1use crate::{
2 app::{AppContext, MutableAppContext, WindowInvalidation},
3 elements::Element,
4 font_cache::FontCache,
5 geometry::rect::RectF,
6 json::{self, ToJson},
7 keymap_matcher::Keystroke,
8 platform::{CursorStyle, Event},
9 scene::{
10 CursorRegion, MouseClick, MouseDown, MouseDownOut, MouseDrag, MouseEvent, MouseHover,
11 MouseMove, MouseMoveOut, MouseScrollWheel, MouseUp, MouseUpOut, Scene,
12 },
13 text_layout::TextLayoutCache,
14 Action, AnyModelHandle, AnyViewHandle, AnyWeakModelHandle, AnyWeakViewHandle, Appearance,
15 AssetCache, ElementBox, Entity, FontSystem, ModelHandle, MouseButton, MouseMovedEvent,
16 MouseRegion, MouseRegionId, ParentId, ReadModel, ReadView, RenderContext, RenderParams,
17 SceneBuilder, UpgradeModelHandle, UpgradeViewHandle, View, ViewHandle, WeakModelHandle,
18 WeakViewHandle,
19};
20use anyhow::bail;
21use collections::{HashMap, HashSet};
22use pathfinder_geometry::vector::{vec2f, Vector2F};
23use serde_json::json;
24use smallvec::SmallVec;
25use sqlez::{
26 bindable::{Bind, Column},
27 statement::Statement,
28};
29use std::{
30 marker::PhantomData,
31 ops::{Deref, DerefMut, Range},
32 sync::Arc,
33};
34
35pub struct Presenter {
36 window_id: usize,
37 pub(crate) rendered_views: HashMap<usize, ElementBox>,
38 cursor_regions: Vec<CursorRegion>,
39 mouse_regions: Vec<(MouseRegion, usize)>,
40 font_cache: Arc<FontCache>,
41 text_layout_cache: TextLayoutCache,
42 asset_cache: Arc<AssetCache>,
43 last_mouse_moved_event: Option<Event>,
44 hovered_region_ids: HashSet<MouseRegionId>,
45 clicked_region_ids: HashSet<MouseRegionId>,
46 clicked_button: Option<MouseButton>,
47 mouse_position: Vector2F,
48 titlebar_height: f32,
49 appearance: Appearance,
50}
51
52impl Presenter {
53 pub fn new(
54 window_id: usize,
55 titlebar_height: f32,
56 appearance: Appearance,
57 font_cache: Arc<FontCache>,
58 text_layout_cache: TextLayoutCache,
59 asset_cache: Arc<AssetCache>,
60 cx: &mut MutableAppContext,
61 ) -> Self {
62 Self {
63 window_id,
64 rendered_views: cx.render_views(window_id, titlebar_height, appearance),
65 cursor_regions: Default::default(),
66 mouse_regions: Default::default(),
67 font_cache,
68 text_layout_cache,
69 asset_cache,
70 last_mouse_moved_event: None,
71 hovered_region_ids: Default::default(),
72 clicked_region_ids: Default::default(),
73 clicked_button: None,
74 mouse_position: vec2f(0., 0.),
75 titlebar_height,
76 appearance,
77 }
78 }
79
80 pub fn invalidate(
81 &mut self,
82 invalidation: &mut WindowInvalidation,
83 appearance: Appearance,
84 cx: &mut MutableAppContext,
85 ) {
86 cx.start_frame();
87 self.appearance = appearance;
88 for view_id in &invalidation.removed {
89 invalidation.updated.remove(view_id);
90 self.rendered_views.remove(view_id);
91 }
92 for view_id in &invalidation.updated {
93 self.rendered_views.insert(
94 *view_id,
95 cx.render_view(RenderParams {
96 window_id: self.window_id,
97 view_id: *view_id,
98 titlebar_height: self.titlebar_height,
99 hovered_region_ids: self.hovered_region_ids.clone(),
100 clicked_region_ids: self
101 .clicked_button
102 .map(|button| (self.clicked_region_ids.clone(), button)),
103 refreshing: false,
104 appearance,
105 })
106 .unwrap(),
107 );
108 }
109 }
110
111 pub fn refresh(
112 &mut self,
113 invalidation: &mut WindowInvalidation,
114 appearance: Appearance,
115 cx: &mut MutableAppContext,
116 ) {
117 self.invalidate(invalidation, appearance, cx);
118 for (view_id, view) in &mut self.rendered_views {
119 if !invalidation.updated.contains(view_id) {
120 *view = cx
121 .render_view(RenderParams {
122 window_id: self.window_id,
123 view_id: *view_id,
124 titlebar_height: self.titlebar_height,
125 hovered_region_ids: self.hovered_region_ids.clone(),
126 clicked_region_ids: self
127 .clicked_button
128 .map(|button| (self.clicked_region_ids.clone(), button)),
129 refreshing: true,
130 appearance,
131 })
132 .unwrap();
133 }
134 }
135 }
136
137 pub fn build_scene(
138 &mut self,
139 window_size: Vector2F,
140 scale_factor: f32,
141 refreshing: bool,
142 cx: &mut MutableAppContext,
143 ) -> Scene {
144 let mut scene_builder = SceneBuilder::new(scale_factor);
145
146 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
147 self.layout(window_size, refreshing, cx);
148 let mut paint_cx = self.build_paint_context(&mut scene_builder, window_size, cx);
149 paint_cx.paint(
150 root_view_id,
151 Vector2F::zero(),
152 RectF::new(Vector2F::zero(), window_size),
153 );
154 self.text_layout_cache.finish_frame();
155 let scene = scene_builder.build();
156 self.cursor_regions = scene.cursor_regions();
157 self.mouse_regions = scene.mouse_regions();
158
159 // window.is_topmost for the mouse moved event's postion?
