window.rs

   1use crate::{
   2    elements::AnyRootElement,
   3    geometry::rect::RectF,
   4    json::{self, ToJson},
   5    keymap_matcher::{Binding, Keystroke, MatchResult},
   6    platform::{
   7        self, Appearance, CursorStyle, Event, KeyDownEvent, KeyUpEvent, ModifiersChangedEvent,
   8        MouseButton, MouseMovedEvent, PromptLevel, WindowBounds,
   9    },
  10    scene::{
  11        CursorRegion, MouseClick, MouseDown, MouseDownOut, MouseDrag, MouseEvent, MouseHover,
  12        MouseMove, MouseMoveOut, MouseScrollWheel, MouseUp, MouseUpOut, Scene,
  13    },
  14    text_layout::TextLayoutCache,
  15    util::post_inc,
  16    Action, AnyModelHandle, AnyView, AnyViewHandle, AnyWeakModelHandle, AnyWeakViewHandle,
  17    AppContext, Drawable, Effect, Entity, Handle, ModelContext, ModelHandle, MouseRegion,
  18    MouseRegionId, ParentId, ReadModel, ReadView, SceneBuilder, Subscription, UpdateModel,
  19    UpdateView, UpgradeModelHandle, UpgradeViewHandle, View, ViewContext, ViewHandle,
  20    WeakModelHandle, WeakViewHandle, WindowInvalidation,
  21};
  22use anyhow::{anyhow, bail, Result};
  23use collections::{HashMap, HashSet};
  24use pathfinder_geometry::vector::{vec2f, Vector2F};
  25use postage::oneshot;
  26use serde_json::json;
  27use smallvec::SmallVec;
  28use sqlez::{
  29    bindable::{Bind, Column, StaticColumnCount},
  30    statement::Statement,
  31};
  32use std::{
  33    any::TypeId,
  34    ops::{Deref, DerefMut, Range},
  35};
  36use util::ResultExt;
  37use uuid::Uuid;
  38
  39use super::Reference;
  40
  41pub struct Window {
  42    pub(crate) root_view: Option<AnyViewHandle>,
  43    pub(crate) focused_view_id: Option<usize>,
  44    pub(crate) is_active: bool,
  45    pub(crate) is_fullscreen: bool,
  46    pub(crate) invalidation: Option<WindowInvalidation>,
  47    pub(crate) platform_window: Box<dyn platform::Window>,
  48    pub(crate) rendered_views: HashMap<usize, Box<dyn AnyRootElement>>,
  49    titlebar_height: f32,
  50    appearance: Appearance,
  51    cursor_regions: Vec<CursorRegion>,
  52    mouse_regions: Vec<(MouseRegion, usize)>,
  53    last_mouse_moved_event: Option<Event>,
  54    pub(crate) hovered_region_ids: HashSet<MouseRegionId>,
  55    pub(crate) clicked_region_ids: HashSet<MouseRegionId>,
  56    pub(crate) clicked_button: Option<MouseButton>,
  57    mouse_position: Vector2F,
  58    text_layout_cache: TextLayoutCache,
  59}
  60
  61impl Window {
  62    pub fn new<V, F>(
  63        window_id: usize,
  64        platform_window: Box<dyn platform::Window>,
  65        cx: &mut AppContext,
  66        build_view: F,
  67    ) -> Self
  68    where
  69        F: FnOnce(&mut ViewContext<V>) -> V,
  70        V: View,
  71    {
  72        let titlebar_height = platform_window.titlebar_height();
  73        let appearance = platform_window.appearance();
  74        let mut window = Self {
  75            root_view: None,
  76            focused_view_id: None,
  77            is_active: false,
  78            invalidation: None,
  79            is_fullscreen: false,
  80            platform_window,
  81            rendered_views: Default::default(),
  82            cursor_regions: Default::default(),
  83            mouse_regions: Default::default(),
  84            text_layout_cache: TextLayoutCache::new(cx.font_system.clone()),
  85            last_mouse_moved_event: None,
  86            hovered_region_ids: Default::default(),
  87            clicked_region_ids: Default::default(),
  88            clicked_button: None,
  89            mouse_position: vec2f(0., 0.),
  90            titlebar_height,
  91            appearance,
  92        };
  93
  94        let mut window_context = WindowContext::mutable(cx, &mut window, window_id);
  95        let root_view = window_context
  96            .build_and_insert_view(ParentId::Root, |cx| Some(build_view(cx)))
  97            .unwrap();
  98        if let Some(mut invalidation) = window_context.window.invalidation.take() {
  99            window_context.invalidate(&mut invalidation, appearance);
 100        }
 101        window.focused_view_id = Some(root_view.id());
 102        window.root_view = Some(root_view.into_any());
 103        window
 104    }
 105
 106    pub fn root_view(&self) -> &AnyViewHandle {
 107        &self
 108            .root_view
 109            .as_ref()
 110            .expect("root_view called during window construction")
 111    }
 112}
 113
 114pub struct WindowContext<'a: 'b, 'b> {
 115    pub(crate) app_context: Reference<'a, AppContext>,
 116    pub(crate) window: Reference<'b, Window>,
 117    pub(crate) window_id: usize,
 118    pub(crate) refreshing: bool,
 119}
 120
 121impl Deref for WindowContext<'_, '_> {
 122    type Target = AppContext;
 123
 124    fn deref(&self) -> &Self::Target {
 125        &self.app_context
 126    }
 127}
 128
 129impl DerefMut for WindowContext<'_, '_> {
 130    fn deref_mut(&mut self) -> &mut Self::Target {
 131        &mut self.app_context
 132    }
 133}
 134
 135impl ReadModel for WindowContext<'_, '_> {
 136    fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
 137        self.app_context.read_model(handle)
 138    }
 139}
 140
 141impl UpdateModel for WindowContext<'_, '_> {
 142    fn update_model<T: Entity, R>(
 143        &mut self,
 144        handle: &ModelHandle<T>,
 145        update: &mut dyn FnMut(&mut T, &mut ModelContext<T>) -> R,
 146    ) -> R {
 147        self.app_context.update_model(handle, update)
 148    }
 149}
 150
 151impl ReadView for WindowContext<'_, '_> {
 152    fn read_view<W: View>(&self, handle: &crate::ViewHandle<W>) -> &W {
 153        self.app_context.read_view(handle)
 154    }
 155}
 156
 157impl UpdateView for WindowContext<'_, '_> {
 158    type Output<S> = S;
 159
 160    fn update_view<T, S>(
 161        &mut self,
 162        handle: &ViewHandle<T>,
 163        update: &mut dyn FnMut(&mut T, &mut ViewContext<T>) -> S,
 164    ) -> S
 165    where
 166        T: View,
 167    {
 168        self.update_any_view(handle.view_id, |view, cx| {
 169            let mut cx = ViewContext::mutable(cx, handle.view_id);
 170            update(
 171                view.as_any_mut()
 172                    .downcast_mut()
 173                    .expect("downcast is type safe"),
 174                &mut cx,
 175            )
 176        })
 177        .unwrap()
 178    }
 179}
 180
 181impl UpgradeModelHandle for WindowContext<'_, '_> {
 182    fn upgrade_model_handle<T: Entity>(
 183        &self,
 184        handle: &WeakModelHandle<T>,
 185    ) -> Option<ModelHandle<T>> {
 186        self.app_context.upgrade_model_handle(handle)
 187    }
 188
 189    fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
