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, Instant},
10};
11
12use anyhow::{anyhow, Result};
13use derive_more::{Deref, DerefMut};
14use futures::{
15 channel::oneshot,
16 future::{LocalBoxFuture, Shared},
17 Future, FutureExt,
18};
19use slotmap::SlotMap;
20
21pub use async_context::*;
22use collections::{FxHashMap, FxHashSet, VecDeque};
23pub use entity_map::*;
24use http_client::HttpClient;
25pub use model_context::*;
26#[cfg(any(test, feature = "test-support"))]
27pub use test_context::*;
28use util::ResultExt;
29
30use crate::{
31 current_platform, hash, init_app_menus, Action, ActionRegistry, Any, AnyView, AnyWindowHandle,
32 Asset, AssetSource, BackgroundExecutor, ClipboardItem, Context, DispatchPhase, DisplayId,
33 Entity, EventEmitter, ForegroundExecutor, Global, KeyBinding, Keymap, Keystroke, LayoutId,
34 Menu, MenuItem, OwnedMenu, PathPromptOptions, Pixels, Platform, PlatformDisplay, Point,
35 PromptBuilder, PromptHandle, PromptLevel, Render, RenderablePromptHandle, Reservation,
36 SharedString, SubscriberSet, Subscription, SvgRenderer, Task, TextSystem, View, ViewContext,
37 Window, WindowAppearance, WindowContext, WindowHandle, WindowId,
38};
39
40mod async_context;
41mod entity_map;
42mod model_context;
43#[cfg(any(test, feature = "test-support"))]
44mod test_context;
45
46/// The duration for which futures returned from [AppContext::on_app_context] or [ModelContext::on_app_quit] can run before the application fully quits.
47pub const SHUTDOWN_TIMEOUT: Duration = Duration::from_millis(100);
48
49/// Temporary(?) wrapper around [`RefCell<AppContext>`] to help us debug any double borrows.
50/// Strongly consider removing after stabilization.
51#[doc(hidden)]
52pub struct AppCell {
53 app: RefCell<AppContext>,
54}
55
56impl AppCell {
57 #[doc(hidden)]
58 #[track_caller]
59 pub fn borrow(&self) -> AppRef {
60 if option_env!("TRACK_THREAD_BORROWS").is_some() {
61 let thread_id = std::thread::current().id();
62 eprintln!("borrowed {thread_id:?}");
63 }
64 AppRef(self.app.borrow())
65 }
66
67 #[doc(hidden)]
68 #[track_caller]
69 pub fn borrow_mut(&self) -> AppRefMut {
70 if option_env!("TRACK_THREAD_BORROWS").is_some() {
71 let thread_id = std::thread::current().id();
72 eprintln!("borrowed {thread_id:?}");
73 }
74 AppRefMut(self.app.borrow_mut())
75 }
76}
77
78#[doc(hidden)]
79#[derive(Deref, DerefMut)]
80pub struct AppRef<'a>(Ref<'a, AppContext>);
81
82impl<'a> Drop for AppRef<'a> {
83 fn drop(&mut self) {
84 if option_env!("TRACK_THREAD_BORROWS").is_some() {
85 let thread_id = std::thread::current().id();
86 eprintln!("dropped borrow from {thread_id:?}");
87 }
88 }
89}
90
91#[doc(hidden)]
92#[derive(Deref, DerefMut)]
93pub struct AppRefMut<'a>(RefMut<'a, AppContext>);
94
95impl<'a> Drop for AppRefMut<'a> {
96 fn drop(&mut self) {
97 if option_env!("TRACK_THREAD_BORROWS").is_some() {
98 let thread_id = std::thread::current().id();
99 eprintln!("dropped {thread_id:?}");
100 }
101 }
102}
103
104/// A reference to a GPUI application, typically constructed in the `main` function of your app.
105/// You won't interact with this type much outside of initial configuration and startup.
106pub struct App(Rc<AppCell>);
107
108/// Represents an application before it is fully launched. Once your app is
109/// configured, you'll start the app with `App::run`.
110impl App {
111 /// Builds an app with the given asset source.
112 #[allow(clippy::new_without_default)]
113 pub fn new() -> Self {
114 #[cfg(any(test, feature = "test-support"))]
115 log::info!("GPUI was compiled in test mode");
116
117 Self(AppContext::new(
118 current_platform(false),
119 Arc::new(()),
120 http_client::client(None, None),
121 ))
122 }
123
124 /// Build an app in headless mode. This prevents opening windows,
125 /// but makes it possible to run an application in an context like
126 /// SSH, where GUI applications are not allowed.
127 pub fn headless() -> Self {
128 Self(AppContext::new(
129 current_platform(true),
130 Arc::new(()),
131 http_client::client(None, None),
132 ))
133 }
134
135 /// Assign
136 pub fn with_assets(self, asset_source: impl AssetSource) -> Self {
137 let mut context_lock = self.0.borrow_mut();
138 let asset_source = Arc::new(asset_source);
139 context_lock.asset_source = asset_source.clone();
140 context_lock.svg_renderer = SvgRenderer::new(asset_source);
141 drop(context_lock);
142 self
143 }
144
145 /// Sets a start time for tracking time to first window draw.
146 pub fn measure_time_to_first_window_draw(self, start: Instant) -> Self {
147 self.0.borrow_mut().time_to_first_window_draw = Some(TimeToFirstWindowDraw::Pending(start));
148 self
149 }
150
151 /// Start the application. The provided callback will be called once the
152 /// app is fully launched.
153 pub fn run<F>(self, on_finish_launching: F)
154 where
155 F: 'static + FnOnce(&mut AppContext),
156 {
157 let this = self.0.clone();
158 let platform = self.0.borrow().platform.clone();
159 platform.run(Box::new(move || {
160 let cx = &mut *this.borrow_mut();
161 on_finish_launching(cx);
162 }));
163 }
164
165 /// Register a handler to be invoked when the platform instructs the application
166 /// to open one or more URLs.
167 pub fn on_open_urls<F>(&self, mut callback: F) -> &Self
168 where
169 F: 'static + FnMut(Vec<String>),
170 {
171 self.0.borrow().platform.on_open_urls(Box::new(callback));
172 self
173 }
174
175 /// Invokes a handler when an already-running application is launched.
176 /// On macOS, this can occur when the application icon is double-clicked or the app is launched via the dock.
177 pub fn on_reopen<F>(&self, mut callback: F) -> &Self
178 where
179 F: 'static + FnMut(&mut AppContext),
180 {
181 let this = Rc::downgrade(&self.0);
182 self.0.borrow_mut().platform.on_reopen(Box::new(move || {
183 if let Some(app) = this.upgrade() {
184 callback(&mut app.borrow_mut());
185 }
186 }));
187 self
188 }
189
190 /// Returns a handle to the [`BackgroundExecutor`] associated with this app, which can be used to spawn futures in the background.
