1mod async_context;
2mod entity_map;
3mod model_context;
4#[cfg(any(test, feature = "test-support"))]
5mod test_context;
6
7pub use async_context::*;
8pub use entity_map::*;
9pub use model_context::*;
10use refineable::Refineable;
11use smallvec::SmallVec;
12#[cfg(any(test, feature = "test-support"))]
13pub use test_context::*;
14
15use crate::{
16 current_platform, image_cache::ImageCache, Action, AnyBox, AnyView, AppMetadata, AssetSource,
17 ClipboardItem, Context, DispatchPhase, DisplayId, Executor, FocusEvent, FocusHandle, FocusId,
18 KeyBinding, Keymap, LayoutId, MainThread, MainThreadOnly, Pixels, Platform, Point,
19 SharedString, SubscriberSet, Subscription, SvgRenderer, Task, TextStyle, TextStyleRefinement,
20 TextSystem, View, Window, WindowContext, WindowHandle, WindowId,
21};
22use anyhow::{anyhow, Result};
23use collections::{HashMap, HashSet, VecDeque};
24use futures::{future::BoxFuture, Future};
25use parking_lot::{Mutex, RwLock};
26use slotmap::SlotMap;
27use std::{
28 any::{type_name, Any, TypeId},
29 borrow::Borrow,
30 marker::PhantomData,
31 mem,
32 ops::{Deref, DerefMut},
33 sync::{atomic::Ordering::SeqCst, Arc, Weak},
34 time::Duration,
35};
36use util::http::{self, HttpClient};
37
38pub struct App(Arc<Mutex<AppContext>>);
39
40impl App {
41 pub fn production(asset_source: Arc<dyn AssetSource>) -> Self {
42 let http_client = http::client();
43 Self::new(current_platform(), asset_source, http_client)
44 }
45
46 #[cfg(any(test, feature = "test-support"))]
47 pub fn test(seed: u64) -> Self {
48 let platform = Arc::new(crate::TestPlatform::new(seed));
49 let asset_source = Arc::new(());
50 let http_client = util::http::FakeHttpClient::with_404_response();
51 Self::new(platform, asset_source, http_client)
52 }
53
54 fn new(
55 platform: Arc<dyn Platform>,
56 asset_source: Arc<dyn AssetSource>,
57 http_client: Arc<dyn HttpClient>,
58 ) -> Self {
59 let executor = platform.executor();
60 assert!(
61 executor.is_main_thread(),
62 "must construct App on main thread"
63 );
64
65 let text_system = Arc::new(TextSystem::new(platform.text_system()));
66 let mut entities = EntityMap::new();
67 let unit_entity = entities.insert(entities.reserve(), ());
68 let app_metadata = AppMetadata {
69 os_name: platform.os_name(),
70 os_version: platform.os_version().ok(),
71 app_version: platform.app_version().ok(),
72 };
73
74 Self(Arc::new_cyclic(|this| {
75 Mutex::new(AppContext {
76 this: this.clone(),
77 text_system,
78 platform: MainThreadOnly::new(platform, executor.clone()),
79 app_metadata,
80 flushing_effects: false,
81 pending_updates: 0,
82 next_frame_callbacks: Default::default(),
83 executor,
84 svg_renderer: SvgRenderer::new(asset_source.clone()),
85 asset_source,
86 image_cache: ImageCache::new(http_client),
87 text_style_stack: Vec::new(),
88 globals_by_type: HashMap::default(),
89 unit_entity,
90 entities,
91 windows: SlotMap::with_key(),
92 keymap: Arc::new(RwLock::new(Keymap::default())),
93 global_action_listeners: HashMap::default(),
94 action_builders: HashMap::default(),
95 pending_effects: VecDeque::new(),
96 pending_notifications: HashSet::default(),
97 pending_global_notifications: HashSet::default(),
98 observers: SubscriberSet::new(),
99 event_listeners: SubscriberSet::new(),
100 release_listeners: SubscriberSet::new(),
101 global_observers: SubscriberSet::new(),
102 quit_observers: SubscriberSet::new(),
103 layout_id_buffer: Default::default(),
104 propagate_event: true,
105 active_drag: None,
106 })
107 }))
108 }
109
110 pub fn run<F>(self, on_finish_launching: F)
