1use crate::{
2 app::{AppContext, MutableAppContext, WindowInvalidation},
3 elements::Element,
4 font_cache::FontCache,
5 geometry::rect::RectF,
6 json::{self, ToJson},
7 keymap_matcher::Keystroke,
8 platform::{CursorStyle, Event},
9 scene::{
10 CursorRegion, MouseClick, MouseDown, MouseDownOut, MouseDrag, MouseEvent, MouseHover,
11 MouseMove, MouseMoveOut, MouseScrollWheel, MouseUp, MouseUpOut, Scene,
12 },
13 text_layout::TextLayoutCache,
14 Action, AnyModelHandle, AnyViewHandle, AnyWeakModelHandle, AnyWeakViewHandle, Appearance,
15 AssetCache, ElementBox, Entity, FontSystem, ModelHandle, MouseButton, MouseMovedEvent,
16 MouseRegion, MouseRegionId, ParentId, ReadModel, ReadView, RenderContext, RenderParams,
17 SceneBuilder, UpgradeModelHandle, UpgradeViewHandle, View, ViewHandle, WeakModelHandle,
18 WeakViewHandle,
19};
20use anyhow::bail;
21use collections::{HashMap, HashSet};
22use pathfinder_geometry::vector::{vec2f, Vector2F};
23use serde_json::json;
24use smallvec::SmallVec;
25use sqlez::{
26 bindable::{Bind, Column},
27 statement::Statement,
28};
29use std::{
30 marker::PhantomData,
31 ops::{Deref, DerefMut, Range},
32 sync::Arc,
33};
34
35pub struct Presenter {
36 window_id: usize,
37 pub(crate) rendered_views: HashMap<usize, ElementBox>,
38 cursor_regions: Vec<CursorRegion>,
39 mouse_regions: Vec<(MouseRegion, usize)>,
40 font_cache: Arc<FontCache>,
41 text_layout_cache: TextLayoutCache,
42 asset_cache: Arc<AssetCache>,
43 last_mouse_moved_event: Option<Event>,
44 hovered_region_ids: HashSet<MouseRegionId>,
45 clicked_region_ids: HashSet<MouseRegionId>,
46 clicked_button: Option<MouseButton>,
47 mouse_position: Vector2F,
48 titlebar_height: f32,
49 appearance: Appearance,
50}
51
52impl Presenter {
53 pub fn new(
54 window_id: usize,
55 titlebar_height: f32,
56 appearance: Appearance,
57 font_cache: Arc<FontCache>,
58 text_layout_cache: TextLayoutCache,
59 asset_cache: Arc<AssetCache>,
60 cx: &mut MutableAppContext,
61 ) -> Self {
62 Self {
63 window_id,
64 rendered_views: cx.render_views(window_id, titlebar_height, appearance),
65 cursor_regions: Default::default(),
66 mouse_regions: Default::default(),
67 font_cache,
68 text_layout_cache,
69 asset_cache,
70 last_mouse_moved_event: None,
71 hovered_region_ids: Default::default(),
72 clicked_region_ids: Default::default(),
73 clicked_button: None,
74 mouse_position: vec2f(0., 0.),
75 titlebar_height,
76 appearance,
77 }
78 }
79
80 pub fn invalidate(
81 &mut self,
82 invalidation: &mut WindowInvalidation,
83 appearance: Appearance,
84 cx: &mut MutableAppContext,
85 ) {
86 cx.start_frame();
87 self.appearance = appearance;
88 for view_id in &invalidation.removed {
89 invalidation.updated.remove(view_id);
90 self.rendered_views.remove(view_id);
91 }
92 for view_id in &invalidation.updated {
93 self.rendered_views.insert(
94 *view_id,
95 cx.render_view(RenderParams {
96 window_id: self.window_id,
97 view_id: *view_id,
98 titlebar_height: self.titlebar_height,
99 hovered_region_ids: self.hovered_region_ids.clone(),
100 clicked_region_ids: self
101 .clicked_button
102 .map(|button| (self.clicked_region_ids.clone(), button)),
103 refreshing: false,
104 appearance,
105 })
106 .unwrap(),
107 );
108 }
109 }
110
111 pub fn refresh(
112 &mut self,
113 invalidation: &mut WindowInvalidation,
114 appearance: Appearance,
115 cx: &mut MutableAppContext,
116 ) {
117 self.invalidate(invalidation, appearance, cx);
118 for (view_id, view) in &mut self.rendered_views {
119 if !invalidation.updated.contains(view_id) {
120 *view = cx
121 .render_view(RenderParams {
122 window_id: self.window_id,
123 view_id: *view_id,
124 titlebar_height: self.titlebar_height,
125 hovered_region_ids: self.hovered_region_ids.clone(),
126 clicked_region_ids: self
127 .clicked_button
128 .map(|button| (self.clicked_region_ids.clone(), button)),
129 refreshing: true,
130 appearance,
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_builder = SceneBuilder::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_builder, 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 let scene = scene_builder.build();
156 self.cursor_regions = scene.cursor_regions();
157 self.mouse_regions = scene.mouse_regions();
158
159 // window.is_topmost for the mouse moved event's postion?
