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,
10 text_layout::TextLayoutCache,
11 Action, AnyModelHandle, AnyViewHandle, AnyWeakModelHandle, AssetCache, ElementBox, Entity,
12 FontSystem, ModelHandle, MouseRegion, MouseRegionId, ReadModel, ReadView, RenderContext,
13 RenderParams, Scene, UpgradeModelHandle, UpgradeViewHandle, View, ViewHandle, WeakModelHandle,
14 WeakViewHandle,
15};
16use pathfinder_geometry::vector::{vec2f, Vector2F};
17use serde_json::json;
18use smallvec::SmallVec;
19use std::{
20 collections::{HashMap, HashSet},
21 marker::PhantomData,
22 ops::{Deref, DerefMut},
23 sync::Arc,
24};
25
26pub struct Presenter {
27 window_id: usize,
28 pub(crate) rendered_views: HashMap<usize, ElementBox>,
29 parents: HashMap<usize, usize>,
30 cursor_regions: Vec<CursorRegion>,
31 mouse_regions: Vec<(MouseRegion, usize)>,
32 font_cache: Arc<FontCache>,
33 text_layout_cache: TextLayoutCache,
34 asset_cache: Arc<AssetCache>,
35 last_mouse_moved_event: Option<Event>,
36 hovered_region_ids: HashSet<MouseRegionId>,
37 clicked_region: Option<MouseRegion>,
38 right_clicked_region: Option<MouseRegion>,
39 prev_drag_position: Option<Vector2F>,
40 titlebar_height: f32,
41}
42
43impl Presenter {
44 pub fn new(
45 window_id: usize,
46 titlebar_height: f32,
47 font_cache: Arc<FontCache>,
48 text_layout_cache: TextLayoutCache,
49 asset_cache: Arc<AssetCache>,
50 cx: &mut MutableAppContext,
51 ) -> Self {
52 Self {
53 window_id,
54 rendered_views: cx.render_views(window_id, titlebar_height),
55 parents: HashMap::new(),
56 cursor_regions: Default::default(),
57 mouse_regions: Default::default(),
58 font_cache,
59 text_layout_cache,
60 asset_cache,
61 last_mouse_moved_event: None,
62 hovered_region_ids: Default::default(),
63 clicked_region: None,
64 right_clicked_region: None,
65 prev_drag_position: None,
66 titlebar_height,
67 }
68 }
69
70 pub fn dispatch_path(&self, app: &AppContext) -> Vec<usize> {
71 let mut path = Vec::new();
72 if let Some(view_id) = app.focused_view_id(self.window_id) {
73 self.compute_dispatch_path_from(view_id, &mut path)
74 }
75 path
76 }
77
78 pub(crate) fn compute_dispatch_path_from(&self, mut view_id: usize, path: &mut Vec<usize>) {
79 path.push(view_id);
80 while let Some(parent_id) = self.parents.get(&view_id).copied() {
81 path.push(parent_id);
82 view_id = parent_id;
83 }
84 path.reverse();
85 }
86
87 pub fn invalidate(
88 &mut self,
89 invalidation: &mut WindowInvalidation,
90 cx: &mut MutableAppContext,
91 ) {
92 cx.start_frame();
93 for view_id in &invalidation.removed {
94 invalidation.updated.remove(&view_id);
95 self.rendered_views.remove(&view_id);
96 self.parents.remove(&view_id);
97 }
98 for view_id in &invalidation.updated {
99 self.rendered_views.insert(
100 *view_id,
101 cx.render_view(RenderParams {
102 window_id: self.window_id,
103 view_id: *view_id,
104 titlebar_height: self.titlebar_height,
105 hovered_region_ids: self.hovered_region_ids.clone(),
106 clicked_region_id: self.clicked_region.as_ref().and_then(MouseRegion::id),
107 right_clicked_region_id: self
108 .right_clicked_region
109 .as_ref()
110 .and_then(MouseRegion::id),
111 refreshing: false,
112 })
113 .unwrap(),
114 );
115 }
116 }
117
118 pub fn refresh(&mut self, invalidation: &mut WindowInvalidation, cx: &mut MutableAppContext) {
119 self.invalidate(invalidation, cx);
120 for (view_id, view) in &mut self.rendered_views {
121 if !invalidation.updated.contains(view_id) {
122 *view = cx
123 .render_view(RenderParams {
124 window_id: self.window_id,
125 view_id: *view_id,
126 titlebar_height: self.titlebar_height,
127 hovered_region_ids: self.hovered_region_ids.clone(),
128 clicked_region_id: self.clicked_region.as_ref().and_then(MouseRegion::id),
129 right_clicked_region_id: self
130 .right_clicked_region