111 where
112 F: 'static + FnOnce(&mut MainThread<AppContext>),
113 {
114 let this = self.0.clone();
115 let platform = self.0.lock().platform.clone();
116 platform.borrow_on_main_thread().run(Box::new(move || {
117 let cx = &mut *this.lock();
118 let cx = unsafe { mem::transmute::<&mut AppContext, &mut MainThread<AppContext>>(cx) };
119 on_finish_launching(cx);
120 }));
121 }
122
123 pub fn on_open_urls<F>(&self, mut callback: F) -> &Self
124 where
125 F: 'static + FnMut(Vec<String>, &mut AppContext),
126 {
127 let this = Arc::downgrade(&self.0);
128 self.0
129 .lock()
130 .platform
131 .borrow_on_main_thread()
132 .on_open_urls(Box::new(move |urls| {
133 if let Some(app) = this.upgrade() {
134 callback(urls, &mut app.lock());
135 }
136 }));
137 self
138 }
139
140 pub fn on_reopen<F>(&self, mut callback: F) -> &Self
141 where
142 F: 'static + FnMut(&mut AppContext),
143 {
144 let this = Arc::downgrade(&self.0);
145 self.0
146 .lock()
147 .platform
148 .borrow_on_main_thread()
149 .on_reopen(Box::new(move || {
150 if let Some(app) = this.upgrade() {
151 callback(&mut app.lock());
152 }
153 }));
154 self
155 }
156
157 pub fn metadata(&self) -> AppMetadata {
158 self.0.lock().app_metadata.clone()
159 }
160
161 pub fn executor(&self) -> Executor {
162 self.0.lock().executor.clone()
163 }
164
165 pub fn text_system(&self) -> Arc<TextSystem> {
166 self.0.lock().text_system.clone()
167 }
168}
169
170type ActionBuilder = fn(json: Option<serde_json::Value>) -> anyhow::Result<Box<dyn Action>>;
171type FrameCallback = Box<dyn FnOnce(&mut WindowContext) + Send>;
172type Handler = Box<dyn FnMut(&mut AppContext) -> bool + Send + Sync + 'static>;
173type Listener = Box<dyn FnMut(&dyn Any, &mut AppContext) -> bool + Send + Sync + 'static>;
174type QuitHandler =
175 Box<dyn FnMut(&mut AppContext) -> BoxFuture<'static, ()> + Send + Sync + 'static>;
176type ReleaseListener = Box<dyn FnMut(&mut dyn Any, &mut AppContext) + Send + Sync + 'static>;
177
178pub struct AppContext {
179 this: Weak<Mutex<AppContext>>,
180 pub(crate) platform: MainThreadOnly<dyn Platform>,
181 app_metadata: AppMetadata,
182 text_system: Arc<TextSystem>,
183 flushing_effects: bool,
184 pending_updates: usize,
185 pub(crate) active_drag: Option<AnyDrag>,
186 pub(crate) next_frame_callbacks: HashMap<DisplayId, Vec<FrameCallback>>,
187 pub(crate) executor: Executor,
188 pub(crate) svg_renderer: SvgRenderer,
189 asset_source: Arc<dyn AssetSource>,
190 pub(crate) image_cache: ImageCache,
191 pub(crate) text_style_stack: Vec<TextStyleRefinement>,
192 pub(crate) globals_by_type: HashMap<TypeId, AnyBox>,
193 pub(crate) unit_entity: Handle<()>,
194 pub(crate) entities: EntityMap,
195 pub(crate) windows: SlotMap<WindowId, Option<Window>>,
196 pub(crate) keymap: Arc<RwLock<Keymap>>,
197 pub(crate) global_action_listeners:
198 HashMap<TypeId, Vec<Box<dyn Fn(&dyn Action, DispatchPhase, &mut Self) + Send + Sync>>>,
199 action_builders: HashMap<SharedString, ActionBuilder>,
200 pending_effects: VecDeque<Effect>,
201 pub(crate) pending_notifications: HashSet<EntityId>,
202 pub(crate) pending_global_notifications: HashSet<TypeId>,
203 pub(crate) observers: SubscriberSet<EntityId, Handler>,
204 pub(crate) event_listeners: SubscriberSet<EntityId, Listener>,
205 pub(crate) release_listeners: SubscriberSet<EntityId, ReleaseListener>,
206 pub(crate) global_observers: SubscriberSet<TypeId, Handler>,
207 pub(crate) quit_observers: SubscriberSet<(), QuitHandler>,
208 pub(crate) layout_id_buffer: Vec<LayoutId>, // We recycle this memory across layout requests.