160 if cx.window_is_active(self.window_id) {
161 if let Some(event) = self.last_mouse_moved_event.clone() {
162 self.dispatch_event(event, true, cx);
163 }
164 }
165
166 scene
167 } else {
168 log::error!("could not find root_view_id for window {}", self.window_id);
169 scene_builder.build()
170 }
171 }
172
173 fn layout(&mut self, window_size: Vector2F, refreshing: bool, cx: &mut MutableAppContext) {
174 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
175 self.build_layout_context(window_size, refreshing, cx)
176 .layout(root_view_id, SizeConstraint::strict(window_size));
177 }
178 }
179
180 pub fn build_layout_context<'a>(
181 &'a mut self,
182 window_size: Vector2F,
183 refreshing: bool,
184 cx: &'a mut MutableAppContext,
185 ) -> LayoutContext<'a> {
186 LayoutContext {
187 window_id: self.window_id,
188 rendered_views: &mut self.rendered_views,
189 font_cache: &self.font_cache,
190 font_system: cx.platform().fonts(),
191 text_layout_cache: &self.text_layout_cache,
192 asset_cache: &self.asset_cache,
193 view_stack: Vec::new(),
194 refreshing,
195 hovered_region_ids: self.hovered_region_ids.clone(),
196 clicked_region_ids: self
197 .clicked_button
198 .map(|button| (self.clicked_region_ids.clone(), button)),
199 titlebar_height: self.titlebar_height,
200 appearance: self.appearance,
201 window_size,
202 app: cx,
203 }
204 }
205
206 pub fn build_paint_context<'a>(
207 &'a mut self,
208 scene: &'a mut SceneBuilder,
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(
235 &mut self,
236 event: Event,
237 event_reused: bool,
238 cx: &mut MutableAppContext,
239 ) -> bool {
240 let mut mouse_events = SmallVec::<[_; 2]>::new();
241 let mut notified_views: HashSet<usize> = Default::default();
242
243 // 1. Handle platform event. Keyboard events get dispatched immediately, while mouse events
244 // get mapped into the mouse-specific MouseEvent type.
245 // -> These are usually small: [Mouse Down] or [Mouse up, Click] or [Mouse Moved, Mouse Dragged?]
246 // -> Also updates mouse-related state
247 match &event {
248 Event::KeyDown(e) => return cx.dispatch_key_down(self.window_id, e),
249
250 Event::KeyUp(e) => return cx.dispatch_key_up(self.window_id, e),
251
252 Event::ModifiersChanged(e) => return cx.dispatch_modifiers_changed(self.window_id, e),
253
254 Event::MouseDown(e) => {
255 // Click events are weird because they can be fired after a drag event.
256 // MDN says that browsers handle this by starting from 'the most
257 // specific ancestor element that contained both [positions]'
258 // So we need to store the overlapping regions on mouse down.
259
260 // If there is already clicked_button stored, don't replace it.
261 if self.clicked_button.is_none() {
262 self.clicked_region_ids = self
263 .mouse_regions
264 .iter()
265 .filter_map(|(region, _)| {
266 if region.bounds.contains_point(e.position) {
267 Some(region.id())
268 } else {
269 None
270 }
271 })
272 .collect();
273
274 self.clicked_button = Some(e.button);
275 }
276
277 mouse_events.push(MouseEvent::Down(MouseDown {
278 region: Default::default(),
279 platform_event: e.clone(),
280 }));
281 mouse_events.push(MouseEvent::DownOut(MouseDownOut {
282 region: Default::default(),
283 platform_event: e.clone(),
284 }));
285 }
286
287 Event::MouseUp(e) => {
288 // NOTE: The order of event pushes is important! MouseUp events MUST be fired
289 // before click events, and so the MouseUp events need to be pushed before
290 // MouseClick events.
