1use crate::{
2 app::{AppContext, MutableAppContext, WindowInvalidation},
3 elements::Element,
4 font_cache::FontCache,
5 geometry::rect::RectF,
6 json::{self, ToJson},
7 platform::{CursorStyle, Event},
8 scene::{
9 CursorRegion, MouseClick, MouseDown, MouseDownOut, MouseDrag, MouseEvent, MouseHover,
10 MouseMove, MouseMoveOut, MouseScrollWheel, MouseUp, MouseUpOut, Scene,
11 },
12 text_layout::TextLayoutCache,
13 Action, AnyModelHandle, AnyViewHandle, AnyWeakModelHandle, AnyWeakViewHandle, Appearance,
14 AssetCache, ElementBox, Entity, FontSystem, ModelHandle, MouseButton, MouseMovedEvent,
15 MouseRegion, MouseRegionId, ParentId, ReadModel, ReadView, RenderContext, RenderParams,
16 SceneBuilder, UpgradeModelHandle, UpgradeViewHandle, View, ViewHandle, WeakModelHandle,
17 WeakViewHandle,
18};
19use anyhow::bail;
20use collections::{HashMap, HashSet};
21use pathfinder_geometry::vector::{vec2f, Vector2F};
22use serde_json::json;
23use smallvec::SmallVec;
24use sqlez::{
25 bindable::{Bind, Column, StaticColumnCount},
26 statement::Statement,
27};
28use std::{
29 marker::PhantomData,
30 ops::{Deref, DerefMut, Range},
31 sync::Arc,
32};
33
34pub struct Presenter {
35 window_id: usize,
36 pub(crate) rendered_views: HashMap<usize, ElementBox>,
37 cursor_regions: Vec<CursorRegion>,
38 mouse_regions: Vec<(MouseRegion, usize)>,
39 font_cache: Arc<FontCache>,
40 text_layout_cache: TextLayoutCache,
41 asset_cache: Arc<AssetCache>,
42 last_mouse_moved_event: Option<Event>,
43 hovered_region_ids: HashSet<MouseRegionId>,
44 clicked_region_ids: HashSet<MouseRegionId>,
45 clicked_button: Option<MouseButton>,
46 mouse_position: Vector2F,
47 titlebar_height: f32,
48 appearance: Appearance,
49}
50
51impl Presenter {
52 pub fn new(
53 window_id: usize,
54 titlebar_height: f32,
55 appearance: Appearance,
56 font_cache: Arc<FontCache>,
57 text_layout_cache: TextLayoutCache,
58 asset_cache: Arc<AssetCache>,
59 cx: &mut MutableAppContext,
60 ) -> Self {
61 Self {
62 window_id,
63 rendered_views: cx.render_views(window_id, titlebar_height, appearance),
64 cursor_regions: Default::default(),
65 mouse_regions: Default::default(),
66 font_cache,
67 text_layout_cache,
68 asset_cache,
69 last_mouse_moved_event: None,
70 hovered_region_ids: Default::default(),
71 clicked_region_ids: Default::default(),
72 clicked_button: None,
73 mouse_position: vec2f(0., 0.),
74 titlebar_height,
75 appearance,
76 }
77 }
78
79 pub fn invalidate(
80 &mut self,
81 invalidation: &mut WindowInvalidation,
82 appearance: Appearance,
83 cx: &mut MutableAppContext,
84 ) {
85 cx.start_frame();
86 self.appearance = appearance;
87 for view_id in &invalidation.removed {
88 invalidation.updated.remove(view_id);
89 self.rendered_views.remove(view_id);
90 }
91 for view_id in &invalidation.updated {
92 self.rendered_views.insert(
93 *view_id,
94 cx.render_view(RenderParams {
95 window_id: self.window_id,
96 view_id: *view_id,
97 titlebar_height: self.titlebar_height,
98 hovered_region_ids: self.hovered_region_ids.clone(),
99 clicked_region_ids: self
100 .clicked_button
101 .map(|button| (self.clicked_region_ids.clone(), button)),
102 refreshing: false,
103 appearance,
104 })
105 .unwrap(),
106 );
107 }
108 }
109
110 pub fn refresh(
111 &mut self,
112 invalidation: &mut WindowInvalidation,
113 appearance: Appearance,
114 cx: &mut MutableAppContext,
115 ) {
116 self.invalidate(invalidation, appearance, cx);
117 for (view_id, view) in &mut self.rendered_views {
118 if !invalidation.updated.contains(view_id) {
119 *view = cx
120 .render_view(RenderParams {
121 window_id: self.window_id,
122 view_id: *view_id,
123 titlebar_height: self.titlebar_height,
124 hovered_region_ids: self.hovered_region_ids.clone(),
125 clicked_region_ids: self
126 .clicked_button
127 .map(|button| (self.clicked_region_ids.clone(), button)),
128 refreshing: true,
129 appearance,
130 })
131 .unwrap();
132 }
133 }
134 }
135
136 pub fn build_scene(
137 &mut self,
138 window_size: Vector2F,
139 scale_factor: f32,
140 refreshing: bool,
141 cx: &mut MutableAppContext,
142 ) -> Scene {
143 let mut scene_builder = SceneBuilder::new(scale_factor);
144
145 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
146 self.layout(window_size, refreshing, cx);
147 let mut paint_cx = self.build_paint_context(&mut scene_builder, window_size, cx);
148 paint_cx.paint(
149 root_view_id,
150 Vector2F::zero(),
151 RectF::new(Vector2F::zero(), window_size),
152 );
153 self.text_layout_cache.finish_frame();
154 let scene = scene_builder.build();
155 self.cursor_regions = scene.cursor_regions();
156 self.mouse_regions = scene.mouse_regions();
157
158 // window.is_topmost for the mouse moved event's postion?
