363 Empty::new().boxed()
3364 }
3365
3366 fn ui_name() -> &'static str {
3367 "View"
3368 }
3369 }
3370
3371 struct Model;
3372
3373 impl Entity for Model {
3374 type Event = ();
3375 }
3376
3377 let (window_id, _) = cx.add_window(Default::default(), |_| View);
3378 let observing_view = cx.add_view(window_id, |_| View);
3379 let emitting_view = cx.add_view(window_id, |_| View);
3380 let observing_model = cx.add_model(|_| Model);
3381 let observed_model = cx.add_model(|_| Model);
3382
3383 observing_view.update(cx, |_, cx| {
3384 cx.subscribe_to_view(&emitting_view, |_, _, _, _| {});
3385 cx.subscribe_to_model(&observed_model, |_, _, _, _| {});
3386 });
3387 observing_model.update(cx, |_, cx| {
3388 cx.subscribe(&observed_model, |_, _, _, _| {});
3389 });
3390
3391 cx.update(|| {
3392 drop(observing_view);
3393 drop(observing_model);
3394 });
3395
3396 emitting_view.update(cx, |_, cx| cx.emit(()));
3397 observed_model.update(cx, |_, cx| cx.emit(()));
3398 }
3399
3400 #[crate::test(self)]
3401 fn test_observe_and_notify_from_view(cx: &mut MutableAppContext) {
3402 #[derive(Default)]
3403 struct View {
3404 events: Vec<usize>,
3405 }
3406
3407 impl Entity for View {
3408 type Event = usize;
3409 }
3410
3411 impl super::View for View {
3412 fn render<'a>(&self, _: &RenderContext<Self>) -> ElementBox {
3413 Empty::new().boxed()
3414 }
3415
3416 fn ui_name() -> &'static str {
3417 "View"
3418 }
3419 }
3420
3421 #[derive(Default)]
3422 struct Model {
3423 count: usize,
3424 }
3425
3426 impl Entity for Model {
3427 type Event = ();
3428 }
3429
3430 let (_, view) = cx.add_window(Default::default(), |_| View::default());
3431 let model = cx.add_model(|_| Model::default());
3432
3433 view.update(cx, |_, c| {
3434 c.observe_model(&model, |me, observed, c| {
3435 me.events.push(observed.read(c).count)
3436 });
3437 });
3438
3439 model.update(cx, |model, c| {
3440 model.count = 11;
3441 c.notify();
3442 });
3443 assert_eq!(view.read(cx).events, vec![11]);
3444 }
3445
3446 #[crate::test(self)]
3447 fn test_dropping_observers(cx: &mut MutableAppContext) {
3448 struct View;
3449
3450 impl Entity for View {
3451 type Event = ();
3452 }
3453
3454 impl super::View for View {
3455 fn render<'a>(&self, _: &RenderContext<Self>) -> ElementBox {
3456 Empty::new().boxed()
3457 }
3458
3459 fn ui_name() -> &'static str {
3460 "View"
3461 }
3462 }
3463
3464 struct Model;
3465
3466 impl Entity for Model {
3467 type Event = ();
3468 }
3469
3470 let (window_id, _) = cx.add_window(Default::default(), |_| View);
3471 let observing_view = cx.add_view(window_id, |_| View);
3472 let observing_model = cx.add_model(|_| Model);
3473 let observed_model = cx.add_model(|_| Model);
3474
3475 observing_view.update(cx, |_, cx| {
3476 cx.observe_model(&observed_model, |_, _, _| {});
3477 });
3478 observing_model.update(cx, |_, cx| {
3479 cx.observe(&observed_model, |_, _, _| {});
3480 });
3481
3482 cx.update(|| {
3483 drop(observing_view);
3484 drop(observing_model);
3485 });
3486
3487 observed_model.update(cx, |_, cx| cx.notify());
3488 }
3489
3490 #[crate::test(self)]
3491 fn test_focus(cx: &mut MutableAppContext) {
3492 struct View {
3493 name: String,
3494 events: Arc<Mutex<Vec<String>>>,
3495 }
3496
3497 impl Entity for View {
3498 type Event = ();
3499 }
3500
3501 impl super::View for View {
3502 fn render<'a>(&self, _: &RenderContext<Self>) -> ElementBox {
3503 Empty::new().boxed()
3504 }
3505
3506 fn ui_name() -> &'static str {
3507 "View"
3508 }
3509
