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 let t0 = std::time::Instant::now();
321 let is_topmost_window =
322 cx.is_topmost_window_for_position(self.window_id, *position);
323 println!("is_topmost_window => {:?}", t0.elapsed());
324 if is_topmost_window {
325 let t1 = std::time::Instant::now();
326 cx.platform().set_cursor_style(style_to_assign);
327 println!("set_cursor_style => {:?}", t1.elapsed());
328 }
329
330 if !event_reused {
331 if pressed_button.is_some() {
332 mouse_events.push(MouseEvent::Drag(MouseDrag {
333 region: Default::default(),
334 prev_mouse_position: self.mouse_position,
335 platform_event: e.clone(),
336 }));
337 } else if let Some(clicked_button) = self.clicked_button {
338 // Mouse up event happened outside the current window. Simulate mouse up button event
339 let button_event = e.to_button_event(clicked_button);
340 mouse_events.push(MouseEvent::Up(MouseUp {
341 region: Default::default(),
342 platform_event: button_event.clone(),
343 }));
344 mouse_events.push(MouseEvent::UpOut(MouseUpOut {
345 region: Default::default(),
346 platform_event: button_event.clone(),
347 }));
348 mouse_events.push(MouseEvent::Click(MouseClick {
349 region: Default::default(),
350 platform_event: button_event.clone(),
351 }));
352 }
353
354 mouse_events.push(MouseEvent::Move(MouseMove {
355 region: Default::default(),
356 platform_event: e.clone(),
357 }));
358 }
359
360 mouse_events.push(MouseEvent::Hover(MouseHover {
361 region: Default::default(),
362 platform_event: e.clone(),
363 started: false,
364 }));
365 mouse_events.push(MouseEvent::MoveOut(MouseMoveOut {
366 region: Default::default(),
367 }));
368
369 self.last_mouse_moved_event = Some(event.clone());
370 }
371
372 Event::MouseExited(event) => {
373 // When the platform sends a MouseExited event, synthesize
374 // a MouseMoved event whose position is outside the window's
375 // bounds so that hover and cursor state can be updated.
376 return self.dispatch_event(
377 Event::MouseMoved(MouseMovedEvent {
378 position: event.position,
379 pressed_button: event.pressed_button,
380 modifiers: event.modifiers,
381 }),
382 event_reused,
383 cx,
384 );
385 }
386
387 Event::ScrollWheel(e) => mouse_events.push(MouseEvent::ScrollWheel(MouseScrollWheel {
388 region: Default::default(),
389 platform_event: e.clone(),
390 })),
391 }
392
393 if let Some(position) = event.position() {
394 self.mouse_position = position;
395 }
396
397 // 2. Dispatch mouse events on regions
398 let mut any_event_handled = false;
399 for mut mouse_event in mouse_events {
400 let mut valid_regions = Vec::new();
401
402 // GPUI elements are arranged by z_index but sibling elements can register overlapping
403 // mouse regions. As such, hover events are only fired on overlapping elements which
404 // are at the same z-index as the topmost element which overlaps with the mouse.
405 match &mouse_event {
406 MouseEvent::Hover(_) => {
407 let mut highest_z_index = None;
408 let mouse_position = self.mouse_position.clone();
409 for (region, z_index) in self.mouse_regions.iter().rev() {
410 // Allow mouse regions to appear transparent to hovers
411 if !region.hoverable {
412 continue;
413 }
414
415 let contains_mouse = region.bounds.contains_point(mouse_position);
416
417 if contains_mouse && highest_z_index.is_none() {
418 highest_z_index = Some(z_index);
419 }
420
421 // This unwrap relies on short circuiting boolean expressions
422 // The right side of the && is only executed when contains_mouse
423 // is true, and we know above that when contains_mouse is true
424 // highest_z_index is set.
