app.rs

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