1use std::{
2 any::{type_name, TypeId},
3 cell::{Ref, RefCell, RefMut},
4 marker::PhantomData,
5 ops::{Deref, DerefMut},
6 path::{Path, PathBuf},
7 rc::{Rc, Weak},
8 sync::{atomic::Ordering::SeqCst, Arc},
9 time::Duration,
10};
11
12use anyhow::{anyhow, Result};
13use derive_more::{Deref, DerefMut};
14use futures::{channel::oneshot, future::LocalBoxFuture, Future};
15use slotmap::SlotMap;
16use smol::future::FutureExt;
17
18pub use async_context::*;
19use collections::{FxHashMap, FxHashSet, VecDeque};
20pub use entity_map::*;
21use http_client::HttpClient;
22pub use model_context::*;
23#[cfg(any(test, feature = "test-support"))]
24pub use test_context::*;
25use util::ResultExt;
26
27use crate::{
28 current_platform, init_app_menus, Action, ActionRegistry, Any, AnyView, AnyWindowHandle,
29 AssetCache, AssetSource, BackgroundExecutor, ClipboardItem, Context, DispatchPhase, DisplayId,
30 Entity, EventEmitter, ForegroundExecutor, Global, KeyBinding, Keymap, Keystroke, LayoutId,
31 Menu, MenuItem, OwnedMenu, PathPromptOptions, Pixels, Platform, PlatformDisplay, Point,
32 PromptBuilder, PromptHandle, PromptLevel, Render, RenderablePromptHandle, Reservation,
33 SharedString, SubscriberSet, Subscription, SvgRenderer, Task, TextSystem, View, ViewContext,
34 Window, WindowAppearance, WindowContext, WindowHandle, WindowId,
35};
36
37mod async_context;
38mod entity_map;
39mod model_context;
40#[cfg(any(test, feature = "test-support"))]
41mod test_context;
42
43/// The duration for which futures returned from [AppContext::on_app_context] or [ModelContext::on_app_quit] can run before the application fully quits.
44pub const SHUTDOWN_TIMEOUT: Duration = Duration::from_millis(100);
45
46/// Temporary(?) wrapper around [`RefCell<AppContext>`] to help us debug any double borrows.
47/// Strongly consider removing after stabilization.
48#[doc(hidden)]
49pub struct AppCell {
50 app: RefCell<AppContext>,
51}
52
53impl AppCell {
54 #[doc(hidden)]
55 #[track_caller]
56 pub fn borrow(&self) -> AppRef {
57 if option_env!("TRACK_THREAD_BORROWS").is_some() {
58 let thread_id = std::thread::current().id();
59 eprintln!("borrowed {thread_id:?}");
60 }
61 AppRef(self.app.borrow())
62 }
63
64 #[doc(hidden)]
65 #[track_caller]
66 pub fn borrow_mut(&self) -> AppRefMut {
67 if option_env!("TRACK_THREAD_BORROWS").is_some() {
68 let thread_id = std::thread::current().id();
69 eprintln!("borrowed {thread_id:?}");
70 }
71 AppRefMut(self.app.borrow_mut())
72 }
73}
74
75#[doc(hidden)]
76#[derive(Deref, DerefMut)]
77pub struct AppRef<'a>(Ref<'a, AppContext>);
78
79impl<'a> Drop for AppRef<'a> {
80 fn drop(&mut self) {
81 if option_env!("TRACK_THREAD_BORROWS").is_some() {
82 let thread_id = std::thread::current().id();
83 eprintln!("dropped borrow from {thread_id:?}");
84 }
85 }
86}
87
88#[doc(hidden)]
89#[derive(Deref, DerefMut)]
90pub struct AppRefMut<'a>(RefMut<'a, AppContext>);
91
92impl<'a> Drop for AppRefMut<'a> {
93 fn drop(&mut self) {
94 if option_env!("TRACK_THREAD_BORROWS").is_some() {
95 let thread_id = std::thread::current().id();
96 eprintln!("dropped {thread_id:?}");
97 }
98 }
99}
100
101/// A reference to a GPUI application, typically constructed in the `main` function of your app.
102/// You won't interact with this type much outside of initial configuration and startup.
103pub struct App(Rc<AppCell>);
104
105/// Represents an application before it is fully launched. Once your app is
106/// configured, you'll start the app with `App::run`.
107impl App {
108 /// Builds an app with the given asset source.
109 #[allow(clippy::new_without_default)]
110 pub fn new() -> Self {
111 #[cfg(any(test, feature = "test-support"))]
112 log::info!("GPUI was compiled in test mode");
113
114 Self(AppContext::new(
115 current_platform(false),
116 Arc::new(()),
117 http_client::client(None, None),
118 ))
119 }
120
121 /// Build an app in headless mode. This prevents opening windows,
122 /// but makes it possible to run an application in an context like
123 /// SSH, where GUI applications are not allowed.
124 pub fn headless() -> Self {
125 Self(AppContext::new(
126 current_platform(true),
127 Arc::new(()),
128 http_client::client(None, None),
129 ))
130 }
131
132 /// Assign
133 pub fn with_assets(self, asset_source: impl AssetSource) -> Self {
134 let mut context_lock = self.0.borrow_mut();
135 let asset_source = Arc::new(asset_source);
136 context_lock.asset_source = asset_source.clone();
137 context_lock.svg_renderer = SvgRenderer::new(asset_source);
138 drop(context_lock);
139 self
140 }
141
142 /// Start the application. The provided callback will be called once the
143 /// app is fully launched.
144 pub fn run<F>(self, on_finish_launching: F)
145 where
146 F: 'static + FnOnce(&mut AppContext),
147 {
148 let this = self.0.clone();
149 let platform = self.0.borrow().platform.clone();
150 platform.run(Box::new(move || {
151 let cx = &mut *this.borrow_mut();
152 on_finish_launching(cx);
153 }));
154 }
155
156 /// Register a handler to be invoked when the platform instructs the application
157 /// to open one or more URLs.
158 pub fn on_open_urls<F>(&self, mut callback: F) -> &Self
159 where
160 F: 'static + FnMut(Vec<String>),
161 {
162 self.0.borrow().platform.on_open_urls(Box::new(callback));
163 self
164 }
165
166 /// Invokes a handler when an already-running application is launched.
167 /// On macOS, this can occur when the application icon is double-clicked or the app is launched via the dock.
168 pub fn on_reopen<F>(&self, mut callback: F) -> &Self
169 where
170 F: 'static + FnMut(&mut AppContext),
171 {
172 let this = Rc::downgrade(&self.0);
173 self.0.borrow_mut().platform.on_reopen(Box::new(move || {
174 if let Some(app) = this.upgrade() {
175 callback(&mut app.borrow_mut());
176 }
177 }));
178 self
179 }
180
181 /// Returns a handle to the [`BackgroundExecutor`] associated with this app, which can be used to spawn futures in the background.