209 pub(crate) propagate_event: bool,
210}
211
212impl AppContext {
213 pub fn quit(&mut self) {
214 let mut futures = Vec::new();
215
216 self.quit_observers.clone().retain(&(), |observer| {
217 futures.push(observer(self));
218 true
219 });
220
221 self.windows.clear();
222 self.flush_effects();
223
224 let futures = futures::future::join_all(futures);
225 if self
226 .executor
227 .block_with_timeout(Duration::from_millis(100), futures)
228 .is_err()
229 {
230 log::error!("timed out waiting on app_will_quit");
231 }
232 }
233
234 pub fn app_metadata(&self) -> AppMetadata {
235 self.app_metadata.clone()
236 }
237
238 pub fn refresh(&mut self) {
239 self.pending_effects.push_back(Effect::Refresh);
240 }
241
242 pub(crate) fn update<R>(&mut self, update: impl FnOnce(&mut Self) -> R) -> R {
243 self.pending_updates += 1;
244 let result = update(self);
245 if !self.flushing_effects && self.pending_updates == 1 {
246 self.flushing_effects = true;
247 self.flush_effects();
248 self.flushing_effects = false;
249 }
250 self.pending_updates -= 1;
251 result
252 }
253
254 pub(crate) fn read_window<R>(
255 &mut self,
256 id: WindowId,
257 read: impl FnOnce(&WindowContext) -> R,
258 ) -> Result<R> {
259 let window = self
260 .windows
261 .get(id)
262 .ok_or_else(|| anyhow!("window not found"))?
263 .as_ref()
264 .unwrap();
265 Ok(read(&WindowContext::immutable(self, &window)))
266 }
267
268 pub(crate) fn update_window<R>(
269 &mut self,
270 id: WindowId,
271 update: impl FnOnce(&mut WindowContext) -> R,
272 ) -> Result<R> {
273 self.update(|cx| {
274 let mut window = cx
275 .windows
276 .get_mut(id)
277 .ok_or_else(|| anyhow!("window not found"))?
278 .take()
279 .unwrap();
280
281 let result = update(&mut WindowContext::mutable(cx, &mut window));
282
283 cx.windows
284 .get_mut(id)
285 .ok_or_else(|| anyhow!("window not found"))?
286 .replace(window);
287
288 Ok(result)
289 })
290 }
291
292 pub(crate) fn push_effect(&mut self, effect: Effect) {
293 match &effect {
294 Effect::Notify { emitter } => {
295 if !self.pending_notifications.insert(*emitter) {
296 return;
297 }
298 }
299 Effect::NotifyGlobalObservers { global_type } => {
300 if !self.pending_global_notifications.insert(*global_type) {
301 return;
302 }
303 }
304 _ => {}
305 };
306
307 self.pending_effects.push_back(effect);
308 }
309
310 fn flush_effects(&mut self) {
311 loop {
312 self.release_dropped_entities();
313 self.release_dropped_focus_handles();
314 if let Some(effect) = self.pending_effects.pop_front() {
315 match effect {
316 Effect::Notify { emitter } => {
317 self.apply_notify_effect(emitter);
318 }
319 Effect::Emit { emitter, event } => self.apply_emit_effect(emitter, event),
320 Effect::FocusChanged { window_id, focused } => {
321 self.apply_focus_changed_effect(window_id, focused);
322 }
323 Effect::Refresh => {
324 self.apply_refresh_effect();
325 }
326 Effect::NotifyGlobalObservers { global_type } => {
327 self.apply_notify_global_observers_effect(global_type);
328 }
329 Effect::Defer { callback } => {
330 self.apply_defer_effect(callback);
331 }
332 }
333 } else {
334 break;
335 }
336 }
337
338 let dirty_window_ids = self
339 .windows
340 .iter()
341 .filter_map(|(window_id, window)| {
342 let window = window.as_ref().unwrap();
343 if window.dirty {
344 Some(window_id)
345 } else {
346 None
347 }
348 })
349 .collect::<SmallVec<[_; 8]>>();