425 if contains_mouse && z_index == highest_z_index.unwrap() {
426 //Ensure that hover entrance events aren't sent twice
427 if self.hovered_region_ids.insert(region.id()) {
428 valid_regions.push(region.clone());
429 if region.notify_on_hover {
430 notified_views.insert(region.id().view_id());
431 }
432 }
433 } else {
434 // Ensure that hover exit events aren't sent twice
435 if self.hovered_region_ids.remove(®ion.id()) {
436 valid_regions.push(region.clone());
437 if region.notify_on_hover {
438 notified_views.insert(region.id().view_id());
439 }
440 }
441 }
442 }
443 }
444
445 MouseEvent::Down(_) | MouseEvent::Up(_) => {
446 for (region, _) in self.mouse_regions.iter().rev() {
447 if region.bounds.contains_point(self.mouse_position) {
448 valid_regions.push(region.clone());
449 if region.notify_on_click {
450 notified_views.insert(region.id().view_id());
451 }
452 }
453 }
454 }
455
456 MouseEvent::Click(e) => {
457 // Only raise click events if the released button is the same as the one stored
458 if self
459 .clicked_button
460 .map(|clicked_button| clicked_button == e.button)
461 .unwrap_or(false)
462 {
463 // Clear clicked regions and clicked button
464 let clicked_region_ids =
465 std::mem::replace(&mut self.clicked_region_ids, Default::default());
466 self.clicked_button = None;
467
468 // Find regions which still overlap with the mouse since the last MouseDown happened
469 for (mouse_region, _) in self.mouse_regions.iter().rev() {
470 if clicked_region_ids.contains(&mouse_region.id()) {
471 if mouse_region.bounds.contains_point(self.mouse_position) {
472 valid_regions.push(mouse_region.clone());
473 }
474 }
475 }
476 }
477 }
478
479 MouseEvent::Drag(_) => {
480 for (mouse_region, _) in self.mouse_regions.iter().rev() {
481 if self.clicked_region_ids.contains(&mouse_region.id()) {
482 valid_regions.push(mouse_region.clone());
483 }
484 }
485 }
486
487 MouseEvent::MoveOut(_) | MouseEvent::UpOut(_) | MouseEvent::DownOut(_) => {
488 for (mouse_region, _) in self.mouse_regions.iter().rev() {
489 // NOT contains
490 if !mouse_region.bounds.contains_point(self.mouse_position) {
491 valid_regions.push(mouse_region.clone());
492 }
493 }
494 }
495
496 _ => {
497 for (mouse_region, _) in self.mouse_regions.iter().rev() {
498 // Contains
499 if mouse_region.bounds.contains_point(self.mouse_position) {
500 valid_regions.push(mouse_region.clone());
501 }
502 }
503 }
504 }
505
506 //3. Fire region events
507 let hovered_region_ids = self.hovered_region_ids.clone();
508 for valid_region in valid_regions.into_iter() {
509 let mut event_cx = self.build_event_context(&mut notified_views, cx);
510
511 mouse_event.set_region(valid_region.bounds);
512 if let MouseEvent::Hover(e) = &mut mouse_event {
513 e.started = hovered_region_ids.contains(&valid_region.id())
514 }
515 // Handle Down events if the MouseRegion has a Click or Drag handler. This makes the api more intuitive as you would
516 // not expect a MouseRegion to be transparent to Down events if it also has a Click handler.
517 // This behavior can be overridden by adding a Down handler that calls cx.propogate_event
518 if let MouseEvent::Down(e) = &mouse_event {
519 if valid_region
520 .handlers
521 .contains(MouseEvent::click_disc(), Some(e.button))
522 || valid_region
523 .handlers
524 .contains(MouseEvent::drag_disc(), Some(e.button))
525 {
526 event_cx.handled = true;
527 }
528 }
529
530 // `event_consumed` should only be true if there are any handlers for this event.
531 let mut event_consumed = event_cx.handled;
532 if let Some(callbacks) = valid_region.handlers.get(&mouse_event.handler_key()) {
533 event_consumed = true;
534 for callback in callbacks {
535 event_cx.handled = true;
536 event_cx.with_current_view(valid_region.id().view_id(), {
537 let region_event = mouse_event.clone();
538 |cx| callback(region_event, cx)
539 });
540 event_consumed &= event_cx.handled;
541 any_event_handled |= event_cx.handled;
542 }
543 }
544
545 any_event_handled |= event_cx.handled;
546
547 // For bubbling events, if the event was handled, don't continue dispatching.
548 // This only makes sense for local events which return false from is_capturable.