 190        self.app_context.model_handle_is_upgradable(handle)
 191    }
 192
 193    fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
 194        self.app_context.upgrade_any_model_handle(handle)
 195    }
 196}
 197
 198impl UpgradeViewHandle for WindowContext<'_, '_> {
 199    fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
 200        self.app_context.upgrade_view_handle(handle)
 201    }
 202
 203    fn upgrade_any_view_handle(&self, handle: &AnyWeakViewHandle) -> Option<AnyViewHandle> {
 204        self.app_context.upgrade_any_view_handle(handle)
 205    }
 206}
 207
 208impl<'a: 'b, 'b> WindowContext<'a, 'b> {
 209    pub fn mutable(
 210        app_context: &'a mut AppContext,
 211        window: &'b mut Window,
 212        window_id: usize,
 213    ) -> Self {
 214        Self {
 215            app_context: Reference::Mutable(app_context),
 216            window: Reference::Mutable(window),
 217            window_id,
 218            refreshing: false,
 219        }
 220    }
 221
 222    pub fn immutable(app_context: &'a AppContext, window: &'b Window, window_id: usize) -> Self {
 223        Self {
 224            app_context: Reference::Immutable(app_context),
 225            window: Reference::Immutable(window),
 226            window_id,
 227            refreshing: false,
 228        }
 229    }
 230
 231    pub fn window_id(&self) -> usize {
 232        self.window_id
 233    }
 234
 235    pub fn app_context(&mut self) -> &mut AppContext {
 236        &mut self.app_context
 237    }
 238
 239    pub fn root_view(&self) -> &AnyViewHandle {
 240        self.window.root_view()
 241    }
 242
 243    pub fn window_size(&self) -> Vector2F {
 244        self.window.platform_window.content_size()
 245    }
 246
 247    pub fn text_layout_cache(&self) -> &TextLayoutCache {
 248        &self.window.text_layout_cache
 249    }
 250
 251    pub(crate) fn update_any_view<F, T>(&mut self, view_id: usize, f: F) -> Option<T>
 252    where
 253        F: FnOnce(&mut dyn AnyView, &mut Self) -> T,
 254    {
 255        let window_id = self.window_id;
 256        let mut view = self.views.remove(&(window_id, view_id))?;
 257        let result = f(view.as_mut(), self);
 258        self.views.insert((window_id, view_id), view);
 259        Some(result)
 260    }
 261
 262    pub fn defer(&mut self, callback: impl 'static + FnOnce(&mut WindowContext)) {
 263        let window_id = self.window_id;
 264        self.app_context.defer(move |cx| {
 265            cx.update_window(window_id, |cx| callback(cx));
 266        })
 267    }
 268
 269    pub fn update_global<T, F, U>(&mut self, update: F) -> U
 270    where
 271        T: 'static,
 272        F: FnOnce(&mut T, &mut Self) -> U,
 273    {
 274        AppContext::update_global_internal(self, |global, cx| update(global, cx))
 275    }
 276
 277    pub fn subscribe<E, H, F>(&mut self, handle: &H, mut callback: F) -> Subscription
 278    where
 279        E: Entity,
 280        E::Event: 'static,
 281        H: Handle<E>,
 282        F: 'static + FnMut(H, &E::Event, &mut WindowContext),
 283    {
 284        self.subscribe_internal(handle, move |emitter, event, cx| {
 285            callback(emitter, event, cx);
 286            true
 287        })
 288    }
 289
 290    pub fn subscribe_internal<E, H, F>(&mut self, handle: &H, mut callback: F) -> Subscription
 291    where
 292        E: Entity,
 293        E::Event: 'static,
 294        H: Handle<E>,
 295        F: 'static + FnMut(H, &E::Event, &mut WindowContext) -> bool,
 296    {
 297        let window_id = self.window_id;
 298        self.app_context
 299            .subscribe_internal(handle, move |emitter, event, cx| {
 300                cx.update_window(window_id, |cx| callback(emitter, event, cx))
 301                    .unwrap_or(false)
 302            })
 303    }
 304
 305    pub(crate) fn observe_window_activation<F>(&mut self, callback: F) -> Subscription
 306    where
 307        F: 'static + FnMut(bool, &mut WindowContext) -> bool,
 308    {
 309        let window_id = self.window_id;
 310        let subscription_id = post_inc(&mut self.next_subscription_id);
 311        self.pending_effects
 312            .push_back(Effect::WindowActivationObservation {
 313                window_id,
 314                subscription_id,
 315                callback: Box::new(callback),
 316            });
 317        Subscription::WindowActivationObservation(
 318            self.window_activation_observations
 319                .subscribe(window_id, subscription_id),
 320        )
 321    }
 322
 323    pub(crate) fn observe_fullscreen<F>(&mut self, callback: F) -> Subscription
 324    where
 325        F: 'static + FnMut(bool, &mut WindowContext) -> bool,
 326    {
 327        let window_id = self.window_id;
 328        let subscription_id = post_inc(&mut self.next_subscription_id);
 329        self.pending_effects
 330            .push_back(Effect::WindowFullscreenObservation {
 331                window_id,
 332                subscription_id,
 333                callback: Box::new(callback),
 334            });
 335        Subscription::WindowActivationObservation(
 336            self.window_activation_observations
 337                .subscribe(window_id, subscription_id),
 338        )
 339    }
 340
 341    pub(crate) fn observe_window_bounds<F>(&mut self, callback: F) -> Subscription
 342    where
 343        F: 'static + FnMut(WindowBounds, Uuid, &mut WindowContext) -> bool,
 344    {
 345        let window_id = self.window_id;
 346        let subscription_id = post_inc(&mut self.next_subscription_id);
 347        self.pending_effects
 348            .push_back(Effect::WindowBoundsObservation {
 349                window_id,
 350                subscription_id,
 351                callback: Box::new(callback),
 352            });
 353        Subscription::WindowBoundsObservation(
 354            self.window_bounds_observations
 355                .subscribe(window_id, subscription_id),
 356        )
 357    }
 358
 359    pub fn observe_keystrokes<F>(&mut self, callback: F) -> Subscription
 360    where
 361        F: 'static
 362            + FnMut(&Keystroke, &MatchResult, Option<&Box<dyn Action>>, &mut WindowContext) -> bool,
 363    {
 364        let window_id = self.window_id;
 365        let subscription_id = post_inc(&mut self.next_subscription_id);
 366        self.keystroke_observations
 367            .add_callback(window_id, subscription_id, Box::new(callback));
 368        Subscription::KeystrokeObservation(
 369            self.keystroke_observations
 370                .subscribe(window_id, subscription_id),
 371        )
 372    }
 373
 374    /// Return keystrokes that would dispatch the given action on the given view.
