1mod async_context;
2mod entity_map;
3mod model_context;
4
5pub use async_context::*;
6pub use entity_map::*;
7pub use model_context::*;
8use refineable::Refineable;
9use smallvec::SmallVec;
10
11use crate::{
12 current_platform, image_cache::ImageCache, Action, AnyBox, AnyView, AppMetadata, AssetSource,
13 ClipboardItem, Context, DispatchPhase, DisplayId, Executor, FocusEvent, FocusHandle, FocusId,
14 KeyBinding, Keymap, LayoutId, MainThread, MainThreadOnly, Pixels, Platform, Point,
15 SharedString, SubscriberSet, Subscription, SvgRenderer, Task, TextStyle, TextStyleRefinement,
16 TextSystem, View, Window, WindowContext, WindowHandle, WindowId,
17};
18use anyhow::{anyhow, Result};
19use collections::{HashMap, HashSet, VecDeque};
20use futures::{future::BoxFuture, Future};
21use parking_lot::{Mutex, RwLock};
22use slotmap::SlotMap;
23use std::{
24 any::{type_name, Any, TypeId},
25 borrow::Borrow,
26 marker::PhantomData,
27 mem,
28 ops::{Deref, DerefMut},
29 sync::{atomic::Ordering::SeqCst, Arc, Weak},
30 time::Duration,
31};
32use util::http::{self, HttpClient};
33
34pub struct App(Arc<Mutex<AppContext>>);
35
36impl App {
37 pub fn production(asset_source: Arc<dyn AssetSource>) -> Self {
38 let http_client = http::client();
39 Self::new(current_platform(), asset_source, http_client)
40 }
41
42 #[cfg(any(test, feature = "test"))]
43 pub fn test() -> Self {
44 let platform = Arc::new(super::TestPlatform::new());
45 let asset_source = Arc::new(());
46 let http_client = util::http::FakeHttpClient::with_404_response();
47 Self::new(platform, asset_source, http_client)
48 }
49
50 fn new(
51 platform: Arc<dyn Platform>,
52 asset_source: Arc<dyn AssetSource>,
53 http_client: Arc<dyn HttpClient>,
54 ) -> Self {
55 let executor = platform.executor();
56 assert!(
57 executor.is_main_thread(),
58 "must construct App on main thread"
59 );
60
61 let text_system = Arc::new(TextSystem::new(platform.text_system()));
62 let mut entities = EntityMap::new();
63 let unit_entity = entities.insert(entities.reserve(), ());
64 let app_metadata = AppMetadata {
65 os_name: platform.os_name(),
66 os_version: platform.os_version().ok(),
67 app_version: platform.app_version().ok(),
68 };
69 Self(Arc::new_cyclic(|this| {
70 Mutex::new(AppContext {
71 this: this.clone(),
72 text_system,
73 platform: MainThreadOnly::new(platform, executor.clone()),
74 app_metadata,
75 flushing_effects: false,
76 pending_updates: 0,
77 next_frame_callbacks: Default::default(),
78 executor,
79 svg_renderer: SvgRenderer::new(asset_source),
80 image_cache: ImageCache::new(http_client),
81 text_style_stack: Vec::new(),
82 globals_by_type: HashMap::default(),
83 unit_entity,
84 entities,
85 windows: SlotMap::with_key(),
86 keymap: Arc::new(RwLock::new(Keymap::default())),
87 global_action_listeners: HashMap::default(),
88 action_builders: HashMap::default(),
89 pending_effects: VecDeque::new(),
90 pending_notifications: HashSet::default(),
91 pending_global_notifications: HashSet::default(),
92 observers: SubscriberSet::new(),
93 event_listeners: SubscriberSet::new(),
94 release_listeners: SubscriberSet::new(),
95 global_observers: SubscriberSet::new(),
96 quit_observers: SubscriberSet::new(),
97 layout_id_buffer: Default::default(),
98 propagate_event: true,
99 active_drag: None,
100 })
101 }))
102 }
103
104 pub fn run<F>(self, on_finish_launching: F)
105 where
106 F: 'static + FnOnce(&mut MainThread<AppContext>),
107 {
