app.rs

   1use std::{
   2    any::{TypeId, type_name},
   3    cell::{Ref, RefCell, RefMut},
   4    marker::PhantomData,
   5    mem,
   6    ops::{Deref, DerefMut},
   7    path::{Path, PathBuf},
   8    rc::{Rc, Weak},
   9    sync::{Arc, atomic::Ordering::SeqCst},
  10    time::Duration,
  11};
  12
  13use anyhow::{Result, anyhow};
  14use derive_more::{Deref, DerefMut};
  15use futures::{
  16    Future, FutureExt,
  17    channel::oneshot,
  18    future::{LocalBoxFuture, Shared},
  19};
  20use parking_lot::RwLock;
  21use slotmap::SlotMap;
  22
  23pub use async_context::*;
  24use collections::{FxHashMap, FxHashSet, HashMap, VecDeque};
  25pub use context::*;
  26pub use entity_map::*;
  27use http_client::{HttpClient, Url};
  28use smallvec::SmallVec;
  29#[cfg(any(test, feature = "test-support"))]
  30pub use test_context::*;
  31use util::{ResultExt, debug_panic};
  32
  33use crate::{
  34    Action, ActionBuildError, ActionRegistry, Any, AnyView, AnyWindowHandle, AppContext, Asset,
  35    AssetSource, BackgroundExecutor, Bounds, ClipboardItem, CursorStyle, DispatchPhase, DisplayId,
  36    EventEmitter, FocusHandle, FocusMap, ForegroundExecutor, Global, KeyBinding, KeyContext,
  37    Keymap, Keystroke, LayoutId, Menu, MenuItem, OwnedMenu, PathPromptOptions, Pixels, Platform,
  38    PlatformDisplay, PlatformKeyboardLayout, Point, PromptBuilder, PromptHandle, PromptLevel,
  39    Render, RenderImage, RenderablePromptHandle, Reservation, ScreenCaptureSource, SharedString,
  40    SubscriberSet, Subscription, SvgRenderer, Task, TextSystem, Window, WindowAppearance,
  41    WindowHandle, WindowId, WindowInvalidator,
  42    colors::{Colors, GlobalColors},
  43    current_platform, hash, init_app_menus,
  44};
  45
  46mod async_context;
  47mod context;
  48mod entity_map;
  49#[cfg(any(test, feature = "test-support"))]
  50mod test_context;
  51
  52/// The duration for which futures returned from [Context::on_app_quit] can run before the application fully quits.
  53pub const SHUTDOWN_TIMEOUT: Duration = Duration::from_millis(100);
  54
  55/// Temporary(?) wrapper around [`RefCell<App>`] to help us debug any double borrows.
  56/// Strongly consider removing after stabilization.
  57#[doc(hidden)]
  58pub struct AppCell {
  59    app: RefCell<App>,
  60}
  61
  62impl AppCell {
  63    #[doc(hidden)]
  64    #[track_caller]
  65    pub fn borrow(&self) -> AppRef {
  66        if option_env!("TRACK_THREAD_BORROWS").is_some() {
  67            let thread_id = std::thread::current().id();
  68            eprintln!("borrowed {thread_id:?}");
  69        }
  70        AppRef(self.app.borrow())
  71    }
  72
  73    #[doc(hidden)]
  74    #[track_caller]
  75    pub fn borrow_mut(&self) -> AppRefMut {
  76        if option_env!("TRACK_THREAD_BORROWS").is_some() {
  77            let thread_id = std::thread::current().id();
  78            eprintln!("borrowed {thread_id:?}");
  79        }
  80        AppRefMut(self.app.borrow_mut())
  81    }
  82}
  83
  84#[doc(hidden)]
  85#[derive(Deref, DerefMut)]
  86pub struct AppRef<'a>(Ref<'a, App>);
  87
  88impl Drop for AppRef<'_> {
  89    fn drop(&mut self) {
  90        if option_env!("TRACK_THREAD_BORROWS").is_some() {
  91            let thread_id = std::thread::current().id();
  92            eprintln!("dropped borrow from {thread_id:?}");
  93        }
  94    }
  95}
  96
  97#[doc(hidden)]
  98#[derive(Deref, DerefMut)]
  99pub struct AppRefMut<'a>(RefMut<'a, App>);
 100
 101impl Drop for AppRefMut<'_> {
 102    fn drop(&mut self) {
 103        if option_env!("TRACK_THREAD_BORROWS").is_some() {
 104            let thread_id = std::thread::current().id();
 105            eprintln!("dropped {thread_id:?}");
 106        }
 107    }
 108}
 109
 110/// A reference to a GPUI application, typically constructed in the `main` function of your app.
 111/// You won't interact with this type much outside of initial configuration and startup.
 112pub struct Application(Rc<AppCell>);
 113
 114/// Represents an application before it is fully launched. Once your app is
 115/// configured, you'll start the app with `App::run`.
 116impl Application {
 117    /// Builds an app with the given asset source.
 118    #[allow(clippy::new_without_default)]
 119    pub fn new() -> Self {
 120        #[cfg(any(test, feature = "test-support"))]
 121        log::info!("GPUI was compiled in test mode");
 122
 123        Self(App::new_app(
 124            current_platform(false),
 125            Arc::new(()),
 126            Arc::new(NullHttpClient),
 127        ))
 128    }
 129
 130    /// Build an app in headless mode. This prevents opening windows,
 131    /// but makes it possible to run an application in an context like
 132    /// SSH, where GUI applications are not allowed.
 133    pub fn headless() -> Self {
 134        Self(App::new_app(
 135            current_platform(true),
 136            Arc::new(()),
 137            Arc::new(NullHttpClient),
 138        ))
 139    }
 140
 141    /// Assign
 142    pub fn with_assets(self, asset_source: impl AssetSource) -> Self {
 143        let mut context_lock = self.0.borrow_mut();
 144        let asset_source = Arc::new(asset_source);
 145        context_lock.asset_source = asset_source.clone();
 146        context_lock.svg_renderer = SvgRenderer::new(asset_source);
 147        drop(context_lock);
 148        self
 149    }
 150
 151    /// Sets the HTTP client for the application.
 152    pub fn with_http_client(self, http_client: Arc<dyn HttpClient>) -> Self {
 153        let mut context_lock = self.0.borrow_mut();
 154        context_lock.http_client = http_client;
 155        drop(context_lock);
 156        self
 157    }
 158
 159    /// Start the application. The provided callback will be called once the
 160    /// app is fully launched.
 161    pub fn run<F>(self, on_finish_launching: F)
 162    where
 163        F: 'static + FnOnce(&mut App),
 164    {
 165        let this = self.0.clone();
 166        let platform = self.0.borrow().platform.clone();
 167        platform.run(Box::new(move || {
 168            let cx = &mut *this.borrow_mut();
 169            on_finish_launching(cx);
 170        }));
 171    }
 172
 173    /// Register a handler to be invoked when the platform instructs the application
 174    /// to open one or more URLs.
 175    pub fn on_open_urls<F>(&self, mut callback: F) -> &Self
 176    where
 177        F: 'static + FnMut(Vec<String>),
 178    {
 179        self.0.borrow().platform.on_open_urls(Box::new(callback));
 180        self
 181    }
 182
 183    /// Invokes a handler when an already-running application is launched.
 184    /// On macOS, this can occur when the application icon is double-clicked or the app is launched via the dock.
 185    pub fn on_reopen<F>(&self, mut callback: F) -> &Self
 186    where
 187        F: 'static + FnMut(&mut App),
 188    {
 189        let this = Rc::downgrade(&self.0);
 190        self.0.borrow_mut().platform.on_reopen(Box::new(move || {
 191            if let Some(app) = this.upgrade() {
 192                callback(&mut app.borrow_mut());
 193            }
 194        }));
 195        self
 196    }
 197
 198    /// Returns a handle to the [`BackgroundExecutor`] associated with this app, which can be used to spawn futures in the background.
 199    pub fn background_executor(&self) -> BackgroundExecutor {
 200        self.0.borrow().background_executor.clone()
 201    }
 202
 203    /// Returns a handle to the [`ForegroundExecutor`] associated with this app, which can be used to spawn futures in the foreground.
 204    pub fn foreground_executor(&self) -> ForegroundExecutor {
 205        self.0.borrow().foreground_executor.clone()
 206    }
 207
 208    /// Returns a reference to the [`TextSystem`] associated with this app.
 209    pub fn text_system(&self) -> Arc<TextSystem> {
 210        self.0.borrow().text_system.clone()
 211    }
 212
 213    /// Returns the file URL of the executable with the specified name in the application bundle
 214    pub fn path_for_auxiliary_executable(&self, name: &str) -> Result<PathBuf> {
 215        self.0.borrow().path_for_auxiliary_executable(name)
 216    }
 217}
 218
 219type Handler = Box<dyn FnMut(&mut App) -> bool + 'static>;
 220type Listener = Box<dyn FnMut(&dyn Any, &mut App) -> bool + 'static>;
 221pub(crate) type KeystrokeObserver =
 222    Box<dyn FnMut(&KeystrokeEvent, &mut Window, &mut App) -> bool + 'static>;
 223type QuitHandler = Box<dyn FnOnce(&mut App) -> LocalBoxFuture<'static, ()> + 'static>;
 224type WindowClosedHandler = Box<dyn FnMut(&mut App)>;
 225type ReleaseListener = Box<dyn FnOnce(&mut dyn Any, &mut App) + 'static>;
 226type NewEntityListener = Box<dyn FnMut(AnyEntity, &mut Option<&mut Window>, &mut App) + 'static>;
 227
 228/// Contains the state of the full application, and passed as a reference to a variety of callbacks.