549 if event_consumed && mouse_event.is_capturable() {
550 break;
551 }
552 }
553 }
554
555 for view_id in notified_views {
556 cx.notify_view(self.window_id, view_id);
557 }
558
559 any_event_handled
560 }
561
562 pub fn build_event_context<'a>(
563 &'a mut self,
564 notified_views: &'a mut HashSet<usize>,
565 cx: &'a mut MutableAppContext,
566 ) -> EventContext<'a> {
567 EventContext {
568 font_cache: &self.font_cache,
569 text_layout_cache: &self.text_layout_cache,
570 view_stack: Default::default(),
571 notified_views,
572 notify_count: 0,
573 handled: false,
574 window_id: self.window_id,
575 app: cx,
576 }
577 }
578
579 pub fn debug_elements(&self, cx: &AppContext) -> Option<json::Value> {
580 let view = cx.root_view(self.window_id)?;
581 Some(json!({
582 "root_view": view.debug_json(cx),
583 "root_element": self.rendered_views.get(&view.id())
584 .map(|root_element| {
585 root_element.debug(&DebugContext {
586 rendered_views: &self.rendered_views,
587 font_cache: &self.font_cache,
588 app: cx,
589 })
590 })
591 }))
592 }
593}
594
595pub struct LayoutContext<'a> {
596 window_id: usize,
597 rendered_views: &'a mut HashMap<usize, ElementBox>,
598 view_stack: Vec<usize>,
599 pub font_cache: &'a Arc<FontCache>,
600 pub font_system: Arc<dyn FontSystem>,
601 pub text_layout_cache: &'a TextLayoutCache,
602 pub asset_cache: &'a AssetCache,
603 pub app: &'a mut MutableAppContext,
604 pub refreshing: bool,
605 pub window_size: Vector2F,
606 titlebar_height: f32,
607 appearance: Appearance,
608 hovered_region_ids: HashSet<MouseRegionId>,
609 clicked_region_ids: Option<(HashSet<MouseRegionId>, MouseButton)>,
610}
611
612impl<'a> LayoutContext<'a> {
613 pub(crate) fn keystrokes_for_action(
614 &mut self,
615 action: &dyn Action,
616 ) -> Option<SmallVec<[Keystroke; 2]>> {
617 self.app
618 .keystrokes_for_action(self.window_id, &self.view_stack, action)
619 }
620
621 fn layout(&mut self, view_id: usize, constraint: SizeConstraint) -> Vector2F {
622 let print_error = |view_id| {
623 format!(
624 "{} with id {}",
625 self.app.name_for_view(self.window_id, view_id).unwrap(),
626 view_id,
627 )
628 };
629 match (
630 self.view_stack.last(),
631 self.app.parents.get(&(self.window_id, view_id)),
632 ) {
633 (Some(layout_parent), Some(ParentId::View(app_parent))) => {
634 if layout_parent != app_parent {
635 panic!(
636 "View {} was laid out with parent {} when it was constructed with parent {}",
637 print_error(view_id),
638 print_error(*layout_parent),
639 print_error(*app_parent))
640 }
641 }
642 (None, Some(ParentId::View(app_parent))) => panic!(
643 "View {} was laid out without a parent when it was constructed with parent {}",
644 print_error(view_id),
645 print_error(*app_parent)
646 ),
647 (Some(layout_parent), Some(ParentId::Root)) => panic!(
648 "View {} was laid out with parent {} when it was constructed as a window root",
649 print_error(view_id),
650 print_error(*layout_parent),
651 ),
652 (_, None) => panic!(
653 "View {} did not have a registered parent in the app context",
654 print_error(view_id),
655 ),
656 _ => {}
657 }
658
659 self.view_stack.push(view_id);
660 let mut rendered_view = self.rendered_views.remove(&view_id).unwrap();
661 let size = rendered_view.layout(constraint, self);
662 self.rendered_views.insert(view_id, rendered_view);
663 self.view_stack.pop();
664 size
665 }
666
667 pub fn render<F, V, T>(&mut self, handle: &ViewHandle<V>, f: F) -> T
668 where
669 F: FnOnce(&mut V, &mut RenderContext<V>) -> T,
670 V: View,
671 {
672 handle.update(self.app, |view, cx| {
673 let mut render_cx = RenderContext {
674 app: cx,
675 window_id: handle.window_id(),
676 view_id: handle.id(),
677 view_type: PhantomData,
678 titlebar_height: self.titlebar_height,