131 .as_ref()
132 .and_then(MouseRegion::id),
133 refreshing: true,
134 })
135 .unwrap();
136 }
137 }
138 }
139
140 pub fn build_scene(
141 &mut self,
142 window_size: Vector2F,
143 scale_factor: f32,
144 refreshing: bool,
145 cx: &mut MutableAppContext,
146 ) -> Scene {
147 let mut scene = Scene::new(scale_factor);
148
149 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
150 self.layout(window_size, refreshing, cx);
151 let mut paint_cx = self.build_paint_context(&mut scene, window_size, cx);
152 paint_cx.paint(
153 root_view_id,
154 Vector2F::zero(),
155 RectF::new(Vector2F::zero(), window_size),
156 );
157 self.text_layout_cache.finish_frame();
158 self.cursor_regions = scene.cursor_regions();
159 self.mouse_regions = scene.mouse_regions();
160
161 if cx.window_is_active(self.window_id) {
162 if let Some(event) = self.last_mouse_moved_event.clone() {
163 let mut invalidated_views = Vec::new();
164 self.handle_hover_events(&event, &mut invalidated_views, cx);
165
166 for view_id in invalidated_views {
167 cx.notify_view(self.window_id, view_id);
168 }
169 }
170 }
171 } else {
172 log::error!("could not find root_view_id for window {}", self.window_id);
173 }
174
175 scene
176 }
177
178 fn layout(&mut self, window_size: Vector2F, refreshing: bool, cx: &mut MutableAppContext) {
179 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
180 self.build_layout_context(window_size, refreshing, cx)
181 .layout(root_view_id, SizeConstraint::strict(window_size));
182 }
183 }
184
185 pub fn build_layout_context<'a>(
186 &'a mut self,
187 window_size: Vector2F,
188 refreshing: bool,
189 cx: &'a mut MutableAppContext,
190 ) -> LayoutContext<'a> {
191 LayoutContext {
192 window_id: self.window_id,
193 rendered_views: &mut self.rendered_views,
194 parents: &mut self.parents,
195 font_cache: &self.font_cache,
196 font_system: cx.platform().fonts(),
197 text_layout_cache: &self.text_layout_cache,
198 asset_cache: &self.asset_cache,
199 view_stack: Vec::new(),
200 refreshing,
201 hovered_region_ids: self.hovered_region_ids.clone(),
202 clicked_region_id: self.clicked_region.as_ref().and_then(MouseRegion::id),
203 right_clicked_region_id: self.right_clicked_region.as_ref().and_then(MouseRegion::id),
204 titlebar_height: self.titlebar_height,
205 window_size,
206 app: cx,
207 }
208 }
209
210 pub fn build_paint_context<'a>(
211 &'a mut self,
212 scene: &'a mut Scene,
213 window_size: Vector2F,
214 cx: &'a mut MutableAppContext,
215 ) -> PaintContext {
216 PaintContext {
217 scene,
218 window_size,
219 font_cache: &self.font_cache,
220 text_layout_cache: &self.text_layout_cache,
221 rendered_views: &mut self.rendered_views,
222 view_stack: Vec::new(),
223 app: cx,
224 }
225 }
226
227 pub fn dispatch_event(&mut self, event: Event, cx: &mut MutableAppContext) {
228 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
229 let mut invalidated_views = Vec::new();
230 let mut mouse_down_out_handlers = Vec::new();
231 let mut mouse_down_region = None;
232 let mut clicked_region = None;
233 let mut right_mouse_down_region = None;
234 let mut right_clicked_region = None;
235 let mut dragged_region = None;
236
237 match event {
238 Event::LeftMouseDown { position, .. } => {
239 let mut hit = false;
240 for (region, _) in self.mouse_regions.iter().rev() {
241 if region.bounds.contains_point(position) {
242 if !hit {
243 hit = true;
244 invalidated_views.push(region.view_id);
245 mouse_down_region = Some((region.clone(), position));
246 self.clicked_region = Some(region.clone());
247 self.prev_drag_position = Some(position);
248 }
249 } else if let Some(handler) = region.mouse_down_out.clone() {
250 mouse_down_out_handlers.push((handler, region.view_id, position));
251 }
252 }
253 }
254 Event::LeftMouseUp {
255 position,
256 click_count,
257 ..
