window.rs

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