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
249 // If there is already clicked_button stored, don't replace it.
250 if self.clicked_button.is_none() {
251 self.clicked_regions = self
252 .mouse_regions
253 .iter()
254 .filter_map(|(region, _)| {
255 region
256 .bounds
257 .contains_point(e.position)
258 .then(|| region.clone())
259 })
260 .collect();
261 self.clicked_button = Some(e.button);
262 }
263
264 events_to_send.push(MouseRegionEvent::Down(DownRegionEvent {
265 region: Default::default(),
266 platform_event: e.clone(),
267 }));
268 events_to_send.push(MouseRegionEvent::DownOut(DownOutRegionEvent {
269 region: Default::default(),
270 platform_event: e.clone(),
271 }));
272 }
273 Event::MouseUp(e) => {
274 // NOTE: The order of event pushes is important! MouseUp events MUST be fired
275 // before click events, and so the UpRegionEvent events need to be pushed before
276 // ClickRegionEvents
277 events_to_send.push(MouseRegionEvent::Up(UpRegionEvent {
278 region: Default::default(),
279 platform_event: e.clone(),
280 }));
281 events_to_send.push(MouseRegionEvent::UpOut(UpOutRegionEvent {
282 region: Default::default(),
283 platform_event: e.clone(),
284 }));
285 events_to_send.push(MouseRegionEvent::Click(ClickRegionEvent {
286 region: Default::default(),
287 platform_event: e.clone(),
288 }));
289 }
290 Event::MouseMoved(
291 e @ MouseMovedEvent {
292 position,
293 pressed_button,
294 ..
295 },
296 ) => {
297 let mut style_to_assign = CursorStyle::Arrow;
298 for region in self.cursor_regions.iter().rev() {
299 if region.bounds.contains_point(*position) {
300 style_to_assign = region.style;
301 break;
302 }
303 }
304 cx.platform().set_cursor_style(style_to_assign);
305
306 if !event_reused {
307 if pressed_button.is_some() {
308 events_to_send.push(MouseRegionEvent::Drag(DragRegionEvent {
309 region: Default::default(),
310 prev_mouse_position: self.mouse_position,
311 platform_event: e.clone(),
312 }));
313 }
314 events_to_send.push(MouseRegionEvent::Move(MoveRegionEvent {
315 region: Default::default(),
316 platform_event: e.clone(),
317 }));
318 }
319
320 events_to_send.push(MouseRegionEvent::Hover(HoverRegionEvent {
321 region: Default::default(),
322 platform_event: e.clone(),
323 started: false,
324 }));
325
326 self.last_mouse_moved_event = Some(event.clone());
327 }
328
329 _ => {}
330 }
331
332 if let Some(position) = event.position() {
333 self.mouse_position = position;
334 }
335
336 let mut invalidated_views: HashSet<usize> = Default::default();
337 let mut any_event_handled = false;
338 // 2. Process the raw mouse events into region events
339 for mut region_event in events_to_send {
340 let mut valid_regions = Vec::new();
341
342 // GPUI elements are arranged by depth but sibling elements can register overlapping
343 // mouse regions. As such, hover events are only fired on overlapping elements which
344 // are at the same depth as the topmost element which overlaps with the mouse.