191 pub fn background_executor(&self) -> BackgroundExecutor {
192 self.0.borrow().background_executor.clone()
193 }
194
195 /// Returns a handle to the [`ForegroundExecutor`] associated with this app, which can be used to spawn futures in the foreground.
196 pub fn foreground_executor(&self) -> ForegroundExecutor {
197 self.0.borrow().foreground_executor.clone()
198 }
199
200 /// Returns a reference to the [`TextSystem`] associated with this app.
201 pub fn text_system(&self) -> Arc<TextSystem> {
202 self.0.borrow().text_system.clone()
203 }
204
205 /// Returns the file URL of the executable with the specified name in the application bundle
206 pub fn path_for_auxiliary_executable(&self, name: &str) -> Result<PathBuf> {
207 self.0.borrow().path_for_auxiliary_executable(name)
208 }
209}
210
211type Handler = Box<dyn FnMut(&mut AppContext) -> bool + 'static>;
212type Listener = Box<dyn FnMut(&dyn Any, &mut AppContext) -> bool + 'static>;
213type KeystrokeObserver = Box<dyn FnMut(&KeystrokeEvent, &mut WindowContext) + 'static>;
214type QuitHandler = Box<dyn FnOnce(&mut AppContext) -> LocalBoxFuture<'static, ()> + 'static>;
215type ReleaseListener = Box<dyn FnOnce(&mut dyn Any, &mut AppContext) + 'static>;
216type NewViewListener = Box<dyn FnMut(AnyView, &mut WindowContext) + 'static>;
217
218/// Contains the state of the full application, and passed as a reference to a variety of callbacks.
219/// Other contexts such as [ModelContext], [WindowContext], and [ViewContext] deref to this type, making it the most general context type.
220/// You need a reference to an `AppContext` to access the state of a [Model].
221pub struct AppContext {
222 pub(crate) this: Weak<AppCell>,
223 pub(crate) platform: Rc<dyn Platform>,
224 text_system: Arc<TextSystem>,
225 flushing_effects: bool,
226 pending_updates: usize,
227 pub(crate) actions: Rc<ActionRegistry>,
228 pub(crate) active_drag: Option<AnyDrag>,
229 pub(crate) background_executor: BackgroundExecutor,
230 pub(crate) foreground_executor: ForegroundExecutor,
231 pub(crate) loading_assets: FxHashMap<(TypeId, u64), Box<dyn Any>>,
232 asset_source: Arc<dyn AssetSource>,
233 pub(crate) svg_renderer: SvgRenderer,
234 http_client: Arc<dyn HttpClient>,
235 pub(crate) globals_by_type: FxHashMap<TypeId, Box<dyn Any>>,
236 pub(crate) entities: EntityMap,
237 pub(crate) new_view_observers: SubscriberSet<TypeId, NewViewListener>,
238 pub(crate) windows: SlotMap<WindowId, Option<Window>>,
239 pub(crate) window_handles: FxHashMap<WindowId, AnyWindowHandle>,
240 pub(crate) keymap: Rc<RefCell<Keymap>>,
241 pub(crate) global_action_listeners:
242 FxHashMap<TypeId, Vec<Rc<dyn Fn(&dyn Any, DispatchPhase, &mut Self)>>>,
243 pending_effects: VecDeque<Effect>,
244 pub(crate) pending_notifications: FxHashSet<EntityId>,
245 pub(crate) pending_global_notifications: FxHashSet<TypeId>,
246 pub(crate) observers: SubscriberSet<EntityId, Handler>,
247 // TypeId is the type of the event that the listener callback expects
248 pub(crate) event_listeners: SubscriberSet<EntityId, (TypeId, Listener)>,
249 pub(crate) keystroke_observers: SubscriberSet<(), KeystrokeObserver>,
250 pub(crate) release_listeners: SubscriberSet<EntityId, ReleaseListener>,
251 pub(crate) global_observers: SubscriberSet<TypeId, Handler>,
252 pub(crate) quit_observers: SubscriberSet<(), QuitHandler>,
253 pub(crate) layout_id_buffer: Vec<LayoutId>, // We recycle this memory across layout requests.
254 pub(crate) propagate_event: bool,
255 pub(crate) prompt_builder: Option<PromptBuilder>,
256 pub(crate) time_to_first_window_draw: Option<TimeToFirstWindowDraw>,
257}
258
259impl AppContext {
260 #[allow(clippy::new_ret_no_self)]
261 pub(crate) fn new(
262 platform: Rc<dyn Platform>,
263 asset_source: Arc<dyn AssetSource>,
264 http_client: Arc<dyn HttpClient>,
265 ) -> Rc<AppCell> {
266 let executor = platform.background_executor();
267 let foreground_executor = platform.foreground_executor();
268 assert!(
269 executor.is_main_thread(),
270 "must construct App on main thread"
271 );
272
273 let text_system = Arc::new(TextSystem::new(platform.text_system()));
274 let entities = EntityMap::new();
275
276 let app = Rc::new_cyclic(|this| AppCell {
277 app: RefCell::new(AppContext {
278 this: this.clone(),
279 platform: platform.clone(),
280 text_system,
281 actions: Rc::new(ActionRegistry::default()),
282 flushing_effects: false,
283 pending_updates: 0,
284 active_drag: None,
285 background_executor: executor,
286 foreground_executor,
287 svg_renderer: SvgRenderer::new(asset_source.clone()),
288 loading_assets: Default::default(),
289 asset_source,
290 http_client,
291 globals_by_type: FxHashMap::default(),
292 entities,
293 new_view_observers: SubscriberSet::new(),
294 window_handles: FxHashMap::default(),
295 windows: SlotMap::with_key(),
296 keymap: Rc::new(RefCell::new(Keymap::default())),
297 global_action_listeners: FxHashMap::default(),
298 pending_effects: VecDeque::new(),
299 pending_notifications: FxHashSet::default(),
300 pending_global_notifications: FxHashSet::default(),
301 observers: SubscriberSet::new(),
302 event_listeners: SubscriberSet::new(),
303 release_listeners: SubscriberSet::new(),
304 keystroke_observers: SubscriberSet::new(),
305 global_observers: SubscriberSet::new(),
306 quit_observers: SubscriberSet::new(),
307 layout_id_buffer: Default::default(),
308 propagate_event: true,
309 prompt_builder: Some(PromptBuilder::Default),
310 time_to_first_window_draw: None,
311 }),
312 });
313
314 init_app_menus(platform.as_ref(), &mut app.borrow_mut());
315
316 platform.on_quit(Box::new({
317 let cx = app.clone();
318 move || {
319 cx.borrow_mut().shutdown();
320 }
321 }));
322
323 app
324 }
325
326 /// Quit the application gracefully. Handlers registered with [`ModelContext::on_app_quit`]
327 /// will be given 100ms to complete before exiting.