 229/// Other [Context] derefs to this type.
 230/// You need a reference to an `App` to access the state of a [Entity].
 231pub struct App {
 232    pub(crate) this: Weak<AppCell>,
 233    pub(crate) platform: Rc<dyn Platform>,
 234    text_system: Arc<TextSystem>,
 235    flushing_effects: bool,
 236    pending_updates: usize,
 237    pub(crate) actions: Rc<ActionRegistry>,
 238    pub(crate) active_drag: Option<AnyDrag>,
 239    pub(crate) background_executor: BackgroundExecutor,
 240    pub(crate) foreground_executor: ForegroundExecutor,
 241    pub(crate) loading_assets: FxHashMap<(TypeId, u64), Box<dyn Any>>,
 242    asset_source: Arc<dyn AssetSource>,
 243    pub(crate) svg_renderer: SvgRenderer,
 244    http_client: Arc<dyn HttpClient>,
 245    pub(crate) globals_by_type: FxHashMap<TypeId, Box<dyn Any>>,
 246    pub(crate) entities: EntityMap,
 247    pub(crate) window_update_stack: Vec<WindowId>,
 248    pub(crate) new_entity_observers: SubscriberSet<TypeId, NewEntityListener>,
 249    pub(crate) windows: SlotMap<WindowId, Option<Window>>,
 250    pub(crate) window_handles: FxHashMap<WindowId, AnyWindowHandle>,
 251    pub(crate) focus_handles: Arc<FocusMap>,
 252    pub(crate) keymap: Rc<RefCell<Keymap>>,
 253    pub(crate) keyboard_layout: Box<dyn PlatformKeyboardLayout>,
 254    pub(crate) global_action_listeners:
 255        FxHashMap<TypeId, Vec<Rc<dyn Fn(&dyn Any, DispatchPhase, &mut Self)>>>,
 256    pending_effects: VecDeque<Effect>,
 257    pub(crate) pending_notifications: FxHashSet<EntityId>,
 258    pub(crate) pending_global_notifications: FxHashSet<TypeId>,
 259    pub(crate) observers: SubscriberSet<EntityId, Handler>,
 260    // TypeId is the type of the event that the listener callback expects
 261    pub(crate) event_listeners: SubscriberSet<EntityId, (TypeId, Listener)>,
 262    pub(crate) keystroke_observers: SubscriberSet<(), KeystrokeObserver>,
 263    pub(crate) keyboard_layout_observers: SubscriberSet<(), Handler>,
 264    pub(crate) release_listeners: SubscriberSet<EntityId, ReleaseListener>,
 265    pub(crate) global_observers: SubscriberSet<TypeId, Handler>,
 266    pub(crate) quit_observers: SubscriberSet<(), QuitHandler>,
 267    pub(crate) window_closed_observers: SubscriberSet<(), WindowClosedHandler>,
 268    pub(crate) layout_id_buffer: Vec<LayoutId>, // We recycle this memory across layout requests.
 269    pub(crate) propagate_event: bool,
 270    pub(crate) prompt_builder: Option<PromptBuilder>,
 271    pub(crate) window_invalidators_by_entity:
 272        FxHashMap<EntityId, FxHashMap<WindowId, WindowInvalidator>>,
 273    pub(crate) tracked_entities: FxHashMap<WindowId, FxHashSet<EntityId>>,
 274    #[cfg(any(test, feature = "test-support", debug_assertions))]
 275    pub(crate) name: Option<&'static str>,
 276    quitting: bool,
 277}
 278
 279impl App {
 280    #[allow(clippy::new_ret_no_self)]
 281    pub(crate) fn new_app(
 282        platform: Rc<dyn Platform>,
 283        asset_source: Arc<dyn AssetSource>,
 284        http_client: Arc<dyn HttpClient>,
 285    ) -> Rc<AppCell> {
 286        let executor = platform.background_executor();
 287        let foreground_executor = platform.foreground_executor();
 288        assert!(
 289            executor.is_main_thread(),
 290            "must construct App on main thread"
 291        );
 292
 293        let text_system = Arc::new(TextSystem::new(platform.text_system()));
 294        let entities = EntityMap::new();
 295        let keyboard_layout = platform.keyboard_layout();
 296
 297        let app = Rc::new_cyclic(|this| AppCell {
 298            app: RefCell::new(App {
 299                this: this.clone(),
 300                platform: platform.clone(),
 301                text_system,
 302                actions: Rc::new(ActionRegistry::default()),
 303                flushing_effects: false,
 304                pending_updates: 0,
 305                active_drag: None,
 306                background_executor: executor,
 307                foreground_executor,
 308                svg_renderer: SvgRenderer::new(asset_source.clone()),
 309                loading_assets: Default::default(),
 310                asset_source,
 311                http_client,
 312                globals_by_type: FxHashMap::default(),
 313                entities,
 314                new_entity_observers: SubscriberSet::new(),
 315                windows: SlotMap::with_key(),
 316                window_update_stack: Vec::new(),
 317                window_handles: FxHashMap::default(),
 318                focus_handles: Arc::new(RwLock::new(SlotMap::with_key())),
 319                keymap: Rc::new(RefCell::new(Keymap::default())),
 320                keyboard_layout,
 321                global_action_listeners: FxHashMap::default(),
 322                pending_effects: VecDeque::new(),
 323                pending_notifications: FxHashSet::default(),
 324                pending_global_notifications: FxHashSet::default(),
 325                observers: SubscriberSet::new(),
 326                tracked_entities: FxHashMap::default(),
 327                window_invalidators_by_entity: FxHashMap::default(),
 328                event_listeners: SubscriberSet::new(),
 329                release_listeners: SubscriberSet::new(),
 330                keystroke_observers: SubscriberSet::new(),
 331                keyboard_layout_observers: SubscriberSet::new(),
 332                global_observers: SubscriberSet::new(),
 333                quit_observers: SubscriberSet::new(),
 334                window_closed_observers: SubscriberSet::new(),
 335                layout_id_buffer: Default::default(),
 336                propagate_event: true,
 337                prompt_builder: Some(PromptBuilder::Default),
 338                quitting: false,
 339
 340                #[cfg(any(test, feature = "test-support", debug_assertions))]
 341                name: None,
 342            }),
 343        });
 344
 345        init_app_menus(platform.as_ref(), &mut app.borrow_mut());
 346
 347        platform.on_keyboard_layout_change(Box::new({
 348            let app = Rc::downgrade(&app);
 349            move || {
 350                if let Some(app) = app.upgrade() {
 351                    let cx = &mut app.borrow_mut();
 352                    cx.keyboard_layout = cx.platform.keyboard_layout();
 353                    cx.keyboard_layout_observers
 354                        .clone()
 355                        .retain(&(), move |callback| (callback)(cx));
 356                }
 357            }
 358        }));
 359
 360        platform.on_quit(Box::new({
 361            let cx = app.clone();
 362            move || {
 363                cx.borrow_mut().shutdown();
 364            }
 365        }));
 366
 367        app
 368    }
 369
 370    /// Quit the application gracefully. Handlers registered with [`Context::on_app_quit`]
 371    /// will be given 100ms to complete before exiting.
 372    pub fn shutdown(&mut self) {
 373        let mut futures = Vec::new();
 374
 375        for observer in self.quit_observers.remove(&()) {
 376            futures.push(observer(self));
 377        }
 378
 379        self.windows.clear();
 380        self.window_handles.clear();
 381        self.flush_effects();
 382        self.quitting = true;
 383
 384        let futures = futures::future::join_all(futures);
 385        if self
 386            .background_executor
 387            .block_with_timeout(SHUTDOWN_TIMEOUT, futures)
 388            .is_err()
 389        {
 390            log::error!("timed out waiting on app_will_quit");
 391        }
 392
 393        self.quitting = false;
 394    }
 395
 396    /// Get the id of the current keyboard layout
 397    pub fn keyboard_layout(&self) -> &dyn PlatformKeyboardLayout {
 398        self.keyboard_layout.as_ref()
 399    }
 400
 401    /// Invokes a handler when the current keyboard layout changes
 402    pub fn on_keyboard_layout_change<F>(&self, mut callback: F) -> Subscription
 403    where
 404        F: 'static + FnMut(&mut App),
 405    {
 406        let (subscription, activate) = self.keyboard_layout_observers.insert(
 407            (),
 408            Box::new(move |cx| {
 409                callback(cx);
 410                true
 411            }),
 412        );
 413        activate();
 414        subscription
 415    }
 416
 417    /// Gracefully quit the application via the platform's standard routine.
 418    pub fn quit(&self) {
 419        self.platform.quit();
 420    }
 421
 422    /// Schedules all windows in the application to be redrawn. This can be called
 423    /// multiple times in an update cycle and still result in a single redraw.