182 pub fn background_executor(&self) -> BackgroundExecutor {
183 self.0.borrow().background_executor.clone()
184 }
185
186 /// Returns a handle to the [`ForegroundExecutor`] associated with this app, which can be used to spawn futures in the foreground.
187 pub fn foreground_executor(&self) -> ForegroundExecutor {
188 self.0.borrow().foreground_executor.clone()
189 }
190
191 /// Returns a reference to the [`TextSystem`] associated with this app.
192 pub fn text_system(&self) -> Arc<TextSystem> {
193 self.0.borrow().text_system.clone()
194 }
195
196 /// Returns the file URL of the executable with the specified name in the application bundle
197 pub fn path_for_auxiliary_executable(&self, name: &str) -> Result<PathBuf> {
198 self.0.borrow().path_for_auxiliary_executable(name)
199 }
200}
201
202type Handler = Box<dyn FnMut(&mut AppContext) -> bool + 'static>;
203type Listener = Box<dyn FnMut(&dyn Any, &mut AppContext) -> bool + 'static>;
204type KeystrokeObserver = Box<dyn FnMut(&KeystrokeEvent, &mut WindowContext) + 'static>;
205type QuitHandler = Box<dyn FnOnce(&mut AppContext) -> LocalBoxFuture<'static, ()> + 'static>;
206type ReleaseListener = Box<dyn FnOnce(&mut dyn Any, &mut AppContext) + 'static>;
207type NewViewListener = Box<dyn FnMut(AnyView, &mut WindowContext) + 'static>;
208
209/// Contains the state of the full application, and passed as a reference to a variety of callbacks.
210/// Other contexts such as [ModelContext], [WindowContext], and [ViewContext] deref to this type, making it the most general context type.
211/// You need a reference to an `AppContext` to access the state of a [Model].
212pub struct AppContext {
213 pub(crate) this: Weak<AppCell>,
214 pub(crate) platform: Rc<dyn Platform>,
215 text_system: Arc<TextSystem>,
216 flushing_effects: bool,
217 pending_updates: usize,
218 pub(crate) actions: Rc<ActionRegistry>,
219 pub(crate) active_drag: Option<AnyDrag>,
220 pub(crate) background_executor: BackgroundExecutor,
221 pub(crate) foreground_executor: ForegroundExecutor,
222 pub(crate) loading_assets: FxHashMap<(TypeId, u64), Box<dyn Any>>,
223 pub(crate) asset_cache: AssetCache,
224 asset_source: Arc<dyn AssetSource>,
225 pub(crate) svg_renderer: SvgRenderer,
226 http_client: Arc<dyn HttpClient>,
227 pub(crate) globals_by_type: FxHashMap<TypeId, Box<dyn Any>>,
228 pub(crate) entities: EntityMap,
229 pub(crate) new_view_observers: SubscriberSet<TypeId, NewViewListener>,
230 pub(crate) windows: SlotMap<WindowId, Option<Window>>,
231 pub(crate) window_handles: FxHashMap<WindowId, AnyWindowHandle>,
232 pub(crate) keymap: Rc<RefCell<Keymap>>,
233 pub(crate) global_action_listeners:
234 FxHashMap<TypeId, Vec<Rc<dyn Fn(&dyn Any, DispatchPhase, &mut Self)>>>,
235 pending_effects: VecDeque<Effect>,
236 pub(crate) pending_notifications: FxHashSet<EntityId>,
237 pub(crate) pending_global_notifications: FxHashSet<TypeId>,
238 pub(crate) observers: SubscriberSet<EntityId, Handler>,
239 // TypeId is the type of the event that the listener callback expects
240 pub(crate) event_listeners: SubscriberSet<EntityId, (TypeId, Listener)>,
241 pub(crate) keystroke_observers: SubscriberSet<(), KeystrokeObserver>,
242 pub(crate) release_listeners: SubscriberSet<EntityId, ReleaseListener>,
243 pub(crate) global_observers: SubscriberSet<TypeId, Handler>,
244 pub(crate) quit_observers: SubscriberSet<(), QuitHandler>,
245 pub(crate) layout_id_buffer: Vec<LayoutId>, // We recycle this memory across layout requests.
246 pub(crate) propagate_event: bool,
247 pub(crate) prompt_builder: Option<PromptBuilder>,
248}
249
250impl AppContext {
251 #[allow(clippy::new_ret_no_self)]
252 pub(crate) fn new(
253 platform: Rc<dyn Platform>,
254 asset_source: Arc<dyn AssetSource>,
255 http_client: Arc<dyn HttpClient>,
256 ) -> Rc<AppCell> {
257 let executor = platform.background_executor();
258 let foreground_executor = platform.foreground_executor();
259 assert!(
260 executor.is_main_thread(),
261 "must construct App on main thread"
262 );
263
264 let text_system = Arc::new(TextSystem::new(platform.text_system()));
265 let entities = EntityMap::new();
266
267 let app = Rc::new_cyclic(|this| AppCell {
268 app: RefCell::new(AppContext {
269 this: this.clone(),
270 platform: platform.clone(),
271 text_system,
272 actions: Rc::new(ActionRegistry::default()),
273 flushing_effects: false,
274 pending_updates: 0,
275 active_drag: None,
276 background_executor: executor,
277 foreground_executor,
278 svg_renderer: SvgRenderer::new(asset_source.clone()),
279 asset_cache: AssetCache::new(),
280 loading_assets: Default::default(),
281 asset_source,
282 http_client,
283 globals_by_type: FxHashMap::default(),
284 entities,
285 new_view_observers: SubscriberSet::new(),
286 window_handles: FxHashMap::default(),
287 windows: SlotMap::with_key(),
288 keymap: Rc::new(RefCell::new(Keymap::default())),
289 global_action_listeners: FxHashMap::default(),
290 pending_effects: VecDeque::new(),
291 pending_notifications: FxHashSet::default(),
292 pending_global_notifications: FxHashSet::default(),
293 observers: SubscriberSet::new(),
294 event_listeners: SubscriberSet::new(),
295 release_listeners: SubscriberSet::new(),
296 keystroke_observers: SubscriberSet::new(),
297 global_observers: SubscriberSet::new(),
298 quit_observers: SubscriberSet::new(),
299 layout_id_buffer: Default::default(),
300 propagate_event: true,
301 prompt_builder: Some(PromptBuilder::Default),
302 }),
303 });
304
305 init_app_menus(platform.as_ref(), &mut app.borrow_mut());
306
307 platform.on_quit(Box::new({
308 let cx = app.clone();
309 move || {
310 cx.borrow_mut().shutdown();
311 }
312 }));
313
314 app
315 }
316
317 /// Quit the application gracefully. Handlers registered with [`ModelContext::on_app_quit`]
318 /// will be given 100ms to complete before exiting.