3510 fn on_focus(&mut self, _: &mut ViewContext<Self>) {
3511 self.events.lock().push(format!("{} focused", &self.name));
3512 }
3513
3514 fn on_blur(&mut self, _: &mut ViewContext<Self>) {
3515 self.events.lock().push(format!("{} blurred", &self.name));
3516 }
3517 }
3518
3519 let events: Arc<Mutex<Vec<String>>> = Default::default();
3520 let (window_id, view_1) = cx.add_window(Default::default(), |_| View {
3521 events: events.clone(),
3522 name: "view 1".to_string(),
3523 });
3524 let view_2 = cx.add_view(window_id, |_| View {
3525 events: events.clone(),
3526 name: "view 2".to_string(),
3527 });
3528
3529 view_1.update(cx, |_, cx| cx.focus(&view_2));
3530 view_1.update(cx, |_, cx| cx.focus(&view_1));
3531 view_1.update(cx, |_, cx| cx.focus(&view_2));
3532 view_1.update(cx, |_, _| drop(view_2));
3533
3534 assert_eq!(
3535 *events.lock(),
3536 [
3537 "view 1 focused".to_string(),
3538 "view 1 blurred".to_string(),
3539 "view 2 focused".to_string(),
3540 "view 2 blurred".to_string(),
3541 "view 1 focused".to_string(),
3542 "view 1 blurred".to_string(),
3543 "view 2 focused".to_string(),
3544 "view 1 focused".to_string(),
3545 ],
3546 );
3547 }
3548
3549 #[crate::test(self)]
3550 fn test_dispatch_action(cx: &mut MutableAppContext) {
3551 struct ViewA {
3552 id: usize,
3553 }
3554
3555 impl Entity for ViewA {
3556 type Event = ();
3557 }
3558
3559 impl View for ViewA {
3560 fn render<'a>(&self, _: &RenderContext<Self>) -> ElementBox {
3561 Empty::new().boxed()
3562 }
3563
3564 fn ui_name() -> &'static str {
3565 "View"
3566 }
3567 }
3568
3569 struct ViewB {
3570 id: usize,
3571 }
3572
3573 impl Entity for ViewB {
3574 type Event = ();
3575 }
3576
3577 impl View for ViewB {
3578 fn render<'a>(&self, _: &RenderContext<Self>) -> ElementBox {
3579 Empty::new().boxed()
3580 }
3581
3582 fn ui_name() -> &'static str {
3583 "View"
3584 }
3585 }
3586
3587 action!(Action, &'static str);
3588
3589 let actions = Rc::new(RefCell::new(Vec::new()));
3590
3591 let actions_clone = actions.clone();
3592 cx.add_global_action(move |_: &Action, _: &mut MutableAppContext| {
3593 actions_clone.borrow_mut().push("global a".to_string());
3594 });
3595
3596 let actions_clone = actions.clone();
3597 cx.add_global_action(move |_: &Action, _: &mut MutableAppContext| {
3598 actions_clone.borrow_mut().push("global b".to_string());
3599 });
3600
3601 let actions_clone = actions.clone();
3602 cx.add_action(move |view: &mut ViewA, action: &Action, cx| {
3603 assert_eq!(action.0, "bar");
3604 cx.propagate_action();
3605 actions_clone.borrow_mut().push(format!("{} a", view.id));
3606 });
3607
3608 let actions_clone = actions.clone();
3609 cx.add_action(move |view: &mut ViewA, _: &Action, cx| {
3610 if view.id != 1 {
3611 cx.propagate_action();
3612 }
3613 actions_clone.borrow_mut().push(format!("{} b", view.id));
3614 });
3615
3616 let actions_clone = actions.clone();
3617 cx.add_action(move |view: &mut ViewB, _: &Action, cx| {
3618 cx.propagate_action();
3619 actions_clone.borrow_mut().push(format!("{} c", view.id));
3620 });
3621
3622 let actions_clone = actions.clone();
3623 cx.add_action(move |view: &mut ViewB, _: &Action, cx| {
3624 cx.propagate_action();
3625 actions_clone.borrow_mut().push(format!("{} d", view.id));
3626 });
3627
3628 let (window_id, view_1) = cx.add_window(Default::default(), |_| ViewA { id: 1 });
3629 let view_2 = cx.add_view(window_id, |_| ViewB { id: 2 });
3630 let view_3 = cx.add_view(window_id, |_| ViewA { id: 3 });
