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, SceneBuilder, Subscription,
  18    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                    for (view_id, action) in matches {
 434                        if self.dispatch_action(Some(*view_id), action.as_ref()) {
 435                            self.keystroke_matcher.clear_pending();
 436                            handled_by = Some(action.boxed_clone());
 437                            break;
 438                        }
 439                    }
 440                    handled_by.is_some()
 441                }
 442            };
 443
 444            self.keystroke(
 445                window_id,
 446                keystroke.clone(),
 447                handled_by,
 448                match_result.clone(),
 449            );
 450            keystroke_handled
 451        } else {
 452            self.keystroke(window_id, keystroke.clone(), None, MatchResult::None);
 453            false
 454        }
 455    }
 456
 457    pub(crate) fn dispatch_event(&mut self, event: Event, event_reused: bool) -> bool {
 458        let mut mouse_events = SmallVec::<[_; 2]>::new();
 459        let mut notified_views: HashSet<usize> = Default::default();
 460        let window_id = self.window_id;
 461
 462        // 1. Handle platform event. Keyboard events get dispatched immediately, while mouse events
 463        //    get mapped into the mouse-specific MouseEvent type.
 464        //  -> These are usually small: [Mouse Down] or [Mouse up, Click] or [Mouse Moved, Mouse Dragged?]
 465        //  -> Also updates mouse-related state
 466        match &event {
 467            Event::KeyDown(e) => return self.dispatch_key_down(e),
 468
 469            Event::KeyUp(e) => return self.dispatch_key_up(e),
 470
 471            Event::ModifiersChanged(e) => return self.dispatch_modifiers_changed(e),
 472
 473            Event::MouseDown(e) => {
 474                // Click events are weird because they can be fired after a drag event.
 475                // MDN says that browsers handle this by starting from 'the most
 476                // specific ancestor element that contained both [positions]'
 477                // So we need to store the overlapping regions on mouse down.
 478
 479                // If there is already region being clicked, don't replace it.
 480                if self.window.clicked_region.is_none() {
 481                    self.window.clicked_region_ids = self
 482                        .window
 483                        .mouse_regions
 484                        .iter()
 485                        .filter_map(|(region, _)| {
 486                            if region.bounds.contains_point(e.position) {
 487                                Some(region.id())
 488                            } else {
 489                                None
 490                            }
 491                        })
 492                        .collect();
 493
 494                    let mut highest_z_index = 0;
 495                    let mut clicked_region_id = None;
 496                    for (region, z_index) in self.window.mouse_regions.iter() {
 497                        if region.bounds.contains_point(e.position) && *z_index >= highest_z_index {
 498                            highest_z_index = *z_index;
 499                            clicked_region_id = Some(region.id());
 500                        }
 501                    }
 502
 503                    self.window.clicked_region =
 504                        clicked_region_id.map(|region_id| (region_id, e.button));
 505                }
 506
 507                mouse_events.push(MouseEvent::Down(MouseDown {
 508                    region: Default::default(),
 509                    platform_event: e.clone(),
 510                }));
 511                mouse_events.push(MouseEvent::DownOut(MouseDownOut {
 512                    region: Default::default(),
 513                    platform_event: e.clone(),
 514                }));
 515            }
 516
 517            Event::MouseUp(e) => {
 518                // NOTE: The order of event pushes is important! MouseUp events MUST be fired
 519                // before click events, and so the MouseUp events need to be pushed before
 520                // MouseClick events.
 521                mouse_events.push(MouseEvent::Up(MouseUp {
 522                    region: Default::default(),
 523                    platform_event: e.clone(),
 524                }));
 525                mouse_events.push(MouseEvent::UpOut(MouseUpOut {
 526                    region: Default::default(),
 527                    platform_event: e.clone(),
 528                }));
 529                mouse_events.push(MouseEvent::Click(MouseClick {
 530                    region: Default::default(),
 531                    platform_event: e.clone(),
 532                }));
 533                mouse_events.push(MouseEvent::ClickOut(MouseClickOut {
 534                    region: Default::default(),
 535                    platform_event: e.clone(),
 536                }));
 537            }
 538
 539            Event::MouseMoved(
 540                e @ MouseMovedEvent {
 541                    position,
 542                    pressed_button,
 543                    ..