 424    pub fn refresh_windows(&mut self) {
 425        self.pending_effects.push_back(Effect::RefreshWindows);
 426    }
 427
 428    pub(crate) fn update<R>(&mut self, update: impl FnOnce(&mut Self) -> R) -> R {
 429        self.pending_updates += 1;
 430        let result = update(self);
 431        if !self.flushing_effects && self.pending_updates == 1 {
 432            self.flushing_effects = true;
 433            self.flush_effects();
 434            self.flushing_effects = false;
 435        }
 436        self.pending_updates -= 1;
 437        result
 438    }
 439
 440    /// Arrange a callback to be invoked when the given entity calls `notify` on its respective context.
 441    pub fn observe<W>(
 442        &mut self,
 443        entity: &Entity<W>,
 444        mut on_notify: impl FnMut(Entity<W>, &mut App) + 'static,
 445    ) -> Subscription
 446    where
 447        W: 'static,
 448    {
 449        self.observe_internal(entity, move |e, cx| {
 450            on_notify(e, cx);
 451            true
 452        })
 453    }
 454
 455    pub(crate) fn detect_accessed_entities<R>(
 456        &mut self,
 457        callback: impl FnOnce(&mut App) -> R,
 458    ) -> (R, FxHashSet<EntityId>) {
 459        let accessed_entities_start = self.entities.accessed_entities.borrow().clone();
 460        let result = callback(self);
 461        let accessed_entities_end = self.entities.accessed_entities.borrow().clone();
 462        let entities_accessed_in_callback = accessed_entities_end
 463            .difference(&accessed_entities_start)
 464            .copied()
 465            .collect::<FxHashSet<EntityId>>();
 466        (result, entities_accessed_in_callback)
 467    }
 468
 469    pub(crate) fn record_entities_accessed(
 470        &mut self,
 471        window_handle: AnyWindowHandle,
 472        invalidator: WindowInvalidator,
 473        entities: &FxHashSet<EntityId>,
 474    ) {
 475        let mut tracked_entities =
 476            std::mem::take(self.tracked_entities.entry(window_handle.id).or_default());
 477        for entity in tracked_entities.iter() {
 478            self.window_invalidators_by_entity
 479                .entry(*entity)
 480                .and_modify(|windows| {
 481                    windows.remove(&window_handle.id);
 482                });
 483        }
 484        for entity in entities.iter() {
 485            self.window_invalidators_by_entity
 486                .entry(*entity)
 487                .or_default()
 488                .insert(window_handle.id, invalidator.clone());
 489        }
 490        tracked_entities.clear();
 491        tracked_entities.extend(entities.iter().copied());
 492        self.tracked_entities
 493            .insert(window_handle.id, tracked_entities);
 494    }
 495
 496    pub(crate) fn new_observer(&mut self, key: EntityId, value: Handler) -> Subscription {
 497        let (subscription, activate) = self.observers.insert(key, value);
 498        self.defer(move |_| activate());
 499        subscription
 500    }
 501
 502    pub(crate) fn observe_internal<W>(
 503        &mut self,
 504        entity: &Entity<W>,
 505        mut on_notify: impl FnMut(Entity<W>, &mut App) -> bool + 'static,
 506    ) -> Subscription
 507    where
 508        W: 'static,
 509    {
 510        let entity_id = entity.entity_id();
 511        let handle = entity.downgrade();
 512        self.new_observer(
 513            entity_id,
 514            Box::new(move |cx| {
 515                if let Some(entity) = handle.upgrade() {
 516                    on_notify(entity, cx)
 517                } else {
 518                    false
 519                }
 520            }),
 521        )
 522    }
 523
 524    /// Arrange for the given callback to be invoked whenever the given entity emits an event of a given type.
 525    /// The callback is provided a handle to the emitting entity and a reference to the emitted event.
 526    pub fn subscribe<T, Event>(
 527        &mut self,
 528        entity: &Entity<T>,
 529        mut on_event: impl FnMut(Entity<T>, &Event, &mut App) + 'static,
 530    ) -> Subscription
 531    where
 532        T: 'static + EventEmitter<Event>,
 533        Event: 'static,
 534    {
 535        self.subscribe_internal(entity, move |entity, event, cx| {
 536            on_event(entity, event, cx);
 537            true
 538        })
 539    }
 540
 541    pub(crate) fn new_subscription(
 542        &mut self,
 543        key: EntityId,
 544        value: (TypeId, Listener),
 545    ) -> Subscription {
 546        let (subscription, activate) = self.event_listeners.insert(key, value);
 547        self.defer(move |_| activate());
 548        subscription
 549    }
 550    pub(crate) fn subscribe_internal<T, Evt>(
 551        &mut self,
 552        entity: &Entity<T>,
 553        mut on_event: impl FnMut(Entity<T>, &Evt, &mut App) -> bool + 'static,
 554    ) -> Subscription
 555    where
 556        T: 'static + EventEmitter<Evt>,
 557        Evt: 'static,
 558    {
 559        let entity_id = entity.entity_id();
 560        let handle = entity.downgrade();
 561        self.new_subscription(
 562            entity_id,
 563            (
 564                TypeId::of::<Evt>(),
 565                Box::new(move |event, cx| {
 566                    let event: &Evt = event.downcast_ref().expect("invalid event type");
 567                    if let Some(entity) = handle.upgrade() {
 568                        on_event(entity, event, cx)
 569                    } else {
 570                        false
 571                    }
 572                }),
 573            ),
 574        )
 575    }
 576
 577    /// Returns handles to all open windows in the application.
 578    /// Each handle could be downcast to a handle typed for the root view of that window.
 579    /// To find all windows of a given type, you could filter on
 580    pub fn windows(&self) -> Vec<AnyWindowHandle> {
 581        self.windows
 582            .keys()
 583            .flat_map(|window_id| self.window_handles.get(&window_id).copied())
 584            .collect()
 585    }
 586
 587    /// Returns the window handles ordered by their appearance on screen, front to back.
 588    ///
 589    /// The first window in the returned list is the active/topmost window of the application.
 590    ///
 591    /// This method returns None if the platform doesn't implement the method yet.
 592    pub fn window_stack(&self) -> Option<Vec<AnyWindowHandle>> {
 593        self.platform.window_stack()
 594    }
 595
 596    /// Returns a handle to the window that is currently focused at the platform level, if one exists.
 597    pub fn active_window(&self) -> Option<AnyWindowHandle> {
 598        self.platform.active_window()
 599    }
 600
 601    /// Opens a new window with the given option and the root view returned by the given function.
 602    /// The function is invoked with a `Window`, which can be used to interact with window-specific
 603    /// functionality.
 604    pub fn open_window<V: 'static + Render>(
 605        &mut self,
 606        options: crate::WindowOptions,
 607        build_root_view: impl FnOnce(&mut Window, &mut App) -> Entity<V>,
 608    ) -> anyhow::Result<WindowHandle<V>> {
 609        self.update(|cx| {
 610            let id = cx.windows.insert(None);
 611            let handle = WindowHandle::new(id);
 612            match Window::new(handle.into(), options, cx) {
 613                Ok(mut window) => {
 614                    cx.window_update_stack.push(id);
 615                    let root_view = build_root_view(&mut window, cx);
 616                    cx.window_update_stack.pop();
 617                    window.root.replace(root_view.into());
 618                    window.defer(cx, |window: &mut Window, cx| window.appearance_changed(cx));
 619                    cx.window_handles.insert(id, window.handle);
 620                    cx.windows.get_mut(id).unwrap().replace(window);
 621                    Ok(handle)
 622                }
 623                Err(e) => {
 624                    cx.windows.remove(id);
 625                    Err(e)
 626                }
 627            }
 628        })
 629    }
 630
 631    /// Instructs the platform to activate the application by bringing it to the foreground.
 632    pub fn activate(&self, ignoring_other_apps: bool) {
 633        self.platform.activate(ignoring_other_apps);
 634    }
 635
 636    /// Hide the application at the platform level.
 637    pub fn hide(&self) {
 638        self.platform.hide();
 639    }
 640
 641    /// Hide other applications at the platform level.
 642    pub fn hide_other_apps(&self) {
 643        self.platform.hide_other_apps();
 644    }
 645
 646    /// Unhide other applications at the platform level.
 647    pub fn unhide_other_apps(&self) {
 648        self.platform.unhide_other_apps();
 649    }
 650
 651    /// Returns the list of currently active displays.
 652    pub fn displays(&self) -> Vec<Rc<dyn PlatformDisplay>> {
 653        self.platform.displays()
 654    }
 655
 656    /// Returns the primary display that will be used for new windows.
 657    pub fn primary_display(&self) -> Option<Rc<dyn PlatformDisplay>> {
 658        self.platform.primary_display()
 659    }
 660
 661    /// Returns whether `screen_capture_sources` may work.
 662    pub fn is_screen_capture_supported(&self) -> bool {
 663        self.platform.is_screen_capture_supported()
 664    }
 665
 666    /// Returns a list of available screen capture sources.
 667    pub fn screen_capture_sources(
 668        &self,
 669    ) -> oneshot::Receiver<Result<Vec<Box<dyn ScreenCaptureSource>>>> {
 670        self.platform.screen_capture_sources()
 671    }
 672
 673    /// Returns the display with the given ID, if one exists.