350
351 for dirty_window_id in dirty_window_ids {
352 self.update_window(dirty_window_id, |cx| cx.draw()).unwrap();
353 }
354 }
355
356 fn release_dropped_entities(&mut self) {
357 loop {
358 let dropped = self.entities.take_dropped();
359 if dropped.is_empty() {
360 break;
361 }
362
363 for (entity_id, mut entity) in dropped {
364 self.observers.remove(&entity_id);
365 self.event_listeners.remove(&entity_id);
366 for mut release_callback in self.release_listeners.remove(&entity_id) {
367 release_callback(&mut entity, self);
368 }
369 }
370 }
371 }
372
373 fn release_dropped_focus_handles(&mut self) {
374 let window_ids = self.windows.keys().collect::<SmallVec<[_; 8]>>();
375 for window_id in window_ids {
376 self.update_window(window_id, |cx| {
377 let mut blur_window = false;
378 let focus = cx.window.focus;
379 cx.window.focus_handles.write().retain(|handle_id, count| {
380 if count.load(SeqCst) == 0 {
381 if focus == Some(handle_id) {
382 blur_window = true;
383 }
384 false
385 } else {
386 true
387 }
388 });
389
390 if blur_window {
391 cx.blur();
392 }
393 })
394 .unwrap();
395 }
396 }
397
398 fn apply_notify_effect(&mut self, emitter: EntityId) {
399 self.pending_notifications.remove(&emitter);
400 self.observers
401 .clone()
402 .retain(&emitter, |handler| handler(self));
403 }
404
405 fn apply_emit_effect(&mut self, emitter: EntityId, event: Box<dyn Any>) {
406 self.event_listeners
407 .clone()
408 .retain(&emitter, |handler| handler(&event, self));
409 }
410
411 fn apply_focus_changed_effect(&mut self, window_id: WindowId, focused: Option<FocusId>) {
412 self.update_window(window_id, |cx| {
413 if cx.window.focus == focused {
414 let mut listeners = mem::take(&mut cx.window.focus_listeners);
415 let focused =
416 focused.map(|id| FocusHandle::for_id(id, &cx.window.focus_handles).unwrap());
417 let blurred = cx
418 .window
419 .last_blur
420 .take()
421 .unwrap()
422 .and_then(|id| FocusHandle::for_id(id, &cx.window.focus_handles));
423 if focused.is_some() || blurred.is_some() {
424 let event = FocusEvent { focused, blurred };
425 for listener in &listeners {
426 listener(&event, cx);
427 }
428 }
429
430 listeners.extend(cx.window.focus_listeners.drain(..));
431 cx.window.focus_listeners = listeners;
432 }
433 })
434 .ok();
435 }
436
437 fn apply_refresh_effect(&mut self) {
438 for window in self.windows.values_mut() {
439 if let Some(window) = window.as_mut() {
440 window.dirty = true;
441 }
442 }
443 }
444
445 fn apply_notify_global_observers_effect(&mut self, type_id: TypeId) {
446 self.pending_global_notifications.remove(&type_id);
447 self.global_observers
448 .clone()
449 .retain(&type_id, |observer| observer(self));
450 }
451
452 fn apply_defer_effect(&mut self, callback: Box<dyn FnOnce(&mut Self) + Send + Sync + 'static>) {
453 callback(self);
454 }
455
456 pub fn to_async(&self) -> AsyncAppContext {
457 AsyncAppContext {
458 app: unsafe { mem::transmute(self.this.clone()) },
459 executor: self.executor.clone(),
460 }
461 }
462
463 pub fn executor(&self) -> &Executor {
464 &self.executor
465 }
466
467 pub fn run_on_main<R>(
468 &mut self,
469 f: impl FnOnce(&mut MainThread<AppContext>) -> R + Send + 'static,
470 ) -> Task<R>
471 where
472 R: Send + 'static,
473 {
474 if self.executor.is_main_thread() {
475 Task::ready(f(unsafe {
476 mem::transmute::<&mut AppContext, &mut MainThread<AppContext>>(self)