160 if cx.window_is_active(self.window_id) {
161 if let Some(event) = self.last_mouse_moved_event.clone() {
162 self.dispatch_event(event, true, cx);
163 }
164 }
165
166 scene
167 } else {
168 log::error!("could not find root_view_id for window {}", self.window_id);
169 scene_builder.build()
170 }
171 }
172
173 fn layout(&mut self, window_size: Vector2F, refreshing: bool, cx: &mut MutableAppContext) {
174 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
175 self.build_layout_context(window_size, refreshing, cx)
176 .layout(root_view_id, SizeConstraint::strict(window_size));
177 }
178 }
179
180 pub fn build_layout_context<'a>(
181 &'a mut self,
182 window_size: Vector2F,
183 refreshing: bool,
184 cx: &'a mut MutableAppContext,
185 ) -> LayoutContext<'a> {
186 LayoutContext {
187 window_id: self.window_id,
188 rendered_views: &mut self.rendered_views,
189 font_cache: &self.font_cache,
190 font_system: cx.platform().fonts(),
191 text_layout_cache: &self.text_layout_cache,
192 asset_cache: &self.asset_cache,
193 view_stack: Vec::new(),
194 refreshing,
195 hovered_region_ids: self.hovered_region_ids.clone(),
196 clicked_region_ids: self
197 .clicked_button
198 .map(|button| (self.clicked_region_ids.clone(), button)),
199 titlebar_height: self.titlebar_height,
200 appearance: self.appearance,
201 window_size,
202 app: cx,
203 }
204 }
205
206 pub fn build_paint_context<'a>(
207 &'a mut self,
208 scene: &'a mut SceneBuilder,
209 window_size: Vector2F,
210 cx: &'a mut MutableAppContext,
211 ) -> PaintContext {
212 PaintContext {
213 scene,
214 window_size,
215 font_cache: &self.font_cache,
216 text_layout_cache: &self.text_layout_cache,
217 rendered_views: &mut self.rendered_views,
218 view_stack: Vec::new(),
219 app: cx,
220 }
221 }
222
223 pub fn rect_for_text_range(&self, range_utf16: Range<usize>, cx: &AppContext) -> Option<RectF> {
224 cx.focused_view_id(self.window_id).and_then(|view_id| {
225 let cx = MeasurementContext {
226 app: cx,
227 rendered_views: &self.rendered_views,
228 window_id: self.window_id,
229 };
230 cx.rect_for_text_range(view_id, range_utf16)
231 })
232 }
233
234 pub fn dispatch_event(
235 &mut self,
236 event: Event,
237 event_reused: bool,
238 cx: &mut MutableAppContext,
239 ) -> bool {
240 let mut mouse_events = SmallVec::<[_; 2]>::new();
241 let mut notified_views: HashSet<usize> = Default::default();
242
243 // 1. Handle platform event. Keyboard events get dispatched immediately, while mouse events
244 // get mapped into the mouse-specific MouseEvent type.
245 // -> These are usually small: [Mouse Down] or [Mouse up, Click] or [Mouse Moved, Mouse Dragged?]
246 // -> Also updates mouse-related state
247 match &event {
248 Event::KeyDown(e) => return cx.dispatch_key_down(self.window_id, e),
249
250 Event::KeyUp(e) => return cx.dispatch_key_up(self.window_id, e),
251
252 Event::ModifiersChanged(e) => return cx.dispatch_modifiers_changed(self.window_id, e),
253
254 Event::MouseDown(e) => {
255 // Click events are weird because they can be fired after a drag event.