 674    pub fn find_display(&self, id: DisplayId) -> Option<Rc<dyn PlatformDisplay>> {
 675        self.displays()
 676            .iter()
 677            .find(|display| display.id() == id)
 678            .cloned()
 679    }
 680
 681    /// Returns the appearance of the application's windows.
 682    pub fn window_appearance(&self) -> WindowAppearance {
 683        self.platform.window_appearance()
 684    }
 685
 686    /// Writes data to the primary selection buffer.
 687    /// Only available on Linux.
 688    #[cfg(any(target_os = "linux", target_os = "freebsd"))]
 689    pub fn write_to_primary(&self, item: ClipboardItem) {
 690        self.platform.write_to_primary(item)
 691    }
 692
 693    /// Writes data to the platform clipboard.
 694    pub fn write_to_clipboard(&self, item: ClipboardItem) {
 695        self.platform.write_to_clipboard(item)
 696    }
 697
 698    /// Reads data from the primary selection buffer.
 699    /// Only available on Linux.
 700    #[cfg(any(target_os = "linux", target_os = "freebsd"))]
 701    pub fn read_from_primary(&self) -> Option<ClipboardItem> {
 702        self.platform.read_from_primary()
 703    }
 704
 705    /// Reads data from the platform clipboard.
 706    pub fn read_from_clipboard(&self) -> Option<ClipboardItem> {
 707        self.platform.read_from_clipboard()
 708    }
 709
 710    /// Writes credentials to the platform keychain.
 711    pub fn write_credentials(
 712        &self,
 713        url: &str,
 714        username: &str,
 715        password: &[u8],
 716    ) -> Task<Result<()>> {
 717        self.platform.write_credentials(url, username, password)
 718    }
 719
 720    /// Reads credentials from the platform keychain.
 721    pub fn read_credentials(&self, url: &str) -> Task<Result<Option<(String, Vec<u8>)>>> {
 722        self.platform.read_credentials(url)
 723    }
 724
 725    /// Deletes credentials from the platform keychain.
 726    pub fn delete_credentials(&self, url: &str) -> Task<Result<()>> {
 727        self.platform.delete_credentials(url)
 728    }
 729
 730    /// Directs the platform's default browser to open the given URL.
 731    pub fn open_url(&self, url: &str) {
 732        self.platform.open_url(url);
 733    }
 734
 735    /// Registers the given URL scheme (e.g. `zed` for `zed://` urls) to be
 736    /// opened by the current app.
 737    ///
 738    /// On some platforms (e.g. macOS) you may be able to register URL schemes
 739    /// as part of app distribution, but this method exists to let you register
 740    /// schemes at runtime.
 741    pub fn register_url_scheme(&self, scheme: &str) -> Task<Result<()>> {
 742        self.platform.register_url_scheme(scheme)
 743    }
 744
 745    /// Returns the full pathname of the current app bundle.
 746    ///
 747    /// Returns an error if the app is not being run from a bundle.
 748    pub fn app_path(&self) -> Result<PathBuf> {
 749        self.platform.app_path()
 750    }
 751
 752    /// On Linux, returns the name of the compositor in use.
 753    ///
 754    /// Returns an empty string on other platforms.
 755    pub fn compositor_name(&self) -> &'static str {
 756        self.platform.compositor_name()
 757    }
 758
 759    /// Returns the file URL of the executable with the specified name in the application bundle
 760    pub fn path_for_auxiliary_executable(&self, name: &str) -> Result<PathBuf> {
 761        self.platform.path_for_auxiliary_executable(name)
 762    }
 763
 764    /// Displays a platform modal for selecting paths.
 765    ///
 766    /// When one or more paths are selected, they'll be relayed asynchronously via the returned oneshot channel.
 767    /// If cancelled, a `None` will be relayed instead.
 768    /// May return an error on Linux if the file picker couldn't be opened.
 769    pub fn prompt_for_paths(
 770        &self,
 771        options: PathPromptOptions,
 772    ) -> oneshot::Receiver<Result<Option<Vec<PathBuf>>>> {
 773        self.platform.prompt_for_paths(options)
 774    }
 775
 776    /// Displays a platform modal for selecting a new path where a file can be saved.
 777    ///
 778    /// The provided directory will be used to set the initial location.
 779    /// When a path is selected, it is relayed asynchronously via the returned oneshot channel.
 780    /// If cancelled, a `None` will be relayed instead.
 781    /// May return an error on Linux if the file picker couldn't be opened.
 782    pub fn prompt_for_new_path(
 783        &self,
 784        directory: &Path,
 785    ) -> oneshot::Receiver<Result<Option<PathBuf>>> {
 786        self.platform.prompt_for_new_path(directory)
 787    }
 788
 789    /// Reveals the specified path at the platform level, such as in Finder on macOS.
 790    pub fn reveal_path(&self, path: &Path) {
 791        self.platform.reveal_path(path)
 792    }
 793
 794    /// Opens the specified path with the system's default application.
 795    pub fn open_with_system(&self, path: &Path) {
 796        self.platform.open_with_system(path)
 797    }
 798
 799    /// Returns whether the user has configured scrollbars to auto-hide at the platform level.
 800    pub fn should_auto_hide_scrollbars(&self) -> bool {
 801        self.platform.should_auto_hide_scrollbars()
 802    }
 803
 804    /// Restarts the application.
 805    pub fn restart(&self, binary_path: Option<PathBuf>) {
 806        self.platform.restart(binary_path)
 807    }
 808
 809    /// Returns the HTTP client for the application.
 810    pub fn http_client(&self) -> Arc<dyn HttpClient> {
 811        self.http_client.clone()
 812    }
 813
 814    /// Sets the HTTP client for the application.
 815    pub fn set_http_client(&mut self, new_client: Arc<dyn HttpClient>) {
 816        self.http_client = new_client;
 817    }
 818
 819    /// Returns the SVG renderer used by the application.
 820    pub fn svg_renderer(&self) -> SvgRenderer {
 821        self.svg_renderer.clone()
 822    }
 823
 824    pub(crate) fn push_effect(&mut self, effect: Effect) {
 825        match &effect {
 826            Effect::Notify { emitter } => {
 827                if !self.pending_notifications.insert(*emitter) {
 828                    return;
 829                }
 830            }
 831            Effect::NotifyGlobalObservers { global_type } => {
 832                if !self.pending_global_notifications.insert(*global_type) {
 833                    return;
 834                }
 835            }
 836            _ => {}
 837        };
 838
 839        self.pending_effects.push_back(effect);
 840    }
 841
 842    /// Called at the end of [`App::update`] to complete any side effects
 843    /// such as notifying observers, emitting events, etc. Effects can themselves
 844    /// cause effects, so we continue looping until all effects are processed.
 845    fn flush_effects(&mut self) {
 846        loop {
 847            self.release_dropped_entities();
 848            self.release_dropped_focus_handles();
 849
 850            if let Some(effect) = self.pending_effects.pop_front() {
 851                match effect {
 852                    Effect::Notify { emitter } => {
 853                        self.apply_notify_effect(emitter);
 854                    }
 855
 856                    Effect::Emit {
 857                        emitter,
 858                        event_type,
 859                        event,
 860                    } => self.apply_emit_effect(emitter, event_type, event),
 861
 862                    Effect::RefreshWindows => {
 863                        self.apply_refresh_effect();
 864                    }
 865
 866                    Effect::NotifyGlobalObservers { global_type } => {
 867                        self.apply_notify_global_observers_effect(global_type);
 868                    }
 869
 870                    Effect::Defer { callback } => {
 871                        self.apply_defer_effect(callback);
 872                    }
 873                    Effect::EntityCreated {
 874                        entity,
 875                        tid,
 876                        window,
 877                    } => {
 878                        self.apply_entity_created_effect(entity, tid, window);
 879                    }
 880                }
 881            } else {
 882                #[cfg(any(test, feature = "test-support"))]
 883                for window in self
 884                    .windows
 885                    .values()
 886                    .filter_map(|window| {
 887                        let window = window.as_ref()?;
 888                        window.invalidator.is_dirty().then_some(window.handle)
 889                    })
 890                    .collect::<Vec<_>>()
 891                {
 892                    self.update_window(window, |_, window, cx| window.draw(cx))
 893                        .unwrap();
 894                }
 895
 896                if self.pending_effects.is_empty() {
 897                    break;
 898                }
 899            }
 900        }
 901    }
 902
 903    /// Repeatedly called during `flush_effects` to release any entities whose
 904    /// reference count has become zero. We invoke any release observers before dropping
 905    /// each entity.
 906    fn release_dropped_entities(&mut self) {
 907        loop {
 908            let dropped = self.entities.take_dropped();
 909            if dropped.is_empty() {
 910                break;
 911            }
 912
 913            for (entity_id, mut entity) in dropped {
 914                self.observers.remove(&entity_id);
 915                self.event_listeners.remove(&entity_id);
 916                for release_callback in self.release_listeners.remove(&entity_id) {
 917                    release_callback(entity.as_mut(), self);
 918                }
 919            }
 920        }
 921    }
 922
 923    /// Repeatedly called during `flush_effects` to handle a focused handle being dropped.