258 } => {
259 self.prev_drag_position.take();
260 if let Some(region) = self.clicked_region.take() {
261 invalidated_views.push(region.view_id);
262 if region.bounds.contains_point(position) {
263 clicked_region = Some((region, position, click_count));
264 }
265 }
266 }
267 Event::RightMouseDown { position, .. } => {
268 let mut hit = false;
269 for (region, _) in self.mouse_regions.iter().rev() {
270 if region.bounds.contains_point(position) {
271 if !hit {
272 hit = true;
273 invalidated_views.push(region.view_id);
274 right_mouse_down_region = Some((region.clone(), position));
275 self.right_clicked_region = Some(region.clone());
276 }
277 } else if let Some(handler) = region.right_mouse_down_out.clone() {
278 mouse_down_out_handlers.push((handler, region.view_id, position));
279 }
280 }
281 }
282 Event::RightMouseUp {
283 position,
284 click_count,
285 ..
286 } => {
287 if let Some(region) = self.right_clicked_region.take() {
288 invalidated_views.push(region.view_id);
289 if region.bounds.contains_point(position) {
290 right_clicked_region = Some((region, position, click_count));
291 }
292 }
293 }
294 Event::MouseMoved { .. } => {
295 self.last_mouse_moved_event = Some(event.clone());
296 }
297 Event::LeftMouseDragged { position } => {
298 if let Some((clicked_region, prev_drag_position)) = self
299 .clicked_region
300 .as_ref()
301 .zip(self.prev_drag_position.as_mut())
302 {
303 dragged_region =
304 Some((clicked_region.clone(), position - *prev_drag_position));
305 *prev_drag_position = position;
306 }
307
308 self.last_mouse_moved_event = Some(Event::MouseMoved {
309 position,
310 left_mouse_down: true,
311 });
312 }
313 _ => {}
314 }
315
316 let (mut handled, mut event_cx) =
317 self.handle_hover_events(&event, &mut invalidated_views, cx);
318
319 for (handler, view_id, position) in mouse_down_out_handlers {
320 event_cx.with_current_view(view_id, |event_cx| handler(position, event_cx))
321 }
322
323 if let Some((mouse_down_region, position)) = mouse_down_region {
324 handled = true;
325 if let Some(mouse_down_callback) = mouse_down_region.mouse_down {
326 event_cx.with_current_view(mouse_down_region.view_id, |event_cx| {
327 mouse_down_callback(position, event_cx);
328 })
329 }
330 }
331
332 if let Some((clicked_region, position, click_count)) = clicked_region {
333 handled = true;
334 if let Some(click_callback) = clicked_region.click {
335 event_cx.with_current_view(clicked_region.view_id, |event_cx| {
336 click_callback(position, click_count, event_cx);
337 })
338 }
339 }
340
341 if let Some((right_mouse_down_region, position)) = right_mouse_down_region {
342 handled = true;
343 if let Some(right_mouse_down_callback) = right_mouse_down_region.right_mouse_down {
344 event_cx.with_current_view(right_mouse_down_region.view_id, |event_cx| {
345 right_mouse_down_callback(position, event_cx);
346 })
347 }
348 }
349
350 if let Some((right_clicked_region, position, click_count)) = right_clicked_region {
351 handled = true;
352 if let Some(right_click_callback) = right_clicked_region.right_click {
353 event_cx.with_current_view(right_clicked_region.view_id, |event_cx| {
354 right_click_callback(position, click_count, event_cx);
355 })
356 }
357 }
358
359 if let Some((dragged_region, delta)) = dragged_region {
360 handled = true;
361 if let Some(drag_callback) = dragged_region.drag {
362 event_cx.with_current_view(dragged_region.view_id, |event_cx| {
363 drag_callback(delta, event_cx);
