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_button: Option<MouseButton>,
  57    mouse_position: Vector2F,
  58    text_layout_cache: TextLayoutCache,
  59}
  60
  61impl Window {
  62    pub fn new<V, F>(
  63        window_id: usize,
  64        platform_window: Box<dyn platform::Window>,
  65        cx: &mut AppContext,
  66        build_view: F,
  67    ) -> Self
  68    where
  69        F: FnOnce(&mut ViewContext<V>) -> V,
  70        V: View,
  71    {
  72        let titlebar_height = platform_window.titlebar_height();
  73        let appearance = platform_window.appearance();
  74        let mut window = Self {
  75            root_view: None,
  76            focused_view_id: None,
  77            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_button: 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_type = 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_type.extend(
 372                        actions
 373                            .keys()
 374                            .copied()
 375                            .map(|action_type| (action_type, depth)),
 376                    );
 377                }
 378            } else {
 379                log::error!(
 380                    "view {} not found when computing available actions",
 381                    view_id
 382                );
 383            }
 384        }
 385
 386        handler_depths_by_action_type.extend(
 387            self.global_actions
 388                .keys()
 389                .copied()
 390                .map(|action_type| (action_type, contexts.len())),
 391        );
 392
 393        self.action_deserializers
 394            .iter()
 395            .filter_map(move |(name, (type_id, deserialize))| {
 396                if let Some(action_depth) = handler_depths_by_action_type.get(type_id).copied() {
 397                    let action = deserialize(serde_json::Value::Object(Default::default())).ok()?;
 398                    let bindings = self
 399                        .keystroke_matcher
 400                        .bindings_for_action_type(*type_id)
 401                        .filter(|b| {
 402                            action.eq(b.action())
 403                                && (0..=action_depth)
 404                                    .any(|depth| b.match_context(&contexts[depth..]))
 405                        })
 406                        .cloned()
 407                        .collect();
 408                    Some((*name, action, bindings))
 409                } else {
 410                    None
 411                }
 412            })
 413            .collect()
 414    }
 415
 416    pub(crate) fn dispatch_keystroke(&mut self, keystroke: &Keystroke) -> bool {
 417        let window_id = self.window_id;
 418        if let Some(focused_view_id) = self.focused_view_id() {
 419            let dispatch_path = self
 420                .ancestors(focused_view_id)
 421                .filter_map(|view_id| {
 422                    self.views_metadata
 423                        .get(&(window_id, view_id))
 424                        .map(|view| (view_id, view.keymap_context.clone()))
 425                })
 426                .collect();
 427
 428            let match_result = self
 429                .keystroke_matcher
 430                .push_keystroke(keystroke.clone(), dispatch_path);
 431            let mut handled_by = None;
 432
 433            let keystroke_handled = match &match_result {
 434                MatchResult::None => false,
 435                MatchResult::Pending => true,
 436                MatchResult::Matches(matches) => {
 437                    for (view_id, action) in matches {
 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 clicked_button stored, don't replace it.
 484                if self.window.clicked_button.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                    self.window.clicked_button = Some(e.button);
 499                }
 500
 501                mouse_events.push(MouseEvent::Down(MouseDown {
 502                    region: Default::default(),
 503                    platform_event: e.clone(),
 504                }));
 505                mouse_events.push(MouseEvent::DownOut(MouseDownOut {
 506                    region: Default::default(),
 507                    platform_event: e.clone(),
 508                }));
 509            }
 510
 511            Event::MouseUp(e) => {
 512                // NOTE: The order of event pushes is important! MouseUp events MUST be fired
 513                // before click events, and so the MouseUp events need to be pushed before
 514                // MouseClick events.
 515                mouse_events.push(MouseEvent::Up(MouseUp {
 516                    region: Default::default(),
 517                    platform_event: e.clone(),
 518                }));
 519                mouse_events.push(MouseEvent::UpOut(MouseUpOut {
 520                    region: Default::default(),
 521                    platform_event: e.clone(),
 522                }));
 523                mouse_events.push(MouseEvent::Click(MouseClick {
 524                    region: Default::default(),
 525                    platform_event: e.clone(),
 526                }));
 527                mouse_events.push(MouseEvent::ClickOut(MouseClickOut {
 528                    region: Default::default(),
 529                    platform_event: e.clone(),
 530                }));
 531            }
 532
 533            Event::MouseMoved(
 534                e @ MouseMovedEvent {
 535                    position,
 536                    pressed_button,
 537                    ..