 375    pub(crate) fn keystrokes_for_action(
 376        &mut self,
 377        view_id: usize,
 378        action: &dyn Action,
 379    ) -> Option<SmallVec<[Keystroke; 2]>> {
 380        let window_id = self.window_id;
 381        let mut contexts = Vec::new();
 382        let mut handler_depth = None;
 383        for (i, view_id) in self.ancestors(view_id).enumerate() {
 384            if let Some(view) = self.views.get(&(window_id, view_id)) {
 385                if let Some(actions) = self.actions.get(&view.as_any().type_id()) {
 386                    if actions.contains_key(&action.as_any().type_id()) {
 387                        handler_depth = Some(i);
 388                    }
 389                }
 390                contexts.push(view.keymap_context(self));
 391            }
 392        }
 393
 394        if self.global_actions.contains_key(&action.as_any().type_id()) {
 395            handler_depth = Some(contexts.len())
 396        }
 397
 398        self.keystroke_matcher
 399            .bindings_for_action_type(action.as_any().type_id())
 400            .find_map(|b| {
 401                handler_depth
 402                    .map(|highest_handler| {
 403                        if (0..=highest_handler).any(|depth| b.match_context(&contexts[depth..])) {
 404                            Some(b.keystrokes().into())
 405                        } else {
 406                            None
 407                        }
 408                    })
 409                    .flatten()
 410            })
 411    }
 412
 413    pub fn available_actions(
 414        &self,
 415        view_id: usize,
 416    ) -> impl Iterator<Item = (&'static str, Box<dyn Action>, SmallVec<[&Binding; 1]>)> {
 417        let window_id = self.window_id;
 418        let mut contexts = Vec::new();
 419        let mut handler_depths_by_action_type = HashMap::<TypeId, usize>::default();
 420        for (depth, view_id) in self.ancestors(view_id).enumerate() {
 421            if let Some(view) = self.views.get(&(window_id, view_id)) {
 422                contexts.push(view.keymap_context(self));
 423                let view_type = view.as_any().type_id();
 424                if let Some(actions) = self.actions.get(&view_type) {
 425                    handler_depths_by_action_type.extend(
 426                        actions
 427                            .keys()
 428                            .copied()
 429                            .map(|action_type| (action_type, depth)),
 430                    );
 431                }
 432            }
 433        }
 434
 435        handler_depths_by_action_type.extend(
 436            self.global_actions
 437                .keys()
 438                .copied()
 439                .map(|action_type| (action_type, contexts.len())),
 440        );
 441
 442        self.action_deserializers
 443            .iter()
 444            .filter_map(move |(name, (type_id, deserialize))| {
 445                if let Some(action_depth) = handler_depths_by_action_type.get(type_id).copied() {
 446                    Some((
 447                        *name,
 448                        deserialize("{}").ok()?,
 449                        self.keystroke_matcher
 450                            .bindings_for_action_type(*type_id)
 451                            .filter(|b| {
 452                                (0..=action_depth).any(|depth| b.match_context(&contexts[depth..]))
 453                            })
 454                            .collect(),
 455                    ))
 456                } else {
 457                    None
 458                }
 459            })
 460    }
 461
 462    pub fn dispatch_keystroke(&mut self, keystroke: &Keystroke) -> bool {
 463        let window_id = self.window_id;
 464        if let Some(focused_view_id) = self.focused_view_id() {
 465            let dispatch_path = self
 466                .ancestors(focused_view_id)
 467                .filter_map(|view_id| {
 468                    self.views
 469                        .get(&(window_id, view_id))
 470                        .map(|view| (view_id, view.keymap_context(self)))
 471                })
 472                .collect();
 473
 474            let match_result = self
 475                .keystroke_matcher
 476                .push_keystroke(keystroke.clone(), dispatch_path);
 477            let mut handled_by = None;
 478
 479            let keystroke_handled = match &match_result {
 480                MatchResult::None => false,
 481                MatchResult::Pending => true,
 482                MatchResult::Matches(matches) => {
 483                    for (view_id, action) in matches {
 484                        if self.handle_dispatch_action_from_effect(Some(*view_id), action.as_ref())
 485                        {
 486                            self.keystroke_matcher.clear_pending();
 487                            handled_by = Some(action.boxed_clone());
 488                            break;
 489                        }
 490                    }
 491                    handled_by.is_some()
 492                }
 493            };
 494
 495            self.keystroke(
 496                window_id,
 497                keystroke.clone(),
 498                handled_by,
 499                match_result.clone(),
 500            );
 501            keystroke_handled
 502        } else {
 503            self.keystroke(window_id, keystroke.clone(), None, MatchResult::None);
 504            false
 505        }
 506    }
 507
 508    pub fn dispatch_event(&mut self, event: Event, event_reused: bool) -> bool {
 509        let mut mouse_events = SmallVec::<[_; 2]>::new();
 510        let mut notified_views: HashSet<usize> = Default::default();
 511        let window_id = self.window_id;
 512
 513        // 1. Handle platform event. Keyboard events get dispatched immediately, while mouse events
 514        //    get mapped into the mouse-specific MouseEvent type.
 515        //  -> These are usually small: [Mouse Down] or [Mouse up, Click] or [Mouse Moved, Mouse Dragged?]
 516        //  -> Also updates mouse-related state
 517        match &event {
 518            Event::KeyDown(e) => return self.dispatch_key_down(e),
 519
 520            Event::KeyUp(e) => return self.dispatch_key_up(e),
 521
 522            Event::ModifiersChanged(e) => return self.dispatch_modifiers_changed(e),
 523
 524            Event::MouseDown(e) => {
 525                // Click events are weird because they can be fired after a drag event.