364 })
365 }
366 }
367
368 if !handled {
369 event_cx.dispatch_event(root_view_id, &event);
370 }
371
372 invalidated_views.extend(event_cx.invalidated_views);
373 let dispatch_directives = event_cx.dispatched_actions;
374
375 for view_id in invalidated_views {
376 cx.notify_view(self.window_id, view_id);
377 }
378
379 let mut dispatch_path = Vec::new();
380 for directive in dispatch_directives {
381 dispatch_path.clear();
382 if let Some(view_id) = directive.dispatcher_view_id {
383 self.compute_dispatch_path_from(view_id, &mut dispatch_path);
384 }
385 cx.dispatch_action_any(self.window_id, &dispatch_path, directive.action.as_ref());
386 }
387 }
388 }
389
390 fn handle_hover_events<'a>(
391 &'a mut self,
392 event: &Event,
393 invalidated_views: &mut Vec<usize>,
394 cx: &'a mut MutableAppContext,
395 ) -> (bool, EventContext<'a>) {
396 let mut unhovered_regions = Vec::new();
397 let mut hovered_regions = Vec::new();
398
399 if let Event::MouseMoved {
400 position,
401 left_mouse_down,
402 } = event
403 {
404 if !left_mouse_down {
405 let mut style_to_assign = CursorStyle::Arrow;
406 for region in self.cursor_regions.iter().rev() {
407 if region.bounds.contains_point(*position) {
408 style_to_assign = region.style;
409 break;
410 }
411 }
412 cx.platform().set_cursor_style(style_to_assign);
413
414 let mut hover_depth = None;
415 for (region, depth) in self.mouse_regions.iter().rev() {
416 if region.bounds.contains_point(*position)
417 && hover_depth.map_or(true, |hover_depth| hover_depth == *depth)
418 {
419 hover_depth = Some(*depth);
420 if let Some(region_id) = region.id() {
421 if !self.hovered_region_ids.contains(®ion_id) {
422 invalidated_views.push(region.view_id);
423 hovered_regions.push((region.clone(), position));
424 self.hovered_region_ids.insert(region_id);
425 }
426 }
427 } else {
428 if let Some(region_id) = region.id() {
429 if self.hovered_region_ids.contains(®ion_id) {
430 invalidated_views.push(region.view_id);
431 unhovered_regions.push((region.clone(), position));
432 self.hovered_region_ids.remove(®ion_id);
433 }
434 }
435 }
436 }
437 }
438 }
439
440 let mut event_cx = self.build_event_context(cx);
441 let mut handled = false;
442
443 for (unhovered_region, position) in unhovered_regions {
444 handled = true;
445 if let Some(hover_callback) = unhovered_region.hover {
446 event_cx.with_current_view(unhovered_region.view_id, |event_cx| {
447 hover_callback(*position, false, event_cx);
448 })
449 }
450 }
451
452 for (hovered_region, position) in hovered_regions {
453 handled = true;
454 if let Some(hover_callback) = hovered_region.hover {
455 event_cx.with_current_view(hovered_region.view_id, |event_cx| {
456 hover_callback(*position, true, event_cx);
457 })
458 }
459 }
460
461 (handled, event_cx)
462 }
463
464 pub fn build_event_context<'a>(
465 &'a mut self,
466 cx: &'a mut MutableAppContext,
467 ) -> EventContext<'a> {
468 EventContext {
469 rendered_views: &mut self.rendered_views,
470 dispatched_actions: Default::default(),
471 font_cache: &self.font_cache,
472 text_layout_cache: &self.text_layout_cache,
473 view_stack: Default::default(),
474 invalidated_views: Default::default(),
475 notify_count: 0,
476 window_id: self.window_id,
477 app: cx,
478 }
479 }
480
481 pub fn debug_elements(&self, cx: &AppContext) -> Option<json::Value> {
482 let view = cx.root_view(self.window_id)?;
483 Some(json!({
484 "root_view": view.debug_json(cx),