291 mouse_events.push(MouseEvent::Up(MouseUp {
292 region: Default::default(),
293 platform_event: e.clone(),
294 }));
295 mouse_events.push(MouseEvent::UpOut(MouseUpOut {
296 region: Default::default(),
297 platform_event: e.clone(),
298 }));
299 mouse_events.push(MouseEvent::Click(MouseClick {
300 region: Default::default(),
301 platform_event: e.clone(),
302 }));
303 }
304
305 Event::MouseMoved(
306 e @ MouseMovedEvent {
307 position,
308 pressed_button,
309 ..
310 },
311 ) => {
312 let mut style_to_assign = CursorStyle::Arrow;
313 for region in self.cursor_regions.iter().rev() {
314 if region.bounds.contains_point(*position) {
315 style_to_assign = region.style;
316 break;
317 }
318 }
319
320 if cx.is_topmost_window_for_position(self.window_id, *position) {
321 cx.platform().set_cursor_style(style_to_assign);
322 }
323
324 if !event_reused {
325 if pressed_button.is_some() {
326 mouse_events.push(MouseEvent::Drag(MouseDrag {
327 region: Default::default(),
328 prev_mouse_position: self.mouse_position,
329 platform_event: e.clone(),
330 }));
331 } else if let Some(clicked_button) = self.clicked_button {
332 // Mouse up event happened outside the current window. Simulate mouse up button event
333 let button_event = e.to_button_event(clicked_button);
334 mouse_events.push(MouseEvent::Up(MouseUp {
335 region: Default::default(),
336 platform_event: button_event.clone(),
337 }));
338 mouse_events.push(MouseEvent::UpOut(MouseUpOut {
339 region: Default::default(),
340 platform_event: button_event.clone(),
341 }));
342 mouse_events.push(MouseEvent::Click(MouseClick {
343 region: Default::default(),
344 platform_event: button_event.clone(),
345 }));
346 }
347
348 mouse_events.push(MouseEvent::Move(MouseMove {
349 region: Default::default(),
350 platform_event: e.clone(),
351 }));
352 }
353
354 mouse_events.push(MouseEvent::Hover(MouseHover {
355 region: Default::default(),
356 platform_event: e.clone(),
357 started: false,
358 }));
359 mouse_events.push(MouseEvent::MoveOut(MouseMoveOut {
360 region: Default::default(),
361 }));
362
363 self.last_mouse_moved_event = Some(event.clone());
364 }
365
366 Event::MouseExited(event) => {
367 // When the platform sends a MouseExited event, synthesize
368 // a MouseMoved event whose position is outside the window's
369 // bounds so that hover and cursor state can be updated.
370 return self.dispatch_event(
371 Event::MouseMoved(MouseMovedEvent {
372 position: event.position,
373 pressed_button: event.pressed_button,
374 modifiers: event.modifiers,
375 }),
376 event_reused,
377 cx,
378 );
379 }
380
381 Event::ScrollWheel(e) => mouse_events.push(MouseEvent::ScrollWheel(MouseScrollWheel {
382 region: Default::default(),
383 platform_event: e.clone(),
384 })),
385 }
386
387 if let Some(position) = event.position() {
388 self.mouse_position = position;
389 }
390
391 // 2. Dispatch mouse events on regions
392 let mut any_event_handled = false;
393 for mut mouse_event in mouse_events {
394 let mut valid_regions = Vec::new();
395
396 // GPUI elements are arranged by z_index but sibling elements can register overlapping
397 // mouse regions. As such, hover events are only fired on overlapping elements which
398 // are at the same z-index as the topmost element which overlaps with the mouse.
399 match &mouse_event {
400 MouseEvent::Hover(_) => {
401 let mut highest_z_index = None;
402 let mouse_position = self.mouse_position.clone();
403 for (region, z_index) in self.mouse_regions.iter().rev() {
404 // Allow mouse regions to appear transparent to hovers
405 if !region.hoverable {
406 continue;
407 }
408
409 let contains_mouse = region.bounds.contains_point(mouse_position);
410
411 if contains_mouse && highest_z_index.is_none() {
412 highest_z_index = Some(z_index);
413 }
414
415 // This unwrap relies on short circuiting boolean expressions
416 // The right side of the && is only executed when contains_mouse
417 // is true, and we know above that when contains_mouse is true
418 // highest_z_index is set.
