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<MouseMovedEvent>,
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 mouse_up_region = None;
241 let mut clicked_region = None;
242 let mut dragged_region = None;
243
244 match &event {
245 Event::MouseDown(
246 e @ MouseButtonEvent {
247 position, button, ..
248 },
249 ) => {
250 let mut hit = false;
251 for (region, _) in self.mouse_regions.iter().rev() {
252 if region.bounds.contains_point(*position) {
253 if !hit {
254 hit = true;
255 invalidated_views.push(region.view_id);
256 mouse_down_region =
257 Some((region.clone(), MouseRegionEvent::Down(e.clone())));
258 self.clicked_region = Some(region.clone());
259 self.prev_drag_position = Some(*position);
260 }
261 } else if let Some(handler) = region
262 .handlers
263 .get(&(MouseRegionEvent::down_out_disc(), Some(*button)))
264 {
265 mouse_down_out_handlers.push((
266 handler,
267 region.view_id,
268 MouseRegionEvent::DownOut(e.clone()),
269 ));
270 }
271 }
272 }
273
274 &Event::MouseUp(
275 e @ MouseButtonEvent {
276 position, button, ..
277 },
278 ) => {
279 self.prev_drag_position.take();
280 if let Some(region) = self.clicked_region.take() {
281 invalidated_views.push(region.view_id);
282 if region.bounds.contains_point(position) {
283 clicked_region = Some((region, MouseRegionEvent::Click(e.clone())));
284 }
285 }
286
287 for (region, _) in self.mouse_regions.iter().rev() {
288 if region.bounds.contains_point(position) {
289 invalidated_views.push(region.view_id);
290 mouse_up_region =
291 Some((region.clone(), MouseRegionEvent::Up(e.clone())));
292 break;
293 }
294 }
295
296 if let Some(moved) = &mut self.last_mouse_moved_event {
297 if moved.pressed_button == Some(button) {
298 moved.pressed_button = None;
299 }
300 }
301 }
302
303 Event::MouseMoved(e @ MouseMovedEvent { position, .. }) => {
304 if let Some((clicked_region, prev_drag_position)) = self
305 .clicked_region
306 .as_ref()
307 .zip(self.prev_drag_position.as_mut())
308 {
309 dragged_region = Some((
310 clicked_region.clone(),
311 MouseRegionEvent::Drag(*prev_drag_position, *e),
312 ));
313 *prev_drag_position = *position;
314 }
315
316 for (region, _) in self.mouse_regions.iter().rev() {
317 if region.bounds.contains_point(*position) {
318 invalidated_views.push(region.view_id);
319 mouse_moved_region =
320 Some((region.clone(), MouseRegionEvent::Move(e.clone())));
321 break;
322 }
323 }
324
325 self.last_mouse_moved_event = Some(e.clone());
326 }
327
328 _ => {}
329 }
330
331 let (mut handled, mut event_cx) = if let Event::MouseMoved(e) = &event {
332 self.handle_hover_events(e, &mut invalidated_views, cx)
333 } else {
334 (false, self.build_event_context(cx))
335 };
336
337 for (handler, view_id, region_event) in mouse_down_out_handlers {
338 event_cx.with_current_view(view_id, |event_cx| handler(region_event, event_cx))
339 }
340
341 if let Some((mouse_down_region, region_event)) = mouse_down_region {
342 handled = true;
343 if let Some(mouse_down_callback) =
344 mouse_down_region.handlers.get(®ion_event.handler_key())
345 {
346 event_cx.with_current_view(mouse_down_region.view_id, |event_cx| {
347 mouse_down_callback(region_event, event_cx);
348 })
349 }
350 }
351
352 if let Some((move_moved_region, region_event)) = mouse_moved_region {
353 handled = true;