256 // MDN says that browsers handle this by starting from 'the most
257 // specific ancestor element that contained both [positions]'
258 // So we need to store the overlapping regions on mouse down.
259
260 // If there is already clicked_button stored, don't replace it.
261 if self.clicked_button.is_none() {
262 self.clicked_region_ids = self
263 .mouse_regions
264 .iter()
265 .filter_map(|(region, _)| {
266 if region.bounds.contains_point(e.position) {
267 Some(region.id())
268 } else {
269 None
270 }
271 })
272 .collect();
273
274 self.clicked_button = Some(e.button);
275 }
276
277 mouse_events.push(MouseEvent::Down(MouseDown {
278 region: Default::default(),
279 platform_event: e.clone(),
280 }));
281 mouse_events.push(MouseEvent::DownOut(MouseDownOut {
282 region: Default::default(),
283 platform_event: e.clone(),
284 }));
285 }
286
287 Event::MouseUp(e) => {
288 // NOTE: The order of event pushes is important! MouseUp events MUST be fired
289 // before click events, and so the MouseUp events need to be pushed before
290 // MouseClick events.
291 mouse_events.push(MouseEvent::Up(MouseUp {
292 region: Default::default(),
293 platform_event: e.clone(),
294 }));
295 mouse_events.push(MouseEvent::UpOut(MouseUpOut {
296 region: Default::default(),
297 platform_event: e.clone(),
298 }));
299 mouse_events.push(MouseEvent::Click(MouseClick {
300 region: Default::default(),
301 platform_event: e.clone(),
302 }));
303 }
304
305 Event::MouseMoved(
306 e @ MouseMovedEvent {
307 position,
308 pressed_button,
309 ..
310 },
311 ) => {
312 let mut style_to_assign = CursorStyle::Arrow;
313 for region in self.cursor_regions.iter().rev() {
314 if region.bounds.contains_point(*position) {
315 style_to_assign = region.style;
316 break;
317 }
318 }
319 cx.platform().set_cursor_style(style_to_assign);
320
321 if !event_reused {
322 if pressed_button.is_some() {
323 mouse_events.push(MouseEvent::Drag(MouseDrag {
324 region: Default::default(),
325 prev_mouse_position: self.mouse_position,
326 platform_event: e.clone(),
327 }));
328 } else if let Some(clicked_button) = self.clicked_button {
329 // Mouse up event happened outside the current window. Simulate mouse up button event
330 let button_event = e.to_button_event(clicked_button);
331 mouse_events.push(MouseEvent::Up(MouseUp {
332 region: Default::default(),
333 platform_event: button_event.clone(),
334 }));
335 mouse_events.push(MouseEvent::UpOut(MouseUpOut {
336 region: Default::default(),
337 platform_event: button_event.clone(),
338 }));
339 mouse_events.push(MouseEvent::Click(MouseClick {
340 region: Default::default(),
341 platform_event: button_event.clone(),
342 }));
343 }
344
345 mouse_events.push(MouseEvent::Move(MouseMove {
346 region: Default::default(),
347 platform_event: e.clone(),
348 }));
349 }
350
351 mouse_events.push(MouseEvent::Hover(MouseHover {
352 region: Default::default(),
353 platform_event: e.clone(),
354 started: false,
355 }));
356 mouse_events.push(MouseEvent::MoveOut(MouseMoveOut {
357 region: Default::default(),
358 }));
359
360 self.last_mouse_moved_event = Some(event.clone());
361 }
362
363 Event::MouseExited(event) => {
364 // When the platform sends a MouseExited event, synthesize
365 // a MouseMoved event whose position is outside the window's
366 // bounds so that hover and cursor state can be updated.
367 return self.dispatch_event(
368 Event::MouseMoved(MouseMovedEvent {
369 position: event.position,
370 pressed_button: event.pressed_button,
371 modifiers: event.modifiers,
372 }),
373 event_reused,
374 cx,
375 );
376 }
377
378 Event::ScrollWheel(e) => mouse_events.push(MouseEvent::ScrollWheel(MouseScrollWheel {
379 region: Default::default(),
380 platform_event: e.clone(),
381 })),
382 }
383
384 if let Some(position) = event.position() {
385 self.mouse_position = position;
386 }
387
388 // 2. Dispatch mouse events on regions
389 let mut any_event_handled = false;
390 for mut mouse_event in mouse_events {
391 let mut valid_regions = Vec::new();
392
393 // GPUI elements are arranged by z_index but sibling elements can register overlapping
394 // mouse regions. As such, hover events are only fired on overlapping elements which
395 // are at the same z-index as the topmost element which overlaps with the mouse.