419 if contains_mouse && z_index == highest_z_index.unwrap() {
420 //Ensure that hover entrance events aren't sent twice
421 if self.hovered_region_ids.insert(region.id()) {
422 valid_regions.push(region.clone());
423 if region.notify_on_hover {
424 notified_views.insert(region.id().view_id());
425 }
426 }
427 } else {
428 // Ensure that hover exit events aren't sent twice
429 if self.hovered_region_ids.remove(®ion.id()) {
430 valid_regions.push(region.clone());
431 if region.notify_on_hover {
432 notified_views.insert(region.id().view_id());
433 }
434 }
435 }
436 }
437 }
438
439 MouseEvent::Down(_) | MouseEvent::Up(_) => {
440 for (region, _) in self.mouse_regions.iter().rev() {
441 if region.bounds.contains_point(self.mouse_position) {
442 valid_regions.push(region.clone());
443 if region.notify_on_click {
444 notified_views.insert(region.id().view_id());
445 }
446 }
447 }
448 }
449
450 MouseEvent::Click(e) => {
451 // Only raise click events if the released button is the same as the one stored
452 if self
453 .clicked_button
454 .map(|clicked_button| clicked_button == e.button)
455 .unwrap_or(false)
456 {
457 // Clear clicked regions and clicked button
458 let clicked_region_ids =
459 std::mem::replace(&mut self.clicked_region_ids, Default::default());
460 self.clicked_button = None;
461
462 // Find regions which still overlap with the mouse since the last MouseDown happened
463 for (mouse_region, _) in self.mouse_regions.iter().rev() {
464 if clicked_region_ids.contains(&mouse_region.id()) {
465 if mouse_region.bounds.contains_point(self.mouse_position) {
466 valid_regions.push(mouse_region.clone());
467 }
468 }
469 }
470 }
471 }
472
473 MouseEvent::Drag(_) => {
474 for (mouse_region, _) in self.mouse_regions.iter().rev() {
475 if self.clicked_region_ids.contains(&mouse_region.id()) {
476 valid_regions.push(mouse_region.clone());
477 }
478 }
479 }
480
481 MouseEvent::MoveOut(_) | MouseEvent::UpOut(_) | MouseEvent::DownOut(_) => {
482 for (mouse_region, _) in self.mouse_regions.iter().rev() {
483 // NOT contains
484 if !mouse_region.bounds.contains_point(self.mouse_position) {
485 valid_regions.push(mouse_region.clone());
486 }
487 }
488 }
489
490 _ => {
491 for (mouse_region, _) in self.mouse_regions.iter().rev() {
492 // Contains
493 if mouse_region.bounds.contains_point(self.mouse_position) {
494 valid_regions.push(mouse_region.clone());
495 }
496 }
497 }
498 }
499
500 //3. Fire region events
501 let hovered_region_ids = self.hovered_region_ids.clone();
502 for valid_region in valid_regions.into_iter() {
503 let mut event_cx = self.build_event_context(&mut notified_views, cx);
504
505 mouse_event.set_region(valid_region.bounds);
506 if let MouseEvent::Hover(e) = &mut mouse_event {
507 e.started = hovered_region_ids.contains(&valid_region.id())
508 }
509 // Handle Down events if the MouseRegion has a Click or Drag handler. This makes the api more intuitive as you would
510 // not expect a MouseRegion to be transparent to Down events if it also has a Click handler.
511 // This behavior can be overridden by adding a Down handler that calls cx.propogate_event
512 if let MouseEvent::Down(e) = &mouse_event {
513 if valid_region
514 .handlers
515 .contains(MouseEvent::click_disc(), Some(e.button))
516 || valid_region
517 .handlers
518 .contains(MouseEvent::drag_disc(), Some(e.button))
519 {
520 event_cx.handled = true;
521 }
522 }
523
524 // `event_consumed` should only be true if there are any handlers for this event.
525 let mut event_consumed = event_cx.handled;
526 if let Some(callbacks) = valid_region.handlers.get(&mouse_event.handler_key()) {
527 event_consumed = true;
528 for callback in callbacks {
529 event_cx.handled = true;
530 event_cx.with_current_view(valid_region.id().view_id(), {
531 let region_event = mouse_event.clone();
532 |cx| callback(region_event, cx)
533 });
534 event_consumed &= event_cx.handled;
535 any_event_handled |= event_cx.handled;
536 }
537 }
538
539 any_event_handled |= event_cx.handled;
540
541 // For bubbling events, if the event was handled, don't continue dispatching.
542 // This only makes sense for local events which return false from is_capturable.