345
346 match ®ion_event {
347 MouseRegionEvent::Hover(_) => {
348 let mut top_most_depth = None;
349 let mouse_position = self.mouse_position.clone();
350 for (region, depth) in self.mouse_regions.iter().rev() {
351 // Allow mouse regions to appear transparent to hovers
352 if !region.hoverable {
353 continue;
354 }
355
356 let contains_mouse = region.bounds.contains_point(mouse_position);
357
358 if contains_mouse && top_most_depth.is_none() {
359 top_most_depth = Some(depth);
360 }
361
362 if let Some(region_id) = region.id() {
363 // This unwrap relies on short circuiting boolean expressions
364 // The right side of the && is only executed when contains_mouse
365 // is true, and we know above that when contains_mouse is true
366 // top_most_depth is set
367 if contains_mouse && depth == top_most_depth.unwrap() {
368 //Ensure that hover entrance events aren't sent twice
369 if self.hovered_region_ids.insert(region_id) {
370 valid_regions.push(region.clone());
371 invalidated_views.insert(region.view_id);
372 }
373 } else {
374 // Ensure that hover exit events aren't sent twice
375 if self.hovered_region_ids.remove(®ion_id) {
376 valid_regions.push(region.clone());
377 invalidated_views.insert(region.view_id);
378 }
379 }
380 }
381 }
382 }
383 MouseRegionEvent::Click(e) => {
384 // Only raise click events if the released button is the same as the one stored
385 if self
386 .clicked_button
387 .map(|clicked_button| clicked_button == e.button)
388 .unwrap_or(false)
389 {
390 // Clear clicked regions and clicked button
391 let clicked_regions =
392 std::mem::replace(&mut self.clicked_regions, Vec::new());
393 self.clicked_button = None;
394
395 // Find regions which still overlap with the mouse since the last MouseDown happened
396 for clicked_region in clicked_regions.into_iter().rev() {
397 if clicked_region.bounds.contains_point(e.position) {
398 valid_regions.push(clicked_region);
399 }
400 }
401 }
402 }
403 MouseRegionEvent::Drag(_) => {
404 for clicked_region in self.clicked_regions.iter().rev() {
405 valid_regions.push(clicked_region.clone());
406 }
407 }
408
409 MouseRegionEvent::UpOut(_) | MouseRegionEvent::DownOut(_) => {
410 for (mouse_region, _) in self.mouse_regions.iter().rev() {
411 // NOT contains
412 if !mouse_region.bounds.contains_point(self.mouse_position) {
413 valid_regions.push(mouse_region.clone());
414 }
415 }
416 }
417 _ => {
418 for (mouse_region, _) in self.mouse_regions.iter().rev() {
419 // Contains
420 if mouse_region.bounds.contains_point(self.mouse_position) {
421 valid_regions.push(mouse_region.clone());
422 }
423 }
424 }
425 }
426
427 //3. Fire region events
428 let hovered_region_ids = self.hovered_region_ids.clone();
429 for valid_region in valid_regions.into_iter() {
430 region_event.set_region(valid_region.bounds);
431 if let MouseRegionEvent::Hover(e) = &mut region_event {
432 e.started = valid_region
433 .id()
434 .map(|region_id| hovered_region_ids.contains(®ion_id))
435 .unwrap_or(false)
436 }
437
438 if let Some(callback) = valid_region.handlers.get(®ion_event.handler_key()) {
439 invalidated_views.insert(valid_region.view_id);
440
441 let mut event_cx = self.build_event_context(&mut invalidated_views, cx);
442 event_cx.handled = true;
443 event_cx.with_current_view(valid_region.view_id, {
444 let region_event = region_event.clone();
445 |cx| {
446 callback(region_event, cx);
447 }
448 });
449
450 any_event_handled = any_event_handled || event_cx.handled;
451 // For bubbling events, if the event was handled, don't continue dispatching
452 // This only makes sense for local events.