396 match &mouse_event {
397 MouseEvent::Hover(_) => {
398 let mut highest_z_index = None;
399 let mouse_position = self.mouse_position.clone();
400 for (region, z_index) in self.mouse_regions.iter().rev() {
401 // Allow mouse regions to appear transparent to hovers
402 if !region.hoverable {
403 continue;
404 }
405
406 let contains_mouse = region.bounds.contains_point(mouse_position);
407
408 if contains_mouse && highest_z_index.is_none() {
409 highest_z_index = Some(z_index);
410 }
411
412 // This unwrap relies on short circuiting boolean expressions
413 // The right side of the && is only executed when contains_mouse
414 // is true, and we know above that when contains_mouse is true
415 // highest_z_index is set.
416 if contains_mouse && z_index == highest_z_index.unwrap() {
417 //Ensure that hover entrance events aren't sent twice
418 if self.hovered_region_ids.insert(region.id()) {
419 valid_regions.push(region.clone());
420 if region.notify_on_hover {
421 notified_views.insert(region.id().view_id());
422 }
423 }
424 } else {
425 // Ensure that hover exit events aren't sent twice
426 if self.hovered_region_ids.remove(®ion.id()) {
427 valid_regions.push(region.clone());
428 if region.notify_on_hover {
429 notified_views.insert(region.id().view_id());
430 }
431 }
432 }
433 }
434 }
435
436 MouseEvent::Down(_) | MouseEvent::Up(_) => {
437 for (region, _) in self.mouse_regions.iter().rev() {
438 if region.bounds.contains_point(self.mouse_position) {
439 valid_regions.push(region.clone());
440 if region.notify_on_click {
441 notified_views.insert(region.id().view_id());
442 }
443 }
444 }
445 }
446
447 MouseEvent::Click(e) => {
448 // Only raise click events if the released button is the same as the one stored
449 if self
450 .clicked_button
451 .map(|clicked_button| clicked_button == e.button)
452 .unwrap_or(false)
453 {
454 // Clear clicked regions and clicked button
455 let clicked_region_ids =
456 std::mem::replace(&mut self.clicked_region_ids, Default::default());
457 self.clicked_button = None;
458
459 // Find regions which still overlap with the mouse since the last MouseDown happened
460 for (mouse_region, _) in self.mouse_regions.iter().rev() {
461 if clicked_region_ids.contains(&mouse_region.id()) {
462 if mouse_region.bounds.contains_point(self.mouse_position) {
463 valid_regions.push(mouse_region.clone());
464 }
465 }
466 }
467 }
468 }
469
470 MouseEvent::Drag(_) => {
471 for (mouse_region, _) in self.mouse_regions.iter().rev() {
472 if self.clicked_region_ids.contains(&mouse_region.id()) {
473 valid_regions.push(mouse_region.clone());
474 }
475 }
476 }
477
478 MouseEvent::MoveOut(_) | MouseEvent::UpOut(_) | MouseEvent::DownOut(_) => {
479 for (mouse_region, _) in self.mouse_regions.iter().rev() {
480 // NOT contains
481 if !mouse_region.bounds.contains_point(self.mouse_position) {
482 valid_regions.push(mouse_region.clone());
483 }
484 }
485 }
486
487 _ => {
488 for (mouse_region, _) in self.mouse_regions.iter().rev() {
489 // Contains
490 if mouse_region.bounds.contains_point(self.mouse_position) {
491 valid_regions.push(mouse_region.clone());
492 }
493 }
494 }
495 }
496
497 //3. Fire region events
498 let hovered_region_ids = self.hovered_region_ids.clone();
499 for valid_region in valid_regions.into_iter() {
500 let mut event_cx = self.build_event_context(&mut notified_views, cx);
501
502 mouse_event.set_region(valid_region.bounds);
503 if let MouseEvent::Hover(e) = &mut mouse_event {
504 e.started = hovered_region_ids.contains(&valid_region.id())
505 }
506 // Handle Down events if the MouseRegion has a Click or Drag handler. This makes the api more intuitive as you would
507 // not expect a MouseRegion to be transparent to Down events if it also has a Click handler.
508 // This behavior can be overridden by adding a Down handler that calls cx.propogate_event
509 if let MouseEvent::Down(e) = &mouse_event {
510 if valid_region
511 .handlers
512 .contains(MouseEvent::click_disc(), Some(e.button))
513 || valid_region
514 .handlers
515 .contains(MouseEvent::drag_disc(), Some(e.button))
516 {
517 event_cx.handled = true;
518 }
519 }
520
521 // `event_consumed` should only be true if there are any handlers for this event.