 538                },
 539            ) => {
 540                let mut style_to_assign = CursorStyle::Arrow;
 541                for region in self.window.cursor_regions.iter().rev() {
 542                    if region.bounds.contains_point(*position) {
 543                        style_to_assign = region.style;
 544                        break;
 545                    }
 546                }
 547
 548                if self
 549                    .window
 550                    .platform_window
 551                    .is_topmost_for_position(*position)
 552                {
 553                    self.platform().set_cursor_style(style_to_assign);
 554                }
 555
 556                if !event_reused {
 557                    if pressed_button.is_some() {
 558                        mouse_events.push(MouseEvent::Drag(MouseDrag {
 559                            region: Default::default(),
 560                            prev_mouse_position: self.window.mouse_position,
 561                            platform_event: e.clone(),
 562                        }));
 563                    } else if let Some(clicked_button) = self.window.clicked_button {
 564                        // Mouse up event happened outside the current window. Simulate mouse up button event
 565                        let button_event = e.to_button_event(clicked_button);
 566                        mouse_events.push(MouseEvent::Up(MouseUp {
 567                            region: Default::default(),
 568                            platform_event: button_event.clone(),
 569                        }));
 570                        mouse_events.push(MouseEvent::UpOut(MouseUpOut {
 571                            region: Default::default(),
 572                            platform_event: button_event.clone(),
 573                        }));
 574                        mouse_events.push(MouseEvent::Click(MouseClick {
 575                            region: Default::default(),
 576                            platform_event: button_event.clone(),
 577                        }));
 578                    }
 579
 580                    mouse_events.push(MouseEvent::Move(MouseMove {
 581                        region: Default::default(),
 582                        platform_event: e.clone(),
 583                    }));
 584                }
 585
 586                mouse_events.push(MouseEvent::Hover(MouseHover {
 587                    region: Default::default(),
 588                    platform_event: e.clone(),
 589                    started: false,
 590                }));
 591                mouse_events.push(MouseEvent::MoveOut(MouseMoveOut {
 592                    region: Default::default(),
 593                }));
 594
 595                self.window.last_mouse_moved_event = Some(event.clone());
 596            }
 597
 598            Event::MouseExited(event) => {
 599                // When the platform sends a MouseExited event, synthesize
 600                // a MouseMoved event whose position is outside the window's
 601                // bounds so that hover and cursor state can be updated.
 602                return self.dispatch_event(
 603                    Event::MouseMoved(MouseMovedEvent {
 604                        position: event.position,
 605                        pressed_button: event.pressed_button,
 606                        modifiers: event.modifiers,
 607                    }),
 608                    event_reused,
 609                );
 610            }
 611
 612            Event::ScrollWheel(e) => mouse_events.push(MouseEvent::ScrollWheel(MouseScrollWheel {
 613                region: Default::default(),
 614                platform_event: e.clone(),
 615            })),
 616        }
 617
 618        if let Some(position) = event.position() {
 619            self.window.mouse_position = position;
 620        }
 621
 622        // 2. Dispatch mouse events on regions
 623        let mut any_event_handled = false;
 624        for mut mouse_event in mouse_events {
 625            let mut valid_regions = Vec::new();
 626
 627            // GPUI elements are arranged by z_index but sibling elements can register overlapping
 628            // mouse regions. As such, hover events are only fired on overlapping elements which
 629            // are at the same z-index as the topmost element which overlaps with the mouse.