159 if cx.window_is_active(self.window_id) {
160 if let Some(event) = self.last_mouse_moved_event.clone() {
161 self.dispatch_event(event, true, cx);
162 }
163 }
164
165 scene
166 } else {
167 log::error!("could not find root_view_id for window {}", self.window_id);
168 scene_builder.build()
169 }
170 }
171
172 fn layout(&mut self, window_size: Vector2F, refreshing: bool, cx: &mut MutableAppContext) {
173 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
174 self.build_layout_context(window_size, refreshing, cx)
175 .layout(root_view_id, SizeConstraint::strict(window_size));
176 }
177 }
178
179 pub fn build_layout_context<'a>(
180 &'a mut self,
181 window_size: Vector2F,
182 refreshing: bool,
183 cx: &'a mut MutableAppContext,
184 ) -> LayoutContext<'a> {
185 LayoutContext {
186 window_id: self.window_id,
187 rendered_views: &mut self.rendered_views,
188 font_cache: &self.font_cache,
189 font_system: cx.platform().fonts(),
190 text_layout_cache: &self.text_layout_cache,
191 asset_cache: &self.asset_cache,
192 view_stack: Vec::new(),
193 refreshing,
194 hovered_region_ids: self.hovered_region_ids.clone(),
195 clicked_region_ids: self
196 .clicked_button
197 .map(|button| (self.clicked_region_ids.clone(), button)),
198 titlebar_height: self.titlebar_height,
199 appearance: self.appearance,
200 window_size,
201 app: cx,
202 }
203 }
204
205 pub fn build_paint_context<'a>(
206 &'a mut self,
207 scene: &'a mut SceneBuilder,
208 window_size: Vector2F,
209 cx: &'a mut MutableAppContext,
210 ) -> PaintContext {
211 PaintContext {
212 scene,
213 window_size,
214 font_cache: &self.font_cache,
215 text_layout_cache: &self.text_layout_cache,
216 rendered_views: &mut self.rendered_views,
217 view_stack: Vec::new(),
218 app: cx,
219 }
220 }
221
222 pub fn rect_for_text_range(&self, range_utf16: Range<usize>, cx: &AppContext) -> Option<RectF> {
223 cx.focused_view_id(self.window_id).and_then(|view_id| {
224 let cx = MeasurementContext {
225 app: cx,
226 rendered_views: &self.rendered_views,
227 window_id: self.window_id,
228 };
229 cx.rect_for_text_range(view_id, range_utf16)
230 })
231 }
232
233 pub fn dispatch_event(
234 &mut self,
235 event: Event,
236 event_reused: bool,
237 cx: &mut MutableAppContext,
238 ) -> bool {
239 let mut mouse_events = SmallVec::<[_; 2]>::new();
240 let mut notified_views: HashSet<usize> = Default::default();
241
242 // 1. Handle platform event. Keyboard events get dispatched immediately, while mouse events
243 // get mapped into the mouse-specific MouseEvent type.
244 // -> These are usually small: [Mouse Down] or [Mouse up, Click] or [Mouse Moved, Mouse Dragged?]