108 let this = self.0.clone();
109 let platform = self.0.lock().platform.clone();
110 platform.borrow_on_main_thread().run(Box::new(move || {
111 let cx = &mut *this.lock();
112 let cx = unsafe { mem::transmute::<&mut AppContext, &mut MainThread<AppContext>>(cx) };
113 on_finish_launching(cx);
114 }));
115 }
116
117 pub fn on_open_urls<F>(&self, mut callback: F) -> &Self
118 where
119 F: 'static + FnMut(Vec<String>, &mut AppContext),
120 {
121 let this = Arc::downgrade(&self.0);
122 self.0
123 .lock()
124 .platform
125 .borrow_on_main_thread()
126 .on_open_urls(Box::new(move |urls| {
127 if let Some(app) = this.upgrade() {
128 callback(urls, &mut app.lock());
129 }
130 }));
131 self
132 }
133
134 pub fn on_reopen<F>(&self, mut callback: F) -> &Self
135 where
136 F: 'static + FnMut(&mut AppContext),
137 {
138 let this = Arc::downgrade(&self.0);
139 self.0
140 .lock()
141 .platform
142 .borrow_on_main_thread()
143 .on_reopen(Box::new(move || {
144 if let Some(app) = this.upgrade() {
145 callback(&mut app.lock());
146 }
147 }));
148 self
149 }
150
151 pub fn metadata(&self) -> AppMetadata {
152 self.0.lock().app_metadata.clone()
153 }
154
155 pub fn executor(&self) -> Executor {
156 self.0.lock().executor.clone()
157 }
158
159 pub fn text_system(&self) -> Arc<TextSystem> {
160 self.0.lock().text_system.clone()
161 }
162}
163
164type ActionBuilder = fn(json: Option<serde_json::Value>) -> anyhow::Result<Box<dyn Action>>;
165type FrameCallback = Box<dyn FnOnce(&mut WindowContext) + Send>;
166type Handler = Box<dyn Fn(&mut AppContext) -> bool + Send + Sync + 'static>;
167type Listener = Box<dyn Fn(&dyn Any, &mut AppContext) -> bool + Send + Sync + 'static>;
168type QuitHandler = Box<dyn Fn(&mut AppContext) -> BoxFuture<'static, ()> + Send + Sync + 'static>;
169type ReleaseListener = Box<dyn Fn(&mut dyn Any, &mut AppContext) + Send + Sync + 'static>;
170
171pub struct AppContext {
172 this: Weak<Mutex<AppContext>>,
173 pub(crate) platform: MainThreadOnly<dyn Platform>,
174 app_metadata: AppMetadata,
175 text_system: Arc<TextSystem>,
176 flushing_effects: bool,
177 pending_updates: usize,
178 pub(crate) active_drag: Option<AnyDrag>,
179 pub(crate) next_frame_callbacks: HashMap<DisplayId, Vec<FrameCallback>>,
180 pub(crate) executor: Executor,
181 pub(crate) svg_renderer: SvgRenderer,
182 pub(crate) image_cache: ImageCache,
183 pub(crate) text_style_stack: Vec<TextStyleRefinement>,
184 pub(crate) globals_by_type: HashMap<TypeId, AnyBox>,
185 pub(crate) unit_entity: Handle<()>,
186 pub(crate) entities: EntityMap,
187 pub(crate) windows: SlotMap<WindowId, Option<Window>>,
188 pub(crate) keymap: Arc<RwLock<Keymap>>,
189 pub(crate) global_action_listeners:
190 HashMap<TypeId, Vec<Box<dyn Fn(&dyn Action, DispatchPhase, &mut Self) + Send + Sync>>>,
191 action_builders: HashMap<SharedString, ActionBuilder>,
192 pending_effects: VecDeque<Effect>,
193 pub(crate) pending_notifications: HashSet<EntityId>,
194 pub(crate) pending_global_notifications: HashSet<TypeId>,
195 pub(crate) observers: SubscriberSet<EntityId, Handler>,
196 pub(crate) event_listeners: SubscriberSet<EntityId, Listener>,
197 pub(crate) release_listeners: SubscriberSet<EntityId, ReleaseListener>,
198 pub(crate) global_observers: SubscriberSet<TypeId, Handler>,
199 pub(crate) quit_observers: SubscriberSet<(), QuitHandler>,
200 pub(crate) layout_id_buffer: Vec<LayoutId>, // We recycle this memory across layout requests.
