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