522 let mut event_consumed = event_cx.handled;
523 if let Some(callbacks) = valid_region.handlers.get(&mouse_event.handler_key()) {
524 event_consumed = true;
525 for callback in callbacks {
526 event_cx.handled = true;
527 event_cx.with_current_view(valid_region.id().view_id(), {
528 let region_event = mouse_event.clone();
529 |cx| callback(region_event, cx)
530 });
531 event_consumed &= event_cx.handled;
532 any_event_handled |= event_cx.handled;
533 }
534 }
535
536 any_event_handled |= event_cx.handled;
537
538 // For bubbling events, if the event was handled, don't continue dispatching.
539 // This only makes sense for local events which return false from is_capturable.
540 if event_consumed && mouse_event.is_capturable() {
541 break;
542 }
543 }
544 }
545
546 for view_id in notified_views {
547 cx.notify_view(self.window_id, view_id);
548 }
549
550 any_event_handled
551 }
552
553 pub fn build_event_context<'a>(
554 &'a mut self,
555 notified_views: &'a mut HashSet<usize>,
556 cx: &'a mut MutableAppContext,
557 ) -> EventContext<'a> {
558 EventContext {
559 font_cache: &self.font_cache,
560 text_layout_cache: &self.text_layout_cache,
561 view_stack: Default::default(),
562 notified_views,
563 notify_count: 0,
564 handled: false,
565 window_id: self.window_id,
566 app: cx,
567 }
568 }
569
570 pub fn debug_elements(&self, cx: &AppContext) -> Option<json::Value> {
571 let view = cx.root_view(self.window_id)?;
572 Some(json!({
573 "root_view": view.debug_json(cx),
574 "root_element": self.rendered_views.get(&view.id())
575 .map(|root_element| {
576 root_element.debug(&DebugContext {
577 rendered_views: &self.rendered_views,
578 font_cache: &self.font_cache,
579 app: cx,
580 })
581 })
582 }))
583 }
584}
585
586pub struct LayoutContext<'a> {
587 window_id: usize,
588 rendered_views: &'a mut HashMap<usize, ElementBox>,
589 view_stack: Vec<usize>,
590 pub font_cache: &'a Arc<FontCache>,
591 pub font_system: Arc<dyn FontSystem>,
592 pub text_layout_cache: &'a TextLayoutCache,
593 pub asset_cache: &'a AssetCache,
594 pub app: &'a mut MutableAppContext,
595 pub refreshing: bool,
596 pub window_size: Vector2F,
597 titlebar_height: f32,
598 appearance: Appearance,
599 hovered_region_ids: HashSet<MouseRegionId>,
600 clicked_region_ids: Option<(HashSet<MouseRegionId>, MouseButton)>,
601}
602
603impl<'a> LayoutContext<'a> {
604 pub(crate) fn keystrokes_for_action(
605 &mut self,
606 action: &dyn Action,
607 ) -> Option<SmallVec<[Keystroke; 2]>> {
608 self.app
609 .keystrokes_for_action(self.window_id, &self.view_stack, action)
610 }
611
612 fn layout(&mut self, view_id: usize, constraint: SizeConstraint) -> Vector2F {
613 let print_error = |view_id| {
614 format!(
615 "{} with id {}",
616 self.app.name_for_view(self.window_id, view_id).unwrap(),
617 view_id,
618 )
619 };
620 match (
621 self.view_stack.last(),
622 self.app.parents.get(&(self.window_id, view_id)),
623 ) {
624 (Some(layout_parent), Some(ParentId::View(app_parent))) => {
625 if layout_parent != app_parent {
626 panic!(
627 "View {} was laid out with parent {} when it was constructed with parent {}",
628 print_error(view_id),
629 print_error(*layout_parent),
630 print_error(*app_parent))
631 }
632 }
633 (None, Some(ParentId::View(app_parent))) => panic!(
634 "View {} was laid out without a parent when it was constructed with parent {}",
635 print_error(view_id),
636 print_error(*app_parent)
637 ),
638 (Some(layout_parent), Some(ParentId::Root)) => panic!(
639 "View {} was laid out with parent {} when it was constructed as a window root",
640 print_error(view_id),
641 print_error(*layout_parent),
642 ),
643 (_, None) => panic!(
644 "View {} did not have a registered parent in the app context",
645 print_error(view_id),
646 ),
647 _ => {}
648 }
649
650 self.view_stack.push(view_id);
651 let mut rendered_view = self.rendered_views.remove(&view_id).unwrap();
652 let size = rendered_view.layout(constraint, self);