 526                // MDN says that browsers handle this by starting from 'the most
 527                // specific ancestor element that contained both [positions]'
 528                // So we need to store the overlapping regions on mouse down.
 529
 530                // If there is already clicked_button stored, don't replace it.
 531                if self.window.clicked_button.is_none() {
 532                    self.window.clicked_region_ids = self
 533                        .window
 534                        .mouse_regions
 535                        .iter()
 536                        .filter_map(|(region, _)| {
 537                            if region.bounds.contains_point(e.position) {
 538                                Some(region.id())
 539                            } else {
 540                                None
 541                            }
 542                        })
 543                        .collect();
 544
 545                    self.window.clicked_button = Some(e.button);
 546                }
 547
 548                mouse_events.push(MouseEvent::Down(MouseDown {
 549                    region: Default::default(),
 550                    platform_event: e.clone(),
 551                }));
 552                mouse_events.push(MouseEvent::DownOut(MouseDownOut {
 553                    region: Default::default(),
 554                    platform_event: e.clone(),
 555                }));
 556            }
 557
 558            Event::MouseUp(e) => {
 559                // NOTE: The order of event pushes is important! MouseUp events MUST be fired
 560                // before click events, and so the MouseUp events need to be pushed before
 561                // MouseClick events.
 562                mouse_events.push(MouseEvent::Up(MouseUp {
 563                    region: Default::default(),
 564                    platform_event: e.clone(),
 565                }));
 566                mouse_events.push(MouseEvent::UpOut(MouseUpOut {
 567                    region: Default::default(),
 568                    platform_event: e.clone(),
 569                }));
 570                mouse_events.push(MouseEvent::Click(MouseClick {
 571                    region: Default::default(),
 572                    platform_event: e.clone(),
 573                }));
 574            }
 575
 576            Event::MouseMoved(
 577                e @ MouseMovedEvent {
 578                    position,
 579                    pressed_button,
 580                    ..
 581                },
 582            ) => {
 583                let mut style_to_assign = CursorStyle::Arrow;
 584                for region in self.window.cursor_regions.iter().rev() {
 585                    if region.bounds.contains_point(*position) {
 586                        style_to_assign = region.style;
 587                        break;
 588                    }
 589                }
 590
 591                if self
 592                    .window
 593                    .platform_window
 594                    .is_topmost_for_position(*position)
 595                {
 596                    self.platform().set_cursor_style(style_to_assign);
 597                }
 598
 599                if !event_reused {
 600                    if pressed_button.is_some() {
 601                        mouse_events.push(MouseEvent::Drag(MouseDrag {
 602                            region: Default::default(),
 603                            prev_mouse_position: self.window.mouse_position,
 604                            platform_event: e.clone(),
 605                        }));
 606                    } else if let Some(clicked_button) = self.window.clicked_button {
 607                        // Mouse up event happened outside the current window. Simulate mouse up button event
 608                        let button_event = e.to_button_event(clicked_button);
 609                        mouse_events.push(MouseEvent::Up(MouseUp {
 610                            region: Default::default(),
 611                            platform_event: button_event.clone(),
 612                        }));
 613                        mouse_events.push(MouseEvent::UpOut(MouseUpOut {
 614                            region: Default::default(),
 615                            platform_event: button_event.clone(),
 616                        }));
 617                        mouse_events.push(MouseEvent::Click(MouseClick {
 618                            region: Default::default(),
 619                            platform_event: button_event.clone(),
 620                        }));
 621                    }
 622
 623                    mouse_events.push(MouseEvent::Move(MouseMove {
 624                        region: Default::default(),
 625                        platform_event: e.clone(),
 626                    }));
 627                }
 628
 629                mouse_events.push(MouseEvent::Hover(MouseHover {
 630                    region: Default::default(),
 631                    platform_event: e.clone(),
 632                    started: false,
 633                }));
 634                mouse_events.push(MouseEvent::MoveOut(MouseMoveOut {
 635                    region: Default::default(),
 636                }));
 637
 638                self.window.last_mouse_moved_event = Some(event.clone());
 639            }
 640
 641            Event::MouseExited(event) => {
 642                // When the platform sends a MouseExited event, synthesize
 643                // a MouseMoved event whose position is outside the window's
 644                // bounds so that hover and cursor state can be updated.
 645                return self.dispatch_event(
 646                    Event::MouseMoved(MouseMovedEvent {
 647                        position: event.position,
 648                        pressed_button: event.pressed_button,
 649                        modifiers: event.modifiers,
 650                    }),
 651                    event_reused,
 652                );
 653            }
 654
 655            Event::ScrollWheel(e) => mouse_events.push(MouseEvent::ScrollWheel(MouseScrollWheel {
 656                region: Default::default(),
 657                platform_event: e.clone(),
 658            })),
 659        }
 660
 661        if let Some(position) = event.position() {
 662            self.window.mouse_position = position;
 663        }
 664
 665        // 2. Dispatch mouse events on regions
 666        let mut any_event_handled = false;
 667        for mut mouse_event in mouse_events {
 668            let mut valid_regions = Vec::new();
 669
 670            // GPUI elements are arranged by z_index but sibling elements can register overlapping
 671            // mouse regions. As such, hover events are only fired on overlapping elements which
 672            // are at the same z-index as the topmost element which overlaps with the mouse.
 673            match &mouse_event {
 674                MouseEvent::Hover(_) => {
 675                    let mut highest_z_index = None;
 676                    let mouse_position = self.window.mouse_position.clone();
 677                    let window = &mut *self.window;
 678                    for (region, z_index) in window.mouse_regions.iter().rev() {
 679                        // Allow mouse regions to appear transparent to hovers
 680                        if !region.hoverable {
 681                            continue;
 682                        }
 683
 684                        let contains_mouse = region.bounds.contains_point(mouse_position);
 685
 686                        if contains_mouse && highest_z_index.is_none() {
 687                            highest_z_index = Some(z_index);
 688                        }
 689
 690                        // This unwrap relies on short circuiting boolean expressions
 691                        // The right side of the && is only executed when contains_mouse
 692                        // is true, and we know above that when contains_mouse is true
 693                        // highest_z_index is set.