485 "root_element": self.rendered_views.get(&view.id())
486 .map(|root_element| {
487 root_element.debug(&DebugContext {
488 rendered_views: &self.rendered_views,
489 font_cache: &self.font_cache,
490 app: cx,
491 })
492 })
493 }))
494 }
495}
496
497pub struct DispatchDirective {
498 pub dispatcher_view_id: Option<usize>,
499 pub action: Box<dyn Action>,
500}
501
502pub struct LayoutContext<'a> {
503 window_id: usize,
504 rendered_views: &'a mut HashMap<usize, ElementBox>,
505 parents: &'a mut HashMap<usize, usize>,
506 view_stack: Vec<usize>,
507 pub font_cache: &'a Arc<FontCache>,
508 pub font_system: Arc<dyn FontSystem>,
509 pub text_layout_cache: &'a TextLayoutCache,
510 pub asset_cache: &'a AssetCache,
511 pub app: &'a mut MutableAppContext,
512 pub refreshing: bool,
513 pub window_size: Vector2F,
514 titlebar_height: f32,
515 hovered_region_ids: HashSet<MouseRegionId>,
516 clicked_region_id: Option<MouseRegionId>,
517 right_clicked_region_id: Option<MouseRegionId>,
518}
519
520impl<'a> LayoutContext<'a> {
521 pub(crate) fn keystrokes_for_action(
522 &self,
523 action: &dyn Action,
524 ) -> Option<SmallVec<[Keystroke; 2]>> {
525 self.app
526 .keystrokes_for_action(self.window_id, &self.view_stack, action)
527 }
528
529 fn layout(&mut self, view_id: usize, constraint: SizeConstraint) -> Vector2F {
530 if let Some(parent_id) = self.view_stack.last() {
531 self.parents.insert(view_id, *parent_id);
532 }
533 self.view_stack.push(view_id);
534 let mut rendered_view = self.rendered_views.remove(&view_id).unwrap();
535 let size = rendered_view.layout(constraint, self);
536 self.rendered_views.insert(view_id, rendered_view);
537 self.view_stack.pop();
538 size
539 }
540
541 pub fn render<F, V, T>(&mut self, handle: &ViewHandle<V>, f: F) -> T
542 where
543 F: FnOnce(&mut V, &mut RenderContext<V>) -> T,
544 V: View,
545 {
546 handle.update(self.app, |view, cx| {
547 let mut render_cx = RenderContext {
548 app: cx,
549 window_id: handle.window_id(),
550 view_id: handle.id(),
551 view_type: PhantomData,
552 titlebar_height: self.titlebar_height,
553 hovered_region_ids: self.hovered_region_ids.clone(),
554 clicked_region_id: self.clicked_region_id,
555 right_clicked_region_id: self.right_clicked_region_id,
556 refreshing: self.refreshing,
557 };
558 f(view, &mut render_cx)
559 })
560 }
561}
562
563impl<'a> Deref for LayoutContext<'a> {
564 type Target = MutableAppContext;
565
566 fn deref(&self) -> &Self::Target {
567 self.app
568 }
569}
570
571impl<'a> DerefMut for LayoutContext<'a> {
572 fn deref_mut(&mut self) -> &mut Self::Target {
573 self.app
574 }
575}
576
577impl<'a> ReadView for LayoutContext<'a> {
578 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
579 self.app.read_view(handle)
580 }
581}
582
583impl<'a> ReadModel for LayoutContext<'a> {
584 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
585 self.app.read_model(handle)
586 }
587}
588
589impl<'a> UpgradeModelHandle for LayoutContext<'a> {
590 fn upgrade_model_handle<T: Entity>(
591 &self,
592 handle: &WeakModelHandle<T>,
593 ) -> Option<ModelHandle<T>> {
594 self.app.upgrade_model_handle(handle)
595 }
596
597 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
598 self.app.model_handle_is_upgradable(handle)
599 }
600
601 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
602 self.app.upgrade_any_model_handle(handle)
603 }
604}
605
606impl<'a> UpgradeViewHandle for LayoutContext<'a> {