477 }))
478 } else {
479 let this = self.this.upgrade().unwrap();
480 self.executor.run_on_main(move || {
481 let cx = &mut *this.lock();
482 cx.update(|cx| f(unsafe { mem::transmute::<&mut Self, &mut MainThread<Self>>(cx) }))
483 })
484 }
485 }
486
487 pub fn spawn_on_main<F, R>(
488 &self,
489 f: impl FnOnce(MainThread<AsyncAppContext>) -> F + Send + 'static,
490 ) -> Task<R>
491 where
492 F: Future<Output = R> + 'static,
493 R: Send + 'static,
494 {
495 let cx = self.to_async();
496 self.executor.spawn_on_main(move || f(MainThread(cx)))
497 }
498
499 pub fn spawn<Fut, R>(&self, f: impl FnOnce(AsyncAppContext) -> Fut + Send + 'static) -> Task<R>
500 where
501 Fut: Future<Output = R> + Send + 'static,
502 R: Send + 'static,
503 {
504 let cx = self.to_async();
505 self.executor.spawn(async move {
506 let future = f(cx);
507 future.await
508 })
509 }
510
511 pub fn defer(&mut self, f: impl FnOnce(&mut AppContext) + 'static + Send + Sync) {
512 self.push_effect(Effect::Defer {
513 callback: Box::new(f),
514 });
515 }
516
517 pub fn asset_source(&self) -> &Arc<dyn AssetSource> {
518 &self.asset_source
519 }
520
521 pub fn text_system(&self) -> &Arc<TextSystem> {
522 &self.text_system
523 }
524
525 pub fn text_style(&self) -> TextStyle {
526 let mut style = TextStyle::default();
527 for refinement in &self.text_style_stack {
528 style.refine(refinement);
529 }
530 style
531 }
532
533 pub fn has_global<G: 'static>(&self) -> bool {
534 self.globals_by_type.contains_key(&TypeId::of::<G>())
535 }
536
537 pub fn global<G: 'static>(&self) -> &G {
538 self.globals_by_type
539 .get(&TypeId::of::<G>())
540 .map(|any_state| any_state.downcast_ref::<G>().unwrap())
541 .ok_or_else(|| anyhow!("no state of type {} exists", type_name::<G>()))
542 .unwrap()
543 }
544
545 pub fn try_global<G: 'static>(&self) -> Option<&G> {
546 self.globals_by_type
547 .get(&TypeId::of::<G>())
548 .map(|any_state| any_state.downcast_ref::<G>().unwrap())
549 }
550
551 pub fn global_mut<G: 'static>(&mut self) -> &mut G {
552 let global_type = TypeId::of::<G>();
553 self.push_effect(Effect::NotifyGlobalObservers { global_type });
554 self.globals_by_type
555 .get_mut(&global_type)
556 .and_then(|any_state| any_state.downcast_mut::<G>())
557 .ok_or_else(|| anyhow!("no state of type {} exists", type_name::<G>()))
558 .unwrap()
559 }
560
561 pub fn default_global<G: 'static + Default + Sync + Send>(&mut self) -> &mut G {
562 let global_type = TypeId::of::<G>();
563 self.push_effect(Effect::NotifyGlobalObservers { global_type });
564 self.globals_by_type
565 .entry(global_type)
566 .or_insert_with(|| Box::new(G::default()))
567 .downcast_mut::<G>()
568 .unwrap()
569 }
570
571 pub fn set_global<G: Any + Send + Sync>(&mut self, global: G) {
572 let global_type = TypeId::of::<G>();
573 self.push_effect(Effect::NotifyGlobalObservers { global_type });
574 self.globals_by_type.insert(global_type, Box::new(global));
575 }
576
577 pub fn update_global<G: 'static, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R {
578 let mut global = self.lease_global::<G>();
579 let result = f(&mut global, self);
580 self.end_global_lease(global);
581 result
582 }
583
584 pub fn observe_global<G: 'static>(
585 &mut self,
586 mut f: impl FnMut(&mut Self) + Send + Sync + 'static,
587 ) -> Subscription {
588 self.global_observers.insert(
589 TypeId::of::<G>(),