 694                        if contains_mouse && z_index == highest_z_index.unwrap() {
 695                            //Ensure that hover entrance events aren't sent twice
 696                            if window.hovered_region_ids.insert(region.id()) {
 697                                valid_regions.push(region.clone());
 698                                if region.notify_on_hover {
 699                                    notified_views.insert(region.id().view_id());
 700                                }
 701                            }
 702                        } else {
 703                            // Ensure that hover exit events aren't sent twice
 704                            if window.hovered_region_ids.remove(&region.id()) {
 705                                valid_regions.push(region.clone());
 706                                if region.notify_on_hover {
 707                                    notified_views.insert(region.id().view_id());
 708                                }
 709                            }
 710                        }
 711                    }
 712                }
 713
 714                MouseEvent::Down(_) | MouseEvent::Up(_) => {
 715                    for (region, _) in self.window.mouse_regions.iter().rev() {
 716                        if region.bounds.contains_point(self.window.mouse_position) {
 717                            valid_regions.push(region.clone());
 718                            if region.notify_on_click {
 719                                notified_views.insert(region.id().view_id());
 720                            }
 721                        }
 722                    }
 723                }
 724
 725                MouseEvent::Click(e) => {
 726                    // Only raise click events if the released button is the same as the one stored
 727                    if self
 728                        .window
 729                        .clicked_button
 730                        .map(|clicked_button| clicked_button == e.button)
 731                        .unwrap_or(false)
 732                    {
 733                        // Clear clicked regions and clicked button
 734                        let clicked_region_ids = std::mem::replace(
 735                            &mut self.window.clicked_region_ids,
 736                            Default::default(),
 737                        );
 738                        self.window.clicked_button = None;
 739
 740                        // Find regions which still overlap with the mouse since the last MouseDown happened
 741                        for (mouse_region, _) in self.window.mouse_regions.iter().rev() {
 742                            if clicked_region_ids.contains(&mouse_region.id()) {
 743                                if mouse_region
 744                                    .bounds
 745                                    .contains_point(self.window.mouse_position)
 746                                {
 747                                    valid_regions.push(mouse_region.clone());
 748                                }
 749                            }
 750                        }
 751                    }
 752                }
 753
 754                MouseEvent::Drag(_) => {
 755                    for (mouse_region, _) in self.window.mouse_regions.iter().rev() {
 756                        if self.window.clicked_region_ids.contains(&mouse_region.id()) {
 757                            valid_regions.push(mouse_region.clone());
 758                        }
 759                    }
 760                }
 761
 762                MouseEvent::MoveOut(_) | MouseEvent::UpOut(_) | MouseEvent::DownOut(_) => {
 763                    for (mouse_region, _) in self.window.mouse_regions.iter().rev() {
 764                        // NOT contains
 765                        if !mouse_region
 766                            .bounds
 767                            .contains_point(self.window.mouse_position)
 768                        {
 769                            valid_regions.push(mouse_region.clone());
 770                        }
 771                    }
 772                }
 773
 774                _ => {
 775                    for (mouse_region, _) in self.window.mouse_regions.iter().rev() {
 776                        // Contains
 777                        if mouse_region
 778                            .bounds
 779                            .contains_point(self.window.mouse_position)
 780                        {
 781                            valid_regions.push(mouse_region.clone());
 782                        }
 783                    }
 784                }
 785            }
 786
 787            //3. Fire region events
 788            let hovered_region_ids = self.window.hovered_region_ids.clone();
 789            for valid_region in valid_regions.into_iter() {
 790                let mut handled = false;
 791                mouse_event.set_region(valid_region.bounds);
 792                if let MouseEvent::Hover(e) = &mut mouse_event {
 793                    e.started = hovered_region_ids.contains(&valid_region.id())
 794                }
 795                // Handle Down events if the MouseRegion has a Click or Drag handler. This makes the api more intuitive as you would
 796                // not expect a MouseRegion to be transparent to Down events if it also has a Click handler.
 797                // This behavior can be overridden by adding a Down handler
 798                if let MouseEvent::Down(e) = &mouse_event {
 799                    let has_click = valid_region
 800                        .handlers
 801                        .contains(MouseEvent::click_disc(), Some(e.button));
 802                    let has_drag = valid_region
 803                        .handlers
 804                        .contains(MouseEvent::drag_disc(), Some(e.button));
 805                    let has_down = valid_region
 806                        .handlers
 807                        .contains(MouseEvent::down_disc(), Some(e.button));
 808                    if !has_down && (has_click || has_drag) {
 809                        handled = true;
 810                    }
 811                }
 812
 813                // `event_consumed` should only be true if there are any handlers for this event.
 814                let mut event_consumed = handled;
 815                if let Some(callbacks) = valid_region.handlers.get(&mouse_event.handler_key()) {
 816                    for callback in callbacks {
 817                        handled = true;
 818                        let view_id = valid_region.id().view_id();
 819                        self.update_any_view(view_id, |view, cx| {
 820                            handled = callback(mouse_event.clone(), view.as_any_mut(), cx, view_id);
 821                        });
 822                        event_consumed |= handled;
 823                        any_event_handled |= handled;
 824                    }
 825                }
 826
 827                any_event_handled |= handled;
 828
 829                // For bubbling events, if the event was handled, don't continue dispatching.
 830                // This only makes sense for local events which return false from is_capturable.