453 if event_cx.handled && region_event.is_capturable() {
454 break;
455 }
456 }
457 }
458 }
459
460 if !any_event_handled && !event_reused {
461 let mut event_cx = self.build_event_context(&mut invalidated_views, cx);
462 any_event_handled = event_cx.dispatch_event(root_view_id, &event);
463 }
464
465 for view_id in invalidated_views {
466 cx.notify_view(self.window_id, view_id);
467 }
468
469 any_event_handled
470 } else {
471 false
472 }
473 }
474
475 pub fn build_event_context<'a>(
476 &'a mut self,
477 invalidated_views: &'a mut HashSet<usize>,
478 cx: &'a mut MutableAppContext,
479 ) -> EventContext<'a> {
480 EventContext {
481 rendered_views: &mut self.rendered_views,
482 font_cache: &self.font_cache,
483 text_layout_cache: &self.text_layout_cache,
484 view_stack: Default::default(),
485 invalidated_views,
486 notify_count: 0,
487 handled: false,
488 window_id: self.window_id,
489 app: cx,
490 }
491 }
492
493 pub fn debug_elements(&self, cx: &AppContext) -> Option<json::Value> {
494 let view = cx.root_view(self.window_id)?;
495 Some(json!({
496 "root_view": view.debug_json(cx),
497 "root_element": self.rendered_views.get(&view.id())
498 .map(|root_element| {
499 root_element.debug(&DebugContext {
500 rendered_views: &self.rendered_views,
501 font_cache: &self.font_cache,
502 app: cx,
503 })
504 })
505 }))
506 }
507}
508
509pub struct LayoutContext<'a> {
510 window_id: usize,
511 rendered_views: &'a mut HashMap<usize, ElementBox>,
512 view_stack: Vec<usize>,
513 pub font_cache: &'a Arc<FontCache>,
514 pub font_system: Arc<dyn FontSystem>,
515 pub text_layout_cache: &'a TextLayoutCache,
516 pub asset_cache: &'a AssetCache,
517 pub app: &'a mut MutableAppContext,
518 pub refreshing: bool,
519 pub window_size: Vector2F,
520 titlebar_height: f32,
521 hovered_region_ids: HashSet<MouseRegionId>,
522 clicked_region_ids: Option<(Vec<MouseRegionId>, MouseButton)>,
523}
524
525impl<'a> LayoutContext<'a> {
526 pub(crate) fn keystrokes_for_action(
527 &self,
528 action: &dyn Action,
529 ) -> Option<SmallVec<[Keystroke; 2]>> {
530 self.app
531 .keystrokes_for_action(self.window_id, &self.view_stack, action)
532 }
533
534 fn layout(&mut self, view_id: usize, constraint: SizeConstraint) -> Vector2F {
535 let print_error = |view_id| {
536 format!(
537 "{} with id {}",
538 self.app.name_for_view(self.window_id, view_id).unwrap(),
539 view_id,
540 )
541 };
542 match (
543 self.view_stack.last(),
544 self.app.parents.get(&(self.window_id, view_id)),
545 ) {
546 (Some(layout_parent), Some(ParentId::View(app_parent))) => {
547 if layout_parent != app_parent {
548 panic!(
549 "View {} was laid out with parent {} when it was constructed with parent {}",
550 print_error(view_id),
551 print_error(*layout_parent),
552 print_error(*app_parent))
553 }
554 }
555 (None, Some(ParentId::View(app_parent))) => panic!(
556 "View {} was laid out without a parent when it was constructed with parent {}",
557 print_error(view_id),
558 print_error(*app_parent)
559 ),
560 (Some(layout_parent), Some(ParentId::Root)) => panic!(
561 "View {} was laid out with parent {} when it was constructed as a window root",
562 print_error(view_id),
563 print_error(*layout_parent),
564 ),
565 (_, None) => panic!(
566 "View {} did not have a registered parent in the app context",
567 print_error(view_id),
568 ),
569 _ => {}
570 }
571
572 self.view_stack.push(view_id);