354 if let Some(mouse_moved_callback) =
355 move_moved_region.handlers.get(®ion_event.handler_key())
356 {
357 event_cx.with_current_view(move_moved_region.view_id, |event_cx| {
358 mouse_moved_callback(region_event, event_cx);
359 })
360 }
361 }
362
363 if let Some((mouse_up_region, region_event)) = mouse_up_region {
364 handled = true;
365 if let Some(mouse_up_callback) =
366 mouse_up_region.handlers.get(®ion_event.handler_key())
367 {
368 event_cx.with_current_view(mouse_up_region.view_id, |event_cx| {
369 mouse_up_callback(region_event, event_cx);
370 })
371 }
372 }
373
374 if let Some((clicked_region, region_event)) = clicked_region {
375 handled = true;
376 if let Some(click_callback) =
377 clicked_region.handlers.get(®ion_event.handler_key())
378 {
379 event_cx.with_current_view(clicked_region.view_id, |event_cx| {
380 click_callback(region_event, event_cx);
381 })
382 }
383 }
384
385 if let Some((dragged_region, region_event)) = dragged_region {
386 handled = true;
387 if let Some(drag_callback) =
388 dragged_region.handlers.get(®ion_event.handler_key())
389 {
390 event_cx.with_current_view(dragged_region.view_id, |event_cx| {
391 drag_callback(region_event, event_cx);
392 })
393 }
394 }
395
396 if !handled {
397 handled = event_cx.dispatch_event(root_view_id, &event);
398 }
399
400 invalidated_views.extend(event_cx.invalidated_views);
401
402 for view_id in invalidated_views {
403 cx.notify_view(self.window_id, view_id);
404 }
405
406 handled
407 } else {
408 false
409 }
410 }
411
412 fn handle_hover_events<'a>(
413 &'a mut self,
414 e @ MouseMovedEvent {
415 position,
416 pressed_button,
417 ..
418 }: &MouseMovedEvent,
419 invalidated_views: &mut Vec<usize>,
420 cx: &'a mut MutableAppContext,
421 ) -> (bool, EventContext<'a>) {
422 let mut hover_regions = Vec::new();
423
424 if pressed_button.is_none() {
425 let mut style_to_assign = CursorStyle::Arrow;
426 for region in self.cursor_regions.iter().rev() {
427 if region.bounds.contains_point(*position) {
428 style_to_assign = region.style;
429 break;
430 }
431 }
432 cx.platform().set_cursor_style(style_to_assign);
433
434 let mut hover_depth = None;
435 for (region, depth) in self.mouse_regions.iter().rev() {
436 if region.bounds.contains_point(*position)
437 && hover_depth.map_or(true, |hover_depth| hover_depth == *depth)
438 {
439 hover_depth = Some(*depth);
440 if let Some(region_id) = region.id() {
441 if !self.hovered_region_ids.contains(®ion_id) {
442 invalidated_views.push(region.view_id);
443 hover_regions.push((region.clone(), MouseRegionEvent::Hover(true, *e)));
444 self.hovered_region_ids.insert(region_id);
445 }
446 }
447 } else if let Some(region_id) = region.id() {
448 if self.hovered_region_ids.contains(®ion_id) {
449 invalidated_views.push(region.view_id);
450 hover_regions.push((region.clone(), MouseRegionEvent::Hover(false, *e)));
451 self.hovered_region_ids.remove(®ion_id);
452 }
453 }
454 }
455 }
456
457 let mut event_cx = self.build_event_context(cx);
458 let mut handled = false;
459
460 for (hover_region, region_event) in hover_regions {
461 handled = true;
462 if let Some(hover_callback) = hover_region.handlers.get(®ion_event.handler_key()) {
463 event_cx.with_current_view(hover_region.view_id, |event_cx| {
464 hover_callback(region_event, event_cx);