 544                },
 545            ) => {
 546                let mut style_to_assign = CursorStyle::Arrow;
 547                for region in self.window.cursor_regions.iter().rev() {
 548                    if region.bounds.contains_point(*position) {
 549                        style_to_assign = region.style;
 550                        break;
 551                    }
 552                }
 553
 554                if self
 555                    .window
 556                    .platform_window
 557                    .is_topmost_for_position(*position)
 558                {
 559                    self.platform().set_cursor_style(style_to_assign);
 560                }
 561
 562                if !event_reused {
 563                    if pressed_button.is_some() {
 564                        mouse_events.push(MouseEvent::Drag(MouseDrag {
 565                            region: Default::default(),
 566                            prev_mouse_position: self.window.mouse_position,
 567                            platform_event: e.clone(),
 568                        }));
 569                    } else if let Some((_, clicked_button)) = self.window.clicked_region {
 570                        // Mouse up event happened outside the current window. Simulate mouse up button event
 571                        let button_event = e.to_button_event(clicked_button);
 572                        mouse_events.push(MouseEvent::Up(MouseUp {
 573                            region: Default::default(),
 574                            platform_event: button_event.clone(),
 575                        }));
 576                        mouse_events.push(MouseEvent::UpOut(MouseUpOut {
 577                            region: Default::default(),
 578                            platform_event: button_event.clone(),
 579                        }));
 580                        mouse_events.push(MouseEvent::Click(MouseClick {
 581                            region: Default::default(),
 582                            platform_event: button_event.clone(),
 583                        }));
 584                    }
 585
 586                    mouse_events.push(MouseEvent::Move(MouseMove {
 587                        region: Default::default(),
 588                        platform_event: e.clone(),
 589                    }));
 590                }
 591
 592                mouse_events.push(MouseEvent::Hover(MouseHover {
 593                    region: Default::default(),
 594                    platform_event: e.clone(),
 595                    started: false,
 596                }));
 597                mouse_events.push(MouseEvent::MoveOut(MouseMoveOut {
 598                    region: Default::default(),
 599                }));
 600
 601                self.window.last_mouse_moved_event = Some(event.clone());
 602            }
 603
 604            Event::MouseExited(event) => {
 605                // When the platform sends a MouseExited event, synthesize
 606                // a MouseMoved event whose position is outside the window's
 607                // bounds so that hover and cursor state can be updated.
 608                return self.dispatch_event(
 609                    Event::MouseMoved(MouseMovedEvent {
 610                        position: event.position,
 611                        pressed_button: event.pressed_button,
 612                        modifiers: event.modifiers,
 613                    }),
 614                    event_reused,
 615                );
 616            }
 617
 618            Event::ScrollWheel(e) => mouse_events.push(MouseEvent::ScrollWheel(MouseScrollWheel {
 619                region: Default::default(),
 620                platform_event: e.clone(),
 621            })),
 622        }
 623
 624        if let Some(position) = event.position() {
 625            self.window.mouse_position = position;
 626        }
 627
 628        // 2. Dispatch mouse events on regions
 629        let mut any_event_handled = false;
 630        for mut mouse_event in mouse_events {
 631            let mut valid_regions = Vec::new();
 632
 633            // GPUI elements are arranged by z_index but sibling elements can register overlapping
 634            // mouse regions. As such, hover events are only fired on overlapping elements which
 635            // are at the same z-index as the topmost element which overlaps with the mouse.
 636            match &mouse_event {
 637                MouseEvent::Hover(_) => {
 638                    let mut highest_z_index = None;
 639                    let mouse_position = self.window.mouse_position.clone();
 640                    let window = &mut *self.window;
 641                    for (region, z_index) in window.mouse_regions.iter().rev() {
 642                        // Allow mouse regions to appear transparent to hovers
 643                        if !region.hoverable {
 644                            continue;
 645                        }
 646
 647                        let contains_mouse = region.bounds.contains_point(mouse_position);
 648
 649                        if contains_mouse && highest_z_index.is_none() {
 650                            highest_z_index = Some(z_index);
 651                        }
 652
 653                        // This unwrap relies on short circuiting boolean expressions
 654                        // The right side of the && is only executed when contains_mouse
 655                        // is true, and we know above that when contains_mouse is true
 656                        // highest_z_index is set.