679 hovered_region_ids: self.hovered_region_ids.clone(),
680 clicked_region_ids: self.clicked_region_ids.clone(),
681 refreshing: self.refreshing,
682 appearance: self.appearance,
683 };
684 f(view, &mut render_cx)
685 })
686 }
687}
688
689impl<'a> Deref for LayoutContext<'a> {
690 type Target = MutableAppContext;
691
692 fn deref(&self) -> &Self::Target {
693 self.app
694 }
695}
696
697impl<'a> DerefMut for LayoutContext<'a> {
698 fn deref_mut(&mut self) -> &mut Self::Target {
699 self.app
700 }
701}
702
703impl<'a> ReadView for LayoutContext<'a> {
704 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
705 self.app.read_view(handle)
706 }
707}
708
709impl<'a> ReadModel for LayoutContext<'a> {
710 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
711 self.app.read_model(handle)
712 }
713}
714
715impl<'a> UpgradeModelHandle for LayoutContext<'a> {
716 fn upgrade_model_handle<T: Entity>(
717 &self,
718 handle: &WeakModelHandle<T>,
719 ) -> Option<ModelHandle<T>> {
720 self.app.upgrade_model_handle(handle)
721 }
722
723 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
724 self.app.model_handle_is_upgradable(handle)
725 }
726
727 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
728 self.app.upgrade_any_model_handle(handle)
729 }
730}
731
732impl<'a> UpgradeViewHandle for LayoutContext<'a> {
733 fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
734 self.app.upgrade_view_handle(handle)
735 }
736
737 fn upgrade_any_view_handle(&self, handle: &crate::AnyWeakViewHandle) -> Option<AnyViewHandle> {
738 self.app.upgrade_any_view_handle(handle)
739 }
740}
741
742pub struct PaintContext<'a> {
743 rendered_views: &'a mut HashMap<usize, ElementBox>,
744 view_stack: Vec<usize>,
745 pub window_size: Vector2F,
746 pub scene: &'a mut SceneBuilder,
747 pub font_cache: &'a FontCache,
748 pub text_layout_cache: &'a TextLayoutCache,
749 pub app: &'a AppContext,
750}
751
752impl<'a> PaintContext<'a> {
753 fn paint(&mut self, view_id: usize, origin: Vector2F, visible_bounds: RectF) {
754 if let Some(mut tree) = self.rendered_views.remove(&view_id) {
755 self.view_stack.push(view_id);
756 tree.paint(origin, visible_bounds, self);
757 self.rendered_views.insert(view_id, tree);
758 self.view_stack.pop();
759 }
760 }
761
762 #[inline]
763 pub fn paint_stacking_context<F>(
764 &mut self,
765 clip_bounds: Option<RectF>,
766 z_index: Option<usize>,
767 f: F,
768 ) where
769 F: FnOnce(&mut Self),
770 {
771 self.scene.push_stacking_context(clip_bounds, z_index);
772 f(self);
773 self.scene.pop_stacking_context();
774 }
775
776 #[inline]
777 pub fn paint_layer<F>(&mut self, clip_bounds: Option<RectF>, f: F)
778 where
779 F: FnOnce(&mut Self),
780 {
781 self.scene.push_layer(clip_bounds);
782 f(self);
783 self.scene.pop_layer();
784 }
785
786 pub fn current_view_id(&self) -> usize {
787 *self.view_stack.last().unwrap()
788 }
789}
790
791impl<'a> Deref for PaintContext<'a> {
792 type Target = AppContext;
793
794 fn deref(&self) -> &Self::Target {
795 self.app
796 }
797}
798
799pub struct EventContext<'a> {
800 pub font_cache: &'a FontCache,
801 pub text_layout_cache: &'a TextLayoutCache,
802 pub app: &'a mut MutableAppContext,
803 pub window_id: usize,
804 pub notify_count: usize,
805 view_stack: Vec<usize>,
806 handled: bool,
807 notified_views: &'a mut HashSet<usize>,
808}
809
810impl<'a> EventContext<'a> {
811 fn with_current_view<F, T>(&mut self, view_id: usize, f: F) -> T
812 where
813 F: FnOnce(&mut Self) -> T,
814 {
815 self.view_stack.push(view_id);
816 let result = f(self);
817 self.view_stack.pop();
818 result
819 }
820
821 pub fn window_id(&self) -> usize {
822 self.window_id
823 }
824
825 pub fn view_id(&self) -> Option<usize> {
826 self.view_stack.last().copied()
827 }
828