653 self.rendered_views.insert(view_id, rendered_view);
654 self.view_stack.pop();
655 size
656 }
657
658 pub fn render<F, V, T>(&mut self, handle: &ViewHandle<V>, f: F) -> T
659 where
660 F: FnOnce(&mut V, &mut RenderContext<V>) -> T,
661 V: View,
662 {
663 handle.update(self.app, |view, cx| {
664 let mut render_cx = RenderContext {
665 app: cx,
666 window_id: handle.window_id(),
667 view_id: handle.id(),
668 view_type: PhantomData,
669 titlebar_height: self.titlebar_height,
670 hovered_region_ids: self.hovered_region_ids.clone(),
671 clicked_region_ids: self.clicked_region_ids.clone(),
672 refreshing: self.refreshing,
673 appearance: self.appearance,
674 };
675 f(view, &mut render_cx)
676 })
677 }
678}
679
680impl<'a> Deref for LayoutContext<'a> {
681 type Target = MutableAppContext;
682
683 fn deref(&self) -> &Self::Target {
684 self.app
685 }
686}
687
688impl<'a> DerefMut for LayoutContext<'a> {
689 fn deref_mut(&mut self) -> &mut Self::Target {
690 self.app
691 }
692}
693
694impl<'a> ReadView for LayoutContext<'a> {
695 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
696 self.app.read_view(handle)
697 }
698}
699
700impl<'a> ReadModel for LayoutContext<'a> {
701 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
702 self.app.read_model(handle)
703 }
704}
705
706impl<'a> UpgradeModelHandle for LayoutContext<'a> {
707 fn upgrade_model_handle<T: Entity>(
708 &self,
709 handle: &WeakModelHandle<T>,
710 ) -> Option<ModelHandle<T>> {
711 self.app.upgrade_model_handle(handle)
712 }
713
714 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
715 self.app.model_handle_is_upgradable(handle)
716 }
717
718 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
719 self.app.upgrade_any_model_handle(handle)
720 }
721}
722
723impl<'a> UpgradeViewHandle for LayoutContext<'a> {
724 fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
725 self.app.upgrade_view_handle(handle)
726 }
727
728 fn upgrade_any_view_handle(&self, handle: &crate::AnyWeakViewHandle) -> Option<AnyViewHandle> {
729 self.app.upgrade_any_view_handle(handle)
730 }
731}
732
733pub struct PaintContext<'a> {
734 rendered_views: &'a mut HashMap<usize, ElementBox>,
735 view_stack: Vec<usize>,
736 pub window_size: Vector2F,
737 pub scene: &'a mut SceneBuilder,
738 pub font_cache: &'a FontCache,
739 pub text_layout_cache: &'a TextLayoutCache,
740 pub app: &'a AppContext,
741}
742
743impl<'a> PaintContext<'a> {
744 fn paint(&mut self, view_id: usize, origin: Vector2F, visible_bounds: RectF) {
745 if let Some(mut tree) = self.rendered_views.remove(&view_id) {
746 self.view_stack.push(view_id);
747 tree.paint(origin, visible_bounds, self);
748 self.rendered_views.insert(view_id, tree);
749 self.view_stack.pop();
750 }
751 }
752
753 #[inline]
754 pub fn paint_stacking_context<F>(
755 &mut self,
756 clip_bounds: Option<RectF>,
757 z_index: Option<usize>,
758 f: F,
759 ) where
760 F: FnOnce(&mut Self),
761 {
762 self.scene.push_stacking_context(clip_bounds, z_index);
763 f(self);
764 self.scene.pop_stacking_context();
765 }
766
767 #[inline]
768 pub fn paint_layer<F>(&mut self, clip_bounds: Option<RectF>, f: F)
769 where
770 F: FnOnce(&mut Self),
771 {
772 self.scene.push_layer(clip_bounds);
773 f(self);
774 self.scene.pop_layer();
775 }
776
777 pub fn current_view_id(&self) -> usize {
778 *self.view_stack.last().unwrap()
779 }
780}
781
782impl<'a> Deref for PaintContext<'a> {
783 type Target = AppContext;
784
785 fn deref(&self) -> &Self::Target {
786 self.app
787 }
788}
789
790pub struct EventContext<'a> {
791 pub font_cache: &'a FontCache,
792 pub text_layout_cache: &'a TextLayoutCache,
793 pub app: &'a mut MutableAppContext,
794 pub window_id: usize,
795 pub notify_count: usize,
796 view_stack: Vec<usize>,
797 handled: bool,
798 notified_views: &'a mut HashSet<usize>,
799}
800
801impl<'a> EventContext<'a> {
802 fn with_current_view<F, T>(&mut self, view_id: usize, f: F) -> T