 657                        if contains_mouse && z_index == highest_z_index.unwrap() {
 658                            //Ensure that hover entrance events aren't sent twice
 659                            if window.hovered_region_ids.insert(region.id()) {
 660                                valid_regions.push(region.clone());
 661                                if region.notify_on_hover {
 662                                    notified_views.insert(region.id().view_id());
 663                                }
 664                            }
 665                        } else {
 666                            // Ensure that hover exit events aren't sent twice
 667                            if window.hovered_region_ids.remove(&region.id()) {
 668                                valid_regions.push(region.clone());
 669                                if region.notify_on_hover {
 670                                    notified_views.insert(region.id().view_id());
 671                                }
 672                            }
 673                        }
 674                    }
 675                }
 676
 677                MouseEvent::Down(_) | MouseEvent::Up(_) => {
 678                    for (region, _) in self.window.mouse_regions.iter().rev() {
 679                        if region.bounds.contains_point(self.window.mouse_position) {
 680                            valid_regions.push(region.clone());
 681                            if region.notify_on_click {
 682                                notified_views.insert(region.id().view_id());
 683                            }
 684                        }
 685                    }
 686                }
 687
 688                MouseEvent::Click(e) => {
 689                    // Only raise click events if the released button is the same as the one stored
 690                    if self
 691                        .window
 692                        .clicked_region
 693                        .map(|(_, clicked_button)| clicked_button == e.button)
 694                        .unwrap_or(false)
 695                    {
 696                        // Clear clicked regions and clicked button
 697                        let clicked_region_ids = std::mem::replace(
 698                            &mut self.window.clicked_region_ids,
 699                            Default::default(),
 700                        );
 701                        self.window.clicked_region = None;
 702
 703                        // Find regions which still overlap with the mouse since the last MouseDown happened
 704                        for (mouse_region, _) in self.window.mouse_regions.iter().rev() {
 705                            if clicked_region_ids.contains(&mouse_region.id()) {
 706                                if mouse_region
 707                                    .bounds
 708                                    .contains_point(self.window.mouse_position)
 709                                {
 710                                    valid_regions.push(mouse_region.clone());
 711                                }
 712                            }
 713                        }
 714                    }
 715                }
 716
 717                MouseEvent::Drag(_) => {
 718                    for (mouse_region, _) in self.window.mouse_regions.iter().rev() {
 719                        if self.window.clicked_region_ids.contains(&mouse_region.id()) {
 720                            valid_regions.push(mouse_region.clone());
 721                        }
 722                    }
 723                }
 724
 725                MouseEvent::MoveOut(_)
 726                | MouseEvent::UpOut(_)
 727                | MouseEvent::DownOut(_)
 728                | MouseEvent::ClickOut(_) => {
 729                    for (mouse_region, _) in self.window.mouse_regions.iter().rev() {
 730                        // NOT contains
 731                        if !mouse_region
 732                            .bounds
 733                            .contains_point(self.window.mouse_position)
 734                        {
 735                            valid_regions.push(mouse_region.clone());
 736                        }
 737                    }
 738                }
 739
 740                _ => {
 741                    for (mouse_region, _) in self.window.mouse_regions.iter().rev() {
 742                        // Contains
 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            //3. Fire region events
 754            let hovered_region_ids = self.window.hovered_region_ids.clone();
 755            for valid_region in valid_regions.into_iter() {
 756                let mut handled = false;
 757                mouse_event.set_region(valid_region.bounds);
 758                if let MouseEvent::Hover(e) = &mut mouse_event {
 759                    e.started = hovered_region_ids.contains(&valid_region.id())
 760                }
 761                // Handle Down events if the MouseRegion has a Click or Drag handler. This makes the api more intuitive as you would
 762                // not expect a MouseRegion to be transparent to Down events if it also has a Click handler.
 763                // This behavior can be overridden by adding a Down handler
 764                if let MouseEvent::Down(e) = &mouse_event {
 765                    let has_click = valid_region
 766                        .handlers
 767                        .contains(MouseEvent::click_disc(), Some(e.button));
 768                    let has_drag = valid_region
 769                        .handlers
 770                        .contains(MouseEvent::drag_disc(), Some(e.button));
 771                    let has_down = valid_region
 772                        .handlers
 773                        .contains(MouseEvent::down_disc(), Some(e.button));
 774                    if !has_down && (has_click || has_drag) {
 775                        handled = true;
 776                    }
 777                }
 778
 779                // `event_consumed` should only be true if there are any handlers for this event.
 780                let mut event_consumed = handled;
 781                if let Some(callbacks) = valid_region.handlers.get(&mouse_event.handler_key()) {
 782                    for callback in callbacks {
 783                        handled = true;
 784                        let view_id = valid_region.id().view_id();
 785                        self.update_any_view(view_id, |view, cx| {
 786                            handled = callback(mouse_event.clone(), view.as_any_mut(), cx, view_id);
 787                        });
 788                        event_consumed |= handled;
 789                        any_event_handled |= handled;
 790                    }
 791                }
 792
 793                any_event_handled |= handled;
 794
 795                // For bubbling events, if the event was handled, don't continue dispatching.