201 pub(crate) propagate_event: bool,
202}
203
204impl AppContext {
205 pub fn quit(&mut self) {
206 let mut futures = Vec::new();
207
208 self.quit_observers.clone().retain(&(), |observer| {
209 futures.push(observer(self));
210 true
211 });
212
213 self.windows.clear();
214 self.flush_effects();
215
216 let futures = futures::future::join_all(futures);
217 if self
218 .executor
219 .block_with_timeout(Duration::from_millis(100), futures)
220 .is_err()
221 {
222 log::error!("timed out waiting on app_will_quit");
223 }
224 }
225
226 pub fn app_metadata(&self) -> AppMetadata {
227 self.app_metadata.clone()
228 }
229
230 pub fn refresh(&mut self) {
231 self.pending_effects.push_back(Effect::Refresh);
232 }
233
234 pub(crate) fn update<R>(&mut self, update: impl FnOnce(&mut Self) -> R) -> R {
235 self.pending_updates += 1;
236 let result = update(self);
237 if !self.flushing_effects && self.pending_updates == 1 {
238 self.flushing_effects = true;
239 self.flush_effects();
240 self.flushing_effects = false;
241 }
242 self.pending_updates -= 1;
243 result
244 }
245
246 pub(crate) fn read_window<R>(
247 &mut self,
248 id: WindowId,
249 read: impl FnOnce(&WindowContext) -> R,
250 ) -> Result<R> {
251 let window = self
252 .windows
253 .get(id)
254 .ok_or_else(|| anyhow!("window not found"))?
255 .as_ref()
256 .unwrap();
257 Ok(read(&WindowContext::immutable(self, &window)))
258 }
259
260 pub(crate) fn update_window<R>(
261 &mut self,
262 id: WindowId,
263 update: impl FnOnce(&mut WindowContext) -> R,
264 ) -> Result<R> {
265 self.update(|cx| {
266 let mut window = cx
267 .windows
268 .get_mut(id)
269 .ok_or_else(|| anyhow!("window not found"))?
270 .take()
271 .unwrap();
272
273 let result = update(&mut WindowContext::mutable(cx, &mut window));
274
275 cx.windows
276 .get_mut(id)
277 .ok_or_else(|| anyhow!("window not found"))?
278 .replace(window);
279
280 Ok(result)
281 })
282 }
283
284 pub(crate) fn push_effect(&mut self, effect: Effect) {
285 match &effect {
286 Effect::Notify { emitter } => {
287 if !self.pending_notifications.insert(*emitter) {
288 return;
289 }
290 }
291 Effect::NotifyGlobalObservers { global_type } => {
292 if !self.pending_global_notifications.insert(*global_type) {
293 return;
294 }
295 }
296 _ => {}
297 };
298
299 self.pending_effects.push_back(effect);
300 }
301
302 fn flush_effects(&mut self) {
303 loop {
304 self.release_dropped_entities();
305 self.release_dropped_focus_handles();
306 if let Some(effect) = self.pending_effects.pop_front() {
307 match effect {
308 Effect::Notify { emitter } => {
309 self.apply_notify_effect(emitter);
310 }
311 Effect::Emit { emitter, event } => self.apply_emit_effect(emitter, event),
312 Effect::FocusChanged { window_id, focused } => {
313 self.apply_focus_changed_effect(window_id, focused);
314 }
315 Effect::Refresh => {
316 self.apply_refresh_effect();
317 }
318 Effect::NotifyGlobalObservers { global_type } => {
319 self.apply_notify_global_observers_effect(global_type);
320 }
321 Effect::Defer { callback } => {
322 self.apply_defer_effect(callback);
323 }
324 }
325 } else {
326 break;
327 }
328 }
329
330 let dirty_window_ids = self
331 .windows
332 .iter()
333 .filter_map(|(window_id, window)| {
334 let window = window.as_ref().unwrap();
335 if window.dirty {
336 Some(window_id)
337 } else {
338 None
339 }
340 })