319 pub fn shutdown(&mut self) {
320 let mut futures = Vec::new();
321
322 for observer in self.quit_observers.remove(&()) {
323 futures.push(observer(self));
324 }
325
326 self.windows.clear();
327 self.window_handles.clear();
328 self.flush_effects();
329
330 let futures = futures::future::join_all(futures);
331 if self
332 .background_executor
333 .block_with_timeout(SHUTDOWN_TIMEOUT, futures)
334 .is_err()
335 {
336 log::error!("timed out waiting on app_will_quit");
337 }
338 }
339
340 /// Gracefully quit the application via the platform's standard routine.
341 pub fn quit(&mut self) {
342 self.platform.quit();
343 }
344
345 /// Schedules all windows in the application to be redrawn. This can be called
346 /// multiple times in an update cycle and still result in a single redraw.
347 pub fn refresh(&mut self) {
348 self.pending_effects.push_back(Effect::Refresh);
349 }
350
351 pub(crate) fn update<R>(&mut self, update: impl FnOnce(&mut Self) -> R) -> R {
352 self.pending_updates += 1;
353 let result = update(self);
354 if !self.flushing_effects && self.pending_updates == 1 {
355 self.flushing_effects = true;
356 self.flush_effects();
357 self.flushing_effects = false;
358 }
359 self.pending_updates -= 1;
360 result
361 }
362
363 /// Arrange a callback to be invoked when the given model or view calls `notify` on its respective context.
364 pub fn observe<W, E>(
365 &mut self,
366 entity: &E,
367 mut on_notify: impl FnMut(E, &mut AppContext) + 'static,
368 ) -> Subscription
369 where
370 W: 'static,
371 E: Entity<W>,
372 {
373 self.observe_internal(entity, move |e, cx| {
374 on_notify(e, cx);
375 true
376 })
377 }
378
379 pub(crate) fn new_observer(&mut self, key: EntityId, value: Handler) -> Subscription {
380 let (subscription, activate) = self.observers.insert(key, value);
381 self.defer(move |_| activate());
382 subscription
383 }
384 pub(crate) fn observe_internal<W, E>(
385 &mut self,
386 entity: &E,
387 mut on_notify: impl FnMut(E, &mut AppContext) -> bool + 'static,
388 ) -> Subscription
389 where
390 W: 'static,
391 E: Entity<W>,
392 {
393 let entity_id = entity.entity_id();
394 let handle = entity.downgrade();
395 self.new_observer(
396 entity_id,
397 Box::new(move |cx| {
398 if let Some(handle) = E::upgrade_from(&handle) {
399 on_notify(handle, cx)
400 } else {
401 false
402 }
403 }),
404 )
405 }
406
407 /// Arrange for the given callback to be invoked whenever the given model or view emits an event of a given type.
408 /// The callback is provided a handle to the emitting entity and a reference to the emitted event.
409 pub fn subscribe<T, E, Event>(
410 &mut self,
411 entity: &E,
412 mut on_event: impl FnMut(E, &Event, &mut AppContext) + 'static,
413 ) -> Subscription
414 where
415 T: 'static + EventEmitter<Event>,
416 E: Entity<T>,
417 Event: 'static,
418 {
419 self.subscribe_internal(entity, move |entity, event, cx| {
420 on_event(entity, event, cx);
421 true
422 })
423 }
424
425 pub(crate) fn new_subscription(
426 &mut self,
427 key: EntityId,
428 value: (TypeId, Listener),
429 ) -> Subscription {
430 let (subscription, activate) = self.event_listeners.insert(key, value);
431 self.defer(move |_| activate());
432 subscription
433 }
434 pub(crate) fn subscribe_internal<T, E, Evt>(
435 &mut self,
436 entity: &E,
437 mut on_event: impl FnMut(E, &Evt, &mut AppContext) -> bool + 'static,
438 ) -> Subscription
439 where
440 T: 'static + EventEmitter<Evt>,
441 E: Entity<T>,
442 Evt: 'static,
443 {
444 let entity_id = entity.entity_id();
445 let entity = entity.downgrade();
446 self.new_subscription(
447 entity_id,
448 (
449 TypeId::of::<Evt>(),
450 Box::new(move |event, cx| {
451 let event: &Evt = event.downcast_ref().expect("invalid event type");
452 if let Some(handle) = E::upgrade_from(&entity) {
453 on_event(handle, event, cx)
454 } else {
455 false
456 }
457 }),
458 ),
459 )
460 }
461
462 /// Returns handles to all open windows in the application.
463 /// Each handle could be downcast to a handle typed for the root view of that window.
464 /// To find all windows of a given type, you could filter on
465 pub fn windows(&self) -> Vec<AnyWindowHandle> {
466 self.windows
467 .keys()
468 .flat_map(|window_id| self.window_handles.get(&window_id).copied())
469 .collect()
470 }
471
472 /// Returns the window handles ordered by their appearance on screen, front to back.
473 ///
474 /// The first window in the returned list is the active/topmost window of the application.
475 ///
476 /// This method returns None if the platform doesn't implement the method yet.
477 pub fn window_stack(&self) -> Option<Vec<AnyWindowHandle>> {
478 self.platform.window_stack()
479 }
480
481 /// Returns a handle to the window that is currently focused at the platform level, if one exists.
482 pub fn active_window(&self) -> Option<AnyWindowHandle> {
483 self.platform.active_window()
484 }
485
486 /// Opens a new window with the given option and the root view returned by the given function.
487 /// The function is invoked with a `WindowContext`, which can be used to interact with window-specific
488 /// functionality.
489 pub fn open_window<V: 'static + Render>(
490 &mut self,
491 options: crate::WindowOptions,
492 build_root_view: impl FnOnce(&mut WindowContext) -> View<V>,
493 ) -> anyhow::Result<WindowHandle<V>> {
494 self.update(|cx| {
495 let id = cx.windows.insert(None);
496 let handle = WindowHandle::new(id);
497 match Window::new(handle.into(), options, cx) {
498 Ok(mut window) => {
499 let root_view = build_root_view(&mut WindowContext::new(cx, &mut window));
500 window.root_view.replace(root_view.into());
501 WindowContext::new(cx, &mut window).defer(|cx| cx.appearance_changed());
502 cx.window_handles.insert(id, window.handle);
503 cx.windows.get_mut(id).unwrap().replace(window);
504 Ok(handle)
505 }
506 Err(e) => {
507 cx.windows.remove(id);
508 return Err(e);
509 }
510 }
511 })
512 }
513
514 /// Instructs the platform to activate the application by bringing it to the foreground.