 796                // This only makes sense for local events which return false from is_capturable.
 797                if event_consumed && mouse_event.is_capturable() {
 798                    break;
 799                }
 800            }
 801        }
 802
 803        for view_id in notified_views {
 804            self.notify_view(window_id, view_id);
 805        }
 806
 807        any_event_handled
 808    }
 809
 810    pub(crate) fn dispatch_key_down(&mut self, event: &KeyDownEvent) -> bool {
 811        let window_id = self.window_id;
 812        if let Some(focused_view_id) = self.window.focused_view_id {
 813            for view_id in self.ancestors(focused_view_id).collect::<Vec<_>>() {
 814                if let Some(mut view) = self.views.remove(&(window_id, view_id)) {
 815                    let handled = view.key_down(event, self, view_id);
 816                    self.views.insert((window_id, view_id), view);
 817                    if handled {
 818                        return true;
 819                    }
 820                } else {
 821                    log::error!("view {} does not exist", view_id)
 822                }
 823            }
 824        }
 825
 826        false
 827    }
 828
 829    pub(crate) fn dispatch_key_up(&mut self, event: &KeyUpEvent) -> bool {
 830        let window_id = self.window_id;
 831        if let Some(focused_view_id) = self.window.focused_view_id {
 832            for view_id in self.ancestors(focused_view_id).collect::<Vec<_>>() {
 833                if let Some(mut view) = self.views.remove(&(window_id, view_id)) {
 834                    let handled = view.key_up(event, self, view_id);
 835                    self.views.insert((window_id, view_id), view);
 836                    if handled {
 837                        return true;
 838                    }
 839                } else {
 840                    log::error!("view {} does not exist", view_id)
 841                }
 842            }
 843        }
 844
 845        false
 846    }
 847
 848    pub(crate) fn dispatch_modifiers_changed(&mut self, event: &ModifiersChangedEvent) -> bool {
 849        let window_id = self.window_id;
 850        if let Some(focused_view_id) = self.window.focused_view_id {
 851            for view_id in self.ancestors(focused_view_id).collect::<Vec<_>>() {
 852                if let Some(mut view) = self.views.remove(&(window_id, view_id)) {
 853                    let handled = view.modifiers_changed(event, self, view_id);
 854                    self.views.insert((window_id, view_id), view);
 855                    if handled {
 856                        return true;
 857                    }
 858                } else {
 859                    log::error!("view {} does not exist", view_id)
 860                }
 861            }
 862        }
 863
 864        false
 865    }
 866
 867    pub fn invalidate(&mut self, mut invalidation: WindowInvalidation, appearance: Appearance) {
 868        self.start_frame();
 869        self.window.appearance = appearance;
 870        for view_id in &invalidation.removed {
 871            invalidation.updated.remove(view_id);
 872            self.window.rendered_views.remove(view_id);
 873        }
 874        for view_id in &invalidation.updated {
 875            let titlebar_height = self.window.titlebar_height;
 876            let element = self
 877                .render_view(RenderParams {
 878                    view_id: *view_id,
 879                    titlebar_height,
 880                    refreshing: false,
 881                    appearance,
 882                })
 883                .unwrap();
 884            self.window.rendered_views.insert(*view_id, element);
 885        }
 886    }
 887
 888    pub fn render_view(&mut self, params: RenderParams) -> Result<Box<dyn AnyRootElement>> {
 889        let window_id = self.window_id;
 890        let view_id = params.view_id;
 891        let mut view = self
 892            .views
 893            .remove(&(window_id, view_id))
 894            .ok_or_else(|| anyhow!("view not found"))?;
 895        let element = view.render(self, view_id);
 896        self.views.insert((window_id, view_id), view);
 897        Ok(element)
 898    }
 899
 900    pub(crate) fn layout(&mut self, refreshing: bool) -> Result<HashMap<usize, usize>> {
 901        let window_size = self.window.platform_window.content_size();
 902        let root_view_id = self.window.root_view().id();
 903        let mut rendered_root = self.window.rendered_views.remove(&root_view_id).unwrap();
 904        let mut new_parents = HashMap::default();
 905        let mut views_to_notify_if_ancestors_change = HashMap::default();
 906        rendered_root.layout(
 907            SizeConstraint::strict(window_size),
 908            &mut new_parents,
 909            &mut views_to_notify_if_ancestors_change,
 910            refreshing,
 911            self,
 912        )?;
 913
 914        for (view_id, view_ids_to_notify) in views_to_notify_if_ancestors_change {
 915            let mut current_view_id = view_id;
 916            loop {
 917                let old_parent_id = self.window.parents.get(&current_view_id);
 918                let new_parent_id = new_parents.get(&current_view_id);
 919                if old_parent_id.is_none() && new_parent_id.is_none() {
 920                    break;
 921                } else if old_parent_id == new_parent_id {
 922                    current_view_id = *old_parent_id.unwrap();
 923                } else {