3631 let view_4 = cx.add_view(window_id, |_| ViewB { id: 4 });
3632
3633 cx.dispatch_action(
3634 window_id,
3635 vec![view_1.id(), view_2.id(), view_3.id(), view_4.id()],
3636 &Action("bar"),
3637 );
3638
3639 assert_eq!(
3640 *actions.borrow(),
3641 vec!["4 d", "4 c", "3 b", "3 a", "2 d", "2 c", "1 b"]
3642 );
3643
3644 // Remove view_1, which doesn't propagate the action
3645 actions.borrow_mut().clear();
3646 cx.dispatch_action(
3647 window_id,
3648 vec![view_2.id(), view_3.id(), view_4.id()],
3649 &Action("bar"),
3650 );
3651
3652 assert_eq!(
3653 *actions.borrow(),
3654 vec!["4 d", "4 c", "3 b", "3 a", "2 d", "2 c", "global b", "global a"]
3655 );
3656 }
3657
3658 #[crate::test(self)]
3659 fn test_dispatch_keystroke(cx: &mut MutableAppContext) {
3660 use std::cell::Cell;
3661
3662 action!(Action, &'static str);
3663
3664 struct View {
3665 id: usize,
3666 keymap_context: keymap::Context,
3667 }
3668
3669 impl Entity for View {
3670 type Event = ();
3671 }
3672
3673 impl super::View for View {
3674 fn render<'a>(&self, _: &RenderContext<Self>) -> ElementBox {
3675 Empty::new().boxed()
3676 }
3677
3678 fn ui_name() -> &'static str {
3679 "View"
3680 }
3681
3682 fn keymap_context(&self, _: &AppContext) -> keymap::Context {
3683 self.keymap_context.clone()
3684 }
3685 }
3686
3687 impl View {
3688 fn new(id: usize) -> Self {
3689 View {
3690 id,
3691 keymap_context: keymap::Context::default(),
3692 }
3693 }
3694 }
3695
3696 let mut view_1 = View::new(1);
3697 let mut view_2 = View::new(2);
3698 let mut view_3 = View::new(3);
3699 view_1.keymap_context.set.insert("a".into());
3700 view_2.keymap_context.set.insert("b".into());
3701 view_3.keymap_context.set.insert("c".into());
3702
3703 let (window_id, view_1) = cx.add_window(Default::default(), |_| view_1);
3704 let view_2 = cx.add_view(window_id, |_| view_2);
3705 let view_3 = cx.add_view(window_id, |_| view_3);
3706
3707 // This keymap's only binding dispatches an action on view 2 because that view will have
3708 // "a" and "b" in its context, but not "c".
3709 cx.add_bindings(vec![keymap::Binding::new(
3710 "a",
3711 Action("a"),
3712 Some("a && b && !c"),
3713 )]);
3714
3715 let handled_action = Rc::new(Cell::new(false));
3716 let handled_action_clone = handled_action.clone();
3717 cx.add_action(move |view: &mut View, action: &Action, _| {
3718 handled_action_clone.set(true);
3719 assert_eq!(view.id, 2);
3720 assert_eq!(action.0, "a");
3721 });
3722
3723 cx.dispatch_keystroke(
3724 window_id,
3725 vec![view_1.id(), view_2.id(), view_3.id()],
3726 &Keystroke::parse("a").unwrap(),
3727 )
3728 .unwrap();
3729
3730 assert!(handled_action.get());
3731 }
3732
3733 #[crate::test(self)]
3734 async fn test_model_condition(mut cx: TestAppContext) {
3735 struct Counter(usize);
3736
3737 impl super::Entity for Counter {
3738 type Event = ();
3739 }
3740
3741 impl Counter {
3742 fn inc(&mut self, cx: &mut ModelContext<Self>) {
3743 self.0 += 1;
3744 cx.notify();
3745 }
3746 }
3747
3748 let model = cx.add_model(|_| Counter(0));
3749
3750 let condition1 = model.condition(&cx, |model, _| model.0 == 2);
3751 let condition2 = model.condition(&cx, |model, _| model.0 == 3);
3752 smol::pin!(condition1, condition2);
3753
3754 model.update(&mut cx, |model, cx| model.inc(cx));
3755 assert_eq!(poll_once(&mut condition1).await, None);
3756 assert_eq!(poll_once(&mut condition2).await, None);
3757
3758 model.update(&mut cx, |model, cx| model.inc(cx));
3759 assert_eq!(poll_once(&mut condition1).await, Some(()));