341 .collect::<SmallVec<[_; 8]>>();
342
343 for dirty_window_id in dirty_window_ids {
344 self.update_window(dirty_window_id, |cx| cx.draw()).unwrap();
345 }
346 }
347
348 fn release_dropped_entities(&mut self) {
349 loop {
350 let dropped = self.entities.take_dropped();
351 if dropped.is_empty() {
352 break;
353 }
354
355 for (entity_id, mut entity) in dropped {
356 self.observers.remove(&entity_id);
357 self.event_listeners.remove(&entity_id);
358 for release_callback in self.release_listeners.remove(&entity_id) {
359 release_callback(&mut entity, self);
360 }
361 }
362 }
363 }
364
365 fn release_dropped_focus_handles(&mut self) {
366 let window_ids = self.windows.keys().collect::<SmallVec<[_; 8]>>();
367 for window_id in window_ids {
368 self.update_window(window_id, |cx| {
369 let mut blur_window = false;
370 let focus = cx.window.focus;
371 cx.window.focus_handles.write().retain(|handle_id, count| {
372 if count.load(SeqCst) == 0 {
373 if focus == Some(handle_id) {
374 blur_window = true;
375 }
376 false
377 } else {
378 true
379 }
380 });
381
382 if blur_window {
383 cx.blur();
384 }
385 })
386 .unwrap();
387 }
388 }
389
390 fn apply_notify_effect(&mut self, emitter: EntityId) {
391 self.pending_notifications.remove(&emitter);
392 self.observers
393 .clone()
394 .retain(&emitter, |handler| handler(self));
395 }
396
397 fn apply_emit_effect(&mut self, emitter: EntityId, event: Box<dyn Any>) {
398 self.event_listeners
399 .clone()
400 .retain(&emitter, |handler| handler(&event, self));
401 }
402
403 fn apply_focus_changed_effect(&mut self, window_id: WindowId, focused: Option<FocusId>) {
404 self.update_window(window_id, |cx| {
405 if cx.window.focus == focused {
406 let mut listeners = mem::take(&mut cx.window.focus_listeners);
407 let focused =
408 focused.map(|id| FocusHandle::for_id(id, &cx.window.focus_handles).unwrap());
409 let blurred = cx
410 .window
411 .last_blur
412 .take()
413 .unwrap()
414 .and_then(|id| FocusHandle::for_id(id, &cx.window.focus_handles));
415 if focused.is_some() || blurred.is_some() {
416 let event = FocusEvent { focused, blurred };
417 for listener in &listeners {
418 listener(&event, cx);
419 }
420 }
421
422 listeners.extend(cx.window.focus_listeners.drain(..));
423 cx.window.focus_listeners = listeners;
424 }
425 })
426 .ok();
427 }
428
429 fn apply_refresh_effect(&mut self) {
430 for window in self.windows.values_mut() {
431 if let Some(window) = window.as_mut() {
432 window.dirty = true;
433 }
434 }
435 }
436
437 fn apply_notify_global_observers_effect(&mut self, type_id: TypeId) {
438 self.pending_global_notifications.remove(&type_id);
439 self.global_observers
440 .clone()
441 .retain(&type_id, |observer| observer(self));
442 }
443
444 fn apply_defer_effect(&mut self, callback: Box<dyn FnOnce(&mut Self) + Send + Sync + 'static>) {
445 callback(self);
446 }
447
448 pub fn to_async(&self) -> AsyncAppContext {
449 AsyncAppContext {
450 app: unsafe { mem::transmute(self.this.clone()) },
451 executor: self.executor.clone(),
452 }
453 }
454
455 pub fn executor(&self) -> &Executor {
456 &self.executor
457 }
458
459 pub fn run_on_main<R>(
460 &mut self,
461 f: impl FnOnce(&mut MainThread<AppContext>) -> R + Send + 'static,
462 ) -> Task<R>
463 where
464 R: Send + 'static,
465 {
466 if self.executor.is_main_thread() {
467 Task::ready(f(unsafe {