543 if event_consumed && mouse_event.is_capturable() {
544 break;
545 }
546 }
547 }
548
549 for view_id in notified_views {
550 cx.notify_view(self.window_id, view_id);
551 }
552
553 any_event_handled
554 }
555
556 pub fn build_event_context<'a>(
557 &'a mut self,
558 notified_views: &'a mut HashSet<usize>,
559 cx: &'a mut MutableAppContext,
560 ) -> EventContext<'a> {
561 EventContext {
562 font_cache: &self.font_cache,
563 text_layout_cache: &self.text_layout_cache,
564 view_stack: Default::default(),
565 notified_views,
566 notify_count: 0,
567 handled: false,
568 window_id: self.window_id,
569 app: cx,
570 }
571 }
572
573 pub fn debug_elements(&self, cx: &AppContext) -> Option<json::Value> {
574 let view = cx.root_view(self.window_id)?;
575 Some(json!({
576 "root_view": view.debug_json(cx),
577 "root_element": self.rendered_views.get(&view.id())
578 .map(|root_element| {
579 root_element.debug(&DebugContext {
580 rendered_views: &self.rendered_views,
581 font_cache: &self.font_cache,
582 app: cx,
583 })
584 })
585 }))
586 }
587}
588
589pub struct LayoutContext<'a> {
590 window_id: usize,
591 rendered_views: &'a mut HashMap<usize, ElementBox>,
592 view_stack: Vec<usize>,
593 pub font_cache: &'a Arc<FontCache>,
594 pub font_system: Arc<dyn FontSystem>,
595 pub text_layout_cache: &'a TextLayoutCache,
596 pub asset_cache: &'a AssetCache,
597 pub app: &'a mut MutableAppContext,
598 pub refreshing: bool,
599 pub window_size: Vector2F,
600 titlebar_height: f32,
601 appearance: Appearance,
602 hovered_region_ids: HashSet<MouseRegionId>,
603 clicked_region_ids: Option<(HashSet<MouseRegionId>, MouseButton)>,
604}
605
606impl<'a> LayoutContext<'a> {
607 pub(crate) fn keystrokes_for_action(
608 &mut self,
609 action: &dyn Action,
610 ) -> Option<SmallVec<[Keystroke; 2]>> {
611 self.app
612 .keystrokes_for_action(self.window_id, &self.view_stack, action)
613 }
614
615 fn layout(&mut self, view_id: usize, constraint: SizeConstraint) -> Vector2F {
616 let print_error = |view_id| {
617 format!(
618 "{} with id {}",
619 self.app.name_for_view(self.window_id, view_id).unwrap(),
620 view_id,
621 )
622 };
623 match (
624 self.view_stack.last(),
625 self.app.parents.get(&(self.window_id, view_id)),
626 ) {
627 (Some(layout_parent), Some(ParentId::View(app_parent))) => {
628 if layout_parent != app_parent {
629 panic!(
630 "View {} was laid out with parent {} when it was constructed with parent {}",
631 print_error(view_id),
632 print_error(*layout_parent),
633 print_error(*app_parent))
634 }
635 }
636 (None, Some(ParentId::View(app_parent))) => panic!(
637 "View {} was laid out without a parent when it was constructed with parent {}",
638 print_error(view_id),
639 print_error(*app_parent)
640 ),
641 (Some(layout_parent), Some(ParentId::Root)) => panic!(
642 "View {} was laid out with parent {} when it was constructed as a window root",
643 print_error(view_id),
644 print_error(*layout_parent),
645 ),
646 (_, None) => panic!(
647 "View {} did not have a registered parent in the app context",
648 print_error(view_id),
649 ),
650 _ => {}
651 }
652
653 self.view_stack.push(view_id);
654 let mut rendered_view = self.rendered_views.remove(&view_id).unwrap();
655 let size = rendered_view.layout(constraint, self);
656 self.rendered_views.insert(view_id, rendered_view);
657 self.view_stack.pop();
658 size
659 }
660
661 pub fn render<F, V, T>(&mut self, handle: &ViewHandle<V>, f: F) -> T
662 where
663 F: FnOnce(&mut V, &mut RenderContext<V>) -> T,
664 V: View,
665 {
666 handle.update(self.app, |view, cx| {
667 let mut render_cx = RenderContext {
668 app: cx,
669 window_id: handle.window_id(),
670 view_id: handle.id(),
671 view_type: PhantomData,
672 titlebar_height: self.titlebar_height,