328 pub fn shutdown(&mut self) {
329 let mut futures = Vec::new();
330
331 for observer in self.quit_observers.remove(&()) {
332 futures.push(observer(self));
333 }
334
335 self.windows.clear();
336 self.window_handles.clear();
337 self.flush_effects();
338
339 let futures = futures::future::join_all(futures);
340 if self
341 .background_executor
342 .block_with_timeout(SHUTDOWN_TIMEOUT, futures)
343 .is_err()
344 {
345 log::error!("timed out waiting on app_will_quit");
346 }
347 }
348
349 /// Gracefully quit the application via the platform's standard routine.
350 pub fn quit(&mut self) {
351 self.platform.quit();
352 }
353
354 /// Schedules all windows in the application to be redrawn. This can be called
355 /// multiple times in an update cycle and still result in a single redraw.
356 pub fn refresh(&mut self) {
357 self.pending_effects.push_back(Effect::Refresh);
358 }
359
360 pub(crate) fn update<R>(&mut self, update: impl FnOnce(&mut Self) -> R) -> R {
361 self.pending_updates += 1;
362 let result = update(self);
363 if !self.flushing_effects && self.pending_updates == 1 {
364 self.flushing_effects = true;
365 self.flush_effects();
366 self.flushing_effects = false;
367 }
368 self.pending_updates -= 1;
369 result
370 }
371
372 /// Arrange a callback to be invoked when the given model or view calls `notify` on its respective context.
373 pub fn observe<W, E>(
374 &mut self,
375 entity: &E,
376 mut on_notify: impl FnMut(E, &mut AppContext) + 'static,
377 ) -> Subscription
378 where
379 W: 'static,
380 E: Entity<W>,
381 {
382 self.observe_internal(entity, move |e, cx| {
383 on_notify(e, cx);
384 true
385 })
386 }
387
388 pub(crate) fn new_observer(&mut self, key: EntityId, value: Handler) -> Subscription {
389 let (subscription, activate) = self.observers.insert(key, value);
390 self.defer(move |_| activate());
391 subscription
392 }
393 pub(crate) fn observe_internal<W, E>(
394 &mut self,
395 entity: &E,
396 mut on_notify: impl FnMut(E, &mut AppContext) -> bool + 'static,
397 ) -> Subscription
398 where
399 W: 'static,
400 E: Entity<W>,
401 {
402 let entity_id = entity.entity_id();
403 let handle = entity.downgrade();
404 self.new_observer(
405 entity_id,
406 Box::new(move |cx| {
407 if let Some(handle) = E::upgrade_from(&handle) {
408 on_notify(handle, cx)
409 } else {
410 false
411 }
412 }),
413 )
414 }
415
416 /// Arrange for the given callback to be invoked whenever the given model or view emits an event of a given type.
417 /// The callback is provided a handle to the emitting entity and a reference to the emitted event.
418 pub fn subscribe<T, E, Event>(
419 &mut self,
420 entity: &E,
421 mut on_event: impl FnMut(E, &Event, &mut AppContext) + 'static,
422 ) -> Subscription
423 where
424 T: 'static + EventEmitter<Event>,
425 E: Entity<T>,
426 Event: 'static,
427 {
428 self.subscribe_internal(entity, move |entity, event, cx| {
429 on_event(entity, event, cx);
430 true
431 })
432 }
433
434 pub(crate) fn new_subscription(
435 &mut self,
436 key: EntityId,
437 value: (TypeId, Listener),
438 ) -> Subscription {
439 let (subscription, activate) = self.event_listeners.insert(key, value);
440 self.defer(move |_| activate());
441 subscription
442 }
443 pub(crate) fn subscribe_internal<T, E, Evt>(
444 &mut self,
445 entity: &E,
446 mut on_event: impl FnMut(E, &Evt, &mut AppContext) -> bool + 'static,
447 ) -> Subscription
448 where
449 T: 'static + EventEmitter<Evt>,
450 E: Entity<T>,
451 Evt: 'static,
452 {
453 let entity_id = entity.entity_id();
454 let entity = entity.downgrade();
455 self.new_subscription(
456 entity_id,
457 (
458 TypeId::of::<Evt>(),
459 Box::new(move |event, cx| {
460 let event: &Evt = event.downcast_ref().expect("invalid event type");
461 if let Some(handle) = E::upgrade_from(&entity) {
462 on_event(handle, event, cx)
463 } else {
464 false
465 }
466 }),
467 ),
468 )
469 }
470
471 /// Returns handles to all open windows in the application.
472 /// Each handle could be downcast to a handle typed for the root view of that window.
473 /// To find all windows of a given type, you could filter on
474 pub fn windows(&self) -> Vec<AnyWindowHandle> {
475 self.windows
476 .keys()
477 .flat_map(|window_id| self.window_handles.get(&window_id).copied())
478 .collect()
479 }
480
481 /// Returns the window handles ordered by their appearance on screen, front to back.
482 ///
483 /// The first window in the returned list is the active/topmost window of the application.
484 ///
485 /// This method returns None if the platform doesn't implement the method yet.
486 pub fn window_stack(&self) -> Option<Vec<AnyWindowHandle>> {
487 self.platform.window_stack()
488 }
489
490 /// Returns a handle to the window that is currently focused at the platform level, if one exists.
491 pub fn active_window(&self) -> Option<AnyWindowHandle> {
492 self.platform.active_window()
493 }
494
495 /// Opens a new window with the given option and the root view returned by the given function.
496 /// The function is invoked with a `WindowContext`, which can be used to interact with window-specific
497 /// functionality.
498 pub fn open_window<V: 'static + Render>(
499 &mut self,
500 options: crate::WindowOptions,
501 build_root_view: impl FnOnce(&mut WindowContext) -> View<V>,
502 ) -> anyhow::Result<WindowHandle<V>> {
503 self.update(|cx| {
504 let id = cx.windows.insert(None);
505 let handle = WindowHandle::new(id);
506 match Window::new(handle.into(), options, cx) {
507 Ok(mut window) => {
508 let root_view = build_root_view(&mut WindowContext::new(cx, &mut window));
509 window.root_view.replace(root_view.into());
510 WindowContext::new(cx, &mut window).defer(|cx| cx.appearance_changed());
511 cx.window_handles.insert(id, window.handle);
512 cx.windows.get_mut(id).unwrap().replace(window);
513 Ok(handle)
514 }
515 Err(e) => {
516 cx.windows.remove(id);
517 return Err(e);
518 }
519 }
520 })
521 }
522
523 /// Instructs the platform to activate the application by bringing it to the foreground.
524 pub fn activate(&self, ignoring_other_apps: bool) {
525 self.platform.activate(ignoring_other_apps);
526 }
527
528 /// Hide the application at the platform level.
529 pub fn hide(&self) {
530 self.platform.hide();
531 }
532
533 /// Hide other applications at the platform level.
534 pub fn hide_other_apps(&self) {
535 self.platform.hide_other_apps();
536 }
537
538 /// Unhide other applications at the platform level.
539 pub fn unhide_other_apps(&self) {
540 self.platform.unhide_other_apps();
541 }
542
543 /// Returns the list of currently active displays.
544 pub fn displays(&self) -> Vec<Rc<dyn PlatformDisplay>> {
545 self.platform.displays()
546 }
547
548 /// Returns the primary display that will be used for new windows.