 630            match &mouse_event {
 631                MouseEvent::Hover(_) => {
 632                    let mut highest_z_index = None;
 633                    let mouse_position = self.window.mouse_position.clone();
 634                    let window = &mut *self.window;
 635                    for (region, z_index) in window.mouse_regions.iter().rev() {
 636                        // Allow mouse regions to appear transparent to hovers
 637                        if !region.hoverable {
 638                            continue;
 639                        }
 640
 641                        let contains_mouse = region.bounds.contains_point(mouse_position);
 642
 643                        if contains_mouse && highest_z_index.is_none() {
 644                            highest_z_index = Some(z_index);
 645                        }
 646
 647                        // This unwrap relies on short circuiting boolean expressions
 648                        // The right side of the && is only executed when contains_mouse
 649                        // is true, and we know above that when contains_mouse is true
 650                        // highest_z_index is set.
 651                        if contains_mouse && z_index == highest_z_index.unwrap() {
 652                            //Ensure that hover entrance events aren't sent twice
 653                            if window.hovered_region_ids.insert(region.id()) {
 654                                valid_regions.push(region.clone());
 655                                if region.notify_on_hover {
 656                                    notified_views.insert(region.id().view_id());
 657                                }
 658                            }
 659                        } else {
 660                            // Ensure that hover exit events aren't sent twice
 661                            if window.hovered_region_ids.remove(&region.id()) {
 662                                valid_regions.push(region.clone());
 663                                if region.notify_on_hover {
 664                                    notified_views.insert(region.id().view_id());
 665                                }
 666                            }
 667                        }
 668                    }
 669                }
 670
 671                MouseEvent::Down(_) | MouseEvent::Up(_) => {
 672                    for (region, _) in self.window.mouse_regions.iter().rev() {
 673                        if region.bounds.contains_point(self.window.mouse_position) {
 674                            valid_regions.push(region.clone());
 675                            if region.notify_on_click {
 676                                notified_views.insert(region.id().view_id());
 677                            }
 678                        }
 679                    }
 680                }
 681
 682                MouseEvent::Click(e) => {
 683                    // Only raise click events if the released button is the same as the one stored
 684                    if self
 685                        .window
 686                        .clicked_button
 687                        .map(|clicked_button| clicked_button == e.button)
 688                        .unwrap_or(false)
 689                    {
 690                        // Clear clicked regions and clicked button
 691                        let clicked_region_ids = std::mem::replace(
 692                            &mut self.window.clicked_region_ids,
 693                            Default::default(),
 694                        );
 695                        self.window.clicked_button = None;
 696
 697                        // Find regions which still overlap with the mouse since the last MouseDown happened
 698                        for (mouse_region, _) in self.window.mouse_regions.iter().rev() {
 699                            if clicked_region_ids.contains(&mouse_region.id()) {
 700                                if mouse_region
 701                                    .bounds
 702                                    .contains_point(self.window.mouse_position)
 703                                {
 704                                    valid_regions.push(mouse_region.clone());
 705                                }
 706                            }
 707                        }
 708                    }
 709                }
 710
 711                MouseEvent::Drag(_) => {
 712                    for (mouse_region, _) in self.window.mouse_regions.iter().rev() {
 713                        if self.window.clicked_region_ids.contains(&mouse_region.id()) {
 714                            valid_regions.push(mouse_region.clone());
 715                        }
 716                    }
 717                }
 718
 719                MouseEvent::MoveOut(_)
 720                | MouseEvent::UpOut(_)
 721                | MouseEvent::DownOut(_)
 722                | MouseEvent::ClickOut(_) => {
 723                    for (mouse_region, _) in self.window.mouse_regions.iter().rev() {
 724                        // NOT contains
 725                        if !mouse_region
 726                            .bounds
 727                            .contains_point(self.window.mouse_position)
 728                        {
 729                            valid_regions.push(mouse_region.clone());
 730                        }
 731                    }
 732                }
 733
 734                _ => {
 735                    for (mouse_region, _) in self.window.mouse_regions.iter().rev() {
 736                        // Contains
 737                        if mouse_region
 738                            .bounds
 739                            .contains_point(self.window.mouse_position)
 740                        {
 741                            valid_regions.push(mouse_region.clone());
 742                        }
 743                    }
 744                }
 745            }
 746
 747            //3. Fire region events
 748            let hovered_region_ids = self.window.hovered_region_ids.clone();
 749            for valid_region in valid_regions.into_iter() {
 750                let mut handled = false;
 751                mouse_event.set_region(valid_region.bounds);
 752                if let MouseEvent::Hover(e) = &mut mouse_event {
 753                    e.started = hovered_region_ids.contains(&valid_region.id())
 754                }
 755                // Handle Down events if the MouseRegion has a Click or Drag handler. This makes the api more intuitive as you would
 756                // not expect a MouseRegion to be transparent to Down events if it also has a Click handler.