 831                if event_consumed && mouse_event.is_capturable() {
 832                    break;
 833                }
 834            }
 835        }
 836
 837        for view_id in notified_views {
 838            self.notify_view(window_id, view_id);
 839        }
 840
 841        any_event_handled
 842    }
 843
 844    pub fn dispatch_key_down(&mut self, event: &KeyDownEvent) -> bool {
 845        let window_id = self.window_id;
 846        if let Some(focused_view_id) = self.window.focused_view_id {
 847            for view_id in self.ancestors(focused_view_id).collect::<Vec<_>>() {
 848                if let Some(mut view) = self.views.remove(&(window_id, view_id)) {
 849                    let handled = view.key_down(event, self, view_id);
 850                    self.views.insert((window_id, view_id), view);
 851                    if handled {
 852                        return true;
 853                    }
 854                } else {
 855                    log::error!("view {} does not exist", view_id)
 856                }
 857            }
 858        }
 859
 860        false
 861    }
 862
 863    pub fn dispatch_key_up(&mut self, event: &KeyUpEvent) -> bool {
 864        let window_id = self.window_id;
 865        if let Some(focused_view_id) = self.window.focused_view_id {
 866            for view_id in self.ancestors(focused_view_id).collect::<Vec<_>>() {
 867                if let Some(mut view) = self.views.remove(&(window_id, view_id)) {
 868                    let handled = view.key_up(event, self, view_id);
 869                    self.views.insert((window_id, view_id), view);
 870                    if handled {
 871                        return true;
 872                    }
 873                } else {
 874                    log::error!("view {} does not exist", view_id)
 875                }
 876            }
 877        }
 878
 879        false
 880    }
 881
 882    pub fn dispatch_modifiers_changed(&mut self, event: &ModifiersChangedEvent) -> bool {
 883        let window_id = self.window_id;
 884        if let Some(focused_view_id) = self.window.focused_view_id {
 885            for view_id in self.ancestors(focused_view_id).collect::<Vec<_>>() {
 886                if let Some(mut view) = self.views.remove(&(window_id, view_id)) {
 887                    let handled = view.modifiers_changed(event, self, view_id);
 888                    self.views.insert((window_id, view_id), view);
 889                    if handled {
 890                        return true;
 891                    }
 892                } else {
 893                    log::error!("view {} does not exist", view_id)
 894                }
 895            }
 896        }
 897
 898        false
 899    }
 900
 901    pub fn invalidate(&mut self, invalidation: &mut WindowInvalidation, appearance: Appearance) {
 902        self.start_frame();
 903        self.window.appearance = appearance;
 904        for view_id in &invalidation.removed {
 905            invalidation.updated.remove(view_id);
 906            self.window.rendered_views.remove(view_id);
 907        }
 908        for view_id in &invalidation.updated {
 909            let titlebar_height = self.window.titlebar_height;
 910            let hovered_region_ids = self.window.hovered_region_ids.clone();
 911            let clicked_region_ids = self
 912                .window
 913                .clicked_button
 914                .map(|button| (self.window.clicked_region_ids.clone(), button));
 915
 916            let element = self
 917                .render_view(RenderParams {
 918                    view_id: *view_id,
 919                    titlebar_height,
 920                    hovered_region_ids,
 921                    clicked_region_ids,
 922                    refreshing: false,
 923                    appearance,
 924                })
 925                .unwrap();
 926            self.window.rendered_views.insert(*view_id, element);
 927        }
 928    }
 929
 930    pub fn render_view(&mut self, params: RenderParams) -> Result<Box<dyn AnyRootElement>> {
 931        let window_id = self.window_id;
 932        let view_id = params.view_id;
 933        let mut view = self
 934            .views
 935            .remove(&(window_id, view_id))
 936            .ok_or_else(|| anyhow!("view not found"))?;
 937        let element = view.render(self, view_id);
 938        self.views.insert((window_id, view_id), view);
 939        Ok(element)
 940    }
 941
 942    pub fn build_scene(&mut self) -> Result<Scene> {
 943        let window_size = self.window.platform_window.content_size();
 944        let scale_factor = self.window.platform_window.scale_factor();
 945
 946        let root_view_id = self.window.root_view().id();
 947        let mut rendered_root = self.window.rendered_views.remove(&root_view_id).unwrap();
 948        rendered_root.layout(SizeConstraint::strict(window_size), self)?;
 949
 950        let mut scene_builder = SceneBuilder::new(scale_factor);
 951        rendered_root.paint(
 952            &mut scene_builder,
 953            Vector2F::zero(),
 954            RectF::from_points(Vector2F::zero(), window_size),
 955            self,
 956        )?;
 957        self.window
 958            .rendered_views
 959            .insert(root_view_id, rendered_root);
 960
 961        self.window.text_layout_cache.finish_frame();
 962        let scene = scene_builder.build();
 963        self.window.cursor_regions = scene.cursor_regions();
 964        self.window.mouse_regions = scene.mouse_regions();
 965
 966        if self.window_is_active() {
 967            if let Some(event) = self.window.last_mouse_moved_event.clone() {
 968                self.dispatch_event(event, true);
 969            }
 970        }
 971
 972        Ok(scene)
 973    }
 974
 975    pub fn rect_for_text_range(&self, range_utf16: Range<usize>) -> Option<RectF> {
 976        let root_view_id = self.window.root_view().id();
 977        self.window
 978            .rendered_views
 979            .get(&root_view_id)?
 980            .rect_for_text_range(range_utf16, self)
 981            .log_err()
 982            .flatten()
 983    }
 984
 985    pub fn debug_elements(&self) -> Option<json::Value> {
 986        let view = self.window.root_view();
 987        Some(json!({
 988            "root_view": view.debug_json(self),
 989            "root_element": self.window.rendered_views.get(&view.id())
 990                .and_then(|root_element| {
 991                    root_element.debug(self).log_err()
 992                })
 993        }))
 994    }
 995
 996    pub fn set_window_title(&mut self, title: &str) {
 997        self.window.platform_window.set_title(title);
 998    }
 999
1000    pub fn set_window_edited(&mut self, edited: bool) {
1001        self.window.platform_window.set_edited(edited);
1002    }
1003
1004    pub fn is_topmost_window_for_position(&self, position: Vector2F) -> bool {
1005        self.window
1006            .platform_window
1007            .is_topmost_for_position(position)
1008    }
1009
1010    pub fn activate_window(&self) {
1011        self.window.platform_window.activate();
1012    }
1013
1014    pub fn window_is_active(&self) -> bool {
1015        self.window.is_active
1016    }
1017
1018    pub fn window_is_fullscreen(&self) -> bool {
1019        self.window.is_fullscreen
1020    }
1021
1022    pub(crate) fn handle_dispatch_action_from_effect(
1023        &mut self,
1024        view_id: Option<usize>,
1025        action: &dyn Action,
1026    ) -> bool {
1027        if let Some(view_id) = view_id {
1028            self.halt_action_dispatch = false;
1029            self.visit_dispatch_path(view_id, |view_id, capture_phase, cx| {
1030                cx.update_any_view(view_id, |view, cx| {
1031                    let type_id = view.as_any().type_id();
1032                    if let Some((name, mut handlers)) = cx
1033                        .actions_mut(capture_phase)
1034                        .get_mut(&type_id)
1035                        .and_then(|h| h.remove_entry(&action.id()))
1036                    {
1037                        for handler in handlers.iter_mut().rev() {
1038                            cx.halt_action_dispatch = true;
1039                            handler(view, action, cx, view_id);
1040                            if cx.halt_action_dispatch {
1041                                break;
1042                            }
1043                        }
1044                        cx.actions_mut(capture_phase)
1045                            .get_mut(&type_id)
1046                            .unwrap()
1047                            .insert(name, handlers);
1048                    }
1049                });
1050
1051                !cx.halt_action_dispatch
1052            });
1053        }
1054
1055        if !self.halt_action_dispatch {
1056            self.halt_action_dispatch = self.dispatch_global_action_any(action);
1057        }
1058
1059        self.pending_effects
1060            .push_back(Effect::ActionDispatchNotification {
1061                action_id: action.id(),
1062            });
1063        self.halt_action_dispatch
1064    }
1065
1066    /// Returns an iterator over all of the view ids from the passed view up to the root of the window
1067    /// Includes the passed view itself
1068    pub(crate) fn ancestors(&self, mut view_id: usize) -> impl Iterator<Item = usize> + '_ {
1069        std::iter::once(view_id)
1070            .into_iter()
1071            .chain(std::iter::from_fn(move || {
1072                if let Some(ParentId::View(parent_id)) =
1073                    self.parents.get(&(self.window_id, view_id))
1074                {
1075                    view_id = *parent_id;
1076                    Some(view_id)
1077                } else {
1078                    None
1079                }
1080            }))
1081    }
1082
1083    /// Returns the id of the parent of the given view, or none if the given
1084    /// view is the root.