515 pub fn activate(&self, ignoring_other_apps: bool) {
516 self.platform.activate(ignoring_other_apps);
517 }
518
519 /// Hide the application at the platform level.
520 pub fn hide(&self) {
521 self.platform.hide();
522 }
523
524 /// Hide other applications at the platform level.
525 pub fn hide_other_apps(&self) {
526 self.platform.hide_other_apps();
527 }
528
529 /// Unhide other applications at the platform level.
530 pub fn unhide_other_apps(&self) {
531 self.platform.unhide_other_apps();
532 }
533
534 /// Returns the list of currently active displays.
535 pub fn displays(&self) -> Vec<Rc<dyn PlatformDisplay>> {
536 self.platform.displays()
537 }
538
539 /// Returns the primary display that will be used for new windows.
540 pub fn primary_display(&self) -> Option<Rc<dyn PlatformDisplay>> {
541 self.platform.primary_display()
542 }
543
544 /// Returns the display with the given ID, if one exists.
545 pub fn find_display(&self, id: DisplayId) -> Option<Rc<dyn PlatformDisplay>> {
546 self.displays()
547 .iter()
548 .find(|display| display.id() == id)
549 .cloned()
550 }
551
552 /// Returns the appearance of the application's windows.
553 pub fn window_appearance(&self) -> WindowAppearance {
554 self.platform.window_appearance()
555 }
556
557 /// Writes data to the primary selection buffer.
558 /// Only available on Linux.
559 #[cfg(target_os = "linux")]
560 pub fn write_to_primary(&self, item: ClipboardItem) {
561 self.platform.write_to_primary(item)
562 }
563
564 /// Writes data to the platform clipboard.
565 pub fn write_to_clipboard(&self, item: ClipboardItem) {
566 self.platform.write_to_clipboard(item)
567 }
568
569 /// Reads data from the primary selection buffer.
570 /// Only available on Linux.
571 #[cfg(target_os = "linux")]
572 pub fn read_from_primary(&self) -> Option<ClipboardItem> {
573 self.platform.read_from_primary()
574 }
575
576 /// Reads data from the platform clipboard.
577 pub fn read_from_clipboard(&self) -> Option<ClipboardItem> {
578 self.platform.read_from_clipboard()
579 }
580
581 /// Writes credentials to the platform keychain.
582 pub fn write_credentials(
583 &self,
584 url: &str,
585 username: &str,
586 password: &[u8],
587 ) -> Task<Result<()>> {
588 self.platform.write_credentials(url, username, password)
589 }
590
591 /// Reads credentials from the platform keychain.
592 pub fn read_credentials(&self, url: &str) -> Task<Result<Option<(String, Vec<u8>)>>> {
593 self.platform.read_credentials(url)
594 }
595
596 /// Deletes credentials from the platform keychain.
597 pub fn delete_credentials(&self, url: &str) -> Task<Result<()>> {
598 self.platform.delete_credentials(url)
599 }
600
601 /// Directs the platform's default browser to open the given URL.
602 pub fn open_url(&self, url: &str) {
603 self.platform.open_url(url);
604 }
605
606 /// register_url_scheme requests that the given scheme (e.g. `zed` for `zed://` urls)
607 /// is opened by the current app.
608 /// On some platforms (e.g. macOS) you may be able to register URL schemes as part of app
609 /// distribution, but this method exists to let you register schemes at runtime.
610 pub fn register_url_scheme(&self, scheme: &str) -> Task<Result<()>> {
611 self.platform.register_url_scheme(scheme)
612 }
613
614 /// Returns the full pathname of the current app bundle.
615 /// If the app is not being run from a bundle, returns an error.
616 pub fn app_path(&self) -> Result<PathBuf> {
617 self.platform.app_path()
618 }
619
620 /// On Linux, returns the name of the compositor in use.
621 /// Is blank on other platforms.
622 pub fn compositor_name(&self) -> &'static str {
623 self.platform.compositor_name()
624 }
625
626 /// Returns the file URL of the executable with the specified name in the application bundle
627 pub fn path_for_auxiliary_executable(&self, name: &str) -> Result<PathBuf> {
628 self.platform.path_for_auxiliary_executable(name)
629 }
630
631 /// Displays a platform modal for selecting paths.
632 /// When one or more paths are selected, they'll be relayed asynchronously via the returned oneshot channel.
633 /// If cancelled, a `None` will be relayed instead.
634 /// May return an error on Linux if the file picker couldn't be opened.
635 pub fn prompt_for_paths(
636 &self,
637 options: PathPromptOptions,
638 ) -> oneshot::Receiver<Result<Option<Vec<PathBuf>>>> {
639 self.platform.prompt_for_paths(options)
640 }
641
642 /// Displays a platform modal for selecting a new path where a file can be saved.
643 /// The provided directory will be used to set the initial location.
644 /// When a path is selected, it is relayed asynchronously via the returned oneshot channel.
645 /// If cancelled, a `None` will be relayed instead.
646 /// May return an error on Linux if the file picker couldn't be opened.
647 pub fn prompt_for_new_path(
648 &self,
649 directory: &Path,
650 ) -> oneshot::Receiver<Result<Option<PathBuf>>> {
651 self.platform.prompt_for_new_path(directory)
652 }
653
654 /// Reveals the specified path at the platform level, such as in Finder on macOS.
655 pub fn reveal_path(&self, path: &Path) {
656 self.platform.reveal_path(path)
657 }
658
659 /// Returns whether the user has configured scrollbars to auto-hide at the platform level.
660 pub fn should_auto_hide_scrollbars(&self) -> bool {
661 self.platform.should_auto_hide_scrollbars()
662 }
663
664 /// Restart the application.
665 pub fn restart(&self, binary_path: Option<PathBuf>) {
666 self.platform.restart(binary_path)
667 }
668
669 /// Updates the http client assigned to GPUI
670 pub fn set_http_client(&mut self, new_client: Arc<dyn HttpClient>) {
671 self.http_client = new_client;
672 }
673
674 /// Returns the http client assigned to GPUI
675 pub fn http_client(&self) -> Arc<dyn HttpClient> {
676 self.http_client.clone()
677 }
678
679 /// Returns the SVG renderer GPUI uses
680 pub(crate) fn svg_renderer(&self) -> SvgRenderer {
681 self.svg_renderer.clone()
682 }
683
684 pub(crate) fn push_effect(&mut self, effect: Effect) {
685 match &effect {
686 Effect::Notify { emitter } => {
687 if !self.pending_notifications.insert(*emitter) {
688 return;
689 }
690 }
691 Effect::NotifyGlobalObservers { global_type } => {
692 if !self.pending_global_notifications.insert(*global_type) {
693 return;
694 }
695 }
696 _ => {}
697 };
698
699 self.pending_effects.push_back(effect);
700 }
701
702 /// Called at the end of [`AppContext::update`] to complete any side effects
703 /// such as notifying observers, emitting events, etc. Effects can themselves
704 /// cause effects, so we continue looping until all effects are processed.