 757                // This behavior can be overridden by adding a Down handler
 758                if let MouseEvent::Down(e) = &mouse_event {
 759                    let has_click = valid_region
 760                        .handlers
 761                        .contains(MouseEvent::click_disc(), Some(e.button));
 762                    let has_drag = valid_region
 763                        .handlers
 764                        .contains(MouseEvent::drag_disc(), Some(e.button));
 765                    let has_down = valid_region
 766                        .handlers
 767                        .contains(MouseEvent::down_disc(), Some(e.button));
 768                    if !has_down && (has_click || has_drag) {
 769                        handled = true;
 770                    }
 771                }
 772
 773                // `event_consumed` should only be true if there are any handlers for this event.
 774                let mut event_consumed = handled;
 775                if let Some(callbacks) = valid_region.handlers.get(&mouse_event.handler_key()) {
 776                    for callback in callbacks {
 777                        handled = true;
 778                        let view_id = valid_region.id().view_id();
 779                        self.update_any_view(view_id, |view, cx| {
 780                            handled = callback(mouse_event.clone(), view.as_any_mut(), cx, view_id);
 781                        });
 782                        event_consumed |= handled;
 783                        any_event_handled |= handled;
 784                    }
 785                }
 786
 787                any_event_handled |= handled;
 788
 789                // For bubbling events, if the event was handled, don't continue dispatching.
 790                // This only makes sense for local events which return false from is_capturable.
 791                if event_consumed && mouse_event.is_capturable() {
 792                    break;
 793                }
 794            }
 795        }
 796
 797        for view_id in notified_views {
 798            self.notify_view(window_id, view_id);
 799        }
 800
 801        any_event_handled
 802    }
 803
 804    pub(crate) fn dispatch_key_down(&mut self, event: &KeyDownEvent) -> bool {
 805        let window_id = self.window_id;
 806        if let Some(focused_view_id) = self.window.focused_view_id {
 807            for view_id in self.ancestors(focused_view_id).collect::<Vec<_>>() {
 808                if let Some(mut view) = self.views.remove(&(window_id, view_id)) {
 809                    let handled = view.key_down(event, self, view_id);
 810                    self.views.insert((window_id, view_id), view);
 811                    if handled {
 812                        return true;
 813                    }
 814                } else {
 815                    log::error!("view {} does not exist", view_id)
 816                }
 817            }
 818        }
 819
 820        false
 821    }
 822
 823    pub(crate) fn dispatch_key_up(&mut self, event: &KeyUpEvent) -> bool {
 824        let window_id = self.window_id;
 825        if let Some(focused_view_id) = self.window.focused_view_id {
 826            for view_id in self.ancestors(focused_view_id).collect::<Vec<_>>() {
 827                if let Some(mut view) = self.views.remove(&(window_id, view_id)) {
 828                    let handled = view.key_up(event, self, view_id);
 829                    self.views.insert((window_id, view_id), view);
 830                    if handled {
 831                        return true;
 832                    }
 833                } else {
 834                    log::error!("view {} does not exist", view_id)
 835                }
 836            }
 837        }
 838
 839        false
 840    }
 841
 842    pub(crate) fn dispatch_modifiers_changed(&mut self, event: &ModifiersChangedEvent) -> bool {
 843        let window_id = self.window_id;
 844        if let Some(focused_view_id) = self.window.focused_view_id {
 845            for view_id in self.ancestors(focused_view_id).collect::<Vec<_>>() {
 846                if let Some(mut view) = self.views.remove(&(window_id, view_id)) {
 847                    let handled = view.modifiers_changed(event, self, view_id);
 848                    self.views.insert((window_id, view_id), view);
 849                    if handled {
 850                        return true;
 851                    }
 852                } else {
 853                    log::error!("view {} does not exist", view_id)
 854                }
 855            }
 856        }
 857
 858        false
 859    }
 860
 861    pub fn invalidate(&mut self, mut invalidation: WindowInvalidation, appearance: Appearance) {
 862        self.start_frame();
 863        self.window.appearance = appearance;
 864        for view_id in &invalidation.removed {