673 hovered_region_ids: self.hovered_region_ids.clone(),
674 clicked_region_ids: self.clicked_region_ids.clone(),
675 refreshing: self.refreshing,
676 appearance: self.appearance,
677 };
678 f(view, &mut render_cx)
679 })
680 }
681}
682
683impl<'a> Deref for LayoutContext<'a> {
684 type Target = MutableAppContext;
685
686 fn deref(&self) -> &Self::Target {
687 self.app
688 }
689}
690
691impl<'a> DerefMut for LayoutContext<'a> {
692 fn deref_mut(&mut self) -> &mut Self::Target {
693 self.app
694 }
695}
696
697impl<'a> ReadView for LayoutContext<'a> {
698 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
699 self.app.read_view(handle)
700 }
701}
702
703impl<'a> ReadModel for LayoutContext<'a> {
704 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
705 self.app.read_model(handle)
706 }
707}
708
709impl<'a> UpgradeModelHandle for LayoutContext<'a> {
710 fn upgrade_model_handle<T: Entity>(
711 &self,
712 handle: &WeakModelHandle<T>,
713 ) -> Option<ModelHandle<T>> {
714 self.app.upgrade_model_handle(handle)
715 }
716
717 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
718 self.app.model_handle_is_upgradable(handle)
719 }
720
721 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
722 self.app.upgrade_any_model_handle(handle)
723 }
724}
725
726impl<'a> UpgradeViewHandle for LayoutContext<'a> {
727 fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
728 self.app.upgrade_view_handle(handle)
729 }
730
731 fn upgrade_any_view_handle(&self, handle: &crate::AnyWeakViewHandle) -> Option<AnyViewHandle> {
732 self.app.upgrade_any_view_handle(handle)
733 }
734}
735
736pub struct PaintContext<'a> {
737 rendered_views: &'a mut HashMap<usize, ElementBox>,
738 view_stack: Vec<usize>,
739 pub window_size: Vector2F,
740 pub scene: &'a mut SceneBuilder,
741 pub font_cache: &'a FontCache,
742 pub text_layout_cache: &'a TextLayoutCache,
743 pub app: &'a AppContext,
744}
745
746impl<'a> PaintContext<'a> {
747 fn paint(&mut self, view_id: usize, origin: Vector2F, visible_bounds: RectF) {
748 if let Some(mut tree) = self.rendered_views.remove(&view_id) {
749 self.view_stack.push(view_id);
750 tree.paint(origin, visible_bounds, self);
751 self.rendered_views.insert(view_id, tree);
752 self.view_stack.pop();
753 }
754 }
755
756 #[inline]
757 pub fn paint_stacking_context<F>(
758 &mut self,
759 clip_bounds: Option<RectF>,
760 z_index: Option<usize>,
761 f: F,
762 ) where
763 F: FnOnce(&mut Self),
764 {
765 self.scene.push_stacking_context(clip_bounds, z_index);
766 f(self);
767 self.scene.pop_stacking_context();
768 }
769
770 #[inline]
771 pub fn paint_layer<F>(&mut self, clip_bounds: Option<RectF>, f: F)
772 where
773 F: FnOnce(&mut Self),
774 {
775 self.scene.push_layer(clip_bounds);
776 f(self);
777 self.scene.pop_layer();
778 }
779
780 pub fn current_view_id(&self) -> usize {
781 *self.view_stack.last().unwrap()
782 }
783}
784
785impl<'a> Deref for PaintContext<'a> {
786 type Target = AppContext;
787
788 fn deref(&self) -> &Self::Target {
789 self.app
790 }
791}
792
793pub struct EventContext<'a> {
794 pub font_cache: &'a FontCache,
795 pub text_layout_cache: &'a TextLayoutCache,
796 pub app: &'a mut MutableAppContext,
797 pub window_id: usize,
798 pub notify_count: usize,
799 view_stack: Vec<usize>,
800 handled: bool,
801 notified_views: &'a mut HashSet<usize>,
802}
803
804impl<'a> EventContext<'a> {
805 fn with_current_view<F, T>(&mut self, view_id: usize, f: F) -> T
806 where
807 F: FnOnce(&mut Self) -> T,
808 {
809 self.view_stack.push(view_id);
810 let result = f(self);
811 self.view_stack.pop();
812 result
813 }
814
815 pub fn window_id(&self) -> usize {
816 self.window_id
817 }
818
819 pub fn view_id(&self) -> Option<usize> {
820 self.view_stack.last().copied()
821 }
822