468 mem::transmute::<&mut AppContext, &mut MainThread<AppContext>>(self)
469 }))
470 } else {
471 let this = self.this.upgrade().unwrap();
472 self.executor.run_on_main(move || {
473 let cx = &mut *this.lock();
474 cx.update(|cx| f(unsafe { mem::transmute::<&mut Self, &mut MainThread<Self>>(cx) }))
475 })
476 }
477 }
478
479 pub fn spawn_on_main<F, R>(
480 &self,
481 f: impl FnOnce(MainThread<AsyncAppContext>) -> F + Send + 'static,
482 ) -> Task<R>
483 where
484 F: Future<Output = R> + 'static,
485 R: Send + 'static,
486 {
487 let cx = self.to_async();
488 self.executor.spawn_on_main(move || f(MainThread(cx)))
489 }
490
491 pub fn spawn<Fut, R>(&self, f: impl FnOnce(AsyncAppContext) -> Fut + Send + 'static) -> Task<R>
492 where
493 Fut: Future<Output = R> + Send + 'static,
494 R: Send + 'static,
495 {
496 let cx = self.to_async();
497 self.executor.spawn(async move {
498 let future = f(cx);
499 future.await
500 })
501 }
502
503 pub fn defer(&mut self, f: impl FnOnce(&mut AppContext) + 'static + Send + Sync) {
504 self.push_effect(Effect::Defer {
505 callback: Box::new(f),
506 });
507 }
508
509 pub fn text_system(&self) -> &Arc<TextSystem> {
510 &self.text_system
511 }
512
513 pub fn text_style(&self) -> TextStyle {
514 let mut style = TextStyle::default();
515 for refinement in &self.text_style_stack {
516 style.refine(refinement);
517 }
518 style
519 }
520
521 pub fn has_global<G: 'static>(&self) -> bool {
522 self.globals_by_type.contains_key(&TypeId::of::<G>())
523 }
524
525 pub fn global<G: 'static>(&self) -> &G {
526 self.globals_by_type
527 .get(&TypeId::of::<G>())
528 .map(|any_state| any_state.downcast_ref::<G>().unwrap())
529 .ok_or_else(|| anyhow!("no state of type {} exists", type_name::<G>()))
530 .unwrap()
531 }
532
533 pub fn try_global<G: 'static>(&self) -> Option<&G> {
534 self.globals_by_type
535 .get(&TypeId::of::<G>())
536 .map(|any_state| any_state.downcast_ref::<G>().unwrap())
537 }
538
539 pub fn global_mut<G: 'static>(&mut self) -> &mut G {
540 let global_type = TypeId::of::<G>();
541 self.push_effect(Effect::NotifyGlobalObservers { global_type });
542 self.globals_by_type
543 .get_mut(&global_type)
544 .and_then(|any_state| any_state.downcast_mut::<G>())
545 .ok_or_else(|| anyhow!("no state of type {} exists", type_name::<G>()))
546 .unwrap()
547 }
548
549 pub fn default_global_mut<G: 'static + Default + Sync + Send>(&mut self) -> &mut G {
550 let global_type = TypeId::of::<G>();
551 self.push_effect(Effect::NotifyGlobalObservers { global_type });
552 self.globals_by_type
553 .entry(global_type)
554 .or_insert_with(|| Box::new(G::default()))
555 .downcast_mut::<G>()
556 .unwrap()
557 }
558
559 pub fn set_global<G: Any + Send + Sync>(&mut self, global: G) {
560 let global_type = TypeId::of::<G>();
561 self.push_effect(Effect::NotifyGlobalObservers { global_type });
562 self.globals_by_type.insert(global_type, Box::new(global));
563 }
564
565 pub fn update_global<G: 'static, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R {
566 let mut global = self.lease_global::<G>();
567 let result = f(&mut global, self);
568 self.end_global_lease(global);
569 result
570 }
571
572 pub fn observe_global<G: 'static>(
573 &mut self,
574 f: impl Fn(&mut Self) + Send + Sync + 'static,
575 ) -> Subscription {
576 self.global_observers.insert(
577 TypeId::of::<G>(),
578 Box::new(move |cx| {