 924    fn release_dropped_focus_handles(&mut self) {
 925        self.focus_handles
 926            .clone()
 927            .write()
 928            .retain(|handle_id, count| {
 929                if count.load(SeqCst) == 0 {
 930                    for window_handle in self.windows() {
 931                        window_handle
 932                            .update(self, |_, window, _| {
 933                                if window.focus == Some(handle_id) {
 934                                    window.blur();
 935                                }
 936                            })
 937                            .unwrap();
 938                    }
 939                    false
 940                } else {
 941                    true
 942                }
 943            });
 944    }
 945
 946    fn apply_notify_effect(&mut self, emitter: EntityId) {
 947        self.pending_notifications.remove(&emitter);
 948
 949        self.observers
 950            .clone()
 951            .retain(&emitter, |handler| handler(self));
 952    }
 953
 954    fn apply_emit_effect(&mut self, emitter: EntityId, event_type: TypeId, event: Box<dyn Any>) {
 955        self.event_listeners
 956            .clone()
 957            .retain(&emitter, |(stored_type, handler)| {
 958                if *stored_type == event_type {
 959                    handler(event.as_ref(), self)
 960                } else {
 961                    true
 962                }
 963            });
 964    }
 965
 966    fn apply_refresh_effect(&mut self) {
 967        for window in self.windows.values_mut() {
 968            if let Some(window) = window.as_mut() {
 969                window.refreshing = true;
 970                window.invalidator.set_dirty(true);
 971            }
 972        }
 973    }
 974
 975    fn apply_notify_global_observers_effect(&mut self, type_id: TypeId) {
 976        self.pending_global_notifications.remove(&type_id);
 977        self.global_observers
 978            .clone()
 979            .retain(&type_id, |observer| observer(self));
 980    }
 981
 982    fn apply_defer_effect(&mut self, callback: Box<dyn FnOnce(&mut Self) + 'static>) {
 983        callback(self);
 984    }
 985
 986    fn apply_entity_created_effect(
 987        &mut self,
 988        entity: AnyEntity,
 989        tid: TypeId,
 990        window: Option<WindowId>,
 991    ) {
 992        self.new_entity_observers.clone().retain(&tid, |observer| {
 993            if let Some(id) = window {
 994                self.update_window_id(id, {
 995                    let entity = entity.clone();
 996                    |_, window, cx| (observer)(entity, &mut Some(window), cx)
 997                })
 998                .expect("All windows should be off the stack when flushing effects");
 999            } else {
1000                (observer)(entity.clone(), &mut None, self)
1001            }
1002            true
1003        });
1004    }
1005
1006    fn update_window_id<T, F>(&mut self, id: WindowId, update: F) -> Result<T>
1007    where
1008        F: FnOnce(AnyView, &mut Window, &mut App) -> T,
1009    {
1010        self.update(|cx| {
1011            let mut window = cx
1012                .windows
1013                .get_mut(id)
1014                .ok_or_else(|| anyhow!("window not found"))?
1015                .take()
1016                .ok_or_else(|| anyhow!("window not found"))?;
1017
1018            let root_view = window.root.clone().unwrap();
1019
1020            cx.window_update_stack.push(window.handle.id);
1021            let result = update(root_view, &mut window, cx);
1022            cx.window_update_stack.pop();
1023
1024            if window.removed {
1025                cx.window_handles.remove(&id);
1026                cx.windows.remove(id);
1027
1028                cx.window_closed_observers.clone().retain(&(), |callback| {
1029                    callback(cx);
1030                    true
1031                });
1032            } else {
1033                cx.windows
1034                    .get_mut(id)
1035                    .ok_or_else(|| anyhow!("window not found"))?
1036                    .replace(window);
1037            }
1038
1039            Ok(result)
1040        })
1041    }
1042    /// Creates an `AsyncApp`, which can be cloned and has a static lifetime
1043    /// so it can be held across `await` points.
1044    pub fn to_async(&self) -> AsyncApp {
1045        AsyncApp {
1046            app: self.this.clone(),
1047            background_executor: self.background_executor.clone(),
1048            foreground_executor: self.foreground_executor.clone(),
1049        }
1050    }
1051
1052    /// Obtains a reference to the executor, which can be used to spawn futures.
1053    pub fn background_executor(&self) -> &BackgroundExecutor {
1054        &self.background_executor
1055    }
1056
1057    /// Obtains a reference to the executor, which can be used to spawn futures.
1058    pub fn foreground_executor(&self) -> &ForegroundExecutor {
1059        if self.quitting {
1060            panic!("Can't spawn on main thread after on_app_quit")
1061        };
1062        &self.foreground_executor
1063    }
1064
1065    /// Spawns the future returned by the given function on the main thread. The closure will be invoked
1066    /// with [AsyncApp], which allows the application state to be accessed across await points.
1067    #[track_caller]
1068    pub fn spawn<AsyncFn, R>(&self, f: AsyncFn) -> Task<R>
1069    where
1070        AsyncFn: AsyncFnOnce(&mut AsyncApp) -> R + 'static,
1071        R: 'static,
1072    {
1073        if self.quitting {
1074            debug_panic!("Can't spawn on main thread after on_app_quit")
1075        };
1076
1077        let mut cx = self.to_async();
1078
1079        self.foreground_executor
1080            .spawn(async move { f(&mut cx).await })
1081    }
1082
1083    /// Schedules the given function to be run at the end of the current effect cycle, allowing entities
1084    /// that are currently on the stack to be returned to the app.
1085    pub fn defer(&mut self, f: impl FnOnce(&mut App) + 'static) {
1086        self.push_effect(Effect::Defer {
1087            callback: Box::new(f),
1088        });
1089    }
1090
1091    /// Accessor for the application's asset source, which is provided when constructing the `App`.
1092    pub fn asset_source(&self) -> &Arc<dyn AssetSource> {
1093        &self.asset_source
1094    }
1095
1096    /// Accessor for the text system.
1097    pub fn text_system(&self) -> &Arc<TextSystem> {
1098        &self.text_system
1099    }
1100
1101    /// Check whether a global of the given type has been assigned.
1102    pub fn has_global<G: Global>(&self) -> bool {
1103        self.globals_by_type.contains_key(&TypeId::of::<G>())
1104    }
1105
1106    /// Access the global of the given type. Panics if a global for that type has not been assigned.
1107    #[track_caller]
1108    pub fn global<G: Global>(&self) -> &G {
1109        self.globals_by_type
1110            .get(&TypeId::of::<G>())
1111            .map(|any_state| any_state.downcast_ref::<G>().unwrap())
1112            .ok_or_else(|| anyhow!("no state of type {} exists", type_name::<G>()))
1113            .unwrap()
1114    }
1115
1116    /// Access the global of the given type if a value has been assigned.
1117    pub fn try_global<G: Global>(&self) -> Option<&G> {
1118        self.globals_by_type
1119            .get(&TypeId::of::<G>())
1120            .map(|any_state| any_state.downcast_ref::<G>().unwrap())
1121    }
1122
1123    /// Access the global of the given type mutably. Panics if a global for that type has not been assigned.
1124    #[track_caller]
1125    pub fn global_mut<G: Global>(&mut self) -> &mut G {
1126        let global_type = TypeId::of::<G>();
1127        self.push_effect(Effect::NotifyGlobalObservers { global_type });
1128        self.globals_by_type
1129            .get_mut(&global_type)
1130            .and_then(|any_state| any_state.downcast_mut::<G>())
1131            .ok_or_else(|| anyhow!("no state of type {} exists", type_name::<G>()))
1132            .unwrap()
1133    }
1134
1135    /// Access the global of the given type mutably. A default value is assigned if a global of this type has not
1136    /// yet been assigned.
1137    pub fn default_global<G: Global + Default>(&mut self) -> &mut G {
1138        let global_type = TypeId::of::<G>();
1139        self.push_effect(Effect::NotifyGlobalObservers { global_type });
1140        self.globals_by_type
1141            .entry(global_type)
1142            .or_insert_with(|| Box::<G>::default())
1143            .downcast_mut::<G>()
1144            .unwrap()
1145    }
1146
1147    /// Sets the value of the global of the given type.
1148    pub fn set_global<G: Global>(&mut self, global: G) {
1149        let global_type = TypeId::of::<G>();
1150        self.push_effect(Effect::NotifyGlobalObservers { global_type });
1151        self.globals_by_type.insert(global_type, Box::new(global));
1152    }
1153
1154    /// Clear all stored globals. Does not notify global observers.
1155    #[cfg(any(test, feature = "test-support"))]
1156    pub fn clear_globals(&mut self) {
1157        self.globals_by_type.drain();
1158    }
1159
1160    /// Remove the global of the given type from the app context. Does not notify global observers.
1161    pub fn remove_global<G: Global>(&mut self) -> G {
1162        let global_type = TypeId::of::<G>();
1163        self.push_effect(Effect::NotifyGlobalObservers { global_type });
1164        *self
1165            .globals_by_type
1166            .remove(&global_type)
1167            .unwrap_or_else(|| panic!("no global added for {}", std::any::type_name::<G>()))
1168            .downcast()
1169            .unwrap()
1170    }
1171
1172    /// Register a callback to be invoked when a global of the given type is updated.