590 Box::new(move |cx| {
591 f(cx);
592 true
593 }),
594 )
595 }
596
597 pub(crate) fn lease_global<G: 'static>(&mut self) -> GlobalLease<G> {
598 GlobalLease::new(
599 self.globals_by_type
600 .remove(&TypeId::of::<G>())
601 .ok_or_else(|| anyhow!("no global registered of type {}", type_name::<G>()))
602 .unwrap(),
603 )
604 }
605
606 pub(crate) fn end_global_lease<G: 'static>(&mut self, lease: GlobalLease<G>) {
607 let global_type = TypeId::of::<G>();
608 self.push_effect(Effect::NotifyGlobalObservers { global_type });
609 self.globals_by_type.insert(global_type, lease.global);
610 }
611
612 pub(crate) fn push_text_style(&mut self, text_style: TextStyleRefinement) {
613 self.text_style_stack.push(text_style);
614 }
615
616 pub(crate) fn pop_text_style(&mut self) {
617 self.text_style_stack.pop();
618 }
619
620 pub fn bind_keys(&mut self, bindings: impl IntoIterator<Item = KeyBinding>) {
621 self.keymap.write().add_bindings(bindings);
622 self.pending_effects.push_back(Effect::Refresh);
623 }
624
625 pub fn on_action<A: Action>(
626 &mut self,
627 listener: impl Fn(&A, &mut Self) + Send + Sync + 'static,
628 ) {
629 self.global_action_listeners
630 .entry(TypeId::of::<A>())
631 .or_default()
632 .push(Box::new(move |action, phase, cx| {
633 if phase == DispatchPhase::Bubble {
634 let action = action.as_any().downcast_ref().unwrap();
635 listener(action, cx)
636 }
637 }));
638 }
639
640 pub fn register_action_type<A: Action>(&mut self) {
641 self.action_builders.insert(A::qualified_name(), A::build);
642 }
643
644 pub fn build_action(
645 &mut self,
646 name: &str,
647 params: Option<serde_json::Value>,
648 ) -> Result<Box<dyn Action>> {
649 let build = self
650 .action_builders
651 .get(name)
652 .ok_or_else(|| anyhow!("no action type registered for {}", name))?;
653 (build)(params)
654 }
655
656 pub fn stop_propagation(&mut self) {
657 self.propagate_event = false;
658 }
659}
660
661impl Context for AppContext {
662 type EntityContext<'a, 'w, T> = ModelContext<'a, T>;
663 type Result<T> = T;
664
665 fn entity<T: Any + Send + Sync>(
666 &mut self,
667 build_entity: impl FnOnce(&mut Self::EntityContext<'_, '_, T>) -> T,
668 ) -> Handle<T> {
669 self.update(|cx| {
670 let slot = cx.entities.reserve();
671 let entity = build_entity(&mut ModelContext::mutable(cx, slot.downgrade()));
672 cx.entities.insert(slot, entity)
673 })
674 }
675
676 fn update_entity<T: 'static, R>(
677 &mut self,
678 handle: &Handle<T>,
679 update: impl FnOnce(&mut T, &mut Self::EntityContext<'_, '_, T>) -> R,
680 ) -> R {
681 self.update(|cx| {
682 let mut entity = cx.entities.lease(handle);
683 let result = update(
684 &mut entity,
685 &mut ModelContext::mutable(cx, handle.downgrade()),
686 );
687 cx.entities.end_lease(entity);
688 result
689 })
690 }
691}
692
693impl<C> MainThread<C>
694where
695 C: Borrow<AppContext>,
696{
697 pub(crate) fn platform(&self) -> &dyn Platform {
698 self.0.borrow().platform.borrow_on_main_thread()
699 }
700
701 pub fn activate(&self, ignoring_other_apps: bool) {
702 self.platform().activate(ignoring_other_apps);
703 }
704
705 pub fn write_to_clipboard(&self, item: ClipboardItem) {
706 self.platform().write_to_clipboard(item)
707 }
708
709 pub fn read_from_clipboard(&self) -> Option<ClipboardItem> {
710 self.platform().read_from_clipboard()
711 }
712