579 f(cx);
580 true
581 }),
582 )
583 }
584
585 pub(crate) fn lease_global<G: 'static>(&mut self) -> GlobalLease<G> {
586 GlobalLease::new(
587 self.globals_by_type
588 .remove(&TypeId::of::<G>())
589 .ok_or_else(|| anyhow!("no global registered of type {}", type_name::<G>()))
590 .unwrap(),
591 )
592 }
593
594 pub(crate) fn end_global_lease<G: 'static>(&mut self, lease: GlobalLease<G>) {
595 let global_type = TypeId::of::<G>();
596 self.push_effect(Effect::NotifyGlobalObservers { global_type });
597 self.globals_by_type.insert(global_type, lease.global);
598 }
599
600 pub(crate) fn push_text_style(&mut self, text_style: TextStyleRefinement) {
601 self.text_style_stack.push(text_style);
602 }
603
604 pub(crate) fn pop_text_style(&mut self) {
605 self.text_style_stack.pop();
606 }
607
608 pub fn bind_keys(&mut self, bindings: impl IntoIterator<Item = KeyBinding>) {
609 self.keymap.write().add_bindings(bindings);
610 self.pending_effects.push_back(Effect::Refresh);
611 }
612
613 pub fn on_action<A: Action>(
614 &mut self,
615 listener: impl Fn(&A, &mut Self) + Send + Sync + 'static,
616 ) {
617 self.global_action_listeners
618 .entry(TypeId::of::<A>())
619 .or_default()
620 .push(Box::new(move |action, phase, cx| {
621 if phase == DispatchPhase::Bubble {
622 let action = action.as_any().downcast_ref().unwrap();
623 listener(action, cx)
624 }
625 }));
626 }
627
628 pub fn register_action_type<A: Action>(&mut self) {
629 self.action_builders.insert(A::qualified_name(), A::build);
630 }
631
632 pub fn build_action(
633 &mut self,
634 name: &str,
635 params: Option<serde_json::Value>,
636 ) -> Result<Box<dyn Action>> {
637 let build = self
638 .action_builders
639 .get(name)
640 .ok_or_else(|| anyhow!("no action type registered for {}", name))?;
641 (build)(params)
642 }
643
644 pub fn stop_propagation(&mut self) {
645 self.propagate_event = false;
646 }
647}
648
649impl Context for AppContext {
650 type EntityContext<'a, 'w, T> = ModelContext<'a, T>;
651 type Result<T> = T;
652
653 fn entity<T: Any + Send + Sync>(
654 &mut self,
655 build_entity: impl FnOnce(&mut Self::EntityContext<'_, '_, T>) -> T,
656 ) -> Handle<T> {
657 self.update(|cx| {
658 let slot = cx.entities.reserve();
659 let entity = build_entity(&mut ModelContext::mutable(cx, slot.downgrade()));
660 cx.entities.insert(slot, entity)
661 })
662 }
663
664 fn update_entity<T: 'static, R>(
665 &mut self,
666 handle: &Handle<T>,
667 update: impl FnOnce(&mut T, &mut Self::EntityContext<'_, '_, T>) -> R,
668 ) -> R {
669 self.update(|cx| {
670 let mut entity = cx.entities.lease(handle);
671 let result = update(
672 &mut entity,
673 &mut ModelContext::mutable(cx, handle.downgrade()),
674 );
675 cx.entities.end_lease(entity);
676 result
677 })
678 }
679}
680
681impl<C> MainThread<C>
682where
683 C: Borrow<AppContext>,
684{
685 pub(crate) fn platform(&self) -> &dyn Platform {
686 self.0.borrow().platform.borrow_on_main_thread()
687 }
688
689 pub fn activate(&self, ignoring_other_apps: bool) {
690 self.platform().activate(ignoring_other_apps);
691 }
692
693 pub fn write_to_clipboard(&self, item: ClipboardItem) {
694 self.platform().write_to_clipboard(item)
695 }
696
697 pub fn read_from_clipboard(&self) -> Option<ClipboardItem> {
698 self.platform().read_from_clipboard()
699 }
700
701 pub fn write_credentials(&self, url: &str, username: &str, password: &[u8]) -> Result<()> {