1173    pub fn observe_global<G: Global>(
1174        &mut self,
1175        mut f: impl FnMut(&mut Self) + 'static,
1176    ) -> Subscription {
1177        let (subscription, activate) = self.global_observers.insert(
1178            TypeId::of::<G>(),
1179            Box::new(move |cx| {
1180                f(cx);
1181                true
1182            }),
1183        );
1184        self.defer(move |_| activate());
1185        subscription
1186    }
1187
1188    /// Move the global of the given type to the stack.
1189    #[track_caller]
1190    pub(crate) fn lease_global<G: Global>(&mut self) -> GlobalLease<G> {
1191        GlobalLease::new(
1192            self.globals_by_type
1193                .remove(&TypeId::of::<G>())
1194                .ok_or_else(|| anyhow!("no global registered of type {}", type_name::<G>()))
1195                .unwrap(),
1196        )
1197    }
1198
1199    /// Restore the global of the given type after it is moved to the stack.
1200    pub(crate) fn end_global_lease<G: Global>(&mut self, lease: GlobalLease<G>) {
1201        let global_type = TypeId::of::<G>();
1202
1203        self.push_effect(Effect::NotifyGlobalObservers { global_type });
1204        self.globals_by_type.insert(global_type, lease.global);
1205    }
1206
1207    pub(crate) fn new_entity_observer(
1208        &self,
1209        key: TypeId,
1210        value: NewEntityListener,
1211    ) -> Subscription {
1212        let (subscription, activate) = self.new_entity_observers.insert(key, value);
1213        activate();
1214        subscription
1215    }
1216
1217    /// Arrange for the given function to be invoked whenever a view of the specified type is created.
1218    /// The function will be passed a mutable reference to the view along with an appropriate context.
1219    pub fn observe_new<T: 'static>(
1220        &self,
1221        on_new: impl 'static + Fn(&mut T, Option<&mut Window>, &mut Context<T>),
1222    ) -> Subscription {
1223        self.new_entity_observer(
1224            TypeId::of::<T>(),
1225            Box::new(
1226                move |any_entity: AnyEntity, window: &mut Option<&mut Window>, cx: &mut App| {
1227                    any_entity
1228                        .downcast::<T>()
1229                        .unwrap()
1230                        .update(cx, |entity_state, cx| {
1231                            if let Some(window) = window {
1232                                on_new(entity_state, Some(window), cx);
1233                            } else {
1234                                on_new(entity_state, None, cx);
1235                            }
1236                        })
1237                },
1238            ),
1239        )
1240    }
1241
1242    /// Observe the release of a entity. The callback is invoked after the entity
1243    /// has no more strong references but before it has been dropped.
1244    pub fn observe_release<T>(
1245        &self,
1246        handle: &Entity<T>,
1247        on_release: impl FnOnce(&mut T, &mut App) + 'static,
1248    ) -> Subscription
1249    where
1250        T: 'static,
1251    {
1252        let (subscription, activate) = self.release_listeners.insert(
1253            handle.entity_id(),
1254            Box::new(move |entity, cx| {
1255                let entity = entity.downcast_mut().expect("invalid entity type");
1256                on_release(entity, cx)
1257            }),
1258        );
1259        activate();
1260        subscription
1261    }
1262
1263    /// Observe the release of a entity. The callback is invoked after the entity
1264    /// has no more strong references but before it has been dropped.
1265    pub fn observe_release_in<T>(
1266        &self,
1267        handle: &Entity<T>,
1268        window: &Window,
1269        on_release: impl FnOnce(&mut T, &mut Window, &mut App) + 'static,
1270    ) -> Subscription
1271    where
1272        T: 'static,
1273    {
1274        let window_handle = window.handle;
1275        self.observe_release(&handle, move |entity, cx| {
1276            let _ = window_handle.update(cx, |_, window, cx| on_release(entity, window, cx));
1277        })
1278    }
1279
1280    /// Register a callback to be invoked when a keystroke is received by the application
1281    /// in any window. Note that this fires after all other action and event mechanisms have resolved
1282    /// and that this API will not be invoked if the event's propagation is stopped.
1283    pub fn observe_keystrokes(
1284        &mut self,
1285        mut f: impl FnMut(&KeystrokeEvent, &mut Window, &mut App) + 'static,
1286    ) -> Subscription {
1287        fn inner(
1288            keystroke_observers: &SubscriberSet<(), KeystrokeObserver>,
1289            handler: KeystrokeObserver,
1290        ) -> Subscription {
1291            let (subscription, activate) = keystroke_observers.insert((), handler);
1292            activate();
1293            subscription
1294        }
1295
1296        inner(
1297            &mut self.keystroke_observers,
1298            Box::new(move |event, window, cx| {
1299                f(event, window, cx);
1300                true
1301            }),
1302        )
1303    }
1304
1305    /// Register key bindings.
1306    pub fn bind_keys(&mut self, bindings: impl IntoIterator<Item = KeyBinding>) {
1307        self.keymap.borrow_mut().add_bindings(bindings);
1308        self.pending_effects.push_back(Effect::RefreshWindows);
1309    }
1310
1311    /// Clear all key bindings in the app.
1312    pub fn clear_key_bindings(&mut self) {
1313        self.keymap.borrow_mut().clear();
1314        self.pending_effects.push_back(Effect::RefreshWindows);
1315    }
1316
1317    /// Register a global listener for actions invoked via the keyboard.
1318    pub fn on_action<A: Action>(&mut self, listener: impl Fn(&A, &mut Self) + 'static) {
1319        self.global_action_listeners
1320            .entry(TypeId::of::<A>())
1321            .or_default()
1322            .push(Rc::new(move |action, phase, cx| {
1323                if phase == DispatchPhase::Bubble {
1324                    let action = action.downcast_ref().unwrap();
1325                    listener(action, cx)
1326                }
1327            }));
1328    }
1329
1330    /// Event handlers propagate events by default. Call this method to stop dispatching to
1331    /// event handlers with a lower z-index (mouse) or higher in the tree (keyboard). This is
1332    /// the opposite of [`Self::propagate`]. It's also possible to cancel a call to [`Self::propagate`] by
1333    /// calling this method before effects are flushed.
1334    pub fn stop_propagation(&mut self) {
1335        self.propagate_event = false;
1336    }
1337
1338    /// Action handlers stop propagation by default during the bubble phase of action dispatch
1339    /// dispatching to action handlers higher in the element tree. This is the opposite of
1340    /// [`Self::stop_propagation`]. It's also possible to cancel a call to [`Self::stop_propagation`] by calling
1341    /// this method before effects are flushed.
1342    pub fn propagate(&mut self) {
1343        self.propagate_event = true;
1344    }
1345
1346    /// Build an action from some arbitrary data, typically a keymap entry.
1347    pub fn build_action(
1348        &self,
1349        name: &str,
1350        data: Option<serde_json::Value>,
1351    ) -> std::result::Result<Box<dyn Action>, ActionBuildError> {
1352        self.actions.build_action(name, data)
1353    }
1354
1355    /// Get all action names that have been registered. Note that registration only allows for
1356    /// actions to be built dynamically, and is unrelated to binding actions in the element tree.
1357    pub fn all_action_names(&self) -> &[SharedString] {
1358        self.actions.all_action_names()
1359    }
1360
1361    /// Returns key bindings that invoke the given action on the currently focused element, without
1362    /// checking context. Bindings are returned in the order they were added. For display, the last
1363    /// binding should take precedence.
1364    pub fn all_bindings_for_input(&self, input: &[Keystroke]) -> Vec<KeyBinding> {
1365        RefCell::borrow(&self.keymap).all_bindings_for_input(input)
1366    }
1367
1368    /// Get all non-internal actions that have been registered, along with their schemas.
1369    pub fn action_schemas(
1370        &self,
1371        generator: &mut schemars::r#gen::SchemaGenerator,
1372    ) -> Vec<(SharedString, Option<schemars::schema::Schema>)> {
1373        self.actions.action_schemas(generator)
1374    }
1375
1376    /// Get a list of all deprecated action aliases and their canonical names.
1377    pub fn action_deprecations(&self) -> &HashMap<SharedString, SharedString> {
1378        self.actions.action_deprecations()
1379    }
1380
1381    /// Register a callback to be invoked when the application is about to quit.
1382    /// It is not possible to cancel the quit event at this point.
1383    pub fn on_app_quit<Fut>(
1384        &self,
1385        mut on_quit: impl FnMut(&mut App) -> Fut + 'static,
1386    ) -> Subscription
1387    where
1388        Fut: 'static + Future<Output = ()>,
1389    {
1390        let (subscription, activate) = self.quit_observers.insert(
1391            (),
1392            Box::new(move |cx| {
1393                let future = on_quit(cx);
1394                future.boxed_local()
1395            }),
1396        );
1397        activate();
1398        subscription
1399    }
1400
1401    /// Register a callback to be invoked when a window is closed
1402    /// The window is no longer accessible at the point this callback is invoked.