705 fn flush_effects(&mut self) {
706 loop {
707 self.release_dropped_entities();
708 self.release_dropped_focus_handles();
709
710 if let Some(effect) = self.pending_effects.pop_front() {
711 match effect {
712 Effect::Notify { emitter } => {
713 self.apply_notify_effect(emitter);
714 }
715
716 Effect::Emit {
717 emitter,
718 event_type,
719 event,
720 } => self.apply_emit_effect(emitter, event_type, event),
721
722 Effect::Refresh => {
723 self.apply_refresh_effect();
724 }
725
726 Effect::NotifyGlobalObservers { global_type } => {
727 self.apply_notify_global_observers_effect(global_type);
728 }
729
730 Effect::Defer { callback } => {
731 self.apply_defer_effect(callback);
732 }
733 }
734 } else {
735 #[cfg(any(test, feature = "test-support"))]
736 for window in self
737 .windows
738 .values()
739 .filter_map(|window| {
740 let window = window.as_ref()?;
741 window.dirty.get().then_some(window.handle)
742 })
743 .collect::<Vec<_>>()
744 {
745 self.update_window(window, |_, cx| cx.draw()).unwrap();
746 }
747
748 if self.pending_effects.is_empty() {
749 break;
750 }
751 }
752 }
753 }
754
755 /// Repeatedly called during `flush_effects` to release any entities whose
756 /// reference count has become zero. We invoke any release observers before dropping
757 /// each entity.
758 fn release_dropped_entities(&mut self) {
759 loop {
760 let dropped = self.entities.take_dropped();
761 if dropped.is_empty() {
762 break;
763 }
764
765 for (entity_id, mut entity) in dropped {
766 self.observers.remove(&entity_id);
767 self.event_listeners.remove(&entity_id);
768 for release_callback in self.release_listeners.remove(&entity_id) {
769 release_callback(entity.as_mut(), self);
770 }
771 }
772 }
773 }
774
775 /// Repeatedly called during `flush_effects` to handle a focused handle being dropped.
776 fn release_dropped_focus_handles(&mut self) {
777 for window_handle in self.windows() {
778 window_handle
779 .update(self, |_, cx| {
780 let mut blur_window = false;
781 let focus = cx.window.focus;
782 cx.window.focus_handles.write().retain(|handle_id, count| {
783 if count.load(SeqCst) == 0 {
784 if focus == Some(handle_id) {
785 blur_window = true;
786 }
787 false
788 } else {
789 true
790 }
791 });
792
793 if blur_window {
794 cx.blur();
795 }
796 })
797 .unwrap();
798 }
799 }
800
801 fn apply_notify_effect(&mut self, emitter: EntityId) {
802 self.pending_notifications.remove(&emitter);
803
804 self.observers
805 .clone()
806 .retain(&emitter, |handler| handler(self));
807 }
808
809 fn apply_emit_effect(&mut self, emitter: EntityId, event_type: TypeId, event: Box<dyn Any>) {
810 self.event_listeners
811 .clone()
812 .retain(&emitter, |(stored_type, handler)| {
813 if *stored_type == event_type {
814 handler(event.as_ref(), self)
815 } else {
816 true
817 }
818 });
819 }
820
821 fn apply_refresh_effect(&mut self) {
822 for window in self.windows.values_mut() {
823 if let Some(window) = window.as_mut() {
824 window.dirty.set(true);
825 }
826 }
827 }
828
829 fn apply_notify_global_observers_effect(&mut self, type_id: TypeId) {
830 self.pending_global_notifications.remove(&type_id);
831 self.global_observers
832 .clone()
833 .retain(&type_id, |observer| observer(self));
834 }
835
836 fn apply_defer_effect(&mut self, callback: Box<dyn FnOnce(&mut Self) + 'static>) {
837 callback(self);
838 }
839
840 /// Creates an `AsyncAppContext`, which can be cloned and has a static lifetime
841 /// so it can be held across `await` points.
842 pub fn to_async(&self) -> AsyncAppContext {
843 AsyncAppContext {
844 app: self.this.clone(),
845 background_executor: self.background_executor.clone(),
846 foreground_executor: self.foreground_executor.clone(),
847 }
848 }
849
850 /// Obtains a reference to the executor, which can be used to spawn futures.
851 pub fn background_executor(&self) -> &BackgroundExecutor {
852 &self.background_executor
853 }
854
855 /// Obtains a reference to the executor, which can be used to spawn futures.
856 pub fn foreground_executor(&self) -> &ForegroundExecutor {
857 &self.foreground_executor
858 }
859
860 /// Spawns the future returned by the given function on the thread pool. The closure will be invoked
861 /// with [AsyncAppContext], which allows the application state to be accessed across await points.
862 pub fn spawn<Fut, R>(&self, f: impl FnOnce(AsyncAppContext) -> Fut) -> Task<R>
863 where
864 Fut: Future<Output = R> + 'static,
865 R: 'static,
866 {
867 self.foreground_executor.spawn(f(self.to_async()))
868 }
869
870 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
871 /// that are currently on the stack to be returned to the app.
872 pub fn defer(&mut self, f: impl FnOnce(&mut AppContext) + 'static) {
873 self.push_effect(Effect::Defer {
874 callback: Box::new(f),
875 });
876 }
877
878 /// Accessor for the application's asset source, which is provided when constructing the `App`.
879 pub fn asset_source(&self) -> &Arc<dyn AssetSource> {
880 &self.asset_source
881 }
882
883 /// Accessor for the text system.
884 pub fn text_system(&self) -> &Arc<TextSystem> {
885 &self.text_system
886 }
887
888 /// Check whether a global of the given type has been assigned.
889 pub fn has_global<G: Global>(&self) -> bool {
890 self.globals_by_type.contains_key(&TypeId::of::<G>())
891 }
892
893 /// Access the global of the given type. Panics if a global for that type has not been assigned.
894 #[track_caller]
895 pub fn global<G: Global>(&self) -> &G {
896 self.globals_by_type
897 .get(&TypeId::of::<G>())
898 .map(|any_state| any_state.downcast_ref::<G>().unwrap())
899 .ok_or_else(|| anyhow!("no state of type {} exists", type_name::<G>()))
900 .unwrap()
901 }
902
903 /// Access the global of the given type if a value has been assigned.