823 pub fn is_parent_view_focused(&self) -> bool {
824 if let Some(parent_view_id) = self.view_stack.last() {
825 self.app.focused_view_id(self.window_id) == Some(*parent_view_id)
826 } else {
827 false
828 }
829 }
830
831 pub fn focus_parent_view(&mut self) {
832 if let Some(parent_view_id) = self.view_stack.last() {
833 self.app.focus(self.window_id, Some(*parent_view_id))
834 }
835 }
836
837 pub fn dispatch_any_action(&mut self, action: Box<dyn Action>) {
838 self.app
839 .dispatch_any_action_at(self.window_id, *self.view_stack.last().unwrap(), action)
840 }
841
842 pub fn dispatch_action<A: Action>(&mut self, action: A) {
843 self.dispatch_any_action(Box::new(action));
844 }
845
846 pub fn notify(&mut self) {
847 self.notify_count += 1;
848 if let Some(view_id) = self.view_stack.last() {
849 self.notified_views.insert(*view_id);
850 }
851 }
852
853 pub fn notify_count(&self) -> usize {
854 self.notify_count
855 }
856
857 pub fn propagate_event(&mut self) {
858 self.handled = false;
859 }
860}
861
862impl<'a> Deref for EventContext<'a> {
863 type Target = MutableAppContext;
864
865 fn deref(&self) -> &Self::Target {
866 self.app
867 }
868}
869
870impl<'a> DerefMut for EventContext<'a> {
871 fn deref_mut(&mut self) -> &mut Self::Target {
872 self.app
873 }
874}
875
876pub struct MeasurementContext<'a> {
877 app: &'a AppContext,
878 rendered_views: &'a HashMap<usize, ElementBox>,
879 pub window_id: usize,
880}
881
882impl<'a> Deref for MeasurementContext<'a> {
883 type Target = AppContext;
884
885 fn deref(&self) -> &Self::Target {
886 self.app
887 }
888}
889
890impl<'a> MeasurementContext<'a> {
891 fn rect_for_text_range(&self, view_id: usize, range_utf16: Range<usize>) -> Option<RectF> {
892 let element = self.rendered_views.get(&view_id)?;
893 element.rect_for_text_range(range_utf16, self)
894 }
895}
896
897pub struct DebugContext<'a> {
898 rendered_views: &'a HashMap<usize, ElementBox>,
899 pub font_cache: &'a FontCache,
900 pub app: &'a AppContext,
901}
902
903#[derive(Clone, Copy, Debug, Default, Eq, PartialEq)]
904pub enum Axis {
905 #[default]
906 Horizontal,
907 Vertical,
908}
909
910impl Axis {
911 pub fn invert(self) -> Self {
912 match self {
913 Self::Horizontal => Self::Vertical,
914 Self::Vertical => Self::Horizontal,
915 }
916 }
917
918 pub fn component(&self, point: Vector2F) -> f32 {
919 match self {
920 Self::Horizontal => point.x(),
921 Self::Vertical => point.y(),
922 }
923 }
924}
925
926impl ToJson for Axis {
927 fn to_json(&self) -> serde_json::Value {
928 match self {
929 Axis::Horizontal => json!("horizontal"),
930 Axis::Vertical => json!("vertical"),
931 }
932 }
933}
934
935impl Bind for Axis {
936 fn bind(&self, statement: &Statement, start_index: i32) -> anyhow::Result<i32> {
937 match self {
938 Axis::Horizontal => "Horizontal",
939 Axis::Vertical => "Vertical",
940 }
941 .bind(statement, start_index)
942 }
943}
944
945impl Column for Axis {
946 fn column(statement: &mut Statement, start_index: i32) -> anyhow::Result<(Self, i32)> {
947 String::column(statement, start_index).and_then(|(axis_text, next_index)| {
948 Ok((
949 match axis_text.as_str() {
950 "Horizontal" => Axis::Horizontal,
951 "Vertical" => Axis::Vertical,
952 _ => bail!("Stored serialized item kind is incorrect"),
953 },
954 next_index,
955 ))
956 })
957 }
958}
959
960pub trait Vector2FExt {
961 fn along(self, axis: Axis) -> f32;
962}
963
964impl Vector2FExt for Vector2F {
965 fn along(self, axis: Axis) -> f32 {
966 match axis {
967 Axis::Horizontal => self.x(),
968 Axis::Vertical => self.y(),
969 }
970 }
971}
972
973#[derive(Copy, Clone, Debug)]
974pub struct SizeConstraint {
975 pub min: Vector2F,
976 pub max: Vector2F,
977}
978
979impl SizeConstraint {
980 pub fn new(min: Vector2F, max: Vector2F) -> Self {