607 fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
608 self.app.upgrade_view_handle(handle)
609 }
610
611 fn upgrade_any_view_handle(&self, handle: &crate::AnyWeakViewHandle) -> Option<AnyViewHandle> {
612 self.app.upgrade_any_view_handle(handle)
613 }
614}
615
616pub struct PaintContext<'a> {
617 rendered_views: &'a mut HashMap<usize, ElementBox>,
618 view_stack: Vec<usize>,
619 pub window_size: Vector2F,
620 pub scene: &'a mut Scene,
621 pub font_cache: &'a FontCache,
622 pub text_layout_cache: &'a TextLayoutCache,
623 pub app: &'a AppContext,
624}
625
626impl<'a> PaintContext<'a> {
627 fn paint(&mut self, view_id: usize, origin: Vector2F, visible_bounds: RectF) {
628 if let Some(mut tree) = self.rendered_views.remove(&view_id) {
629 self.view_stack.push(view_id);
630 tree.paint(origin, visible_bounds, self);
631 self.rendered_views.insert(view_id, tree);
632 self.view_stack.pop();
633 }
634 }
635
636 pub fn current_view_id(&self) -> usize {
637 *self.view_stack.last().unwrap()
638 }
639}
640
641impl<'a> Deref for PaintContext<'a> {
642 type Target = AppContext;
643
644 fn deref(&self) -> &Self::Target {
645 self.app
646 }
647}
648
649pub struct EventContext<'a> {
650 rendered_views: &'a mut HashMap<usize, ElementBox>,
651 dispatched_actions: Vec<DispatchDirective>,
652 pub font_cache: &'a FontCache,
653 pub text_layout_cache: &'a TextLayoutCache,
654 pub app: &'a mut MutableAppContext,
655 pub window_id: usize,
656 pub notify_count: usize,
657 view_stack: Vec<usize>,
658 invalidated_views: HashSet<usize>,
659}
660
661impl<'a> EventContext<'a> {
662 fn dispatch_event(&mut self, view_id: usize, event: &Event) -> bool {
663 if let Some(mut element) = self.rendered_views.remove(&view_id) {
664 let result =
665 self.with_current_view(view_id, |this| element.dispatch_event(event, this));
666 self.rendered_views.insert(view_id, element);
667 result
668 } else {
669 false
670 }
671 }
672
673 fn with_current_view<F, T>(&mut self, view_id: usize, f: F) -> T
674 where
675 F: FnOnce(&mut Self) -> T,
676 {
677 self.view_stack.push(view_id);
678 let result = f(self);
679 self.view_stack.pop();
680 result
681 }
682
683 pub fn window_id(&self) -> usize {
684 self.window_id
685 }
686
687 pub fn view_id(&self) -> Option<usize> {
688 self.view_stack.last().copied()
689 }
690
691 pub fn dispatch_any_action(&mut self, action: Box<dyn Action>) {
692 self.dispatched_actions.push(DispatchDirective {
693 dispatcher_view_id: self.view_stack.last().copied(),
694 action,
695 });
696 }
697
698 pub fn dispatch_action<A: Action>(&mut self, action: A) {
699 self.dispatch_any_action(Box::new(action));
700 }
701
702 pub fn notify(&mut self) {
703 self.notify_count += 1;
704 if let Some(view_id) = self.view_stack.last() {
705 self.invalidated_views.insert(*view_id);
706 }
707 }
708
709 pub fn notify_count(&self) -> usize {
710 self.notify_count
711 }
712}
713
714impl<'a> Deref for EventContext<'a> {
715 type Target = MutableAppContext;
716
717 fn deref(&self) -> &Self::Target {
718 self.app
719 }
720}
721
722impl<'a> DerefMut for EventContext<'a> {
723 fn deref_mut(&mut self) -> &mut Self::Target {
724 self.app
725 }
726}
727
728pub struct DebugContext<'a> {
729 rendered_views: &'a HashMap<usize, ElementBox>,
730 pub font_cache: &'a FontCache,
731 pub app: &'a AppContext,
732}
733
734#[derive(Clone, Copy, Debug, Eq, PartialEq)]
735pub enum Axis {
736 Horizontal,
737 Vertical,
738}
739
740impl Axis {
741 pub fn invert(self) -> Self {