904 pub fn try_global<G: Global>(&self) -> Option<&G> {
905 self.globals_by_type
906 .get(&TypeId::of::<G>())
907 .map(|any_state| any_state.downcast_ref::<G>().unwrap())
908 }
909
910 /// Access the global of the given type mutably. Panics if a global for that type has not been assigned.
911 #[track_caller]
912 pub fn global_mut<G: Global>(&mut self) -> &mut G {
913 let global_type = TypeId::of::<G>();
914 self.push_effect(Effect::NotifyGlobalObservers { global_type });
915 self.globals_by_type
916 .get_mut(&global_type)
917 .and_then(|any_state| any_state.downcast_mut::<G>())
918 .ok_or_else(|| anyhow!("no state of type {} exists", type_name::<G>()))
919 .unwrap()
920 }
921
922 /// Access the global of the given type mutably. A default value is assigned if a global of this type has not
923 /// yet been assigned.
924 pub fn default_global<G: Global + Default>(&mut self) -> &mut G {
925 let global_type = TypeId::of::<G>();
926 self.push_effect(Effect::NotifyGlobalObservers { global_type });
927 self.globals_by_type
928 .entry(global_type)
929 .or_insert_with(|| Box::<G>::default())
930 .downcast_mut::<G>()
931 .unwrap()
932 }
933
934 /// Sets the value of the global of the given type.
935 pub fn set_global<G: Global>(&mut self, global: G) {
936 let global_type = TypeId::of::<G>();
937 self.push_effect(Effect::NotifyGlobalObservers { global_type });
938 self.globals_by_type.insert(global_type, Box::new(global));
939 }
940
941 /// Clear all stored globals. Does not notify global observers.
942 #[cfg(any(test, feature = "test-support"))]
943 pub fn clear_globals(&mut self) {
944 self.globals_by_type.drain();
945 }
946
947 /// Remove the global of the given type from the app context. Does not notify global observers.
948 pub fn remove_global<G: Global>(&mut self) -> G {
949 let global_type = TypeId::of::<G>();
950 self.push_effect(Effect::NotifyGlobalObservers { global_type });
951 *self
952 .globals_by_type
953 .remove(&global_type)
954 .unwrap_or_else(|| panic!("no global added for {}", std::any::type_name::<G>()))
955 .downcast()
956 .unwrap()
957 }
958
959 /// Register a callback to be invoked when a global of the given type is updated.
960 pub fn observe_global<G: Global>(
961 &mut self,
962 mut f: impl FnMut(&mut Self) + 'static,
963 ) -> Subscription {
964 let (subscription, activate) = self.global_observers.insert(
965 TypeId::of::<G>(),
966 Box::new(move |cx| {
967 f(cx);
968 true
969 }),
970 );
971 self.defer(move |_| activate());
972 subscription
973 }
974
975 /// Move the global of the given type to the stack.
976 pub(crate) fn lease_global<G: Global>(&mut self) -> GlobalLease<G> {
977 GlobalLease::new(
978 self.globals_by_type
979 .remove(&TypeId::of::<G>())
980 .ok_or_else(|| anyhow!("no global registered of type {}", type_name::<G>()))
981 .unwrap(),
982 )
983 }
984
985 /// Restore the global of the given type after it is moved to the stack.
986 pub(crate) fn end_global_lease<G: Global>(&mut self, lease: GlobalLease<G>) {
987 let global_type = TypeId::of::<G>();
988 self.push_effect(Effect::NotifyGlobalObservers { global_type });
989 self.globals_by_type.insert(global_type, lease.global);
990 }
991
992 pub(crate) fn new_view_observer(
993 &mut self,
994 key: TypeId,
995 value: NewViewListener,
996 ) -> Subscription {
997 let (subscription, activate) = self.new_view_observers.insert(key, value);
998 activate();
999 subscription
1000 }
1001 /// Arrange for the given function to be invoked whenever a view of the specified type is created.
1002 /// The function will be passed a mutable reference to the view along with an appropriate context.
1003 pub fn observe_new_views<V: 'static>(
1004 &mut self,
1005 on_new: impl 'static + Fn(&mut V, &mut ViewContext<V>),
1006 ) -> Subscription {
1007 self.new_view_observer(
1008 TypeId::of::<V>(),
1009 Box::new(move |any_view: AnyView, cx: &mut WindowContext| {
1010 any_view
1011 .downcast::<V>()
1012 .unwrap()
1013 .update(cx, |view_state, cx| {
1014 on_new(view_state, cx);
1015 })
1016 }),
1017 )
1018 }
1019
1020 /// Observe the release of a model or view. The callback is invoked after the model or view
1021 /// has no more strong references but before it has been dropped.
1022 pub fn observe_release<E, T>(
1023 &mut self,
1024 handle: &E,
1025 on_release: impl FnOnce(&mut T, &mut AppContext) + 'static,
1026 ) -> Subscription
1027 where
1028 E: Entity<T>,
1029 T: 'static,
1030 {
1031 let (subscription, activate) = self.release_listeners.insert(
1032 handle.entity_id(),
1033 Box::new(move |entity, cx| {
1034 let entity = entity.downcast_mut().expect("invalid entity type");
1035 on_release(entity, cx)
1036 }),
1037 );
1038 activate();
1039 subscription
1040 }
1041
1042 /// Register a callback to be invoked when a keystroke is received by the application
1043 /// in any window. Note that this fires after all other action and event mechanisms have resolved
1044 /// and that this API will not be invoked if the event's propagation is stopped.
1045 pub fn observe_keystrokes(
1046 &mut self,
1047 f: impl FnMut(&KeystrokeEvent, &mut WindowContext) + 'static,
1048 ) -> Subscription {
1049 fn inner(
1050 keystroke_observers: &mut SubscriberSet<(), KeystrokeObserver>,
1051 handler: KeystrokeObserver,
1052 ) -> Subscription {
1053 let (subscription, activate) = keystroke_observers.insert((), handler);
1054 activate();
1055 subscription
1056 }
1057 inner(&mut self.keystroke_observers, Box::new(f))
1058 }
1059
1060 /// Register key bindings.
1061 pub fn bind_keys(&mut self, bindings: impl IntoIterator<Item = KeyBinding>) {
1062 self.keymap.borrow_mut().add_bindings(bindings);
1063 self.pending_effects.push_back(Effect::Refresh);
1064 }
1065
1066 /// Clear all key bindings in the app.
1067 pub fn clear_key_bindings(&mut self) {
1068 self.keymap.borrow_mut().clear();
1069 self.pending_effects.push_back(Effect::Refresh);
1070 }
1071
1072 /// Register a global listener for actions invoked via the keyboard.