 924                    let window_id = self.window_id;
 925                    for view_id_to_notify in view_ids_to_notify {
 926                        self.notify_view(window_id, view_id_to_notify);
 927                    }
 928                    break;
 929                }
 930            }
 931        }
 932
 933        let old_parents = mem::replace(&mut self.window.parents, new_parents);
 934        self.window
 935            .rendered_views
 936            .insert(root_view_id, rendered_root);
 937        Ok(old_parents)
 938    }
 939
 940    pub(crate) fn paint(&mut self) -> Result<Scene> {
 941        let window_size = self.window.platform_window.content_size();
 942        let scale_factor = self.window.platform_window.scale_factor();
 943
 944        let root_view_id = self.window.root_view().id();
 945        let mut rendered_root = self.window.rendered_views.remove(&root_view_id).unwrap();
 946
 947        let mut scene_builder = SceneBuilder::new(scale_factor);
 948        rendered_root.paint(
 949            &mut scene_builder,
 950            Vector2F::zero(),
 951            RectF::from_points(Vector2F::zero(), window_size),
 952            self,
 953        )?;
 954        self.window
 955            .rendered_views
 956            .insert(root_view_id, rendered_root);
 957
 958        self.window.text_layout_cache.finish_frame();
 959        let scene = scene_builder.build();
 960        self.window.cursor_regions = scene.cursor_regions();
 961        self.window.mouse_regions = scene.mouse_regions();
 962
 963        if self.window_is_active() {
 964            if let Some(event) = self.window.last_mouse_moved_event.clone() {
 965                self.dispatch_event(event, true);
 966            }
 967        }
 968
 969        Ok(scene)
 970    }
 971
 972    pub fn rect_for_text_range(&self, range_utf16: Range<usize>) -> Option<RectF> {
 973        let focused_view_id = self.window.focused_view_id?;
 974        self.window
 975            .rendered_views
 976            .get(&focused_view_id)?
 977            .rect_for_text_range(range_utf16, self)
 978            .log_err()
 979            .flatten()
 980    }
 981
 982    pub fn set_window_title(&mut self, title: &str) {
 983        self.window.platform_window.set_title(title);
 984    }
 985
 986    pub fn set_window_edited(&mut self, edited: bool) {
 987        self.window.platform_window.set_edited(edited);
 988    }
 989
 990    pub fn is_topmost_window_for_position(&self, position: Vector2F) -> bool {
 991        self.window
 992            .platform_window
 993            .is_topmost_for_position(position)
 994    }
 995
 996    pub fn activate_window(&self) {
 997        self.window.platform_window.activate();
 998    }
 999
1000    pub fn window_is_active(&self) -> bool {
1001        self.window.is_active
1002    }
1003
1004    pub fn window_is_fullscreen(&self) -> bool {
1005        self.window.is_fullscreen
1006    }
1007
1008    pub(crate) fn dispatch_action(&mut self, view_id: Option<usize>, action: &dyn Action) -> bool {
1009        if let Some(view_id) = view_id {
1010            self.halt_action_dispatch = false;
1011            self.visit_dispatch_path(view_id, |view_id, capture_phase, cx| {
1012                cx.update_any_view(view_id, |view, cx| {
1013                    let type_id = view.as_any().type_id();
1014                    if let Some((name, mut handlers)) = cx
1015                        .actions_mut(capture_phase)
1016                        .get_mut(&type_id)
1017                        .and_then(|h| h.remove_entry(&action.id()))
1018                    {
1019                        for handler in handlers.iter_mut().rev() {
1020                            cx.halt_action_dispatch = true;
1021                            handler(view, action, cx, view_id);
1022                            if cx.halt_action_dispatch {
1023                                break;
1024                            }
1025                        }
1026                        cx.actions_mut(capture_phase)
1027                            .get_mut(&type_id)
1028                            .unwrap()
1029                            .insert(name, handlers);
1030                    }
1031                });
1032
1033                !cx.halt_action_dispatch
1034            });
1035        }
1036
1037        if !self.halt_action_dispatch {
1038            self.halt_action_dispatch = self.dispatch_global_action_any(action);
1039        }
1040
1041        self.pending_effects
1042            .push_back(Effect::ActionDispatchNotification {
1043                action_id: action.id(),
1044            });
1045        self.halt_action_dispatch
1046    }
1047
1048    /// Returns an iterator over all of the view ids from the passed view up to the root of the window
1049    /// Includes the passed view itself
1050    pub(crate) fn ancestors(&self, mut view_id: usize) -> impl Iterator<Item = usize> + '_ {
1051        std::iter::once(view_id)
1052            .into_iter()
1053            .chain(std::iter::from_fn(move || {
1054                if let Some(parent_id) = self.window.parents.get(&view_id) {
1055                    view_id = *parent_id;
1056                    Some(view_id)
1057                } else {
1058                    None
1059                }
1060            }))
1061    }
1062
1063    // Traverses the parent tree. Walks down the tree toward the passed
1064    // view calling visit with true. Then walks back up the tree calling visit with false.