1085    pub(crate) fn parent(&self, view_id: usize) -> Option<usize> {
1086        if let Some(ParentId::View(view_id)) = self.parents.get(&(self.window_id, view_id)) {
1087            Some(*view_id)
1088        } else {
1089            None
1090        }
1091    }
1092
1093    // Traverses the parent tree. Walks down the tree toward the passed
1094    // view calling visit with true. Then walks back up the tree calling visit with false.
1095    // If `visit` returns false this function will immediately return.
1096    fn visit_dispatch_path(
1097        &mut self,
1098        view_id: usize,
1099        mut visit: impl FnMut(usize, bool, &mut WindowContext) -> bool,
1100    ) {
1101        // List of view ids from the leaf to the root of the window
1102        let path = self.ancestors(view_id).collect::<Vec<_>>();
1103
1104        // Walk down from the root to the leaf calling visit with capture_phase = true
1105        for view_id in path.iter().rev() {
1106            if !visit(*view_id, true, self) {
1107                return;
1108            }
1109        }
1110
1111        // Walk up from the leaf to the root calling visit with capture_phase = false
1112        for view_id in path.iter() {
1113            if !visit(*view_id, false, self) {
1114                return;
1115            }
1116        }
1117    }
1118
1119    pub fn focused_view_id(&self) -> Option<usize> {
1120        self.window.focused_view_id
1121    }
1122
1123    pub fn is_child_focused(&self, view: &AnyViewHandle) -> bool {
1124        if let Some(focused_view_id) = self.focused_view_id() {
1125            self.ancestors(focused_view_id)
1126                .skip(1) // Skip self id
1127                .any(|parent| parent == view.view_id)
1128        } else {
1129            false
1130        }
1131    }
1132
1133    pub fn window_bounds(&self) -> WindowBounds {
1134        self.window.platform_window.bounds()
1135    }
1136
1137    pub fn window_appearance(&self) -> Appearance {
1138        self.window.appearance
1139    }
1140
1141    pub fn window_display_uuid(&self) -> Option<Uuid> {
1142        self.window.platform_window.screen().display_uuid()
1143    }
1144
1145    pub fn show_character_palette(&self) {
1146        self.window.platform_window.show_character_palette();
1147    }
1148
1149    pub fn minimize_window(&self) {
1150        self.window.platform_window.minimize();
1151    }
1152
1153    pub fn zoom_window(&self) {
1154        self.window.platform_window.zoom();
1155    }
1156
1157    pub fn toggle_full_screen(&self) {
1158        self.window.platform_window.toggle_full_screen();
1159    }
1160
1161    pub fn prompt(
1162        &self,
1163        level: PromptLevel,
1164        msg: &str,
1165        answers: &[&str],
1166    ) -> oneshot::Receiver<usize> {
1167        self.window.platform_window.prompt(level, msg, answers)
1168    }
1169
1170    pub fn replace_root_view<V, F>(&mut self, build_root_view: F) -> ViewHandle<V>
1171    where
1172        V: View,
1173        F: FnOnce(&mut ViewContext<V>) -> V,
1174    {
1175        let root_view = self
1176            .build_and_insert_view(ParentId::Root, |cx| Some(build_root_view(cx)))
1177            .unwrap();
1178        self.window.root_view = Some(root_view.clone().into_any());
1179        self.window.focused_view_id = Some(root_view.id());
1180        root_view
1181    }
1182
1183    pub(crate) fn build_and_insert_view<T, F>(
1184        &mut self,
1185        parent_id: ParentId,
1186        build_view: F,
1187    ) -> Option<ViewHandle<T>>
1188    where
1189        T: View,
1190        F: FnOnce(&mut ViewContext<T>) -> Option<T>,
1191    {
1192        let window_id = self.window_id;
1193        let view_id = post_inc(&mut self.next_entity_id);
1194        // Make sure we can tell child views about their parentu
1195        self.parents.insert((window_id, view_id), parent_id);
1196        let mut cx = ViewContext::mutable(self, view_id);
1197        let handle = if let Some(view) = build_view(&mut cx) {
1198            self.views.insert((window_id, view_id), Box::new(view));
1199            self.window
1200                .invalidation
1201                .get_or_insert_with(Default::default)
1202                .updated
1203                .insert(view_id);
1204            Some(ViewHandle::new(window_id, view_id, &self.ref_counts))
1205        } else {
1206            self.parents.remove(&(window_id, view_id));
1207            None
1208        };
1209        handle
1210    }
1211}
1212
1213pub struct RenderParams {
1214    pub view_id: usize,
1215    pub titlebar_height: f32,
1216    pub hovered_region_ids: HashSet<MouseRegionId>,
1217    pub clicked_region_ids: Option<(HashSet<MouseRegionId>, MouseButton)>,
1218    pub refreshing: bool,
1219    pub appearance: Appearance,
1220}
1221
1222#[derive(Clone, Copy, Debug, Default, Eq, PartialEq)]
1223pub enum Axis {
1224    #[default]
1225    Horizontal,
1226    Vertical,
1227}
1228
1229impl Axis {
1230    pub fn invert(self) -> Self {
1231        match self {
1232            Self::Horizontal => Self::Vertical,
1233            Self::Vertical => Self::Horizontal,
1234        }
1235    }
1236
1237    pub fn component(&self, point: Vector2F) -> f32 {
1238        match self {
1239            Self::Horizontal => point.x(),
1240            Self::Vertical => point.y(),
1241        }
1242    }
1243}
1244
1245impl ToJson for Axis {
1246    fn to_json(&self) -> serde_json::Value {
1247        match self {
1248            Axis::Horizontal => json!("horizontal"),
1249            Axis::Vertical => json!("vertical"),
1250        }
1251    }
1252}
1253
1254impl StaticColumnCount for Axis {}
1255impl Bind for Axis {
1256    fn bind(&self, statement: &Statement, start_index: i32) -> anyhow::Result<i32> {
1257        match self {
1258            Axis::Horizontal => "Horizontal",
1259            Axis::Vertical => "Vertical",
1260        }
1261        .bind(statement, start_index)
1262    }
1263}
1264
1265impl Column for Axis {
1266    fn column(statement: &mut Statement, start_index: i32) -> anyhow::Result<(Self, i32)> {
1267        String::column(statement, start_index).and_then(|(axis_text, next_index)| {
1268            Ok((
1269                match axis_text.as_str() {
1270                    "Horizontal" => Axis::Horizontal,