465 })
466 }
467 }
468
469 (handled, event_cx)
470 }
471
472 pub fn build_event_context<'a>(
473 &'a mut self,
474 cx: &'a mut MutableAppContext,
475 ) -> EventContext<'a> {
476 EventContext {
477 rendered_views: &mut self.rendered_views,
478 font_cache: &self.font_cache,
479 text_layout_cache: &self.text_layout_cache,
480 view_stack: Default::default(),
481 invalidated_views: Default::default(),
482 notify_count: 0,
483 window_id: self.window_id,
484 app: cx,
485 }
486 }
487
488 pub fn debug_elements(&self, cx: &AppContext) -> Option<json::Value> {
489 let view = cx.root_view(self.window_id)?;
490 Some(json!({
491 "root_view": view.debug_json(cx),
492 "root_element": self.rendered_views.get(&view.id())
493 .map(|root_element| {
494 root_element.debug(&DebugContext {
495 rendered_views: &self.rendered_views,
496 font_cache: &self.font_cache,
497 app: cx,
498 })
499 })
500 }))
501 }
502}
503
504pub struct LayoutContext<'a> {
505 window_id: usize,
506 rendered_views: &'a mut HashMap<usize, ElementBox>,
507 view_stack: Vec<usize>,
508 pub font_cache: &'a Arc<FontCache>,
509 pub font_system: Arc<dyn FontSystem>,
510 pub text_layout_cache: &'a TextLayoutCache,
511 pub asset_cache: &'a AssetCache,
512 pub app: &'a mut MutableAppContext,
513 pub refreshing: bool,
514 pub window_size: Vector2F,
515 titlebar_height: f32,
516 hovered_region_ids: HashSet<MouseRegionId>,
517 clicked_region_id: Option<MouseRegionId>,
518 right_clicked_region_id: Option<MouseRegionId>,
519}
520
521impl<'a> LayoutContext<'a> {
522 pub(crate) fn keystrokes_for_action(
523 &self,
524 action: &dyn Action,
525 ) -> Option<SmallVec<[Keystroke; 2]>> {
526 self.app
527 .keystrokes_for_action(self.window_id, &self.view_stack, action)
528 }
529
530 fn layout(&mut self, view_id: usize, constraint: SizeConstraint) -> Vector2F {
531 let print_error = |view_id| {
532 format!(
533 "{} with id {}",
534 self.app.name_for_view(self.window_id, view_id).unwrap(),
535 view_id,
536 )
537 };
538 match (
539 self.view_stack.last(),
540 self.app.parents.get(&(self.window_id, view_id)),
541 ) {
542 (Some(layout_parent), Some(ParentId::View(app_parent))) => {
543 if layout_parent != app_parent {
544 panic!(
545 "View {} was laid out with parent {} when it was constructed with parent {}",
546 print_error(view_id),
547 print_error(*layout_parent),
548 print_error(*app_parent))
549 }
550 }
551 (None, Some(ParentId::View(app_parent))) => panic!(
552 "View {} was laid out without a parent when it was constructed with parent {}",
553 print_error(view_id),
554 print_error(*app_parent)
555 ),
556 (Some(layout_parent), Some(ParentId::Root)) => panic!(
557 "View {} was laid out with parent {} when it was constructed as a window root",
558 print_error(view_id),
559 print_error(*layout_parent),
560 ),
561 (_, None) => panic!(
562 "View {} did not have a registered parent in the app context",
563 print_error(view_id),
564 ),
565 _ => {}
566 }
567
568 self.view_stack.push(view_id);
569 let mut rendered_view = self.rendered_views.remove(&view_id).unwrap();
570 let size = rendered_view.layout(constraint, self);
571 self.rendered_views.insert(view_id, rendered_view);
572 self.view_stack.pop();
573 size
574 }
575
576 pub fn render<F, V, T>(&mut self, handle: &ViewHandle<V>, f: F) -> T
577 where