1065    // If `visit` returns false this function will immediately return.
1066    fn visit_dispatch_path(
1067        &mut self,
1068        view_id: usize,
1069        mut visit: impl FnMut(usize, bool, &mut WindowContext) -> bool,
1070    ) {
1071        // List of view ids from the leaf to the root of the window
1072        let path = self.ancestors(view_id).collect::<Vec<_>>();
1073
1074        // Walk down from the root to the leaf calling visit with capture_phase = true
1075        for view_id in path.iter().rev() {
1076            if !visit(*view_id, true, self) {
1077                return;
1078            }
1079        }
1080
1081        // Walk up from the leaf to the root calling visit with capture_phase = false
1082        for view_id in path.iter() {
1083            if !visit(*view_id, false, self) {
1084                return;
1085            }
1086        }
1087    }
1088
1089    pub fn focused_view_id(&self) -> Option<usize> {
1090        self.window.focused_view_id
1091    }
1092
1093    pub fn focus(&mut self, view_id: Option<usize>) {
1094        self.app_context.focus(self.window_id, view_id);
1095    }
1096
1097    pub fn window_bounds(&self) -> WindowBounds {
1098        self.window.platform_window.bounds()
1099    }
1100
1101    pub fn window_appearance(&self) -> Appearance {
1102        self.window.appearance
1103    }
1104
1105    pub fn window_display_uuid(&self) -> Option<Uuid> {
1106        self.window.platform_window.screen().display_uuid()
1107    }
1108
1109    pub fn show_character_palette(&self) {
1110        self.window.platform_window.show_character_palette();
1111    }
1112
1113    pub fn minimize_window(&self) {
1114        self.window.platform_window.minimize();
1115    }
1116
1117    pub fn zoom_window(&self) {
1118        self.window.platform_window.zoom();
1119    }
1120
1121    pub fn toggle_full_screen(&self) {
1122        self.window.platform_window.toggle_full_screen();
1123    }
1124
1125    pub fn prompt(
1126        &self,
1127        level: PromptLevel,
1128        msg: &str,
1129        answers: &[&str],
1130    ) -> oneshot::Receiver<usize> {
1131        self.window.platform_window.prompt(level, msg, answers)
1132    }
1133
1134    pub fn replace_root_view<V, F>(&mut self, build_root_view: F) -> ViewHandle<V>
1135    where
1136        V: View,
1137        F: FnOnce(&mut ViewContext<V>) -> V,
1138    {
1139        let root_view = self.add_view(|cx| build_root_view(cx));
1140        self.window.root_view = Some(root_view.clone().into_any());
1141        self.window.focused_view_id = Some(root_view.id());
1142        root_view
1143    }
1144
1145    pub fn add_view<T, F>(&mut self, build_view: F) -> ViewHandle<T>
1146    where
1147        T: View,
1148        F: FnOnce(&mut ViewContext<T>) -> T,
1149    {
1150        self.add_option_view(|cx| Some(build_view(cx))).unwrap()
1151    }
1152
1153    pub fn add_option_view<T, F>(&mut self, build_view: F) -> Option<ViewHandle<T>>
1154    where
1155        T: View,
1156        F: FnOnce(&mut ViewContext<T>) -> Option<T>,
1157    {
1158        let window_id = self.window_id;
1159        let view_id = post_inc(&mut self.next_entity_id);
1160        let mut cx = ViewContext::mutable(self, view_id);
1161        let handle = if let Some(view) = build_view(&mut cx) {
1162            let mut keymap_context = KeymapContext::default();
1163            view.update_keymap_context(&mut keymap_context, cx.app_context());
1164            self.views_metadata.insert(
1165                (window_id, view_id),
1166                ViewMetadata {
1167                    type_id: TypeId::of::<T>(),
1168                    keymap_context,
1169                },
1170            );
1171            self.views.insert((window_id, view_id), Box::new(view));
1172            self.window
1173                .invalidation
1174                .get_or_insert_with(Default::default)
1175                .updated
1176                .insert(view_id);
1177            Some(ViewHandle::new(window_id, view_id, &self.ref_counts))
1178        } else {