549 pub fn primary_display(&self) -> Option<Rc<dyn PlatformDisplay>> {
550 self.platform.primary_display()
551 }
552
553 /// Returns the display with the given ID, if one exists.
554 pub fn find_display(&self, id: DisplayId) -> Option<Rc<dyn PlatformDisplay>> {
555 self.displays()
556 .iter()
557 .find(|display| display.id() == id)
558 .cloned()
559 }
560
561 /// Returns the appearance of the application's windows.
562 pub fn window_appearance(&self) -> WindowAppearance {
563 self.platform.window_appearance()
564 }
565
566 /// Writes data to the primary selection buffer.
567 /// Only available on Linux.
568 #[cfg(target_os = "linux")]
569 pub fn write_to_primary(&self, item: ClipboardItem) {
570 self.platform.write_to_primary(item)
571 }
572
573 /// Writes data to the platform clipboard.
574 pub fn write_to_clipboard(&self, item: ClipboardItem) {
575 self.platform.write_to_clipboard(item)
576 }
577
578 /// Reads data from the primary selection buffer.
579 /// Only available on Linux.
580 #[cfg(target_os = "linux")]
581 pub fn read_from_primary(&self) -> Option<ClipboardItem> {
582 self.platform.read_from_primary()
583 }
584
585 /// Reads data from the platform clipboard.
586 pub fn read_from_clipboard(&self) -> Option<ClipboardItem> {
587 self.platform.read_from_clipboard()
588 }
589
590 /// Writes credentials to the platform keychain.
591 pub fn write_credentials(
592 &self,
593 url: &str,
594 username: &str,
595 password: &[u8],
596 ) -> Task<Result<()>> {
597 self.platform.write_credentials(url, username, password)
598 }
599
600 /// Reads credentials from the platform keychain.
601 pub fn read_credentials(&self, url: &str) -> Task<Result<Option<(String, Vec<u8>)>>> {
602 self.platform.read_credentials(url)
603 }
604
605 /// Deletes credentials from the platform keychain.
606 pub fn delete_credentials(&self, url: &str) -> Task<Result<()>> {
607 self.platform.delete_credentials(url)
608 }
609
610 /// Directs the platform's default browser to open the given URL.
611 pub fn open_url(&self, url: &str) {
612 self.platform.open_url(url);
613 }
614
615 /// register_url_scheme requests that the given scheme (e.g. `zed` for `zed://` urls)
616 /// is opened by the current app.
617 /// On some platforms (e.g. macOS) you may be able to register URL schemes as part of app
618 /// distribution, but this method exists to let you register schemes at runtime.
619 pub fn register_url_scheme(&self, scheme: &str) -> Task<Result<()>> {
620 self.platform.register_url_scheme(scheme)
621 }
622
623 /// Returns the full pathname of the current app bundle.
624 /// If the app is not being run from a bundle, returns an error.
625 pub fn app_path(&self) -> Result<PathBuf> {
626 self.platform.app_path()
627 }
628
629 /// On Linux, returns the name of the compositor in use.
630 /// Is blank on other platforms.
631 pub fn compositor_name(&self) -> &'static str {
632 self.platform.compositor_name()
633 }
634
635 /// Returns the file URL of the executable with the specified name in the application bundle
636 pub fn path_for_auxiliary_executable(&self, name: &str) -> Result<PathBuf> {
637 self.platform.path_for_auxiliary_executable(name)
638 }
639
640 /// Displays a platform modal for selecting paths.
641 /// When one or more paths are selected, they'll be relayed asynchronously via the returned oneshot channel.
642 /// If cancelled, a `None` will be relayed instead.
643 /// May return an error on Linux if the file picker couldn't be opened.
644 pub fn prompt_for_paths(
645 &self,
646 options: PathPromptOptions,
647 ) -> oneshot::Receiver<Result<Option<Vec<PathBuf>>>> {
648 self.platform.prompt_for_paths(options)
649 }
650
651 /// Displays a platform modal for selecting a new path where a file can be saved.
652 /// The provided directory will be used to set the initial location.
653 /// When a path is selected, it is relayed asynchronously via the returned oneshot channel.
654 /// If cancelled, a `None` will be relayed instead.
655 /// May return an error on Linux if the file picker couldn't be opened.
656 pub fn prompt_for_new_path(
657 &self,
658 directory: &Path,
659 ) -> oneshot::Receiver<Result<Option<PathBuf>>> {
660 self.platform.prompt_for_new_path(directory)
661 }
662
663 /// Reveals the specified path at the platform level, such as in Finder on macOS.
664 pub fn reveal_path(&self, path: &Path) {
665 self.platform.reveal_path(path)
666 }
667
668 /// Returns whether the user has configured scrollbars to auto-hide at the platform level.
669 pub fn should_auto_hide_scrollbars(&self) -> bool {
670 self.platform.should_auto_hide_scrollbars()
671 }
672
673 /// Restart the application.
674 pub fn restart(&self, binary_path: Option<PathBuf>) {
675 self.platform.restart(binary_path)
676 }
677
678 /// Updates the http client assigned to GPUI
679 pub fn set_http_client(&mut self, new_client: Arc<dyn HttpClient>) {
680 self.http_client = new_client;
681 }
682
683 /// Returns the http client assigned to GPUI
684 pub fn http_client(&self) -> Arc<dyn HttpClient> {
685 self.http_client.clone()
686 }
687
688 /// Returns the SVG renderer GPUI uses
689 pub(crate) fn svg_renderer(&self) -> SvgRenderer {
690 self.svg_renderer.clone()
691 }
692
693 pub(crate) fn push_effect(&mut self, effect: Effect) {
694 match &effect {
695 Effect::Notify { emitter } => {
696 if !self.pending_notifications.insert(*emitter) {
697 return;
698 }
699 }
700 Effect::NotifyGlobalObservers { global_type } => {
701 if !self.pending_global_notifications.insert(*global_type) {
702 return;
703 }
704 }
705 _ => {}
706 };
707
708 self.pending_effects.push_back(effect);
709 }
710
711 /// Called at the end of [`AppContext::update`] to complete any side effects
712 /// such as notifying observers, emitting events, etc. Effects can themselves
713 /// cause effects, so we continue looping until all effects are processed.
714 fn flush_effects(&mut self) {
715 loop {
716 self.release_dropped_entities();
717 self.release_dropped_focus_handles();
718
719 if let Some(effect) = self.pending_effects.pop_front() {
720 match effect {
721 Effect::Notify { emitter } => {
722 self.apply_notify_effect(emitter);
723 }
724
725 Effect::Emit {
726 emitter,
727 event_type,
728 event,
729 } => self.apply_emit_effect(emitter, event_type, event),
730
731 Effect::Refresh => {
732 self.apply_refresh_effect();
733 }
734
735 Effect::NotifyGlobalObservers { global_type } => {
736 self.apply_notify_global_observers_effect(global_type);
737 }
738
739 Effect::Defer { callback } => {
740 self.apply_defer_effect(callback);
741 }
742 }
743 } else {
744 #[cfg(any(test, feature = "test-support"))]
745 for window in self
746 .windows
747 .values()
748 .filter_map(|window| {
749 let window = window.as_ref()?;
750 window.dirty.get().then_some(window.handle)
751 })
752 .collect::<Vec<_>>()
753 {
754 self.update_window(window, |_, cx| cx.draw()).unwrap();
755 }
756
757 if self.pending_effects.is_empty() {
758 break;
759 }
760 }
761 }
762 }
763
764 /// Repeatedly called during `flush_effects` to release any entities whose
765 /// reference count has become zero. We invoke any release observers before dropping
766 /// each entity.