742 match self {
743 Self::Horizontal => Self::Vertical,
744 Self::Vertical => Self::Horizontal,
745 }
746 }
747}
748
749impl ToJson for Axis {
750 fn to_json(&self) -> serde_json::Value {
751 match self {
752 Axis::Horizontal => json!("horizontal"),
753 Axis::Vertical => json!("vertical"),
754 }
755 }
756}
757
758pub trait Vector2FExt {
759 fn along(self, axis: Axis) -> f32;
760}
761
762impl Vector2FExt for Vector2F {
763 fn along(self, axis: Axis) -> f32 {
764 match axis {
765 Axis::Horizontal => self.x(),
766 Axis::Vertical => self.y(),
767 }
768 }
769}
770
771#[derive(Copy, Clone, Debug)]
772pub struct SizeConstraint {
773 pub min: Vector2F,
774 pub max: Vector2F,
775}
776
777impl SizeConstraint {
778 pub fn new(min: Vector2F, max: Vector2F) -> Self {
779 Self { min, max }
780 }
781
782 pub fn strict(size: Vector2F) -> Self {
783 Self {
784 min: size,
785 max: size,
786 }
787 }
788
789 pub fn strict_along(axis: Axis, max: f32) -> Self {
790 match axis {
791 Axis::Horizontal => Self {
792 min: vec2f(max, 0.0),
793 max: vec2f(max, f32::INFINITY),
794 },
795 Axis::Vertical => Self {
796 min: vec2f(0.0, max),
797 max: vec2f(f32::INFINITY, max),
798 },
799 }
800 }
801
802 pub fn max_along(&self, axis: Axis) -> f32 {
803 match axis {
804 Axis::Horizontal => self.max.x(),
805 Axis::Vertical => self.max.y(),
806 }
807 }
808
809 pub fn min_along(&self, axis: Axis) -> f32 {
810 match axis {
811 Axis::Horizontal => self.min.x(),
812 Axis::Vertical => self.min.y(),
813 }
814 }
815
816 pub fn constrain(&self, size: Vector2F) -> Vector2F {
817 vec2f(
818 size.x().min(self.max.x()).max(self.min.x()),
819 size.y().min(self.max.y()).max(self.min.y()),
820 )
821 }
822}
823
824impl Default for SizeConstraint {
825 fn default() -> Self {
826 SizeConstraint {
827 min: Vector2F::zero(),
828 max: Vector2F::splat(f32::INFINITY),
829 }
830 }
831}
832
833impl ToJson for SizeConstraint {
834 fn to_json(&self) -> serde_json::Value {
835 json!({
836 "min": self.min.to_json(),
837 "max": self.max.to_json(),
838 })
839 }
840}
841
842pub struct ChildView {
843 view: AnyViewHandle,
844}
845
846impl ChildView {
847 pub fn new(view: impl Into<AnyViewHandle>) -> Self {
848 Self { view: view.into() }
849 }
850}
851
852impl Element for ChildView {
853 type LayoutState = ();
854 type PaintState = ();
855
856 fn layout(
857 &mut self,
858 constraint: SizeConstraint,
859 cx: &mut LayoutContext,
860 ) -> (Vector2F, Self::LayoutState) {
861 let size = cx.layout(self.view.id(), constraint);
862 (size, ())
863 }
864
865 fn paint(
866 &mut self,
867 bounds: RectF,
868 visible_bounds: RectF,
869 _: &mut Self::LayoutState,
870 cx: &mut PaintContext,
871 ) -> Self::PaintState {
872 cx.paint(self.view.id(), bounds.origin(), visible_bounds);
873 }
874
875 fn dispatch_event(
876 &mut self,
877 event: &Event,
878 _: RectF,
879 _: RectF,
880 _: &mut Self::LayoutState,
881 _: &mut Self::PaintState,
882 cx: &mut EventContext,
883 ) -> bool {
884 cx.dispatch_event(self.view.id(), event)
885 }
886
887 fn debug(
888 &self,
889 bounds: RectF,
890 _: &Self::LayoutState,
891 _: &Self::PaintState,
892 cx: &DebugContext,
893 ) -> serde_json::Value {
894 json!({
895 "type": "ChildView",
896 "view_id": self.view.id(),
897 "bounds": bounds.to_json(),
898 "view": self.view.debug_json(cx.app),
899 "child": if let Some(view) = cx.rendered_views.get(&self.view.id()) {
900 view.debug(cx)
901 } else {
902 json!(null)
903 }
904 })
905 }
906}