1179            None
1180        };
1181        handle
1182    }
1183}
1184
1185pub struct RenderParams {
1186    pub view_id: usize,
1187    pub titlebar_height: f32,
1188    pub refreshing: bool,
1189    pub appearance: Appearance,
1190}
1191
1192#[derive(Clone, Copy, Debug, Default, Eq, PartialEq)]
1193pub enum Axis {
1194    #[default]
1195    Horizontal,
1196    Vertical,
1197}
1198
1199impl Axis {
1200    pub fn invert(self) -> Self {
1201        match self {
1202            Self::Horizontal => Self::Vertical,
1203            Self::Vertical => Self::Horizontal,
1204        }
1205    }
1206
1207    pub fn component(&self, point: Vector2F) -> f32 {
1208        match self {
1209            Self::Horizontal => point.x(),
1210            Self::Vertical => point.y(),
1211        }
1212    }
1213}
1214
1215impl ToJson for Axis {
1216    fn to_json(&self) -> serde_json::Value {
1217        match self {
1218            Axis::Horizontal => json!("horizontal"),
1219            Axis::Vertical => json!("vertical"),
1220        }
1221    }
1222}
1223
1224impl StaticColumnCount for Axis {}
1225impl Bind for Axis {
1226    fn bind(&self, statement: &Statement, start_index: i32) -> anyhow::Result<i32> {
1227        match self {
1228            Axis::Horizontal => "Horizontal",
1229            Axis::Vertical => "Vertical",
1230        }
1231        .bind(statement, start_index)
1232    }
1233}
1234
1235impl Column for Axis {
1236    fn column(statement: &mut Statement, start_index: i32) -> anyhow::Result<(Self, i32)> {
1237        String::column(statement, start_index).and_then(|(axis_text, next_index)| {
1238            Ok((
1239                match axis_text.as_str() {
1240                    "Horizontal" => Axis::Horizontal,
1241                    "Vertical" => Axis::Vertical,
1242                    _ => bail!("Stored serialized item kind is incorrect"),
1243                },
1244                next_index,
1245            ))
1246        })
1247    }
1248}
1249
1250pub trait Vector2FExt {
1251    fn along(self, axis: Axis) -> f32;
1252}
1253
1254impl Vector2FExt for Vector2F {
1255    fn along(self, axis: Axis) -> f32 {
1256        match axis {
1257            Axis::Horizontal => self.x(),
1258            Axis::Vertical => self.y(),
1259        }
1260    }
1261}
1262
1263#[derive(Copy, Clone, Debug)]
1264pub struct SizeConstraint {
1265    pub min: Vector2F,
1266    pub max: Vector2F,
1267}
1268
1269impl SizeConstraint {
1270    pub fn new(min: Vector2F, max: Vector2F) -> Self {
1271        Self { min, max }
1272    }
1273
1274    pub fn strict(size: Vector2F) -> Self {
1275        Self {
1276            min: size,
1277            max: size,
1278        }
1279    }
1280
1281    pub fn strict_along(axis: Axis, max: f32) -> Self {
1282        match axis {
1283            Axis::Horizontal => Self {
1284                min: vec2f(max, 0.0),
1285                max: vec2f(max, f32::INFINITY),
1286            },
1287            Axis::Vertical => Self {
1288                min: vec2f(0.0, max),
1289                max: vec2f(f32::INFINITY, max),
1290            },
1291        }
1292    }
1293
1294    pub fn max_along(&self, axis: Axis) -> f32 {
1295        match axis {
1296            Axis::Horizontal => self.max.x(),
1297            Axis::Vertical => self.max.y(),
1298        }
1299    }
1300
1301    pub fn min_along(&self, axis: Axis) -> f32 {
1302        match axis {
1303            Axis::Horizontal => self.min.x(),
1304            Axis::Vertical => self.min.y(),
1305        }
1306    }
1307
1308    pub fn constrain(&self, size: Vector2F) -> Vector2F {
1309        vec2f(
1310            size.x().min(self.max.x()).max(self.min.x()),
1311            size.y().min(self.max.y()).max(self.min.y()),
1312        )
1313    }
1314}
1315
1316impl Default for SizeConstraint {
1317    fn default() -> Self {
1318        SizeConstraint {
1319            min: Vector2F::zero(),
1320            max: Vector2F::splat(f32::INFINITY),
1321        }
1322    }
1323}
1324
1325impl ToJson for SizeConstraint {