767 fn release_dropped_entities(&mut self) {
768 loop {
769 let dropped = self.entities.take_dropped();
770 if dropped.is_empty() {
771 break;
772 }
773
774 for (entity_id, mut entity) in dropped {
775 self.observers.remove(&entity_id);
776 self.event_listeners.remove(&entity_id);
777 for release_callback in self.release_listeners.remove(&entity_id) {
778 release_callback(entity.as_mut(), self);
779 }
780 }
781 }
782 }
783
784 /// Repeatedly called during `flush_effects` to handle a focused handle being dropped.
785 fn release_dropped_focus_handles(&mut self) {
786 for window_handle in self.windows() {
787 window_handle
788 .update(self, |_, cx| {
789 let mut blur_window = false;
790 let focus = cx.window.focus;
791 cx.window.focus_handles.write().retain(|handle_id, count| {
792 if count.load(SeqCst) == 0 {
793 if focus == Some(handle_id) {
794 blur_window = true;
795 }
796 false
797 } else {
798 true
799 }
800 });
801
802 if blur_window {
803 cx.blur();
804 }
805 })
806 .unwrap();
807 }
808 }
809
810 fn apply_notify_effect(&mut self, emitter: EntityId) {
811 self.pending_notifications.remove(&emitter);
812
813 self.observers
814 .clone()
815 .retain(&emitter, |handler| handler(self));
816 }
817
818 fn apply_emit_effect(&mut self, emitter: EntityId, event_type: TypeId, event: Box<dyn Any>) {
819 self.event_listeners
820 .clone()
821 .retain(&emitter, |(stored_type, handler)| {
822 if *stored_type == event_type {
823 handler(event.as_ref(), self)
824 } else {
825 true
826 }
827 });
828 }
829
830 fn apply_refresh_effect(&mut self) {
831 for window in self.windows.values_mut() {
832 if let Some(window) = window.as_mut() {
833 window.dirty.set(true);
834 }
835 }
836 }
837
838 fn apply_notify_global_observers_effect(&mut self, type_id: TypeId) {
839 self.pending_global_notifications.remove(&type_id);
840 self.global_observers
841 .clone()
842 .retain(&type_id, |observer| observer(self));
843 }
844
845 fn apply_defer_effect(&mut self, callback: Box<dyn FnOnce(&mut Self) + 'static>) {
846 callback(self);
847 }
848
849 /// Creates an `AsyncAppContext`, which can be cloned and has a static lifetime
850 /// so it can be held across `await` points.
851 pub fn to_async(&self) -> AsyncAppContext {
852 AsyncAppContext {
853 app: self.this.clone(),
854 background_executor: self.background_executor.clone(),
855 foreground_executor: self.foreground_executor.clone(),
856 }
857 }
858
859 /// Obtains a reference to the executor, which can be used to spawn futures.
860 pub fn background_executor(&self) -> &BackgroundExecutor {
861 &self.background_executor
862 }
863
864 /// Obtains a reference to the executor, which can be used to spawn futures.
865 pub fn foreground_executor(&self) -> &ForegroundExecutor {
866 &self.foreground_executor
867 }
868
869 /// Spawns the future returned by the given function on the thread pool. The closure will be invoked
870 /// with [AsyncAppContext], which allows the application state to be accessed across await points.
871 pub fn spawn<Fut, R>(&self, f: impl FnOnce(AsyncAppContext) -> Fut) -> Task<R>
872 where
873 Fut: Future<Output = R> + 'static,
874 R: 'static,
875 {
876 self.foreground_executor.spawn(f(self.to_async()))
877 }
878
879 /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
880 /// that are currently on the stack to be returned to the app.
881 pub fn defer(&mut self, f: impl FnOnce(&mut AppContext) + 'static) {
882 self.push_effect(Effect::Defer {
883 callback: Box::new(f),
884 });
885 }
886
887 /// Accessor for the application's asset source, which is provided when constructing the `App`.
888 pub fn asset_source(&self) -> &Arc<dyn AssetSource> {
889 &self.asset_source
890 }
891
892 /// Accessor for the text system.
893 pub fn text_system(&self) -> &Arc<TextSystem> {
894 &self.text_system
895 }
896
897 /// Check whether a global of the given type has been assigned.
898 pub fn has_global<G: Global>(&self) -> bool {
899 self.globals_by_type.contains_key(&TypeId::of::<G>())
900 }
901
902 /// Access the global of the given type. Panics if a global for that type has not been assigned.
903 #[track_caller]
904 pub fn global<G: Global>(&self) -> &G {
905 self.globals_by_type
906 .get(&TypeId::of::<G>())
907 .map(|any_state| any_state.downcast_ref::<G>().unwrap())
908 .ok_or_else(|| anyhow!("no state of type {} exists", type_name::<G>()))
909 .unwrap()
910 }
911
912 /// Access the global of the given type if a value has been assigned.
913 pub fn try_global<G: Global>(&self) -> Option<&G> {
914 self.globals_by_type
915 .get(&TypeId::of::<G>())
916 .map(|any_state| any_state.downcast_ref::<G>().unwrap())
917 }
918
919 /// Access the global of the given type mutably. Panics if a global for that type has not been assigned.
920 #[track_caller]
921 pub fn global_mut<G: Global>(&mut self) -> &mut G {
922 let global_type = TypeId::of::<G>();
923 self.push_effect(Effect::NotifyGlobalObservers { global_type });
924 self.globals_by_type
925 .get_mut(&global_type)
926 .and_then(|any_state| any_state.downcast_mut::<G>())
927 .ok_or_else(|| anyhow!("no state of type {} exists", type_name::<G>()))
928 .unwrap()
929 }
930
931 /// Access the global of the given type mutably. A default value is assigned if a global of this type has not
932 /// yet been assigned.
933 pub fn default_global<G: Global + Default>(&mut self) -> &mut G {
934 let global_type = TypeId::of::<G>();
935 self.push_effect(Effect::NotifyGlobalObservers { global_type });
936 self.globals_by_type
937 .entry(global_type)
938 .or_insert_with(|| Box::<G>::default())
939 .downcast_mut::<G>()
940 .unwrap()
941 }
942
943 /// Sets the value of the global of the given type.