3760 assert_eq!(poll_once(&mut condition2).await, None);
3761
3762 model.update(&mut cx, |model, cx| model.inc(cx));
3763 assert_eq!(poll_once(&mut condition2).await, Some(()));
3764
3765 model.update(&mut cx, |_, cx| cx.notify());
3766 }
3767
3768 #[crate::test(self)]
3769 #[should_panic]
3770 async fn test_model_condition_timeout(mut cx: TestAppContext) {
3771 struct Model;
3772
3773 impl super::Entity for Model {
3774 type Event = ();
3775 }
3776
3777 let model = cx.add_model(|_| Model);
3778 model.condition(&cx, |_, _| false).await;
3779 }
3780
3781 #[crate::test(self)]
3782 #[should_panic(expected = "model dropped with pending condition")]
3783 async fn test_model_condition_panic_on_drop(mut cx: TestAppContext) {
3784 struct Model;
3785
3786 impl super::Entity for Model {
3787 type Event = ();
3788 }
3789
3790 let model = cx.add_model(|_| Model);
3791 let condition = model.condition(&cx, |_, _| false);
3792 cx.update(|_| drop(model));
3793 condition.await;
3794 }
3795
3796 #[crate::test(self)]
3797 async fn test_view_condition(mut cx: TestAppContext) {
3798 struct Counter(usize);
3799
3800 impl super::Entity for Counter {
3801 type Event = ();
3802 }
3803
3804 impl super::View for Counter {
3805 fn ui_name() -> &'static str {
3806 "test view"
3807 }
3808
3809 fn render(&self, _: &RenderContext<Self>) -> ElementBox {
3810 Empty::new().boxed()
3811 }
3812 }
3813
3814 impl Counter {
3815 fn inc(&mut self, cx: &mut ViewContext<Self>) {
3816 self.0 += 1;
3817 cx.notify();
3818 }
3819 }
3820
3821 let (_, view) = cx.add_window(|_| Counter(0));
3822
3823 let condition1 = view.condition(&cx, |view, _| view.0 == 2);
3824 let condition2 = view.condition(&cx, |view, _| view.0 == 3);
3825 smol::pin!(condition1, condition2);
3826
3827 view.update(&mut cx, |view, cx| view.inc(cx));
3828 assert_eq!(poll_once(&mut condition1).await, None);
3829 assert_eq!(poll_once(&mut condition2).await, None);
3830
3831 view.update(&mut cx, |view, cx| view.inc(cx));
3832 assert_eq!(poll_once(&mut condition1).await, Some(()));
3833 assert_eq!(poll_once(&mut condition2).await, None);
3834
3835 view.update(&mut cx, |view, cx| view.inc(cx));
3836 assert_eq!(poll_once(&mut condition2).await, Some(()));
3837 view.update(&mut cx, |_, cx| cx.notify());
3838 }
3839
3840 #[crate::test(self)]
3841 #[should_panic]
3842 async fn test_view_condition_timeout(mut cx: TestAppContext) {
3843 struct View;
3844
3845 impl super::Entity for View {
3846 type Event = ();
3847 }
3848
3849 impl super::View for View {
3850 fn ui_name() -> &'static str {
3851 "test view"
3852 }
3853
3854 fn render(&self, _: &RenderContext<Self>) -> ElementBox {
3855 Empty::new().boxed()
3856 }
3857 }
3858
3859 let (_, view) = cx.add_window(|_| View);
3860 view.condition(&cx, |_, _| false).await;
3861 }
3862
3863 #[crate::test(self)]
3864 #[should_panic(expected = "view dropped with pending condition")]
3865 async fn test_view_condition_panic_on_drop(mut cx: TestAppContext) {
3866 struct View;
3867
3868 impl super::Entity for View {
3869 type Event = ();
3870 }
3871
3872 impl super::View for View {
3873 fn ui_name() -> &'static str {
3874 "test view"
3875 }
3876
3877 fn render(&self, _: &RenderContext<Self>) -> ElementBox {
3878 Empty::new().boxed()
3879 }
3880 }
3881
3882 let window_id = cx.add_window(|_| View).0;
3883 let view = cx.add_view(window_id, |_| View);
3884
3885 let condition = view.condition(&cx, |_, _| false);
3886 cx.update(|_| drop(view));
3887 condition.await;
3888 }
3889}