803 where
804 F: FnOnce(&mut Self) -> T,
805 {
806 self.view_stack.push(view_id);
807 let result = f(self);
808 self.view_stack.pop();
809 result
810 }
811
812 pub fn window_id(&self) -> usize {
813 self.window_id
814 }
815
816 pub fn view_id(&self) -> Option<usize> {
817 self.view_stack.last().copied()
818 }
819
820 pub fn is_parent_view_focused(&self) -> bool {
821 if let Some(parent_view_id) = self.view_stack.last() {
822 self.app.focused_view_id(self.window_id) == Some(*parent_view_id)
823 } else {
824 false
825 }
826 }
827
828 pub fn focus_parent_view(&mut self) {
829 if let Some(parent_view_id) = self.view_stack.last() {
830 self.app.focus(self.window_id, Some(*parent_view_id))
831 }
832 }
833
834 pub fn dispatch_any_action(&mut self, action: Box<dyn Action>) {
835 self.app
836 .dispatch_any_action_at(self.window_id, *self.view_stack.last().unwrap(), action)
837 }
838
839 pub fn dispatch_action<A: Action>(&mut self, action: A) {
840 self.dispatch_any_action(Box::new(action));
841 }
842
843 pub fn notify(&mut self) {
844 self.notify_count += 1;
845 if let Some(view_id) = self.view_stack.last() {
846 self.notified_views.insert(*view_id);
847 }
848 }
849
850 pub fn notify_count(&self) -> usize {
851 self.notify_count
852 }
853
854 pub fn propagate_event(&mut self) {
855 self.handled = false;
856 }
857}
858
859impl<'a> Deref for EventContext<'a> {
860 type Target = MutableAppContext;
861
862 fn deref(&self) -> &Self::Target {
863 self.app
864 }
865}
866
867impl<'a> DerefMut for EventContext<'a> {
868 fn deref_mut(&mut self) -> &mut Self::Target {
869 self.app
870 }
871}
872
873pub struct MeasurementContext<'a> {
874 app: &'a AppContext,
875 rendered_views: &'a HashMap<usize, ElementBox>,
876 pub window_id: usize,
877}
878
879impl<'a> Deref for MeasurementContext<'a> {
880 type Target = AppContext;
881
882 fn deref(&self) -> &Self::Target {
883 self.app
884 }
885}
886
887impl<'a> MeasurementContext<'a> {
888 fn rect_for_text_range(&self, view_id: usize, range_utf16: Range<usize>) -> Option<RectF> {
889 let element = self.rendered_views.get(&view_id)?;
890 element.rect_for_text_range(range_utf16, self)
891 }
892}
893
894pub struct DebugContext<'a> {
895 rendered_views: &'a HashMap<usize, ElementBox>,
896 pub font_cache: &'a FontCache,
897 pub app: &'a AppContext,
898}
899
900#[derive(Clone, Copy, Debug, Default, Eq, PartialEq)]
901pub enum Axis {
902 #[default]
903 Horizontal,
904 Vertical,
905}
906
907impl Axis {
908 pub fn invert(self) -> Self {
909 match self {
910 Self::Horizontal => Self::Vertical,
911 Self::Vertical => Self::Horizontal,
912 }
913 }
914
915 pub fn component(&self, point: Vector2F) -> f32 {
916 match self {
917 Self::Horizontal => point.x(),
918 Self::Vertical => point.y(),
919 }
920 }
921}
922
923impl ToJson for Axis {
924 fn to_json(&self) -> serde_json::Value {
925 match self {
926 Axis::Horizontal => json!("horizontal"),
927 Axis::Vertical => json!("vertical"),
928 }
929 }
930}
931
932impl Bind for Axis {
933 fn bind(&self, statement: &Statement, start_index: i32) -> anyhow::Result<i32> {
934 match self {
935 Axis::Horizontal => "Horizontal",
936 Axis::Vertical => "Vertical",
937 }
938 .bind(statement, start_index)
939 }
940}
941
942impl Column for Axis {
943 fn column(statement: &mut Statement, start_index: i32) -> anyhow::Result<(Self, i32)> {
944 String::column(statement, start_index).and_then(|(axis_text, next_index)| {
945 Ok((
946 match axis_text.as_str() {
947 "Horizontal" => Axis::Horizontal,
948 "Vertical" => Axis::Vertical,
949 _ => bail!("Stored serialized item kind is incorrect"),
950 },
951 next_index,
952 ))
953 })
954 }
955}
956
957pub trait Vector2FExt {
958 fn along(self, axis: Axis) -> f32;
959}
960
961impl Vector2FExt for Vector2F {
962 fn along(self, axis: Axis) -> f32 {
963 match axis {
964 Axis::Horizontal => self.x(),
965 Axis::Vertical => self.y(),
966 }
967 }
968}
969