578 F: FnOnce(&mut V, &mut RenderContext<V>) -> T,
579 V: View,
580 {
581 handle.update(self.app, |view, cx| {
582 let mut render_cx = RenderContext {
583 app: cx,
584 window_id: handle.window_id(),
585 view_id: handle.id(),
586 view_type: PhantomData,
587 titlebar_height: self.titlebar_height,
588 hovered_region_ids: self.hovered_region_ids.clone(),
589 clicked_region_id: self.clicked_region_id,
590 right_clicked_region_id: self.right_clicked_region_id,
591 refreshing: self.refreshing,
592 };
593 f(view, &mut render_cx)
594 })
595 }
596}
597
598impl<'a> Deref for LayoutContext<'a> {
599 type Target = MutableAppContext;
600
601 fn deref(&self) -> &Self::Target {
602 self.app
603 }
604}
605
606impl<'a> DerefMut for LayoutContext<'a> {
607 fn deref_mut(&mut self) -> &mut Self::Target {
608 self.app
609 }
610}
611
612impl<'a> ReadView for LayoutContext<'a> {
613 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
614 self.app.read_view(handle)
615 }
616}
617
618impl<'a> ReadModel for LayoutContext<'a> {
619 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
620 self.app.read_model(handle)
621 }
622}
623
624impl<'a> UpgradeModelHandle for LayoutContext<'a> {
625 fn upgrade_model_handle<T: Entity>(
626 &self,
627 handle: &WeakModelHandle<T>,
628 ) -> Option<ModelHandle<T>> {
629 self.app.upgrade_model_handle(handle)
630 }
631
632 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
633 self.app.model_handle_is_upgradable(handle)
634 }
635
636 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
637 self.app.upgrade_any_model_handle(handle)
638 }
639}
640
641impl<'a> UpgradeViewHandle for LayoutContext<'a> {
642 fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
643 self.app.upgrade_view_handle(handle)
644 }
645
646 fn upgrade_any_view_handle(&self, handle: &crate::AnyWeakViewHandle) -> Option<AnyViewHandle> {
647 self.app.upgrade_any_view_handle(handle)
648 }
649}
650
651pub struct PaintContext<'a> {
652 rendered_views: &'a mut HashMap<usize, ElementBox>,
653 view_stack: Vec<usize>,
654 pub window_size: Vector2F,
655 pub scene: &'a mut Scene,
656 pub font_cache: &'a FontCache,
657 pub text_layout_cache: &'a TextLayoutCache,
658 pub app: &'a AppContext,
659}
660
661impl<'a> PaintContext<'a> {
662 fn paint(&mut self, view_id: usize, origin: Vector2F, visible_bounds: RectF) {
663 if let Some(mut tree) = self.rendered_views.remove(&view_id) {
664 self.view_stack.push(view_id);
665 tree.paint(origin, visible_bounds, self);
666 self.rendered_views.insert(view_id, tree);
667 self.view_stack.pop();
668 }
669 }
670
671 #[inline]
672 pub fn paint_layer<F>(&mut self, clip_bounds: Option<RectF>, f: F)
673 where
674 F: FnOnce(&mut Self),
675 {
676 self.scene.push_layer(clip_bounds);
677 f(self);
678 self.scene.pop_layer();
679 }
680
681 pub fn current_view_id(&self) -> usize {
682 *self.view_stack.last().unwrap()
683 }
684}
685
686impl<'a> Deref for PaintContext<'a> {
687 type Target = AppContext;
688
689 fn deref(&self) -> &Self::Target {
690 self.app
691 }
692}
693
694pub struct EventContext<'a> {
695 rendered_views: &'a mut HashMap<usize, ElementBox>,
696 pub font_cache: &'a FontCache,
697 pub text_layout_cache: &'a TextLayoutCache,
698 pub app: &'a mut MutableAppContext,
699 pub window_id: usize,
700 pub notify_count: usize,
701 view_stack: Vec<usize>,