573 let mut rendered_view = self.rendered_views.remove(&view_id).unwrap();
574 let size = rendered_view.layout(constraint, self);
575 self.rendered_views.insert(view_id, rendered_view);
576 self.view_stack.pop();
577 size
578 }
579
580 pub fn render<F, V, T>(&mut self, handle: &ViewHandle<V>, f: F) -> T
581 where
582 F: FnOnce(&mut V, &mut RenderContext<V>) -> T,
583 V: View,
584 {
585 handle.update(self.app, |view, cx| {
586 let mut render_cx = RenderContext {
587 app: cx,
588 window_id: handle.window_id(),
589 view_id: handle.id(),
590 view_type: PhantomData,
591 titlebar_height: self.titlebar_height,
592 hovered_region_ids: self.hovered_region_ids.clone(),
593 clicked_region_ids: self.clicked_region_ids.clone(),
594 refreshing: self.refreshing,
595 };
596 f(view, &mut render_cx)
597 })
598 }
599}
600
601impl<'a> Deref for LayoutContext<'a> {
602 type Target = MutableAppContext;
603
604 fn deref(&self) -> &Self::Target {
605 self.app
606 }
607}
608
609impl<'a> DerefMut for LayoutContext<'a> {
610 fn deref_mut(&mut self) -> &mut Self::Target {
611 self.app
612 }
613}
614
615impl<'a> ReadView for LayoutContext<'a> {
616 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
617 self.app.read_view(handle)
618 }
619}
620
621impl<'a> ReadModel for LayoutContext<'a> {
622 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
623 self.app.read_model(handle)
624 }
625}
626
627impl<'a> UpgradeModelHandle for LayoutContext<'a> {
628 fn upgrade_model_handle<T: Entity>(
629 &self,
630 handle: &WeakModelHandle<T>,
631 ) -> Option<ModelHandle<T>> {
632 self.app.upgrade_model_handle(handle)
633 }
634
635 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
636 self.app.model_handle_is_upgradable(handle)
637 }
638
639 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
640 self.app.upgrade_any_model_handle(handle)
641 }
642}
643
644impl<'a> UpgradeViewHandle for LayoutContext<'a> {
645 fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
646 self.app.upgrade_view_handle(handle)
647 }
648
649 fn upgrade_any_view_handle(&self, handle: &crate::AnyWeakViewHandle) -> Option<AnyViewHandle> {
650 self.app.upgrade_any_view_handle(handle)
651 }
652}
653
654pub struct PaintContext<'a> {
655 rendered_views: &'a mut HashMap<usize, ElementBox>,
656 view_stack: Vec<usize>,
657 pub window_size: Vector2F,
658 pub scene: &'a mut Scene,
659 pub font_cache: &'a FontCache,
660 pub text_layout_cache: &'a TextLayoutCache,
661 pub app: &'a AppContext,
662}
663
664impl<'a> PaintContext<'a> {
665 fn paint(&mut self, view_id: usize, origin: Vector2F, visible_bounds: RectF) {
666 if let Some(mut tree) = self.rendered_views.remove(&view_id) {
667 self.view_stack.push(view_id);
668 tree.paint(origin, visible_bounds, self);
669 self.rendered_views.insert(view_id, tree);
670 self.view_stack.pop();
671 }
672 }
673
674 #[inline]
675 pub fn paint_layer<F>(&mut self, clip_bounds: Option<RectF>, f: F)
676 where
677 F: FnOnce(&mut Self),
678 {
679 self.scene.push_layer(clip_bounds);
680 f(self);
681 self.scene.pop_layer();
682 }
683
684 pub fn current_view_id(&self) -> usize {
685 *self.view_stack.last().unwrap()
686 }
687}
688
689impl<'a> Deref for PaintContext<'a> {
690 type Target = AppContext;
691
692 fn deref(&self) -> &Self::Target {
693 self.app
694 }
695}
696
697pub struct EventContext<'a> {
698 rendered_views: &'a mut HashMap<usize, ElementBox>,
699 pub font_cache: &'a FontCache,
700 pub text_layout_cache: &'a TextLayoutCache,