 865            invalidation.updated.remove(view_id);
 866            self.window.rendered_views.remove(view_id);
 867        }
 868        for view_id in &invalidation.updated {
 869            let titlebar_height = self.window.titlebar_height;
 870            let hovered_region_ids = self.window.hovered_region_ids.clone();
 871            let clicked_region_ids = self
 872                .window
 873                .clicked_button
 874                .map(|button| (self.window.clicked_region_ids.clone(), button));
 875
 876            let element = self
 877                .render_view(RenderParams {
 878                    view_id: *view_id,
 879                    titlebar_height,
 880                    hovered_region_ids,
 881                    clicked_region_ids,
 882                    refreshing: false,
 883                    appearance,
 884                })
 885                .unwrap();
 886            self.window.rendered_views.insert(*view_id, element);
 887        }
 888    }
 889
 890    pub fn render_view(&mut self, params: RenderParams) -> Result<Box<dyn AnyRootElement>> {
 891        let window_id = self.window_id;
 892        let view_id = params.view_id;
 893        let mut view = self
 894            .views
 895            .remove(&(window_id, view_id))
 896            .ok_or_else(|| anyhow!("view not found"))?;
 897        let element = view.render(self, view_id);
 898        self.views.insert((window_id, view_id), view);
 899        Ok(element)
 900    }
 901
 902    pub(crate) fn layout(&mut self, refreshing: bool) -> Result<HashMap<usize, usize>> {
 903        let window_size = self.window.platform_window.content_size();
 904        let root_view_id = self.window.root_view().id();
 905        let mut rendered_root = self.window.rendered_views.remove(&root_view_id).unwrap();
 906        let mut new_parents = HashMap::default();
 907        let mut views_to_notify_if_ancestors_change = HashMap::default();
 908        rendered_root.layout(
 909            SizeConstraint::strict(window_size),
 910            &mut new_parents,
 911            &mut views_to_notify_if_ancestors_change,
 912            refreshing,
 913            self,
 914        )?;
 915
 916        for (view_id, view_ids_to_notify) in views_to_notify_if_ancestors_change {
 917            let mut current_view_id = view_id;
 918            loop {
 919                let old_parent_id = self.window.parents.get(&current_view_id);
 920                let new_parent_id = new_parents.get(&current_view_id);
 921                if old_parent_id.is_none() && new_parent_id.is_none() {
 922                    break;
 923                } else if old_parent_id == new_parent_id {
 924                    current_view_id = *old_parent_id.unwrap();
 925                } else {
 926                    let window_id = self.window_id;
 927                    for view_id_to_notify in view_ids_to_notify {
 928                        self.notify_view(window_id, view_id_to_notify);
 929                    }
 930                    break;
 931                }
 932            }
 933        }
 934
 935        let old_parents = mem::replace(&mut self.window.parents, new_parents);
 936        self.window
 937            .rendered_views
 938            .insert(root_view_id, rendered_root);
 939        Ok(old_parents)
 940    }
 941
 942    pub(crate) fn paint(&mut self) -> Result<Scene> {
 943        let window_size = self.window.platform_window.content_size();
 944        let scale_factor = self.window.platform_window.scale_factor();
 945
 946        let root_view_id = self.window.root_view().id();
 947        let mut rendered_root = self.window.rendered_views.remove(&root_view_id).unwrap();
 948
 949        let mut scene_builder = SceneBuilder::new(scale_factor);
 950        rendered_root.paint(
 951            &mut scene_builder,
 952            Vector2F::zero(),
 953            RectF::from_points(Vector2F::zero(), window_size),
 954            self,
 955        )?;
 956        self.window
 957            .rendered_views
 958            .insert(root_view_id, rendered_root);
 959
 960        self.window.text_layout_cache.finish_frame();
 961        let scene = scene_builder.build();
 962        self.window.cursor_regions = scene.cursor_regions();
 963        self.window.mouse_regions = scene.mouse_regions();
 964
 965        if self.window_is_active() {
 966            if let Some(event) = self.window.last_mouse_moved_event.clone() {
 967                self.dispatch_event(event, true);
 968            }
 969        }
 970
 971        Ok(scene)
 972    }
 973
 974    pub fn rect_for_text_range(&self, range_utf16: Range<usize>) -> Option<RectF> {
 975        let focused_view_id = self.window.focused_view_id?;
 976        self.window
 977            .rendered_views
 978            .get(&focused_view_id)?