944 pub fn set_global<G: Global>(&mut self, global: G) {
945 let global_type = TypeId::of::<G>();
946 self.push_effect(Effect::NotifyGlobalObservers { global_type });
947 self.globals_by_type.insert(global_type, Box::new(global));
948 }
949
950 /// Clear all stored globals. Does not notify global observers.
951 #[cfg(any(test, feature = "test-support"))]
952 pub fn clear_globals(&mut self) {
953 self.globals_by_type.drain();
954 }
955
956 /// Remove the global of the given type from the app context. Does not notify global observers.
957 pub fn remove_global<G: Global>(&mut self) -> G {
958 let global_type = TypeId::of::<G>();
959 self.push_effect(Effect::NotifyGlobalObservers { global_type });
960 *self
961 .globals_by_type
962 .remove(&global_type)
963 .unwrap_or_else(|| panic!("no global added for {}", std::any::type_name::<G>()))
964 .downcast()
965 .unwrap()
966 }
967
968 /// Register a callback to be invoked when a global of the given type is updated.
969 pub fn observe_global<G: Global>(
970 &mut self,
971 mut f: impl FnMut(&mut Self) + 'static,
972 ) -> Subscription {
973 let (subscription, activate) = self.global_observers.insert(
974 TypeId::of::<G>(),
975 Box::new(move |cx| {
976 f(cx);
977 true
978 }),
979 );
980 self.defer(move |_| activate());
981 subscription
982 }
983
984 /// Move the global of the given type to the stack.
985 pub(crate) fn lease_global<G: Global>(&mut self) -> GlobalLease<G> {
986 GlobalLease::new(
987 self.globals_by_type
988 .remove(&TypeId::of::<G>())
989 .ok_or_else(|| anyhow!("no global registered of type {}", type_name::<G>()))
990 .unwrap(),
991 )
992 }
993
994 /// Restore the global of the given type after it is moved to the stack.
995 pub(crate) fn end_global_lease<G: Global>(&mut self, lease: GlobalLease<G>) {
996 let global_type = TypeId::of::<G>();
997 self.push_effect(Effect::NotifyGlobalObservers { global_type });
998 self.globals_by_type.insert(global_type, lease.global);
999 }
1000
1001 pub(crate) fn new_view_observer(
1002 &mut self,
1003 key: TypeId,
1004 value: NewViewListener,
1005 ) -> Subscription {
1006 let (subscription, activate) = self.new_view_observers.insert(key, value);
1007 activate();
1008 subscription
1009 }
1010 /// Arrange for the given function to be invoked whenever a view of the specified type is created.
1011 /// The function will be passed a mutable reference to the view along with an appropriate context.
1012 pub fn observe_new_views<V: 'static>(
1013 &mut self,
1014 on_new: impl 'static + Fn(&mut V, &mut ViewContext<V>),
1015 ) -> Subscription {
1016 self.new_view_observer(
1017 TypeId::of::<V>(),
1018 Box::new(move |any_view: AnyView, cx: &mut WindowContext| {
1019 any_view
1020 .downcast::<V>()
1021 .unwrap()
1022 .update(cx, |view_state, cx| {
1023 on_new(view_state, cx);
1024 })
1025 }),
1026 )
1027 }
1028
1029 /// Observe the release of a model or view. The callback is invoked after the model or view
1030 /// has no more strong references but before it has been dropped.
1031 pub fn observe_release<E, T>(
1032 &mut self,
1033 handle: &E,
1034 on_release: impl FnOnce(&mut T, &mut AppContext) + 'static,
1035 ) -> Subscription
1036 where
1037 E: Entity<T>,
1038 T: 'static,
1039 {
1040 let (subscription, activate) = self.release_listeners.insert(
1041 handle.entity_id(),
1042 Box::new(move |entity, cx| {
1043 let entity = entity.downcast_mut().expect("invalid entity type");
1044 on_release(entity, cx)
1045 }),
1046 );
1047 activate();
1048 subscription
1049 }
1050
1051 /// Register a callback to be invoked when a keystroke is received by the application
1052 /// in any window. Note that this fires after all other action and event mechanisms have resolved
1053 /// and that this API will not be invoked if the event's propagation is stopped.
1054 pub fn observe_keystrokes(
1055 &mut self,
1056 f: impl FnMut(&KeystrokeEvent, &mut WindowContext) + 'static,
1057 ) -> Subscription {
1058 fn inner(
1059 keystroke_observers: &mut SubscriberSet<(), KeystrokeObserver>,
1060 handler: KeystrokeObserver,
1061 ) -> Subscription {
1062 let (subscription, activate) = keystroke_observers.insert((), handler);
1063 activate();
1064 subscription
1065 }
1066 inner(&mut self.keystroke_observers, Box::new(f))
1067 }
1068
1069 /// Register key bindings.
1070 pub fn bind_keys(&mut self, bindings: impl IntoIterator<Item = KeyBinding>) {
1071 self.keymap.borrow_mut().add_bindings(bindings);
1072 self.pending_effects.push_back(Effect::Refresh);
1073 }
1074
1075 /// Clear all key bindings in the app.
1076 pub fn clear_key_bindings(&mut self) {
1077 self.keymap.borrow_mut().clear();
1078 self.pending_effects.push_back(Effect::Refresh);
1079 }
1080
1081 /// Register a global listener for actions invoked via the keyboard.
1082 pub fn on_action<A: Action>(&mut self, listener: impl Fn(&A, &mut Self) + 'static) {
1083 self.global_action_listeners
1084 .entry(TypeId::of::<A>())
1085 .or_default()
1086 .push(Rc::new(move |action, phase, cx| {
1087 if phase == DispatchPhase::Bubble {
1088 let action = action.downcast_ref().unwrap();
1089 listener(action, cx)
1090 }
1091 }));
1092 }
1093
1094 /// Event handlers propagate events by default. Call this method to stop dispatching to
1095 /// event handlers with a lower z-index (mouse) or higher in the tree (keyboard). This is
1096 /// the opposite of [`Self::propagate`]. It's also possible to cancel a call to [`Self::propagate`] by
1097 /// calling this method before effects are flushed.
1098 pub fn stop_propagation(&mut self) {
1099 self.propagate_event = false;
1100 }
1101
1102 /// Action handlers stop propagation by default during the bubble phase of action dispatch
1103 /// dispatching to action handlers higher in the element tree. This is the opposite of
1104 /// [`Self::stop_propagation`]. It's also possible to cancel a call to [`Self::stop_propagation`] by calling
1105 /// this method before effects are flushed.
1106 pub fn propagate(&mut self) {
1107 self.propagate_event = true;
1108 }
1109
1110 /// Build an action from some arbitrary data, typically a keymap entry.
1111 pub fn build_action(
1112 &self,
1113 name: &str,
1114 data: Option<serde_json::Value>,
1115 ) -> Result<Box<dyn Action>> {
1116 self.actions.build_action(name, data)
1117 }
1118
1119 /// Get a list of all action names that have been registered.
1120 /// in the application. Note that registration only allows for
1121 /// actions to be built dynamically, and is unrelated to binding
1122 /// actions in the element tree.