701 pub app: &'a mut MutableAppContext,
702 pub window_id: usize,
703 pub notify_count: usize,
704 view_stack: Vec<usize>,
705 handled: bool,
706 invalidated_views: &'a mut HashSet<usize>,
707}
708
709impl<'a> EventContext<'a> {
710 fn dispatch_event(&mut self, view_id: usize, event: &Event) -> bool {
711 if let Some(mut element) = self.rendered_views.remove(&view_id) {
712 let result =
713 self.with_current_view(view_id, |this| element.dispatch_event(event, this));
714 self.rendered_views.insert(view_id, element);
715 result
716 } else {
717 false
718 }
719 }
720
721 fn with_current_view<F, T>(&mut self, view_id: usize, f: F) -> T
722 where
723 F: FnOnce(&mut Self) -> T,
724 {
725 self.view_stack.push(view_id);
726 let result = f(self);
727 self.view_stack.pop();
728 result
729 }
730
731 pub fn window_id(&self) -> usize {
732 self.window_id
733 }
734
735 pub fn view_id(&self) -> Option<usize> {
736 self.view_stack.last().copied()
737 }
738
739 pub fn is_parent_view_focused(&self) -> bool {
740 if let Some(parent_view_id) = self.view_stack.last() {
741 self.app.focused_view_id(self.window_id) == Some(*parent_view_id)
742 } else {
743 false
744 }
745 }
746
747 pub fn focus_parent_view(&mut self) {
748 if let Some(parent_view_id) = self.view_stack.last() {
749 self.app.focus(self.window_id, Some(*parent_view_id))
750 }
751 }
752
753 pub fn dispatch_any_action(&mut self, action: Box<dyn Action>) {
754 self.app
755 .dispatch_any_action_at(self.window_id, *self.view_stack.last().unwrap(), action)
756 }
757
758 pub fn dispatch_action<A: Action>(&mut self, action: A) {
759 self.dispatch_any_action(Box::new(action));
760 }
761
762 pub fn notify(&mut self) {
763 self.notify_count += 1;
764 if let Some(view_id) = self.view_stack.last() {
765 self.invalidated_views.insert(*view_id);
766 }
767 }
768
769 pub fn notify_count(&self) -> usize {
770 self.notify_count
771 }
772
773 pub fn propogate_event(&mut self) {
774 self.handled = false;
775 }
776}
777
778impl<'a> Deref for EventContext<'a> {
779 type Target = MutableAppContext;
780
781 fn deref(&self) -> &Self::Target {
782 self.app
783 }
784}
785
786impl<'a> DerefMut for EventContext<'a> {
787 fn deref_mut(&mut self) -> &mut Self::Target {
788 self.app
789 }
790}
791
792pub struct MeasurementContext<'a> {
793 app: &'a AppContext,
794 rendered_views: &'a HashMap<usize, ElementBox>,
795 pub window_id: usize,
796}
797
798impl<'a> Deref for MeasurementContext<'a> {
799 type Target = AppContext;
800
801 fn deref(&self) -> &Self::Target {
802 self.app
803 }
804}
805
806impl<'a> MeasurementContext<'a> {
807 fn rect_for_text_range(&self, view_id: usize, range_utf16: Range<usize>) -> Option<RectF> {
808 let element = self.rendered_views.get(&view_id)?;
809 element.rect_for_text_range(range_utf16, self)
810 }
811}
812
813pub struct DebugContext<'a> {
814 rendered_views: &'a HashMap<usize, ElementBox>,
815 pub font_cache: &'a FontCache,
816 pub app: &'a AppContext,
817}
818
819#[derive(Clone, Copy, Debug, Eq, PartialEq)]
820pub enum Axis {
821 Horizontal,
822 Vertical,
823}
824
825impl Axis {
826 pub fn invert(self) -> Self {
827 match self {
828 Self::Horizontal => Self::Vertical,
829 Self::Vertical => Self::Horizontal,
830 }
831 }
832}
833
834impl ToJson for Axis {
835 fn to_json(&self) -> serde_json::Value {
836 match self {
837 Axis::Horizontal => json!("horizontal"),
838 Axis::Vertical => json!("vertical"),
839 }