713 pub fn write_credentials(&self, url: &str, username: &str, password: &[u8]) -> Result<()> {
714 self.platform().write_credentials(url, username, password)
715 }
716
717 pub fn read_credentials(&self, url: &str) -> Result<Option<(String, Vec<u8>)>> {
718 self.platform().read_credentials(url)
719 }
720
721 pub fn delete_credentials(&self, url: &str) -> Result<()> {
722 self.platform().delete_credentials(url)
723 }
724
725 pub fn open_url(&self, url: &str) {
726 self.platform().open_url(url);
727 }
728}
729
730impl MainThread<AppContext> {
731 fn update<R>(&mut self, update: impl FnOnce(&mut Self) -> R) -> R {
732 self.0.update(|cx| {
733 update(unsafe {
734 std::mem::transmute::<&mut AppContext, &mut MainThread<AppContext>>(cx)
735 })
736 })
737 }
738
739 pub(crate) fn update_window<R>(
740 &mut self,
741 id: WindowId,
742 update: impl FnOnce(&mut MainThread<WindowContext>) -> R,
743 ) -> Result<R> {
744 self.0.update_window(id, |cx| {
745 update(unsafe {
746 std::mem::transmute::<&mut WindowContext, &mut MainThread<WindowContext>>(cx)
747 })
748 })
749 }
750
751 pub fn open_window<V: 'static>(
752 &mut self,
753 options: crate::WindowOptions,
754 build_root_view: impl FnOnce(&mut WindowContext) -> View<V> + Send + 'static,
755 ) -> WindowHandle<V> {
756 self.update(|cx| {
757 let id = cx.windows.insert(None);
758 let handle = WindowHandle::new(id);
759 let mut window = Window::new(handle.into(), options, cx);
760 let root_view = build_root_view(&mut WindowContext::mutable(cx, &mut window));
761 window.root_view.replace(root_view.into_any());
762 cx.windows.get_mut(id).unwrap().replace(window);
763 handle
764 })
765 }
766
767 pub fn update_global<G: 'static + Send + Sync, R>(
768 &mut self,
769 update: impl FnOnce(&mut G, &mut MainThread<AppContext>) -> R,
770 ) -> R {
771 self.0.update_global(|global, cx| {
772 let cx = unsafe { mem::transmute::<&mut AppContext, &mut MainThread<AppContext>>(cx) };
773 update(global, cx)
774 })
775 }
776}
777
778pub(crate) enum Effect {
779 Notify {
780 emitter: EntityId,
781 },
782 Emit {
783 emitter: EntityId,
784 event: Box<dyn Any + Send + Sync + 'static>,
785 },
786 FocusChanged {
787 window_id: WindowId,
788 focused: Option<FocusId>,
789 },
790 Refresh,
791 NotifyGlobalObservers {
792 global_type: TypeId,
793 },
794 Defer {
795 callback: Box<dyn FnOnce(&mut AppContext) + Send + Sync + 'static>,
796 },
797}
798
799pub(crate) struct GlobalLease<G: 'static> {
800 global: AnyBox,
801 global_type: PhantomData<G>,
802}
803
804impl<G: 'static> GlobalLease<G> {
805 fn new(global: AnyBox) -> Self {
806 GlobalLease {
807 global,
808 global_type: PhantomData,
809 }
810 }
811}
812
813impl<G: 'static> Deref for GlobalLease<G> {
814 type Target = G;
815
816 fn deref(&self) -> &Self::Target {
817 self.global.downcast_ref().unwrap()
818 }
819}
820
821impl<G: 'static> DerefMut for GlobalLease<G> {
822 fn deref_mut(&mut self) -> &mut Self::Target {
823 self.global.downcast_mut().unwrap()
824 }
825}
826
827pub(crate) struct AnyDrag {
828 pub drag_handle_view: Option<AnyView>,
829 pub cursor_offset: Point<Pixels>,
830 pub state: AnyBox,
831 pub state_type: TypeId,
832}
833
834#[cfg(test)]
835mod tests {
836 use super::AppContext;
837
838 #[test]
839 fn test_app_context_send_sync() {
840 // This will not compile if `AppContext` does not implement `Send`
841 fn assert_send<T: Send>() {}
842 assert_send::<AppContext>();
843 }
844}