1123 pub fn all_action_names(&self) -> &[SharedString] {
1124 self.actions.all_action_names()
1125 }
1126
1127 /// Register a callback to be invoked when the application is about to quit.
1128 /// It is not possible to cancel the quit event at this point.
1129 pub fn on_app_quit<Fut>(
1130 &mut self,
1131 mut on_quit: impl FnMut(&mut AppContext) -> Fut + 'static,
1132 ) -> Subscription
1133 where
1134 Fut: 'static + Future<Output = ()>,
1135 {
1136 let (subscription, activate) = self.quit_observers.insert(
1137 (),
1138 Box::new(move |cx| {
1139 let future = on_quit(cx);
1140 future.boxed_local()
1141 }),
1142 );
1143 activate();
1144 subscription
1145 }
1146
1147 pub(crate) fn clear_pending_keystrokes(&mut self) {
1148 for window in self.windows() {
1149 window
1150 .update(self, |_, cx| {
1151 cx.clear_pending_keystrokes();
1152 })
1153 .ok();
1154 }
1155 }
1156
1157 /// Checks if the given action is bound in the current context, as defined by the app's current focus,
1158 /// the bindings in the element tree, and any global action listeners.
1159 pub fn is_action_available(&mut self, action: &dyn Action) -> bool {
1160 let mut action_available = false;
1161 if let Some(window) = self.active_window() {
1162 if let Ok(window_action_available) =
1163 window.update(self, |_, cx| cx.is_action_available(action))
1164 {
1165 action_available = window_action_available;
1166 }
1167 }
1168
1169 action_available
1170 || self
1171 .global_action_listeners
1172 .contains_key(&action.as_any().type_id())
1173 }
1174
1175 /// Sets the menu bar for this application. This will replace any existing menu bar.
1176 pub fn set_menus(&mut self, menus: Vec<Menu>) {
1177 self.platform.set_menus(menus, &self.keymap.borrow());
1178 }
1179
1180 /// Gets the menu bar for this application.
1181 pub fn get_menus(&self) -> Option<Vec<OwnedMenu>> {
1182 self.platform.get_menus()
1183 }
1184
1185 /// Sets the right click menu for the app icon in the dock
1186 pub fn set_dock_menu(&mut self, menus: Vec<MenuItem>) {
1187 self.platform.set_dock_menu(menus, &self.keymap.borrow());
1188 }
1189
1190 /// Adds given path to the bottom of the list of recent paths for the application.
1191 /// The list is usually shown on the application icon's context menu in the dock,
1192 /// and allows to open the recent files via that context menu.
1193 /// If the path is already in the list, it will be moved to the bottom of the list.
1194 pub fn add_recent_document(&mut self, path: &Path) {
1195 self.platform.add_recent_document(path);
1196 }
1197
1198 /// Dispatch an action to the currently active window or global action handler
1199 /// See [action::Action] for more information on how actions work
1200 pub fn dispatch_action(&mut self, action: &dyn Action) {
1201 if let Some(active_window) = self.active_window() {
1202 active_window
1203 .update(self, |_, cx| cx.dispatch_action(action.boxed_clone()))
1204 .log_err();
1205 } else {
1206 self.dispatch_global_action(action);
1207 }
1208 }
1209
1210 fn dispatch_global_action(&mut self, action: &dyn Action) {
1211 self.propagate_event = true;
1212
1213 if let Some(mut global_listeners) = self
1214 .global_action_listeners
1215 .remove(&action.as_any().type_id())
1216 {
1217 for listener in &global_listeners {
1218 listener(action.as_any(), DispatchPhase::Capture, self);
1219 if !self.propagate_event {
1220 break;
1221 }
1222 }
1223
1224 global_listeners.extend(
1225 self.global_action_listeners
1226 .remove(&action.as_any().type_id())
1227 .unwrap_or_default(),
1228 );
1229
1230 self.global_action_listeners
1231 .insert(action.as_any().type_id(), global_listeners);
1232 }
1233
1234 if self.propagate_event {
1235 if let Some(mut global_listeners) = self
1236 .global_action_listeners
1237 .remove(&action.as_any().type_id())
1238 {
1239 for listener in global_listeners.iter().rev() {
1240 listener(action.as_any(), DispatchPhase::Bubble, self);
1241 if !self.propagate_event {
1242 break;
1243 }
1244 }
1245
1246 global_listeners.extend(
1247 self.global_action_listeners
1248 .remove(&action.as_any().type_id())
1249 .unwrap_or_default(),
1250 );
1251
1252 self.global_action_listeners
1253 .insert(action.as_any().type_id(), global_listeners);
1254 }
1255 }
1256 }
1257
1258 /// Is there currently something being dragged?
1259 pub fn has_active_drag(&self) -> bool {
1260 self.active_drag.is_some()
1261 }
1262
1263 /// Set the prompt renderer for GPUI. This will replace the default or platform specific
1264 /// prompts with this custom implementation.
1265 pub fn set_prompt_builder(
1266 &mut self,
1267 renderer: impl Fn(
1268 PromptLevel,
1269 &str,
1270 Option<&str>,
1271 &[&str],
1272 PromptHandle,
1273 &mut WindowContext,
1274 ) -> RenderablePromptHandle
1275 + 'static,
1276 ) {
1277 self.prompt_builder = Some(PromptBuilder::Custom(Box::new(renderer)))
1278 }
1279
1280 /// Remove an asset from GPUI's cache
1281 pub fn remove_cached_asset<A: Asset + 'static>(&mut self, source: &A::Source) {
1282 let asset_id = (TypeId::of::<A>(), hash(source));
1283 self.loading_assets.remove(&asset_id);
1284 }
1285
1286 /// Asynchronously load an asset, if the asset hasn't finished loading this will return None.
1287 ///
1288 /// Note that the multiple calls to this method will only result in one `Asset::load` call at a
1289 /// time, and the results of this call will be cached
1290 ///
1291 /// This asset will not be cached by default, see [Self::use_cached_asset]
1292 pub fn fetch_asset<A: Asset + 'static>(
1293 &mut self,
1294 source: &A::Source,
1295 ) -> (Shared<Task<A::Output>>, bool) {
1296 let asset_id = (TypeId::of::<A>(), hash(source));
1297 let mut is_first = false;
1298 let task = self
1299 .loading_assets
1300 .remove(&asset_id)
1301 .map(|boxed_task| *boxed_task.downcast::<Shared<Task<A::Output>>>().unwrap())
1302 .unwrap_or_else(|| {
1303 is_first = true;
1304 let future = A::load(source.clone(), self);
1305 let task = self.background_executor().spawn(future).shared();
1306 task
1307 });
1308
1309 self.loading_assets.insert(asset_id, Box::new(task.clone()));
1310
1311 (task, is_first)
1312 }
1313
1314 /// Returns the time to first window draw, if available.