840 }
841}
842
843pub trait Vector2FExt {
844 fn along(self, axis: Axis) -> f32;
845}
846
847impl Vector2FExt for Vector2F {
848 fn along(self, axis: Axis) -> f32 {
849 match axis {
850 Axis::Horizontal => self.x(),
851 Axis::Vertical => self.y(),
852 }
853 }
854}
855
856#[derive(Copy, Clone, Debug)]
857pub struct SizeConstraint {
858 pub min: Vector2F,
859 pub max: Vector2F,
860}
861
862impl SizeConstraint {
863 pub fn new(min: Vector2F, max: Vector2F) -> Self {
864 Self { min, max }
865 }
866
867 pub fn strict(size: Vector2F) -> Self {
868 Self {
869 min: size,
870 max: size,
871 }
872 }
873
874 pub fn strict_along(axis: Axis, max: f32) -> Self {
875 match axis {
876 Axis::Horizontal => Self {
877 min: vec2f(max, 0.0),
878 max: vec2f(max, f32::INFINITY),
879 },
880 Axis::Vertical => Self {
881 min: vec2f(0.0, max),
882 max: vec2f(f32::INFINITY, max),
883 },
884 }
885 }
886
887 pub fn max_along(&self, axis: Axis) -> f32 {
888 match axis {
889 Axis::Horizontal => self.max.x(),
890 Axis::Vertical => self.max.y(),
891 }
892 }
893
894 pub fn min_along(&self, axis: Axis) -> f32 {
895 match axis {
896 Axis::Horizontal => self.min.x(),
897 Axis::Vertical => self.min.y(),
898 }
899 }
900
901 pub fn constrain(&self, size: Vector2F) -> Vector2F {
902 vec2f(
903 size.x().min(self.max.x()).max(self.min.x()),
904 size.y().min(self.max.y()).max(self.min.y()),
905 )
906 }
907}
908
909impl Default for SizeConstraint {
910 fn default() -> Self {
911 SizeConstraint {
912 min: Vector2F::zero(),
913 max: Vector2F::splat(f32::INFINITY),
914 }
915 }
916}
917
918impl ToJson for SizeConstraint {
919 fn to_json(&self) -> serde_json::Value {
920 json!({
921 "min": self.min.to_json(),
922 "max": self.max.to_json(),
923 })
924 }
925}
926
927pub struct ChildView {
928 view: AnyViewHandle,
929}
930
931impl ChildView {
932 pub fn new(view: impl Into<AnyViewHandle>) -> Self {
933 Self { view: view.into() }
934 }
935}
936
937impl Element for ChildView {
938 type LayoutState = ();
939 type PaintState = ();
940
941 fn layout(
942 &mut self,
943 constraint: SizeConstraint,
944 cx: &mut LayoutContext,
945 ) -> (Vector2F, Self::LayoutState) {
946 let size = cx.layout(self.view.id(), constraint);
947 (size, ())
948 }
949
950 fn paint(
951 &mut self,
952 bounds: RectF,
953 visible_bounds: RectF,
954 _: &mut Self::LayoutState,
955 cx: &mut PaintContext,
956 ) -> Self::PaintState {
957 cx.paint(self.view.id(), bounds.origin(), visible_bounds);
958 }
959
960 fn dispatch_event(
961 &mut self,
962 event: &Event,
963 _: RectF,
964 _: RectF,
965 _: &mut Self::LayoutState,
966 _: &mut Self::PaintState,
967 cx: &mut EventContext,
968 ) -> bool {
969 cx.dispatch_event(self.view.id(), event)
970 }
971
972 fn rect_for_text_range(
973 &self,
974 range_utf16: Range<usize>,
975 _: RectF,
976 _: RectF,
977 _: &Self::LayoutState,
978 _: &Self::PaintState,
979 cx: &MeasurementContext,
980 ) -> Option<RectF> {
981 cx.rect_for_text_range(self.view.id(), range_utf16)
982 }
983
984 fn debug(
985 &self,
986 bounds: RectF,
987 _: &Self::LayoutState,
988 _: &Self::PaintState,
989 cx: &DebugContext,
990 ) -> serde_json::Value {
991 json!({
992 "type": "ChildView",
993 "view_id": self.view.id(),
994 "bounds": bounds.to_json(),
995 "view": self.view.debug_json(cx.app),
996 "child": if let Some(view) = cx.rendered_views.get(&self.view.id()) {
997 view.debug(cx)
998 } else {
999 json!(null)
1000 }
1001 })
1002 }
1003}