245 // -> Also updates mouse-related state
246 match &event {
247 Event::KeyDown(e) => return cx.dispatch_key_down(self.window_id, e),
248
249 Event::KeyUp(e) => return cx.dispatch_key_up(self.window_id, e),
250
251 Event::ModifiersChanged(e) => return cx.dispatch_modifiers_changed(self.window_id, e),
252
253 Event::MouseDown(e) => {
254 // Click events are weird because they can be fired after a drag event.
255 // MDN says that browsers handle this by starting from 'the most
256 // specific ancestor element that contained both [positions]'
257 // So we need to store the overlapping regions on mouse down.
258
259 // If there is already clicked_button stored, don't replace it.
260 if self.clicked_button.is_none() {
261 self.clicked_region_ids = self
262 .mouse_regions
263 .iter()
264 .filter_map(|(region, _)| {
265 if region.bounds.contains_point(e.position) {
266 Some(region.id())
267 } else {
268 None
269 }
270 })
271 .collect();
272
273 self.clicked_button = Some(e.button);
274 }
275
276 mouse_events.push(MouseEvent::Down(MouseDown {
277 region: Default::default(),
278 platform_event: e.clone(),
279 }));
280 mouse_events.push(MouseEvent::DownOut(MouseDownOut {
281 region: Default::default(),
282 platform_event: e.clone(),
283 }));
284 }
285
286 Event::MouseUp(e) => {
287 // NOTE: The order of event pushes is important! MouseUp events MUST be fired
288 // before click events, and so the MouseUp events need to be pushed before
289 // MouseClick events.
290 mouse_events.push(MouseEvent::Up(MouseUp {
291 region: Default::default(),
292 platform_event: e.clone(),
293 }));
294 mouse_events.push(MouseEvent::UpOut(MouseUpOut {
295 region: Default::default(),
296 platform_event: e.clone(),
297 }));
298 mouse_events.push(MouseEvent::Click(MouseClick {
299 region: Default::default(),
300 platform_event: e.clone(),
301 }));
302 }
303
304 Event::MouseMoved(
305 e @ MouseMovedEvent {
306 position,
307 pressed_button,
308 ..
309 },
310 ) => {
311 let mut style_to_assign = CursorStyle::Arrow;
312 for region in self.cursor_regions.iter().rev() {
313 if region.bounds.contains_point(*position) {
314 style_to_assign = region.style;
315 break;
316 }
317 }
318
319 if cx.is_topmost_window_for_position(self.window_id, *position) {
320 cx.platform().set_cursor_style(style_to_assign);
321 }
322
323 if !event_reused {
324 if pressed_button.is_some() {
325 mouse_events.push(MouseEvent::Drag(MouseDrag {
326 region: Default::default(),
327 prev_mouse_position: self.mouse_position,
328 platform_event: e.clone(),
329 }));
330 } else if let Some(clicked_button) = self.clicked_button {
331 // Mouse up event happened outside the current window. Simulate mouse up button event
332 let button_event = e.to_button_event(clicked_button);
333 mouse_events.push(MouseEvent::Up(MouseUp {
334 region: Default::default(),
335 platform_event: button_event.clone(),
336 }));
337 mouse_events.push(MouseEvent::UpOut(MouseUpOut {
338 region: Default::default(),
339 platform_event: button_event.clone(),
340 }));
341 mouse_events.push(MouseEvent::Click(MouseClick {
342 region: Default::default(),
343 platform_event: button_event.clone(),
344 }));
345 }
346
347 mouse_events.push(MouseEvent::Move(MouseMove {
348 region: Default::default(),
349 platform_event: e.clone(),
350 }));
351 }
352
353 mouse_events.push(MouseEvent::Hover(MouseHover {
354 region: Default::default(),
355 platform_event: e.clone(),
356 started: false,
357 }));
358 mouse_events.push(MouseEvent::MoveOut(MouseMoveOut {
359 region: Default::default(),
360 }));
361
362 self.last_mouse_moved_event = Some(event.clone());
363 }
364
365 Event::MouseExited(event) => {
366 // When the platform sends a MouseExited event, synthesize
367 // a MouseMoved event whose position is outside the window's
368 // bounds so that hover and cursor state can be updated.
369 return self.dispatch_event(
370 Event::MouseMoved(MouseMovedEvent {
371 position: event.position,
372 pressed_button: event.pressed_button,
373 modifiers: event.modifiers,
374 }),
375 event_reused,
376 cx,
377 );
378 }
379
380 Event::ScrollWheel(e) => mouse_events.push(MouseEvent::ScrollWheel(MouseScrollWheel {
381 region: Default::default(),
382 platform_event: e.clone(),
383 })),
384 }
385
386 if let Some(position) = event.position() {
387 self.mouse_position = position;
388 }
389
390 // 2. Dispatch mouse events on regions
391 let mut any_event_handled = false;
392 for mut mouse_event in mouse_events {
393 let mut valid_regions = Vec::new();
394
395 // GPUI elements are arranged by z_index but sibling elements can register overlapping
396 // mouse regions. As such, hover events are only fired on overlapping elements which
397 // are at the same z-index as the topmost element which overlaps with the mouse.