1326    fn to_json(&self) -> serde_json::Value {
1327        json!({
1328            "min": self.min.to_json(),
1329            "max": self.max.to_json(),
1330        })
1331    }
1332}
1333
1334pub struct ChildView {
1335    view_id: usize,
1336    view_name: &'static str,
1337}
1338
1339impl ChildView {
1340    pub fn new(view: &AnyViewHandle, cx: &AppContext) -> Self {
1341        let view_name = cx.view_ui_name(view.window_id(), view.id()).unwrap();
1342        Self {
1343            view_id: view.id(),
1344            view_name,
1345        }
1346    }
1347}
1348
1349impl<V: View> Element<V> for ChildView {
1350    type LayoutState = ();
1351    type PaintState = ();
1352
1353    fn layout(
1354        &mut self,
1355        constraint: SizeConstraint,
1356        _: &mut V,
1357        cx: &mut LayoutContext<V>,
1358    ) -> (Vector2F, Self::LayoutState) {
1359        if let Some(mut rendered_view) = cx.window.rendered_views.remove(&self.view_id) {
1360            cx.new_parents.insert(self.view_id, cx.view_id());
1361            let size = rendered_view
1362                .layout(
1363                    constraint,
1364                    cx.new_parents,
1365                    cx.views_to_notify_if_ancestors_change,
1366                    cx.refreshing,
1367                    cx.view_context,
1368                )
1369                .log_err()
1370                .unwrap_or(Vector2F::zero());
1371            cx.window.rendered_views.insert(self.view_id, rendered_view);
1372            (size, ())
1373        } else {
1374            log::error!(
1375                "layout called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1376                self.view_id,
1377                self.view_name
1378            );
1379            (Vector2F::zero(), ())
1380        }
1381    }
1382
1383    fn paint(
1384        &mut self,
1385        scene: &mut SceneBuilder,
1386        bounds: RectF,
1387        visible_bounds: RectF,
1388        _: &mut Self::LayoutState,
1389        _: &mut V,
1390        cx: &mut ViewContext<V>,
1391    ) {
1392        if let Some(mut rendered_view) = cx.window.rendered_views.remove(&self.view_id) {
1393            rendered_view
1394                .paint(scene, bounds.origin(), visible_bounds, cx)
1395                .log_err();
1396            cx.window.rendered_views.insert(self.view_id, rendered_view);
1397        } else {
1398            log::error!(
1399                "paint called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1400                self.view_id,
1401                self.view_name
1402            );
1403        }
1404    }
1405
1406    fn rect_for_text_range(
1407        &self,
1408        range_utf16: Range<usize>,
1409        _: RectF,
1410        _: RectF,
1411        _: &Self::LayoutState,
1412        _: &Self::PaintState,
1413        _: &V,
1414        cx: &ViewContext<V>,
1415    ) -> Option<RectF> {
1416        if let Some(rendered_view) = cx.window.rendered_views.get(&self.view_id) {
1417            rendered_view
1418                .rect_for_text_range(range_utf16, &cx.window_context)
1419                .log_err()
1420                .flatten()
1421        } else {
1422            log::error!(
1423                "rect_for_text_range called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1424                self.view_id,
1425                self.view_name
1426            );
1427            None
1428        }
1429    }
1430
1431    fn debug(
1432        &self,
1433        bounds: RectF,
1434        _: &Self::LayoutState,
1435        _: &Self::PaintState,
1436        _: &V,
1437        cx: &ViewContext<V>,
1438    ) -> serde_json::Value {
1439        json!({
1440            "type": "ChildView",
1441            "bounds": bounds.to_json(),
1442            "child": if let Some(element) = cx.window.rendered_views.get(&self.view_id) {
1443                element.debug(&cx.window_context).log_err().unwrap_or_else(|| json!(null))
1444            } else {
1445                json!(null)
1446            }
1447        })
1448    }
1449}