970#[derive(Copy, Clone, Debug)]
971pub struct SizeConstraint {
972 pub min: Vector2F,
973 pub max: Vector2F,
974}
975
976impl SizeConstraint {
977 pub fn new(min: Vector2F, max: Vector2F) -> Self {
978 Self { min, max }
979 }
980
981 pub fn strict(size: Vector2F) -> Self {
982 Self {
983 min: size,
984 max: size,
985 }
986 }
987
988 pub fn strict_along(axis: Axis, max: f32) -> Self {
989 match axis {
990 Axis::Horizontal => Self {
991 min: vec2f(max, 0.0),
992 max: vec2f(max, f32::INFINITY),
993 },
994 Axis::Vertical => Self {
995 min: vec2f(0.0, max),
996 max: vec2f(f32::INFINITY, max),
997 },
998 }
999 }
1000
1001 pub fn max_along(&self, axis: Axis) -> f32 {
1002 match axis {
1003 Axis::Horizontal => self.max.x(),
1004 Axis::Vertical => self.max.y(),
1005 }
1006 }
1007
1008 pub fn min_along(&self, axis: Axis) -> f32 {
1009 match axis {
1010 Axis::Horizontal => self.min.x(),
1011 Axis::Vertical => self.min.y(),
1012 }
1013 }
1014
1015 pub fn constrain(&self, size: Vector2F) -> Vector2F {
1016 vec2f(
1017 size.x().min(self.max.x()).max(self.min.x()),
1018 size.y().min(self.max.y()).max(self.min.y()),
1019 )
1020 }
1021}
1022
1023impl Default for SizeConstraint {
1024 fn default() -> Self {
1025 SizeConstraint {
1026 min: Vector2F::zero(),
1027 max: Vector2F::splat(f32::INFINITY),
1028 }
1029 }
1030}
1031
1032impl ToJson for SizeConstraint {
1033 fn to_json(&self) -> serde_json::Value {
1034 json!({
1035 "min": self.min.to_json(),
1036 "max": self.max.to_json(),
1037 })
1038 }
1039}
1040
1041pub struct ChildView {
1042 view: AnyWeakViewHandle,
1043 view_name: &'static str,
1044}
1045
1046impl ChildView {
1047 pub fn new(view: impl Into<AnyViewHandle>, cx: &AppContext) -> Self {
1048 let view = view.into();
1049 let view_name = cx.view_ui_name(view.window_id(), view.id()).unwrap();
1050 Self {
1051 view: view.downgrade(),
1052 view_name,
1053 }
1054 }
1055}
1056
1057impl Element for ChildView {
1058 type LayoutState = bool;
1059 type PaintState = ();
1060
1061 fn layout(
1062 &mut self,
1063 constraint: SizeConstraint,
1064 cx: &mut LayoutContext,
1065 ) -> (Vector2F, Self::LayoutState) {
1066 if cx.rendered_views.contains_key(&self.view.id()) {
1067 let size = cx.layout(self.view.id(), constraint);
1068 (size, true)
1069 } else {
1070 log::error!(
1071 "layout called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1072 self.view.id(),
1073 self.view_name
1074 );
1075 (Vector2F::zero(), false)
1076 }
1077 }
1078
1079 fn paint(
1080 &mut self,
1081 bounds: RectF,
1082 visible_bounds: RectF,
1083 view_is_valid: &mut Self::LayoutState,
1084 cx: &mut PaintContext,
1085 ) {
1086 if *view_is_valid {
1087 cx.paint(self.view.id(), bounds.origin(), visible_bounds);
1088 } else {
1089 log::error!(
1090 "paint called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1091 self.view.id(),
1092 self.view_name
1093 );
1094 }
1095 }
1096
1097 fn rect_for_text_range(
1098 &self,
1099 range_utf16: Range<usize>,
1100 _: RectF,
1101 _: RectF,
1102 view_is_valid: &Self::LayoutState,
1103 _: &Self::PaintState,
1104 cx: &MeasurementContext,
1105 ) -> Option<RectF> {
1106 if *view_is_valid {
1107 cx.rect_for_text_range(self.view.id(), range_utf16)
1108 } else {
1109 log::error!(
1110 "rect_for_text_range called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1111 self.view.id(),
1112 self.view_name
1113 );
1114 None
1115 }
1116 }
1117
1118 fn debug(
1119 &self,
1120 bounds: RectF,
1121 _: &Self::LayoutState,
1122 _: &Self::PaintState,
1123 cx: &DebugContext,
1124 ) -> serde_json::Value {
1125 json!({
1126 "type": "ChildView",
1127 "view_id": self.view.id(),
1128 "bounds": bounds.to_json(),
1129 "view": if let Some(view) = self.view.upgrade(cx.app) {
1130 view.debug_json(cx.app)
1131 } else {
1132 json!(null)
1133 },
1134 "child": if let Some(view) = cx.rendered_views.get(&self.view.id()) {
1135 view.debug(cx)
1136 } else {
1137 json!(null)
1138 }
1139 })
1140 }
1141}