1403    pub fn on_window_closed(&self, mut on_closed: impl FnMut(&mut App) + 'static) -> Subscription {
1404        let (subscription, activate) = self.window_closed_observers.insert((), Box::new(on_closed));
1405        activate();
1406        subscription
1407    }
1408
1409    pub(crate) fn clear_pending_keystrokes(&mut self) {
1410        for window in self.windows() {
1411            window
1412                .update(self, |_, window, _| {
1413                    window.clear_pending_keystrokes();
1414                })
1415                .ok();
1416        }
1417    }
1418
1419    /// Checks if the given action is bound in the current context, as defined by the app's current focus,
1420    /// the bindings in the element tree, and any global action listeners.
1421    pub fn is_action_available(&mut self, action: &dyn Action) -> bool {
1422        let mut action_available = false;
1423        if let Some(window) = self.active_window() {
1424            if let Ok(window_action_available) =
1425                window.update(self, |_, window, cx| window.is_action_available(action, cx))
1426            {
1427                action_available = window_action_available;
1428            }
1429        }
1430
1431        action_available
1432            || self
1433                .global_action_listeners
1434                .contains_key(&action.as_any().type_id())
1435    }
1436
1437    /// Sets the menu bar for this application. This will replace any existing menu bar.
1438    pub fn set_menus(&self, menus: Vec<Menu>) {
1439        self.platform.set_menus(menus, &self.keymap.borrow());
1440    }
1441
1442    /// Gets the menu bar for this application.
1443    pub fn get_menus(&self) -> Option<Vec<OwnedMenu>> {
1444        self.platform.get_menus()
1445    }
1446
1447    /// Sets the right click menu for the app icon in the dock
1448    pub fn set_dock_menu(&self, menus: Vec<MenuItem>) {
1449        self.platform.set_dock_menu(menus, &self.keymap.borrow())
1450    }
1451
1452    /// Performs the action associated with the given dock menu item, only used on Windows for now.
1453    pub fn perform_dock_menu_action(&self, action: usize) {
1454        self.platform.perform_dock_menu_action(action);
1455    }
1456
1457    /// Adds given path to the bottom of the list of recent paths for the application.
1458    /// The list is usually shown on the application icon's context menu in the dock,
1459    /// and allows to open the recent files via that context menu.
1460    /// If the path is already in the list, it will be moved to the bottom of the list.
1461    pub fn add_recent_document(&self, path: &Path) {
1462        self.platform.add_recent_document(path);
1463    }
1464
1465    /// Updates the jump list with the updated list of recent paths for the application, only used on Windows for now.
1466    /// Note that this also sets the dock menu on Windows.
1467    pub fn update_jump_list(
1468        &self,
1469        menus: Vec<MenuItem>,
1470        entries: Vec<SmallVec<[PathBuf; 2]>>,
1471    ) -> Vec<SmallVec<[PathBuf; 2]>> {
1472        self.platform.update_jump_list(menus, entries)
1473    }
1474
1475    /// Dispatch an action to the currently active window or global action handler
1476    /// See [`crate::Action`] for more information on how actions work
1477    pub fn dispatch_action(&mut self, action: &dyn Action) {
1478        if let Some(active_window) = self.active_window() {
1479            active_window
1480                .update(self, |_, window, cx| {
1481                    window.dispatch_action(action.boxed_clone(), cx)
1482                })
1483                .log_err();
1484        } else {
1485            self.dispatch_global_action(action);
1486        }
1487    }
1488
1489    fn dispatch_global_action(&mut self, action: &dyn Action) {
1490        self.propagate_event = true;
1491
1492        if let Some(mut global_listeners) = self
1493            .global_action_listeners
1494            .remove(&action.as_any().type_id())
1495        {
1496            for listener in &global_listeners {
1497                listener(action.as_any(), DispatchPhase::Capture, self);
1498                if !self.propagate_event {
1499                    break;
1500                }
1501            }
1502
1503            global_listeners.extend(
1504                self.global_action_listeners
1505                    .remove(&action.as_any().type_id())
1506                    .unwrap_or_default(),
1507            );
1508
1509            self.global_action_listeners
1510                .insert(action.as_any().type_id(), global_listeners);
1511        }
1512
1513        if self.propagate_event {
1514            if let Some(mut global_listeners) = self
1515                .global_action_listeners
1516                .remove(&action.as_any().type_id())
1517            {
1518                for listener in global_listeners.iter().rev() {
1519                    listener(action.as_any(), DispatchPhase::Bubble, self);
1520                    if !self.propagate_event {
1521                        break;
1522                    }
1523                }
1524
1525                global_listeners.extend(
1526                    self.global_action_listeners
1527                        .remove(&action.as_any().type_id())
1528                        .unwrap_or_default(),
1529                );
1530
1531                self.global_action_listeners
1532                    .insert(action.as_any().type_id(), global_listeners);
1533            }
1534        }
1535    }
1536
1537    /// Is there currently something being dragged?
1538    pub fn has_active_drag(&self) -> bool {
1539        self.active_drag.is_some()
1540    }
1541
1542    /// Stops active drag and clears any related effects.
1543    pub fn stop_active_drag(&mut self, window: &mut Window) -> bool {
1544        if self.active_drag.is_some() {
1545            self.active_drag = None;
1546            window.refresh();
1547            true
1548        } else {
1549            false
1550        }
1551    }
1552
1553    /// Set the prompt renderer for GPUI. This will replace the default or platform specific
1554    /// prompts with this custom implementation.
1555    pub fn set_prompt_builder(
1556        &mut self,
1557        renderer: impl Fn(
1558            PromptLevel,
1559            &str,
1560            Option<&str>,
1561            &[&str],
1562            PromptHandle,
1563            &mut Window,
1564            &mut App,
1565        ) -> RenderablePromptHandle
1566        + 'static,
1567    ) {
1568        self.prompt_builder = Some(PromptBuilder::Custom(Box::new(renderer)))
1569    }
1570
1571    /// Reset the prompt builder to the default implementation.
1572    pub fn reset_prompt_builder(&mut self) {
1573        self.prompt_builder = Some(PromptBuilder::Default);
1574    }
1575
1576    /// Remove an asset from GPUI's cache
1577    pub fn remove_asset<A: Asset>(&mut self, source: &A::Source) {
1578        let asset_id = (TypeId::of::<A>(), hash(source));
1579        self.loading_assets.remove(&asset_id);
1580    }
1581
1582    /// Asynchronously load an asset, if the asset hasn't finished loading this will return None.
1583    ///
1584    /// Note that the multiple calls to this method will only result in one `Asset::load` call at a
1585    /// time, and the results of this call will be cached
1586    pub fn fetch_asset<A: Asset>(&mut self, source: &A::Source) -> (Shared<Task<A::Output>>, bool) {
1587        let asset_id = (TypeId::of::<A>(), hash(source));
1588        let mut is_first = false;
1589        let task = self
1590            .loading_assets
1591            .remove(&asset_id)
1592            .map(|boxed_task| *boxed_task.downcast::<Shared<Task<A::Output>>>().unwrap())
1593            .unwrap_or_else(|| {
1594                is_first = true;
1595                let future = A::load(source.clone(), self);
1596                let task = self.background_executor().spawn(future).shared();
1597                task
1598            });
1599
1600        self.loading_assets.insert(asset_id, Box::new(task.clone()));
1601
1602        (task, is_first)
1603    }
1604
1605    /// Obtain a new [`FocusHandle`], which allows you to track and manipulate the keyboard focus
1606    /// for elements rendered within this window.
1607    #[track_caller]
1608    pub fn focus_handle(&self) -> FocusHandle {
1609        FocusHandle::new(&self.focus_handles)
1610    }
1611
1612    /// Tell GPUI that an entity has changed and observers of it should be notified.
1613    pub fn notify(&mut self, entity_id: EntityId) {
1614        let window_invalidators = mem::take(
1615            self.window_invalidators_by_entity
1616                .entry(entity_id)
1617                .or_default(),
1618        );
1619
1620        if window_invalidators.is_empty() {
1621            if self.pending_notifications.insert(entity_id) {
1622                self.pending_effects
1623                    .push_back(Effect::Notify { emitter: entity_id });
1624            }
1625        } else {
1626            for invalidator in window_invalidators.values() {
1627                invalidator.invalidate_view(entity_id, self);
1628            }
1629        }
1630
1631        self.window_invalidators_by_entity
1632            .insert(entity_id, window_invalidators);
1633    }
1634
1635    /// Returns the name for this [`App`].
1636    #[cfg(any(test, feature = "test-support", debug_assertions))]
1637    pub fn get_name(&self) -> Option<&'static str> {
1638        self.name
1639    }
1640
1641    /// Returns `true` if the platform file picker supports selecting a mix of files and directories.
1642    pub fn can_select_mixed_files_and_dirs(&self) -> bool {
1643        self.platform.can_select_mixed_files_and_dirs()
1644    }
1645
1646    /// Removes an image from the sprite atlas on all windows.
1647    ///
1648    /// If the current window is being updated, it will be removed from `App.windows``, you can use `current_window` to specify the current window.
1649    /// This is a no-op if the image is not in the sprite atlas.
1650    pub fn drop_image(&mut self, image: Arc<RenderImage>, current_window: Option<&mut Window>) {
1651        // remove the texture from all other windows
1652        for window in self.windows.values_mut().flatten() {
1653            _ = window.drop_image(image.clone());
1654        }
1655
1656        // remove the texture from the current window
1657        if let Some(window) = current_window {
1658            _ = window.drop_image(image);
1659        }
1660    }
1661
1662    /// Initializes gpui's default colors for the application.