702 self.platform().write_credentials(url, username, password)
703 }
704
705 pub fn read_credentials(&self, url: &str) -> Result<Option<(String, Vec<u8>)>> {
706 self.platform().read_credentials(url)
707 }
708
709 pub fn delete_credentials(&self, url: &str) -> Result<()> {
710 self.platform().delete_credentials(url)
711 }
712
713 pub fn open_url(&self, url: &str) {
714 self.platform().open_url(url);
715 }
716}
717
718impl MainThread<AppContext> {
719 fn update<R>(&mut self, update: impl FnOnce(&mut Self) -> R) -> R {
720 self.0.update(|cx| {
721 update(unsafe {
722 std::mem::transmute::<&mut AppContext, &mut MainThread<AppContext>>(cx)
723 })
724 })
725 }
726
727 pub(crate) fn update_window<R>(
728 &mut self,
729 id: WindowId,
730 update: impl FnOnce(&mut MainThread<WindowContext>) -> R,
731 ) -> Result<R> {
732 self.0.update_window(id, |cx| {
733 update(unsafe {
734 std::mem::transmute::<&mut WindowContext, &mut MainThread<WindowContext>>(cx)
735 })
736 })
737 }
738
739 pub fn open_window<V: 'static>(
740 &mut self,
741 options: crate::WindowOptions,
742 build_root_view: impl FnOnce(&mut WindowContext) -> View<V> + Send + 'static,
743 ) -> WindowHandle<V> {
744 self.update(|cx| {
745 let id = cx.windows.insert(None);
746 let handle = WindowHandle::new(id);
747 let mut window = Window::new(handle.into(), options, cx);
748 let root_view = build_root_view(&mut WindowContext::mutable(cx, &mut window));
749 window.root_view.replace(root_view.into_any());
750 cx.windows.get_mut(id).unwrap().replace(window);
751 handle
752 })
753 }
754
755 pub fn update_global<G: 'static + Send + Sync, R>(
756 &mut self,
757 update: impl FnOnce(&mut G, &mut MainThread<AppContext>) -> R,
758 ) -> R {
759 self.0.update_global(|global, cx| {
760 let cx = unsafe { mem::transmute::<&mut AppContext, &mut MainThread<AppContext>>(cx) };
761 update(global, cx)
762 })
763 }
764}
765
766pub(crate) enum Effect {
767 Notify {
768 emitter: EntityId,
769 },
770 Emit {
771 emitter: EntityId,
772 event: Box<dyn Any + Send + Sync + 'static>,
773 },
774 FocusChanged {
775 window_id: WindowId,
776 focused: Option<FocusId>,
777 },
778 Refresh,
779 NotifyGlobalObservers {
780 global_type: TypeId,
781 },
782 Defer {
783 callback: Box<dyn FnOnce(&mut AppContext) + Send + Sync + 'static>,
784 },
785}
786
787pub(crate) struct GlobalLease<G: 'static> {
788 global: AnyBox,
789 global_type: PhantomData<G>,
790}
791
792impl<G: 'static> GlobalLease<G> {
793 fn new(global: AnyBox) -> Self {
794 GlobalLease {
795 global,
796 global_type: PhantomData,
797 }
798 }
799}
800
801impl<G: 'static> Deref for GlobalLease<G> {
802 type Target = G;
803
804 fn deref(&self) -> &Self::Target {
805 self.global.downcast_ref().unwrap()
806 }
807}
808
809impl<G: 'static> DerefMut for GlobalLease<G> {
810 fn deref_mut(&mut self) -> &mut Self::Target {
811 self.global.downcast_mut().unwrap()
812 }
813}
814
815pub(crate) struct AnyDrag {
816 pub drag_handle_view: AnyView,
817 pub cursor_offset: Point<Pixels>,
818 pub state: AnyBox,
819 pub state_type: TypeId,
820}
821
822#[cfg(test)]
823mod tests {
824 use super::AppContext;
825
826 #[test]
827 fn test_app_context_send_sync() {
828 // This will not compile if `AppContext` does not implement `Send`
829 fn assert_send<T: Send>() {}
830 assert_send::<AppContext>();
831 }
832}