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