981 Self { min, max }
982 }
983
984 pub fn strict(size: Vector2F) -> Self {
985 Self {
986 min: size,
987 max: size,
988 }
989 }
990
991 pub fn strict_along(axis: Axis, max: f32) -> Self {
992 match axis {
993 Axis::Horizontal => Self {
994 min: vec2f(max, 0.0),
995 max: vec2f(max, f32::INFINITY),
996 },
997 Axis::Vertical => Self {
998 min: vec2f(0.0, max),
999 max: vec2f(f32::INFINITY, max),
1000 },
1001 }
1002 }
1003
1004 pub fn max_along(&self, axis: Axis) -> f32 {
1005 match axis {
1006 Axis::Horizontal => self.max.x(),
1007 Axis::Vertical => self.max.y(),
1008 }
1009 }
1010
1011 pub fn min_along(&self, axis: Axis) -> f32 {
1012 match axis {
1013 Axis::Horizontal => self.min.x(),
1014 Axis::Vertical => self.min.y(),
1015 }
1016 }
1017
1018 pub fn constrain(&self, size: Vector2F) -> Vector2F {
1019 vec2f(
1020 size.x().min(self.max.x()).max(self.min.x()),
1021 size.y().min(self.max.y()).max(self.min.y()),
1022 )
1023 }
1024}
1025
1026impl Default for SizeConstraint {
1027 fn default() -> Self {
1028 SizeConstraint {
1029 min: Vector2F::zero(),
1030 max: Vector2F::splat(f32::INFINITY),
1031 }
1032 }
1033}
1034
1035impl ToJson for SizeConstraint {
1036 fn to_json(&self) -> serde_json::Value {
1037 json!({
1038 "min": self.min.to_json(),
1039 "max": self.max.to_json(),
1040 })
1041 }
1042}
1043
1044pub struct ChildView {
1045 view: AnyWeakViewHandle,
1046 view_name: &'static str,
1047}
1048
1049impl ChildView {
1050 pub fn new(view: impl Into<AnyViewHandle>, cx: &AppContext) -> Self {
1051 let view = view.into();
1052 let view_name = cx.view_ui_name(view.window_id(), view.id()).unwrap();
1053 Self {
1054 view: view.downgrade(),
1055 view_name,
1056 }
1057 }
1058}
1059
1060impl Element for ChildView {
1061 type LayoutState = bool;
1062 type PaintState = ();
1063
1064 fn layout(
1065 &mut self,
1066 constraint: SizeConstraint,
1067 cx: &mut LayoutContext,
1068 ) -> (Vector2F, Self::LayoutState) {
1069 if cx.rendered_views.contains_key(&self.view.id()) {
1070 let size = cx.layout(self.view.id(), constraint);
1071 (size, true)
1072 } else {
1073 log::error!(
1074 "layout called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1075 self.view.id(),
1076 self.view_name
1077 );
1078 (Vector2F::zero(), false)
1079 }
1080 }
1081
1082 fn paint(
1083 &mut self,
1084 bounds: RectF,
1085 visible_bounds: RectF,
1086 view_is_valid: &mut Self::LayoutState,
1087 cx: &mut PaintContext,
1088 ) {
1089 if *view_is_valid {
1090 cx.paint(self.view.id(), bounds.origin(), visible_bounds);
1091 } else {
1092 log::error!(
1093 "paint called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1094 self.view.id(),
1095 self.view_name
1096 );
1097 }
1098 }
1099
1100 fn rect_for_text_range(
1101 &self,
1102 range_utf16: Range<usize>,
1103 _: RectF,
1104 _: RectF,
1105 view_is_valid: &Self::LayoutState,
1106 _: &Self::PaintState,
1107 cx: &MeasurementContext,
1108 ) -> Option<RectF> {
1109 if *view_is_valid {
1110 cx.rect_for_text_range(self.view.id(), range_utf16)
1111 } else {
1112 log::error!(
1113 "rect_for_text_range called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1114 self.view.id(),
1115 self.view_name
1116 );
1117 None
1118 }
1119 }
1120
1121 fn debug(
1122 &self,
1123 bounds: RectF,
1124 _: &Self::LayoutState,
1125 _: &Self::PaintState,
1126 cx: &DebugContext,
1127 ) -> serde_json::Value {
1128 json!({
1129 "type": "ChildView",
1130 "view_id": self.view.id(),
1131 "bounds": bounds.to_json(),
1132 "view": if let Some(view) = self.view.upgrade(cx.app) {
1133 view.debug_json(cx.app)
1134 } else {
1135 json!(null)
1136 },
1137 "child": if let Some(view) = cx.rendered_views.get(&self.view.id()) {
1138 view.debug(cx)
1139 } else {
1140 json!(null)
1141 }
1142 })
1143 }
1144}