702 invalidated_views: HashSet<usize>,
703}
704
705impl<'a> EventContext<'a> {
706 fn dispatch_event(&mut self, view_id: usize, event: &Event) -> bool {
707 if let Some(mut element) = self.rendered_views.remove(&view_id) {
708 let result =
709 self.with_current_view(view_id, |this| element.dispatch_event(event, this));
710 self.rendered_views.insert(view_id, element);
711 result
712 } else {
713 false
714 }
715 }
716
717 fn with_current_view<F, T>(&mut self, view_id: usize, f: F) -> T
718 where
719 F: FnOnce(&mut Self) -> T,
720 {
721 self.view_stack.push(view_id);
722 let result = f(self);
723 self.view_stack.pop();
724 result
725 }
726
727 pub fn window_id(&self) -> usize {
728 self.window_id
729 }
730
731 pub fn view_id(&self) -> Option<usize> {
732 self.view_stack.last().copied()
733 }
734
735 pub fn is_parent_view_focused(&self) -> bool {
736 if let Some(parent_view_id) = self.view_stack.last() {
737 self.app.focused_view_id(self.window_id) == Some(*parent_view_id)
738 } else {
739 false
740 }
741 }
742
743 pub fn focus_parent_view(&mut self) {
744 if let Some(parent_view_id) = self.view_stack.last() {
745 self.app.focus(self.window_id, Some(*parent_view_id))
746 }
747 }
748
749 pub fn dispatch_any_action(&mut self, action: Box<dyn Action>) {
750 self.app
751 .dispatch_any_action_at(self.window_id, *self.view_stack.last().unwrap(), action)
752 }
753
754 pub fn dispatch_action<A: Action>(&mut self, action: A) {
755 self.dispatch_any_action(Box::new(action));
756 }
757
758 pub fn notify(&mut self) {
759 self.notify_count += 1;
760 if let Some(view_id) = self.view_stack.last() {
761 self.invalidated_views.insert(*view_id);
762 }
763 }
764
765 pub fn notify_count(&self) -> usize {
766 self.notify_count
767 }
768}
769
770impl<'a> Deref for EventContext<'a> {
771 type Target = MutableAppContext;
772
773 fn deref(&self) -> &Self::Target {
774 self.app
775 }
776}
777
778impl<'a> DerefMut for EventContext<'a> {
779 fn deref_mut(&mut self) -> &mut Self::Target {
780 self.app
781 }
782}
783
784pub struct MeasurementContext<'a> {
785 app: &'a AppContext,
786 rendered_views: &'a HashMap<usize, ElementBox>,
787 pub window_id: usize,
788}
789
790impl<'a> Deref for MeasurementContext<'a> {
791 type Target = AppContext;
792
793 fn deref(&self) -> &Self::Target {
794 self.app
795 }
796}
797
798impl<'a> MeasurementContext<'a> {
799 fn rect_for_text_range(&self, view_id: usize, range_utf16: Range<usize>) -> Option<RectF> {
800 let element = self.rendered_views.get(&view_id)?;
801 element.rect_for_text_range(range_utf16, self)
802 }
803}
804
805pub struct DebugContext<'a> {
806 rendered_views: &'a HashMap<usize, ElementBox>,
807 pub font_cache: &'a FontCache,
808 pub app: &'a AppContext,
809}
810
811#[derive(Clone, Copy, Debug, Eq, PartialEq)]
812pub enum Axis {
813 Horizontal,
814 Vertical,
815}
816
817impl Axis {
818 pub fn invert(self) -> Self {
819 match self {
820 Self::Horizontal => Self::Vertical,
821 Self::Vertical => Self::Horizontal,
822 }
823 }
824}
825
826impl ToJson for Axis {
827 fn to_json(&self) -> serde_json::Value {
828 match self {
829 Axis::Horizontal => json!("horizontal"),
830 Axis::Vertical => json!("vertical"),
831 }
832 }
833}
834
835pub trait Vector2FExt {
836 fn along(self, axis: Axis) -> f32;
837}
838
839impl Vector2FExt for Vector2F {