1271                    "Vertical" => Axis::Vertical,
1272                    _ => bail!("Stored serialized item kind is incorrect"),
1273                },
1274                next_index,
1275            ))
1276        })
1277    }
1278}
1279
1280pub trait Vector2FExt {
1281    fn along(self, axis: Axis) -> f32;
1282}
1283
1284impl Vector2FExt for Vector2F {
1285    fn along(self, axis: Axis) -> f32 {
1286        match axis {
1287            Axis::Horizontal => self.x(),
1288            Axis::Vertical => self.y(),
1289        }
1290    }
1291}
1292
1293#[derive(Copy, Clone, Debug)]
1294pub struct SizeConstraint {
1295    pub min: Vector2F,
1296    pub max: Vector2F,
1297}
1298
1299impl SizeConstraint {
1300    pub fn new(min: Vector2F, max: Vector2F) -> Self {
1301        Self { min, max }
1302    }
1303
1304    pub fn strict(size: Vector2F) -> Self {
1305        Self {
1306            min: size,
1307            max: size,
1308        }
1309    }
1310
1311    pub fn strict_along(axis: Axis, max: f32) -> Self {
1312        match axis {
1313            Axis::Horizontal => Self {
1314                min: vec2f(max, 0.0),
1315                max: vec2f(max, f32::INFINITY),
1316            },
1317            Axis::Vertical => Self {
1318                min: vec2f(0.0, max),
1319                max: vec2f(f32::INFINITY, max),
1320            },
1321        }
1322    }
1323
1324    pub fn max_along(&self, axis: Axis) -> f32 {
1325        match axis {
1326            Axis::Horizontal => self.max.x(),
1327            Axis::Vertical => self.max.y(),
1328        }
1329    }
1330
1331    pub fn min_along(&self, axis: Axis) -> f32 {
1332        match axis {
1333            Axis::Horizontal => self.min.x(),
1334            Axis::Vertical => self.min.y(),
1335        }
1336    }
1337
1338    pub fn constrain(&self, size: Vector2F) -> Vector2F {
1339        vec2f(
1340            size.x().min(self.max.x()).max(self.min.x()),
1341            size.y().min(self.max.y()).max(self.min.y()),
1342        )
1343    }
1344}
1345
1346impl Default for SizeConstraint {
1347    fn default() -> Self {
1348        SizeConstraint {
1349            min: Vector2F::zero(),
1350            max: Vector2F::splat(f32::INFINITY),
1351        }
1352    }
1353}
1354
1355impl ToJson for SizeConstraint {
1356    fn to_json(&self) -> serde_json::Value {
1357        json!({
1358            "min": self.min.to_json(),
1359            "max": self.max.to_json(),
1360        })
1361    }
1362}
1363
1364pub struct ChildView {
1365    view_id: usize,
1366    view_name: &'static str,
1367}
1368
1369impl ChildView {
1370    pub fn new(view: &AnyViewHandle, cx: &AppContext) -> Self {
1371        let view_name = cx.view_ui_name(view.window_id(), view.id()).unwrap();
1372        Self {
1373            view_id: view.id(),
1374            view_name,
1375        }
1376    }
1377}
1378
1379impl<V: View> Drawable<V> for ChildView {
1380    type LayoutState = ();
1381    type PaintState = ();
1382
1383    fn layout(
1384        &mut self,
1385        constraint: SizeConstraint,
1386        _: &mut V,
1387        cx: &mut ViewContext<V>,
1388    ) -> (Vector2F, Self::LayoutState) {
1389        if let Some(mut rendered_view) = cx.window.rendered_views.remove(&self.view_id) {
1390            let size = rendered_view
1391                .layout(constraint, cx)
1392                .log_err()
1393                .unwrap_or(Vector2F::zero());
1394            cx.window.rendered_views.insert(self.view_id, rendered_view);
1395            (size, ())
1396        } else {
1397            log::error!(
1398                "layout called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1399                self.view_id,
1400                self.view_name
1401            );
1402            (Vector2F::zero(), ())
1403        }
1404    }
1405
1406    fn paint(
1407        &mut self,
1408        scene: &mut SceneBuilder,
1409        bounds: RectF,
1410        visible_bounds: RectF,
1411        _: &mut Self::LayoutState,
1412        _: &mut V,
1413        cx: &mut ViewContext<V>,
1414    ) {
1415        if let Some(mut rendered_view) = cx.window.rendered_views.remove(&self.view_id) {
1416            rendered_view
1417                .paint(scene, bounds.origin(), visible_bounds, cx)
1418                .log_err();
1419            cx.window.rendered_views.insert(self.view_id, rendered_view);
1420        } else {
1421            log::error!(
1422                "paint called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1423                self.view_id,
1424                self.view_name
1425            );
1426        }
1427    }
1428
1429    fn rect_for_text_range(
1430        &self,
1431        range_utf16: Range<usize>,
1432        _: RectF,
1433        _: RectF,
1434        _: &Self::LayoutState,
1435        _: &Self::PaintState,
1436        _: &V,
1437        cx: &ViewContext<V>,
1438    ) -> Option<RectF> {
1439        if let Some(rendered_view) = cx.window.rendered_views.get(&self.view_id) {
1440            rendered_view
1441                .rect_for_text_range(range_utf16, &cx.window_context)
1442                .log_err()
1443                .flatten()
1444        } else {
1445            log::error!(
1446                "rect_for_text_range called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1447                self.view_id,
1448                self.view_name
1449            );
1450            None
1451        }
1452    }
1453
1454    fn debug(
1455        &self,
1456        bounds: RectF,
1457        _: &Self::LayoutState,
1458        _: &Self::PaintState,
1459        _: &V,
1460        cx: &ViewContext<V>,
1461    ) -> serde_json::Value {
1462        json!({
1463            "type": "ChildView",
1464            "view_id": self.view_id,
1465            "bounds": bounds.to_json(),
1466            "view": if let Some(view) = cx.views.get(&(cx.window_id, self.view_id))  {
1467                view.debug_json(cx)
1468            } else {
1469                json!(null)
1470            },
1471            "child": if let Some(element) = cx.window.rendered_views.get(&self.view_id) {
1472                element.debug(&cx.window_context).log_err().unwrap_or_else(|| json!(null))
1473            } else {
1474                json!(null)
1475            }
1476        })
1477    }
1478}