398 match &mouse_event {
399 MouseEvent::Hover(_) => {
400 let mut highest_z_index = None;
401 let mouse_position = self.mouse_position.clone();
402 for (region, z_index) in self.mouse_regions.iter().rev() {
403 // Allow mouse regions to appear transparent to hovers
404 if !region.hoverable {
405 continue;
406 }
407
408 let contains_mouse = region.bounds.contains_point(mouse_position);
409
410 if contains_mouse && highest_z_index.is_none() {
411 highest_z_index = Some(z_index);
412 }
413
414 // This unwrap relies on short circuiting boolean expressions
415 // The right side of the && is only executed when contains_mouse
416 // is true, and we know above that when contains_mouse is true
417 // highest_z_index is set.
418 if contains_mouse && z_index == highest_z_index.unwrap() {
419 //Ensure that hover entrance events aren't sent twice
420 if self.hovered_region_ids.insert(region.id()) {
421 valid_regions.push(region.clone());
422 if region.notify_on_hover {
423 notified_views.insert(region.id().view_id());
424 }
425 }
426 } else {
427 // Ensure that hover exit events aren't sent twice
428 if self.hovered_region_ids.remove(®ion.id()) {
429 valid_regions.push(region.clone());
430 if region.notify_on_hover {
431 notified_views.insert(region.id().view_id());
432 }
433 }
434 }
435 }
436 }
437
438 MouseEvent::Down(_) | MouseEvent::Up(_) => {
439 for (region, _) in self.mouse_regions.iter().rev() {
440 if region.bounds.contains_point(self.mouse_position) {
441 valid_regions.push(region.clone());
442 if region.notify_on_click {
443 notified_views.insert(region.id().view_id());
444 }
445 }
446 }
447 }
448
449 MouseEvent::Click(e) => {
450 // Only raise click events if the released button is the same as the one stored
451 if self
452 .clicked_button
453 .map(|clicked_button| clicked_button == e.button)
454 .unwrap_or(false)
455 {
456 // Clear clicked regions and clicked button
457 let clicked_region_ids =
458 std::mem::replace(&mut self.clicked_region_ids, Default::default());
459 self.clicked_button = None;
460
461 // Find regions which still overlap with the mouse since the last MouseDown happened
462 for (mouse_region, _) in self.mouse_regions.iter().rev() {
463 if clicked_region_ids.contains(&mouse_region.id()) {
464 if mouse_region.bounds.contains_point(self.mouse_position) {
465 valid_regions.push(mouse_region.clone());
466 }
467 }
468 }
469 }
470 }
471
472 MouseEvent::Drag(_) => {
473 for (mouse_region, _) in self.mouse_regions.iter().rev() {
474 if self.clicked_region_ids.contains(&mouse_region.id()) {
475 valid_regions.push(mouse_region.clone());
476 }
477 }
478 }
479
480 MouseEvent::MoveOut(_) | MouseEvent::UpOut(_) | MouseEvent::DownOut(_) => {
481 for (mouse_region, _) in self.mouse_regions.iter().rev() {
482 // NOT contains
483 if !mouse_region.bounds.contains_point(self.mouse_position) {
484 valid_regions.push(mouse_region.clone());
485 }
486 }
487 }
488
489 _ => {
490 for (mouse_region, _) in self.mouse_regions.iter().rev() {
491 // Contains
492 if mouse_region.bounds.contains_point(self.mouse_position) {
493 valid_regions.push(mouse_region.clone());
494 }
495 }
496 }
497 }
498
499 //3. Fire region events
500 let hovered_region_ids = self.hovered_region_ids.clone();
501 for valid_region in valid_regions.into_iter() {
502 let mut event_cx = self.build_event_context(&mut notified_views, cx);
503
504 mouse_event.set_region(valid_region.bounds);
505 if let MouseEvent::Hover(e) = &mut mouse_event {
506 e.started = hovered_region_ids.contains(&valid_region.id())
507 }
508 // Handle Down events if the MouseRegion has a Click or Drag handler. This makes the api more intuitive as you would
509 // not expect a MouseRegion to be transparent to Down events if it also has a Click handler.