840 fn along(self, axis: Axis) -> f32 {
841 match axis {
842 Axis::Horizontal => self.x(),
843 Axis::Vertical => self.y(),
844 }
845 }
846}
847
848#[derive(Copy, Clone, Debug)]
849pub struct SizeConstraint {
850 pub min: Vector2F,
851 pub max: Vector2F,
852}
853
854impl SizeConstraint {
855 pub fn new(min: Vector2F, max: Vector2F) -> Self {
856 Self { min, max }
857 }
858
859 pub fn strict(size: Vector2F) -> Self {
860 Self {
861 min: size,
862 max: size,
863 }
864 }
865
866 pub fn strict_along(axis: Axis, max: f32) -> Self {
867 match axis {
868 Axis::Horizontal => Self {
869 min: vec2f(max, 0.0),
870 max: vec2f(max, f32::INFINITY),
871 },
872 Axis::Vertical => Self {
873 min: vec2f(0.0, max),
874 max: vec2f(f32::INFINITY, max),
875 },
876 }
877 }
878
879 pub fn max_along(&self, axis: Axis) -> f32 {
880 match axis {
881 Axis::Horizontal => self.max.x(),
882 Axis::Vertical => self.max.y(),
883 }
884 }
885
886 pub fn min_along(&self, axis: Axis) -> f32 {
887 match axis {
888 Axis::Horizontal => self.min.x(),
889 Axis::Vertical => self.min.y(),
890 }
891 }
892
893 pub fn constrain(&self, size: Vector2F) -> Vector2F {
894 vec2f(
895 size.x().min(self.max.x()).max(self.min.x()),
896 size.y().min(self.max.y()).max(self.min.y()),
897 )
898 }
899}
900
901impl Default for SizeConstraint {
902 fn default() -> Self {
903 SizeConstraint {
904 min: Vector2F::zero(),
905 max: Vector2F::splat(f32::INFINITY),
906 }
907 }
908}
909
910impl ToJson for SizeConstraint {
911 fn to_json(&self) -> serde_json::Value {
912 json!({
913 "min": self.min.to_json(),
914 "max": self.max.to_json(),
915 })
916 }
917}
918
919pub struct ChildView {
920 view: AnyViewHandle,
921}
922
923impl ChildView {
924 pub fn new(view: impl Into<AnyViewHandle>) -> Self {
925 Self { view: view.into() }
926 }
927}
928
929impl Element for ChildView {
930 type LayoutState = ();
931 type PaintState = ();
932
933 fn layout(
934 &mut self,
935 constraint: SizeConstraint,
936 cx: &mut LayoutContext,
937 ) -> (Vector2F, Self::LayoutState) {
938 let size = cx.layout(self.view.id(), constraint);
939 (size, ())
940 }
941
942 fn paint(
943 &mut self,
944 bounds: RectF,
945 visible_bounds: RectF,
946 _: &mut Self::LayoutState,
947 cx: &mut PaintContext,
948 ) -> Self::PaintState {
949 cx.paint(self.view.id(), bounds.origin(), visible_bounds);
950 }
951
952 fn dispatch_event(
953 &mut self,
954 event: &Event,
955 _: RectF,
956 _: RectF,
957 _: &mut Self::LayoutState,
958 _: &mut Self::PaintState,
959 cx: &mut EventContext,
960 ) -> bool {
961 cx.dispatch_event(self.view.id(), event)
962 }
963
964 fn rect_for_text_range(
965 &self,
966 range_utf16: Range<usize>,
967 _: RectF,
968 _: RectF,
969 _: &Self::LayoutState,
970 _: &Self::PaintState,
971 cx: &MeasurementContext,
972 ) -> Option<RectF> {
973 cx.rect_for_text_range(self.view.id(), range_utf16)
974 }
975
976 fn debug(
977 &self,
978 bounds: RectF,
979 _: &Self::LayoutState,
980 _: &Self::PaintState,
981 cx: &DebugContext,
982 ) -> serde_json::Value {
983 json!({
984 "type": "ChildView",
985 "view_id": self.view.id(),
986 "bounds": bounds.to_json(),
987 "view": self.view.debug_json(cx.app),
988 "child": if let Some(view) = cx.rendered_views.get(&self.view.id()) {
989 view.debug(cx)
990 } else {
991 json!(null)
992 }
993 })
994 }
995}