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