 979            .rect_for_text_range(range_utf16, self)
 980            .log_err()
 981            .flatten()
 982    }
 983
 984    pub fn set_window_title(&mut self, title: &str) {
 985        self.window.platform_window.set_title(title);
 986    }
 987
 988    pub fn set_window_edited(&mut self, edited: bool) {
 989        self.window.platform_window.set_edited(edited);
 990    }
 991
 992    pub fn is_topmost_window_for_position(&self, position: Vector2F) -> bool {
 993        self.window
 994            .platform_window
 995            .is_topmost_for_position(position)
 996    }
 997
 998    pub fn activate_window(&self) {
 999        self.window.platform_window.activate();
1000    }
1001
1002    pub fn window_is_active(&self) -> bool {
1003        self.window.is_active
1004    }
1005
1006    pub fn window_is_fullscreen(&self) -> bool {
1007        self.window.is_fullscreen
1008    }
1009
1010    pub(crate) fn dispatch_action(&mut self, view_id: Option<usize>, action: &dyn Action) -> bool {
1011        if let Some(view_id) = view_id {
1012            self.halt_action_dispatch = false;
1013            self.visit_dispatch_path(view_id, |view_id, capture_phase, cx| {
1014                cx.update_any_view(view_id, |view, cx| {
1015                    let type_id = view.as_any().type_id();
1016                    if let Some((name, mut handlers)) = cx
1017                        .actions_mut(capture_phase)
1018                        .get_mut(&type_id)
1019                        .and_then(|h| h.remove_entry(&action.id()))
1020                    {
1021                        for handler in handlers.iter_mut().rev() {
1022                            cx.halt_action_dispatch = true;
1023                            handler(view, action, cx, view_id);
1024                            if cx.halt_action_dispatch {
1025                                break;
1026                            }
1027                        }
1028                        cx.actions_mut(capture_phase)
1029                            .get_mut(&type_id)
1030                            .unwrap()
1031                            .insert(name, handlers);
1032                    }
1033                });
1034
1035                !cx.halt_action_dispatch
1036            });
1037        }
1038
1039        if !self.halt_action_dispatch {
1040            self.halt_action_dispatch = self.dispatch_global_action_any(action);
1041        }
1042
1043        self.pending_effects
1044            .push_back(Effect::ActionDispatchNotification {
1045                action_id: action.id(),
1046            });
1047        self.halt_action_dispatch
1048    }
1049
1050    /// Returns an iterator over all of the view ids from the passed view up to the root of the window
1051    /// Includes the passed view itself
1052    pub(crate) fn ancestors(&self, mut view_id: usize) -> impl Iterator<Item = usize> + '_ {
1053        std::iter::once(view_id)
1054            .into_iter()
1055            .chain(std::iter::from_fn(move || {
1056                if let Some(parent_id) = self.window.parents.get(&view_id) {
1057                    view_id = *parent_id;
1058                    Some(view_id)
1059                } else {
1060                    None
1061                }
1062            }))
1063    }
1064
1065    // Traverses the parent tree. Walks down the tree toward the passed
1066    // view calling visit with true. Then walks back up the tree calling visit with false.
1067    // If `visit` returns false this function will immediately return.