1073 pub fn on_action<A: Action>(&mut self, listener: impl Fn(&A, &mut Self) + 'static) {
1074 self.global_action_listeners
1075 .entry(TypeId::of::<A>())
1076 .or_default()
1077 .push(Rc::new(move |action, phase, cx| {
1078 if phase == DispatchPhase::Bubble {
1079 let action = action.downcast_ref().unwrap();
1080 listener(action, cx)
1081 }
1082 }));
1083 }
1084
1085 /// Event handlers propagate events by default. Call this method to stop dispatching to
1086 /// event handlers with a lower z-index (mouse) or higher in the tree (keyboard). This is
1087 /// the opposite of [`Self::propagate`]. It's also possible to cancel a call to [`Self::propagate`] by
1088 /// calling this method before effects are flushed.
1089 pub fn stop_propagation(&mut self) {
1090 self.propagate_event = false;
1091 }
1092
1093 /// Action handlers stop propagation by default during the bubble phase of action dispatch
1094 /// dispatching to action handlers higher in the element tree. This is the opposite of
1095 /// [`Self::stop_propagation`]. It's also possible to cancel a call to [`Self::stop_propagation`] by calling
1096 /// this method before effects are flushed.
1097 pub fn propagate(&mut self) {
1098 self.propagate_event = true;
1099 }
1100
1101 /// Build an action from some arbitrary data, typically a keymap entry.
1102 pub fn build_action(
1103 &self,
1104 name: &str,
1105 data: Option<serde_json::Value>,
1106 ) -> Result<Box<dyn Action>> {
1107 self.actions.build_action(name, data)
1108 }
1109
1110 /// Get a list of all action names that have been registered.
1111 /// in the application. Note that registration only allows for
1112 /// actions to be built dynamically, and is unrelated to binding
1113 /// actions in the element tree.
1114 pub fn all_action_names(&self) -> &[SharedString] {
1115 self.actions.all_action_names()
1116 }
1117
1118 /// Register a callback to be invoked when the application is about to quit.
1119 /// It is not possible to cancel the quit event at this point.
1120 pub fn on_app_quit<Fut>(
1121 &mut self,
1122 mut on_quit: impl FnMut(&mut AppContext) -> Fut + 'static,
1123 ) -> Subscription
1124 where
1125 Fut: 'static + Future<Output = ()>,
1126 {
1127 let (subscription, activate) = self.quit_observers.insert(
1128 (),
1129 Box::new(move |cx| {
1130 let future = on_quit(cx);
1131 future.boxed_local()
1132 }),
1133 );
1134 activate();
1135 subscription
1136 }
1137
1138 pub(crate) fn clear_pending_keystrokes(&mut self) {
1139 for window in self.windows() {
1140 window
1141 .update(self, |_, cx| {
1142 cx.clear_pending_keystrokes();
1143 })
1144 .ok();
1145 }
1146 }
1147
1148 /// Checks if the given action is bound in the current context, as defined by the app's current focus,
1149 /// the bindings in the element tree, and any global action listeners.
1150 pub fn is_action_available(&mut self, action: &dyn Action) -> bool {
1151 let mut action_available = false;
1152 if let Some(window) = self.active_window() {
1153 if let Ok(window_action_available) =
1154 window.update(self, |_, cx| cx.is_action_available(action))
1155 {
1156 action_available = window_action_available;
1157 }
1158 }
1159
1160 action_available
1161 || self
1162 .global_action_listeners
1163 .contains_key(&action.as_any().type_id())
1164 }
1165
1166 /// Sets the menu bar for this application. This will replace any existing menu bar.
1167 pub fn set_menus(&mut self, menus: Vec<Menu>) {
1168 self.platform.set_menus(menus, &self.keymap.borrow());
1169 }
1170
1171 /// Gets the menu bar for this application.
1172 pub fn get_menus(&self) -> Option<Vec<OwnedMenu>> {
1173 self.platform.get_menus()
1174 }
1175
1176 /// Sets the right click menu for the app icon in the dock
1177 pub fn set_dock_menu(&mut self, menus: Vec<MenuItem>) {
1178 self.platform.set_dock_menu(menus, &self.keymap.borrow());
1179 }
1180
1181 /// Adds given path to the bottom of the list of recent paths for the application.
1182 /// The list is usually shown on the application icon's context menu in the dock,
1183 /// and allows to open the recent files via that context menu.
1184 /// If the path is already in the list, it will be moved to the bottom of the list.
1185 pub fn add_recent_document(&mut self, path: &Path) {
1186 self.platform.add_recent_document(path);
1187 }
1188
1189 /// Dispatch an action to the currently active window or global action handler
1190 /// See [action::Action] for more information on how actions work
1191 pub fn dispatch_action(&mut self, action: &dyn Action) {
1192 if let Some(active_window) = self.active_window() {
1193 active_window
1194 .update(self, |_, cx| cx.dispatch_action(action.boxed_clone()))
1195 .log_err();
1196 } else {
1197 self.dispatch_global_action(action);
1198 }
1199 }
1200
1201 fn dispatch_global_action(&mut self, action: &dyn Action) {
1202 self.propagate_event = true;
1203
1204 if let Some(mut global_listeners) = self
1205 .global_action_listeners
1206 .remove(&action.as_any().type_id())
1207 {
1208 for listener in &global_listeners {
1209 listener(action.as_any(), DispatchPhase::Capture, self);
1210 if !self.propagate_event {
1211 break;
1212 }
1213 }
1214
1215 global_listeners.extend(
1216 self.global_action_listeners
1217 .remove(&action.as_any().type_id())
1218 .unwrap_or_default(),
1219 );
1220
1221 self.global_action_listeners
1222 .insert(action.as_any().type_id(), global_listeners);
1223 }
1224
1225 if self.propagate_event {
1226 if let Some(mut global_listeners) = self
1227 .global_action_listeners
1228 .remove(&action.as_any().type_id())
1229 {
1230 for listener in global_listeners.iter().rev() {
1231 listener(action.as_any(), DispatchPhase::Bubble, self);
1232 if !self.propagate_event {
1233 break;
1234 }
1235 }
1236
1237 global_listeners.extend(
1238 self.global_action_listeners
1239 .remove(&action.as_any().type_id())
1240 .unwrap_or_default(),
1241 );
1242
1243 self.global_action_listeners
1244 .insert(action.as_any().type_id(), global_listeners);
1245 }
1246 }
1247 }
1248
1249 /// Is there currently something being dragged?
1250 pub fn has_active_drag(&self) -> bool {
1251 self.active_drag.is_some()
1252 }
1253
1254 /// Set the prompt renderer for GPUI. This will replace the default or platform specific
1255 /// prompts with this custom implementation.