1315 pub fn time_to_first_window_draw(&self) -> Option<Duration> {
1316 match self.time_to_first_window_draw {
1317 Some(TimeToFirstWindowDraw::Done(duration)) => Some(duration),
1318 _ => None,
1319 }
1320 }
1321}
1322
1323impl Context for AppContext {
1324 type Result<T> = T;
1325
1326 /// Build an entity that is owned by the application. The given function will be invoked with
1327 /// a `ModelContext` and must return an object representing the entity. A `Model` handle will be returned,
1328 /// which can be used to access the entity in a context.
1329 fn new_model<T: 'static>(
1330 &mut self,
1331 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
1332 ) -> Model<T> {
1333 self.update(|cx| {
1334 let slot = cx.entities.reserve();
1335 let entity = build_model(&mut ModelContext::new(cx, slot.downgrade()));
1336 cx.entities.insert(slot, entity)
1337 })
1338 }
1339
1340 fn reserve_model<T: 'static>(&mut self) -> Self::Result<Reservation<T>> {
1341 Reservation(self.entities.reserve())
1342 }
1343
1344 fn insert_model<T: 'static>(
1345 &mut self,
1346 reservation: Reservation<T>,
1347 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
1348 ) -> Self::Result<Model<T>> {
1349 self.update(|cx| {
1350 let slot = reservation.0;
1351 let entity = build_model(&mut ModelContext::new(cx, slot.downgrade()));
1352 cx.entities.insert(slot, entity)
1353 })
1354 }
1355
1356 /// Updates the entity referenced by the given model. The function is passed a mutable reference to the
1357 /// entity along with a `ModelContext` for the entity.
1358 fn update_model<T: 'static, R>(
1359 &mut self,
1360 model: &Model<T>,
1361 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
1362 ) -> R {
1363 self.update(|cx| {
1364 let mut entity = cx.entities.lease(model);
1365 let result = update(&mut entity, &mut ModelContext::new(cx, model.downgrade()));
1366 cx.entities.end_lease(entity);
1367 result
1368 })
1369 }
1370
1371 fn read_model<T, R>(
1372 &self,
1373 handle: &Model<T>,
1374 read: impl FnOnce(&T, &AppContext) -> R,
1375 ) -> Self::Result<R>
1376 where
1377 T: 'static,
1378 {
1379 let entity = self.entities.read(handle);
1380 read(entity, self)
1381 }
1382
1383 fn update_window<T, F>(&mut self, handle: AnyWindowHandle, update: F) -> Result<T>
1384 where
1385 F: FnOnce(AnyView, &mut WindowContext<'_>) -> T,
1386 {
1387 self.update(|cx| {
1388 let mut window = cx
1389 .windows
1390 .get_mut(handle.id)
1391 .ok_or_else(|| anyhow!("window not found"))?
1392 .take()
1393 .ok_or_else(|| anyhow!("window not found"))?;
1394
1395 let root_view = window.root_view.clone().unwrap();
1396 let result = update(root_view, &mut WindowContext::new(cx, &mut window));
1397
1398 if window.removed {
1399 cx.window_handles.remove(&handle.id);
1400 cx.windows.remove(handle.id);
1401 } else {
1402 cx.windows
1403 .get_mut(handle.id)
1404 .ok_or_else(|| anyhow!("window not found"))?
1405 .replace(window);
1406 }
1407
1408 Ok(result)
1409 })
1410 }
1411
1412 fn read_window<T, R>(
1413 &self,
1414 window: &WindowHandle<T>,
1415 read: impl FnOnce(View<T>, &AppContext) -> R,
1416 ) -> Result<R>
1417 where
1418 T: 'static,
1419 {
1420 let window = self
1421 .windows
1422 .get(window.id)
1423 .ok_or_else(|| anyhow!("window not found"))?
1424 .as_ref()
1425 .unwrap();
1426
1427 let root_view = window.root_view.clone().unwrap();
1428 let view = root_view
1429 .downcast::<T>()
1430 .map_err(|_| anyhow!("root view's type has changed"))?;
1431
1432 Ok(read(view, self))
1433 }
1434}
1435
1436/// These effects are processed at the end of each application update cycle.
1437pub(crate) enum Effect {
1438 Notify {
1439 emitter: EntityId,
1440 },
1441 Emit {
1442 emitter: EntityId,
1443 event_type: TypeId,
1444 event: Box<dyn Any>,
1445 },
1446 Refresh,
1447 NotifyGlobalObservers {
1448 global_type: TypeId,
1449 },
1450 Defer {
1451 callback: Box<dyn FnOnce(&mut AppContext) + 'static>,
1452 },
1453}
1454
1455/// Wraps a global variable value during `update_global` while the value has been moved to the stack.
1456pub(crate) struct GlobalLease<G: Global> {
1457 global: Box<dyn Any>,
1458 global_type: PhantomData<G>,
1459}
1460
1461impl<G: Global> GlobalLease<G> {
1462 fn new(global: Box<dyn Any>) -> Self {
1463 GlobalLease {
1464 global,
1465 global_type: PhantomData,
1466 }
1467 }
1468}
1469
1470impl<G: Global> Deref for GlobalLease<G> {
1471 type Target = G;
1472
1473 fn deref(&self) -> &Self::Target {
1474 self.global.downcast_ref().unwrap()
1475 }
1476}
1477
1478impl<G: Global> DerefMut for GlobalLease<G> {
1479 fn deref_mut(&mut self) -> &mut Self::Target {
1480 self.global.downcast_mut().unwrap()
1481 }
1482}
1483
1484/// Represents the initialization duration of the application.
1485#[derive(Clone, Copy)]
1486pub enum TimeToFirstWindowDraw {
1487 /// The application is still initializing, and contains the start time.
1488 Pending(Instant),
1489 /// The application has finished initializing, and contains the total duration.
1490 Done(Duration),
1491}
1492
1493/// Contains state associated with an active drag operation, started by dragging an element
1494/// within the window or by dragging into the app from the underlying platform.
1495pub struct AnyDrag {
1496 /// The view used to render this drag
1497 pub view: AnyView,
1498
1499 /// The value of the dragged item, to be dropped
1500 pub value: Box<dyn Any>,
1501
1502 /// This is used to render the dragged item in the same place
1503 /// on the original element that the drag was initiated
1504 pub cursor_offset: Point<Pixels>,
1505}
1506
1507/// Contains state associated with a tooltip. You'll only need this struct if you're implementing
1508/// tooltip behavior on a custom element. Otherwise, use [Div::tooltip].
1509#[derive(Clone)]
1510pub struct AnyTooltip {
1511 /// The view used to display the tooltip
1512 pub view: AnyView,
1513
1514 /// The absolute position of the mouse when the tooltip was deployed.
1515 pub mouse_position: Point<Pixels>,
1516}
1517
1518/// A keystroke event, and potentially the associated action
1519#[derive(Debug)]
1520pub struct KeystrokeEvent {
1521 /// The keystroke that occurred
1522 pub keystroke: Keystroke,
1523
1524 /// The action that was resolved for the keystroke, if any
1525 pub action: Option<Box<dyn Action>>,
1526}