1663    ///
1664    /// These colors can be accessed through `cx.default_colors()`.
1665    pub fn init_colors(&mut self) {
1666        self.set_global(GlobalColors(Arc::new(Colors::default())));
1667    }
1668}
1669
1670impl AppContext for App {
1671    type Result<T> = T;
1672
1673    /// Builds an entity that is owned by the application.
1674    ///
1675    /// The given function will be invoked with a [`Context`] and must return an object representing the entity. An
1676    /// [`Entity`] handle will be returned, which can be used to access the entity in a context.
1677    fn new<T: 'static>(&mut self, build_entity: impl FnOnce(&mut Context<T>) -> T) -> Entity<T> {
1678        self.update(|cx| {
1679            let slot = cx.entities.reserve();
1680            let handle = slot.clone();
1681            let entity = build_entity(&mut Context::new_context(cx, slot.downgrade()));
1682
1683            cx.push_effect(Effect::EntityCreated {
1684                entity: handle.clone().into_any(),
1685                tid: TypeId::of::<T>(),
1686                window: cx.window_update_stack.last().cloned(),
1687            });
1688
1689            cx.entities.insert(slot, entity);
1690            handle
1691        })
1692    }
1693
1694    fn reserve_entity<T: 'static>(&mut self) -> Self::Result<Reservation<T>> {
1695        Reservation(self.entities.reserve())
1696    }
1697
1698    fn insert_entity<T: 'static>(
1699        &mut self,
1700        reservation: Reservation<T>,
1701        build_entity: impl FnOnce(&mut Context<T>) -> T,
1702    ) -> Self::Result<Entity<T>> {
1703        self.update(|cx| {
1704            let slot = reservation.0;
1705            let entity = build_entity(&mut Context::new_context(cx, slot.downgrade()));
1706            cx.entities.insert(slot, entity)
1707        })
1708    }
1709
1710    /// Updates the entity referenced by the given handle. The function is passed a mutable reference to the
1711    /// entity along with a `Context` for the entity.
1712    fn update_entity<T: 'static, R>(
1713        &mut self,
1714        handle: &Entity<T>,
1715        update: impl FnOnce(&mut T, &mut Context<T>) -> R,
1716    ) -> R {
1717        self.update(|cx| {
1718            let mut entity = cx.entities.lease(handle);
1719            let result = update(
1720                &mut entity,
1721                &mut Context::new_context(cx, handle.downgrade()),
1722            );
1723            cx.entities.end_lease(entity);
1724            result
1725        })
1726    }
1727
1728    fn read_entity<T, R>(
1729        &self,
1730        handle: &Entity<T>,
1731        read: impl FnOnce(&T, &App) -> R,
1732    ) -> Self::Result<R>
1733    where
1734        T: 'static,
1735    {
1736        let entity = self.entities.read(handle);
1737        read(entity, self)
1738    }
1739
1740    fn update_window<T, F>(&mut self, handle: AnyWindowHandle, update: F) -> Result<T>
1741    where
1742        F: FnOnce(AnyView, &mut Window, &mut App) -> T,
1743    {
1744        self.update_window_id(handle.id, update)
1745    }
1746
1747    fn read_window<T, R>(
1748        &self,
1749        window: &WindowHandle<T>,
1750        read: impl FnOnce(Entity<T>, &App) -> R,
1751    ) -> Result<R>
1752    where
1753        T: 'static,
1754    {
1755        let window = self
1756            .windows
1757            .get(window.id)
1758            .ok_or_else(|| anyhow!("window not found"))?
1759            .as_ref()
1760            .expect("attempted to read a window that is already on the stack");
1761
1762        let root_view = window.root.clone().unwrap();
1763        let view = root_view
1764            .downcast::<T>()
1765            .map_err(|_| anyhow!("root view's type has changed"))?;
1766
1767        Ok(read(view, self))
1768    }
1769
1770    fn background_spawn<R>(&self, future: impl Future<Output = R> + Send + 'static) -> Task<R>
1771    where
1772        R: Send + 'static,
1773    {
1774        self.background_executor.spawn(future)
1775    }
1776
1777    fn read_global<G, R>(&self, callback: impl FnOnce(&G, &App) -> R) -> Self::Result<R>
1778    where
1779        G: Global,
1780    {
1781        let mut g = self.global::<G>();
1782        callback(&g, self)
1783    }
1784}
1785
1786/// These effects are processed at the end of each application update cycle.
1787pub(crate) enum Effect {
1788    Notify {
1789        emitter: EntityId,
1790    },
1791    Emit {
1792        emitter: EntityId,
1793        event_type: TypeId,
1794        event: Box<dyn Any>,
1795    },
1796    RefreshWindows,
1797    NotifyGlobalObservers {
1798        global_type: TypeId,
1799    },
1800    Defer {
1801        callback: Box<dyn FnOnce(&mut App) + 'static>,
1802    },
1803    EntityCreated {
1804        entity: AnyEntity,
1805        tid: TypeId,
1806        window: Option<WindowId>,
1807    },
1808}
1809
1810impl std::fmt::Debug for Effect {
1811    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
1812        match self {
1813            Effect::Notify { emitter } => write!(f, "Notify({})", emitter),
1814            Effect::Emit { emitter, .. } => write!(f, "Emit({:?})", emitter),
1815            Effect::RefreshWindows => write!(f, "RefreshWindows"),
1816            Effect::NotifyGlobalObservers { global_type } => {
1817                write!(f, "NotifyGlobalObservers({:?})", global_type)
1818            }
1819            Effect::Defer { .. } => write!(f, "Defer(..)"),
1820            Effect::EntityCreated { entity, .. } => write!(f, "EntityCreated({:?})", entity),
1821        }
1822    }
1823}
1824
1825/// Wraps a global variable value during `update_global` while the value has been moved to the stack.
1826pub(crate) struct GlobalLease<G: Global> {
1827    global: Box<dyn Any>,
1828    global_type: PhantomData<G>,
1829}
1830
1831impl<G: Global> GlobalLease<G> {
1832    fn new(global: Box<dyn Any>) -> Self {
1833        GlobalLease {
1834            global,
1835            global_type: PhantomData,
1836        }
1837    }
1838}
1839
1840impl<G: Global> Deref for GlobalLease<G> {
1841    type Target = G;
1842
1843    fn deref(&self) -> &Self::Target {
1844        self.global.downcast_ref().unwrap()
1845    }
1846}
1847
1848impl<G: Global> DerefMut for GlobalLease<G> {
1849    fn deref_mut(&mut self) -> &mut Self::Target {
1850        self.global.downcast_mut().unwrap()
1851    }
1852}
1853
1854/// Contains state associated with an active drag operation, started by dragging an element
1855/// within the window or by dragging into the app from the underlying platform.
1856pub struct AnyDrag {
1857    /// The view used to render this drag
1858    pub view: AnyView,
1859
1860    /// The value of the dragged item, to be dropped
1861    pub value: Arc<dyn Any>,
1862
1863    /// This is used to render the dragged item in the same place
1864    /// on the original element that the drag was initiated
1865    pub cursor_offset: Point<Pixels>,
1866
1867    /// The cursor style to use while dragging
1868    pub cursor_style: Option<CursorStyle>,
1869}
1870
1871/// Contains state associated with a tooltip. You'll only need this struct if you're implementing
1872/// tooltip behavior on a custom element. Otherwise, use [Div::tooltip].
1873#[derive(Clone)]
1874pub struct AnyTooltip {
1875    /// The view used to display the tooltip
1876    pub view: AnyView,
1877
1878    /// The absolute position of the mouse when the tooltip was deployed.
1879    pub mouse_position: Point<Pixels>,
1880
1881    /// Given the bounds of the tooltip, checks whether the tooltip should still be visible and
1882    /// updates its state accordingly. This is needed atop the hovered element's mouse move handler
1883    /// to handle the case where the element is not painted (e.g. via use of `visible_on_hover`).
1884    pub check_visible_and_update: Rc<dyn Fn(Bounds<Pixels>, &mut Window, &mut App) -> bool>,
1885}
1886
1887/// A keystroke event, and potentially the associated action
1888#[derive(Debug)]
1889pub struct KeystrokeEvent {
1890    /// The keystroke that occurred
1891    pub keystroke: Keystroke,
1892
1893    /// The action that was resolved for the keystroke, if any
1894    pub action: Option<Box<dyn Action>>,
1895
1896    /// The context stack at the time
1897    pub context_stack: Vec<KeyContext>,
1898}
1899
1900struct NullHttpClient;
1901
1902impl HttpClient for NullHttpClient {
1903    fn send(
1904        &self,
1905        _req: http_client::Request<http_client::AsyncBody>,
1906    ) -> futures::future::BoxFuture<
1907        'static,
1908        Result<http_client::Response<http_client::AsyncBody>, anyhow::Error>,
1909    > {
1910        async move { Err(anyhow!("No HttpClient available")) }.boxed()
1911    }
1912
1913    fn proxy(&self) -> Option<&Url> {
1914        None
1915    }
1916
1917    fn type_name(&self) -> &'static str {
1918        type_name::<Self>()
1919    }
1920}