1068    fn visit_dispatch_path(
1069        &mut self,
1070        view_id: usize,
1071        mut visit: impl FnMut(usize, bool, &mut WindowContext) -> bool,
1072    ) {
1073        // List of view ids from the leaf to the root of the window
1074        let path = self.ancestors(view_id).collect::<Vec<_>>();
1075
1076        // Walk down from the root to the leaf calling visit with capture_phase = true
1077        for view_id in path.iter().rev() {
1078            if !visit(*view_id, true, self) {
1079                return;
1080            }
1081        }
1082
1083        // Walk up from the leaf to the root calling visit with capture_phase = false
1084        for view_id in path.iter() {
1085            if !visit(*view_id, false, self) {
1086                return;
1087            }
1088        }
1089    }
1090
1091    pub fn focused_view_id(&self) -> Option<usize> {
1092        self.window.focused_view_id
1093    }
1094
1095    pub fn window_bounds(&self) -> WindowBounds {
1096        self.window.platform_window.bounds()
1097    }
1098
1099    pub fn window_appearance(&self) -> Appearance {
1100        self.window.appearance
1101    }
1102
1103    pub fn window_display_uuid(&self) -> Option<Uuid> {
1104        self.window.platform_window.screen().display_uuid()
1105    }
1106
1107    pub fn show_character_palette(&self) {
1108        self.window.platform_window.show_character_palette();
1109    }
1110
1111    pub fn minimize_window(&self) {
1112        self.window.platform_window.minimize();
1113    }
1114
1115    pub fn zoom_window(&self) {
1116        self.window.platform_window.zoom();
1117    }
1118
1119    pub fn toggle_full_screen(&self) {
1120        self.window.platform_window.toggle_full_screen();
1121    }
1122
1123    pub fn prompt(
1124        &self,
1125        level: PromptLevel,
1126        msg: &str,
1127        answers: &[&str],
1128    ) -> oneshot::Receiver<usize> {
1129        self.window.platform_window.prompt(level, msg, answers)
1130    }
1131
1132    pub fn replace_root_view<V, F>(&mut self, build_root_view: F) -> ViewHandle<V>
1133    where
1134        V: View,
1135        F: FnOnce(&mut ViewContext<V>) -> V,
1136    {
1137        let root_view = self.add_view(|cx| build_root_view(cx));
1138        self.window.root_view = Some(root_view.clone().into_any());
1139        self.window.focused_view_id = Some(root_view.id());
1140        root_view
1141    }
1142
1143    pub fn add_view<T, F>(&mut self, build_view: F) -> ViewHandle<T>
1144    where
1145        T: View,
1146        F: FnOnce(&mut ViewContext<T>) -> T,
1147    {
1148        self.add_option_view(|cx| Some(build_view(cx))).unwrap()
1149    }
1150
1151    pub fn add_option_view<T, F>(&mut self, build_view: F) -> Option<ViewHandle<T>>
1152    where
1153        T: View,
1154        F: FnOnce(&mut ViewContext<T>) -> Option<T>,
1155    {
1156        let window_id = self.window_id;
1157        let view_id = post_inc(&mut self.next_entity_id);
1158        let mut cx = ViewContext::mutable(self, view_id);
1159        let handle = if let Some(view) = build_view(&mut cx) {
1160            let mut keymap_context = KeymapContext::default();
1161            view.update_keymap_context(&mut keymap_context, cx.app_context());
1162            self.views_metadata.insert(
1163                (window_id, view_id),
1164                ViewMetadata {
1165                    type_id: TypeId::of::<T>(),
1166                    keymap_context,
1167                },
1168            );
1169            self.views.insert((window_id, view_id), Box::new(view));
1170            self.window
1171                .invalidation
1172                .get_or_insert_with(Default::default)
1173                .updated
1174                .insert(view_id);
1175            Some(ViewHandle::new(window_id, view_id, &self.ref_counts))
1176        } else {
1177            None
1178        };
1179        handle
1180    }
1181}
1182
1183pub struct RenderParams {
1184    pub view_id: usize,
1185    pub titlebar_height: f32,
1186    pub hovered_region_ids: HashSet<MouseRegionId>,
1187    pub clicked_region_ids: Option<(HashSet<MouseRegionId>, MouseButton)>,
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}