1256 pub fn set_prompt_builder(
1257 &mut self,
1258 renderer: impl Fn(
1259 PromptLevel,
1260 &str,
1261 Option<&str>,
1262 &[&str],
1263 PromptHandle,
1264 &mut WindowContext,
1265 ) -> RenderablePromptHandle
1266 + 'static,
1267 ) {
1268 self.prompt_builder = Some(PromptBuilder::Custom(Box::new(renderer)))
1269 }
1270}
1271
1272impl Context for AppContext {
1273 type Result<T> = T;
1274
1275 /// Build an entity that is owned by the application. The given function will be invoked with
1276 /// a `ModelContext` and must return an object representing the entity. A `Model` handle will be returned,
1277 /// which can be used to access the entity in a context.
1278 fn new_model<T: 'static>(
1279 &mut self,
1280 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
1281 ) -> Model<T> {
1282 self.update(|cx| {
1283 let slot = cx.entities.reserve();
1284 let entity = build_model(&mut ModelContext::new(cx, slot.downgrade()));
1285 cx.entities.insert(slot, entity)
1286 })
1287 }
1288
1289 fn reserve_model<T: 'static>(&mut self) -> Self::Result<Reservation<T>> {
1290 Reservation(self.entities.reserve())
1291 }
1292
1293 fn insert_model<T: 'static>(
1294 &mut self,
1295 reservation: Reservation<T>,
1296 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
1297 ) -> Self::Result<Model<T>> {
1298 self.update(|cx| {
1299 let slot = reservation.0;
1300 let entity = build_model(&mut ModelContext::new(cx, slot.downgrade()));
1301 cx.entities.insert(slot, entity)
1302 })
1303 }
1304
1305 /// Updates the entity referenced by the given model. The function is passed a mutable reference to the
1306 /// entity along with a `ModelContext` for the entity.
1307 fn update_model<T: 'static, R>(
1308 &mut self,
1309 model: &Model<T>,
1310 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
1311 ) -> R {
1312 self.update(|cx| {
1313 let mut entity = cx.entities.lease(model);
1314 let result = update(&mut entity, &mut ModelContext::new(cx, model.downgrade()));
1315 cx.entities.end_lease(entity);
1316 result
1317 })
1318 }
1319
1320 fn read_model<T, R>(
1321 &self,
1322 handle: &Model<T>,
1323 read: impl FnOnce(&T, &AppContext) -> R,
1324 ) -> Self::Result<R>
1325 where
1326 T: 'static,
1327 {
1328 let entity = self.entities.read(handle);
1329 read(entity, self)
1330 }
1331
1332 fn update_window<T, F>(&mut self, handle: AnyWindowHandle, update: F) -> Result<T>
1333 where
1334 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
1335 {
1336 self.update(|cx| {
1337 let mut window = cx
1338 .windows
1339 .get_mut(handle.id)
1340 .ok_or_else(|| anyhow!("window not found"))?
1341 .take()
1342 .ok_or_else(|| anyhow!("window not found"))?;
1343
1344 let root_view = window.root_view.clone().unwrap();
1345 let result = update(root_view, &mut WindowContext::new(cx, &mut window));
1346
1347 if window.removed {
1348 cx.window_handles.remove(&handle.id);
1349 cx.windows.remove(handle.id);
1350 } else {
1351 cx.windows
1352 .get_mut(handle.id)
1353 .ok_or_else(|| anyhow!("window not found"))?
1354 .replace(window);
1355 }
1356
1357 Ok(result)
1358 })
1359 }
1360
1361 fn read_window<T, R>(
1362 &self,
1363 window: &WindowHandle<T>,
1364 read: impl FnOnce(View<T>, &AppContext) -> R,
1365 ) -> Result<R>
1366 where
1367 T: 'static,
1368 {
1369 let window = self
1370 .windows
1371 .get(window.id)
1372 .ok_or_else(|| anyhow!("window not found"))?
1373 .as_ref()
1374 .unwrap();
1375
1376 let root_view = window.root_view.clone().unwrap();
1377 let view = root_view
1378 .downcast::<T>()
1379 .map_err(|_| anyhow!("root view's type has changed"))?;
1380
1381 Ok(read(view, self))
1382 }
1383}
1384
1385/// These effects are processed at the end of each application update cycle.
1386pub(crate) enum Effect {
1387 Notify {
1388 emitter: EntityId,
1389 },
1390 Emit {
1391 emitter: EntityId,
1392 event_type: TypeId,
1393 event: Box<dyn Any>,
1394 },
1395 Refresh,
1396 NotifyGlobalObservers {
1397 global_type: TypeId,
1398 },
1399 Defer {
1400 callback: Box<dyn FnOnce(&mut AppContext) + 'static>,
1401 },
1402}
1403
1404/// Wraps a global variable value during `update_global` while the value has been moved to the stack.
1405pub(crate) struct GlobalLease<G: Global> {
1406 global: Box<dyn Any>,
1407 global_type: PhantomData<G>,
1408}
1409
1410impl<G: Global> GlobalLease<G> {
1411 fn new(global: Box<dyn Any>) -> Self {
1412 GlobalLease {
1413 global,
1414 global_type: PhantomData,
1415 }
1416 }
1417}
1418
1419impl<G: Global> Deref for GlobalLease<G> {
1420 type Target = G;
1421
1422 fn deref(&self) -> &Self::Target {
1423 self.global.downcast_ref().unwrap()
1424 }
1425}
1426
1427impl<G: Global> DerefMut for GlobalLease<G> {
1428 fn deref_mut(&mut self) -> &mut Self::Target {
1429 self.global.downcast_mut().unwrap()
1430 }
1431}
1432
1433/// Contains state associated with an active drag operation, started by dragging an element
1434/// within the window or by dragging into the app from the underlying platform.
1435pub struct AnyDrag {
1436 /// The view used to render this drag
1437 pub view: AnyView,
1438
1439 /// The value of the dragged item, to be dropped
1440 pub value: Box<dyn Any>,
1441
1442 /// This is used to render the dragged item in the same place
1443 /// on the original element that the drag was initiated
1444 pub cursor_offset: Point<Pixels>,
1445}
1446
1447/// Contains state associated with a tooltip. You'll only need this struct if you're implementing
1448/// tooltip behavior on a custom element. Otherwise, use [Div::tooltip].
1449#[derive(Clone)]
1450pub struct AnyTooltip {
1451 /// The view used to display the tooltip
1452 pub view: AnyView,
1453
1454 /// The absolute position of the mouse when the tooltip was deployed.
1455 pub mouse_position: Point<Pixels>,
1456}
1457
1458/// A keystroke event, and potentially the associated action
1459#[derive(Debug)]
1460pub struct KeystrokeEvent {
1461 /// The keystroke that occurred
1462 pub keystroke: Keystroke,
1463
1464 /// The action that was resolved for the keystroke, if any
1465 pub action: Option<Box<dyn Action>>,
1466}