829 pub fn is_parent_view_focused(&self) -> bool {
830 if let Some(parent_view_id) = self.view_stack.last() {
831 self.app.focused_view_id(self.window_id) == Some(*parent_view_id)
832 } else {
833 false
834 }
835 }
836
837 pub fn focus_parent_view(&mut self) {
838 if let Some(parent_view_id) = self.view_stack.last() {
839 self.app.focus(self.window_id, Some(*parent_view_id))
840 }
841 }
842
843 pub fn dispatch_any_action(&mut self, action: Box<dyn Action>) {
844 self.app
845 .dispatch_any_action_at(self.window_id, *self.view_stack.last().unwrap(), action)
846 }
847
848 pub fn dispatch_action<A: Action>(&mut self, action: A) {
849 self.dispatch_any_action(Box::new(action));
850 }
851
852 pub fn notify(&mut self) {
853 self.notify_count += 1;
854 if let Some(view_id) = self.view_stack.last() {
855 self.notified_views.insert(*view_id);
856 }
857 }
858
859 pub fn notify_count(&self) -> usize {
860 self.notify_count
861 }
862
863 pub fn propagate_event(&mut self) {
864 self.handled = false;
865 }
866}
867
868impl<'a> Deref for EventContext<'a> {
869 type Target = MutableAppContext;
870
871 fn deref(&self) -> &Self::Target {
872 self.app
873 }
874}
875
876impl<'a> DerefMut for EventContext<'a> {
877 fn deref_mut(&mut self) -> &mut Self::Target {
878 self.app
879 }
880}
881
882pub struct MeasurementContext<'a> {
883 app: &'a AppContext,
884 rendered_views: &'a HashMap<usize, ElementBox>,
885 pub window_id: usize,
886}
887
888impl<'a> Deref for MeasurementContext<'a> {
889 type Target = AppContext;
890
891 fn deref(&self) -> &Self::Target {
892 self.app
893 }
894}
895
896impl<'a> MeasurementContext<'a> {
897 fn rect_for_text_range(&self, view_id: usize, range_utf16: Range<usize>) -> Option<RectF> {
898 let element = self.rendered_views.get(&view_id)?;
899 element.rect_for_text_range(range_utf16, self)
900 }
901}
902
903pub struct DebugContext<'a> {
904 rendered_views: &'a HashMap<usize, ElementBox>,
905 pub font_cache: &'a FontCache,
906 pub app: &'a AppContext,
907}
908
909#[derive(Clone, Copy, Debug, Default, Eq, PartialEq)]
910pub enum Axis {
911 #[default]
912 Horizontal,
913 Vertical,
914}
915
916impl Axis {
917 pub fn invert(self) -> Self {
918 match self {
919 Self::Horizontal => Self::Vertical,
920 Self::Vertical => Self::Horizontal,
921 }
922 }
923
924 pub fn component(&self, point: Vector2F) -> f32 {
925 match self {
926 Self::Horizontal => point.x(),
927 Self::Vertical => point.y(),
928 }
929 }
930}
931
932impl ToJson for Axis {
933 fn to_json(&self) -> serde_json::Value {
934 match self {
935 Axis::Horizontal => json!("horizontal"),
936 Axis::Vertical => json!("vertical"),
937 }
938 }
939}
940
941impl Bind for Axis {
942 fn bind(&self, statement: &Statement, start_index: i32) -> anyhow::Result<i32> {
943 match self {
944 Axis::Horizontal => "Horizontal",
945 Axis::Vertical => "Vertical",
946 }
947 .bind(statement, start_index)
948 }
949}
950
951impl Column for Axis {
952 fn column(statement: &mut Statement, start_index: i32) -> anyhow::Result<(Self, i32)> {
953 String::column(statement, start_index).and_then(|(axis_text, next_index)| {
954 Ok((
955 match axis_text.as_str() {
956 "Horizontal" => Axis::Horizontal,
957 "Vertical" => Axis::Vertical,
958 _ => bail!("Stored serialized item kind is incorrect"),
959 },
960 next_index,
961 ))
962 })
963 }
964}
965
966pub trait Vector2FExt {
967 fn along(self, axis: Axis) -> f32;
968}
969
970impl Vector2FExt for Vector2F {
971 fn along(self, axis: Axis) -> f32 {
972 match axis {
973 Axis::Horizontal => self.x(),
974 Axis::Vertical => self.y(),
975 }
976 }
977}
978
979#[derive(Copy, Clone, Debug)]
980pub struct SizeConstraint {
981 pub min: Vector2F,
982 pub max: Vector2F,
983}
984
985impl SizeConstraint {
986 pub fn new(min: Vector2F, max: Vector2F) -> Self {
