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