987 Self { min, max }
988 }
989
990 pub fn strict(size: Vector2F) -> Self {
991 Self {
992 min: size,
993 max: size,
994 }
995 }
996
997 pub fn strict_along(axis: Axis, max: f32) -> Self {
998 match axis {
999 Axis::Horizontal => Self {
1000 min: vec2f(max, 0.0),
1001 max: vec2f(max, f32::INFINITY),
1002 },
1003 Axis::Vertical => Self {
1004 min: vec2f(0.0, max),
1005 max: vec2f(f32::INFINITY, max),
1006 },
1007 }
1008 }
1009
1010 pub fn max_along(&self, axis: Axis) -> f32 {
1011 match axis {
1012 Axis::Horizontal => self.max.x(),
1013 Axis::Vertical => self.max.y(),
1014 }
1015 }
1016
1017 pub fn min_along(&self, axis: Axis) -> f32 {
1018 match axis {
1019 Axis::Horizontal => self.min.x(),
1020 Axis::Vertical => self.min.y(),
1021 }
1022 }
1023
1024 pub fn constrain(&self, size: Vector2F) -> Vector2F {
1025 vec2f(
1026 size.x().min(self.max.x()).max(self.min.x()),
1027 size.y().min(self.max.y()).max(self.min.y()),
1028 )
1029 }
1030}
1031
1032impl Default for SizeConstraint {
1033 fn default() -> Self {
1034 SizeConstraint {
1035 min: Vector2F::zero(),
1036 max: Vector2F::splat(f32::INFINITY),
1037 }
1038 }
1039}
1040
1041impl ToJson for SizeConstraint {
1042 fn to_json(&self) -> serde_json::Value {
1043 json!({
1044 "min": self.min.to_json(),
1045 "max": self.max.to_json(),
1046 })
1047 }
1048}
1049
1050pub struct ChildView {
1051 view: AnyWeakViewHandle,
1052 view_name: &'static str,
1053}
1054
1055impl ChildView {
1056 pub fn new(view: impl Into<AnyViewHandle>, cx: &AppContext) -> Self {
1057 let view = view.into();
1058 let view_name = cx.view_ui_name(view.window_id(), view.id()).unwrap();
1059 Self {
1060 view: view.downgrade(),
1061 view_name,
1062 }
1063 }
1064}
1065
1066impl Element for ChildView {
1067 type LayoutState = bool;
1068 type PaintState = ();
1069
1070 fn layout(
1071 &mut self,
1072 constraint: SizeConstraint,
1073 cx: &mut LayoutContext,
1074 ) -> (Vector2F, Self::LayoutState) {
1075 if cx.rendered_views.contains_key(&self.view.id()) {
1076 let size = cx.layout(self.view.id(), constraint);
1077 (size, true)
1078 } else {
1079 log::error!(
1080 "layout called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1081 self.view.id(),
1082 self.view_name
1083 );
1084 (Vector2F::zero(), false)
1085 }
1086 }
1087
1088 fn paint(
1089 &mut self,
1090 bounds: RectF,
1091 visible_bounds: RectF,
1092 view_is_valid: &mut Self::LayoutState,
1093 cx: &mut PaintContext,
1094 ) {
1095 if *view_is_valid {
1096 cx.paint(self.view.id(), bounds.origin(), visible_bounds);
1097 } else {
1098 log::error!(
1099 "paint called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1100 self.view.id(),
1101 self.view_name
1102 );
1103 }
1104 }
1105
1106 fn rect_for_text_range(
1107 &self,
1108 range_utf16: Range<usize>,
1109 _: RectF,
1110 _: RectF,
1111 view_is_valid: &Self::LayoutState,
1112 _: &Self::PaintState,
1113 cx: &MeasurementContext,
1114 ) -> Option<RectF> {
1115 if *view_is_valid {
1116 cx.rect_for_text_range(self.view.id(), range_utf16)
1117 } else {
1118 log::error!(
1119 "rect_for_text_range called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1120 self.view.id(),
1121 self.view_name
1122 );
1123 None
1124 }
1125 }
1126
1127 fn debug(
1128 &self,
1129 bounds: RectF,
1130 _: &Self::LayoutState,
1131 _: &Self::PaintState,
1132 cx: &DebugContext,
1133 ) -> serde_json::Value {
1134 json!({
1135 "type": "ChildView",
1136 "view_id": self.view.id(),
1137 "bounds": bounds.to_json(),
1138 "view": if let Some(view) = self.view.upgrade(cx.app) {
1139 view.debug_json(cx.app)
1140 } else {
1141 json!(null)
1142 },
1143 "child": if let Some(view) = cx.rendered_views.get(&self.view.id()) {
1144 view.debug(cx)
1145 } else {
1146 json!(null)
1147 }
1148 })
1149 }
1150}