510 // This behavior can be overridden by adding a Down handler
511 if let MouseEvent::Down(e) = &mouse_event {
512 let has_click = valid_region
513 .handlers
514 .contains(MouseEvent::click_disc(), Some(e.button));
515 let has_drag = valid_region
516 .handlers
517 .contains(MouseEvent::drag_disc(), Some(e.button));
518 let has_down = valid_region
519 .handlers
520 .contains(MouseEvent::down_disc(), Some(e.button));
521 if !has_down && (has_click || has_drag) {
522 event_cx.handled = true;
523 }
524 }
525
526 // `event_consumed` should only be true if there are any handlers for this event.
527 let mut event_consumed = event_cx.handled;
528 if let Some(callbacks) = valid_region.handlers.get(&mouse_event.handler_key()) {
529 for callback in callbacks {
530 event_cx.handled = true;
531 event_cx.with_current_view(valid_region.id().view_id(), {
532 let region_event = mouse_event.clone();
533 |cx| callback(region_event, cx)
534 });
535 event_consumed |= event_cx.handled;
536 any_event_handled |= event_cx.handled;
537 }
538 }
539
540 any_event_handled |= event_cx.handled;
541
542 // For bubbling events, if the event was handled, don't continue dispatching.
543 // This only makes sense for local events which return false from is_capturable.
544 if event_consumed && mouse_event.is_capturable() {
545 break;
546 }
547 }
548 }
549
550 for view_id in notified_views {
551 cx.notify_view(self.window_id, view_id);
552 }
553
554 any_event_handled
555 }
556
557 pub fn build_event_context<'a>(
558 &'a mut self,
559 notified_views: &'a mut HashSet<usize>,
560 cx: &'a mut MutableAppContext,
561 ) -> EventContext<'a> {
562 EventContext {
563 font_cache: &self.font_cache,
564 text_layout_cache: &self.text_layout_cache,
565 view_stack: Default::default(),
566 notified_views,
567 notify_count: 0,
568 handled: false,
569 window_id: self.window_id,
570 app: cx,
571 }
572 }
573
574 pub fn debug_elements(&self, cx: &AppContext) -> Option<json::Value> {
575 let view = cx.root_view(self.window_id)?;
576 Some(json!({
577 "root_view": view.debug_json(cx),
578 "root_element": self.rendered_views.get(&view.id())
579 .map(|root_element| {
580 root_element.debug(&DebugContext {
581 rendered_views: &self.rendered_views,
582 font_cache: &self.font_cache,
583 app: cx,
584 })
585 })
586 }))
587 }
588}
589
590pub struct LayoutContext<'a> {
591 window_id: usize,
592 rendered_views: &'a mut HashMap<usize, ElementBox>,
593 view_stack: Vec<usize>,
594 pub font_cache: &'a Arc<FontCache>,
595 pub font_system: Arc<dyn FontSystem>,
596 pub text_layout_cache: &'a TextLayoutCache,
597 pub asset_cache: &'a AssetCache,
598 pub app: &'a mut MutableAppContext,
599 pub refreshing: bool,
600 pub window_size: Vector2F,
601 titlebar_height: f32,
602 appearance: Appearance,
603 hovered_region_ids: HashSet<MouseRegionId>,
604 clicked_region_ids: Option<(HashSet<MouseRegionId>, MouseButton)>,
605}
606
607impl<'a> LayoutContext<'a> {
608 fn layout(&mut self, view_id: usize, constraint: SizeConstraint) -> Vector2F {
609 let print_error = |view_id| {
610 format!(
611 "{} with id {}",
612 self.app.name_for_view(self.window_id, view_id).unwrap(),
613 view_id,
614 )
615 };
616 match (
617 self.view_stack.last(),
618 self.app.parents.get(&(self.window_id, view_id)),
619 ) {
620 (Some(layout_parent), Some(ParentId::View(app_parent))) => {
621 if layout_parent != app_parent {
622 panic!(
623 "View {} was laid out with parent {} when it was constructed with parent {}",
624 print_error(view_id),
625 print_error(*layout_parent),
626 print_error(*app_parent))
627 }
628 }
629 (None, Some(ParentId::View(app_parent))) => panic!(
630 "View {} was laid out without a parent when it was constructed with parent {}",
631 print_error(view_id),
632 print_error(*app_parent)
633 ),
634 (Some(layout_parent), Some(ParentId::Root)) => panic!(
635 "View {} was laid out with parent {} when it was constructed as a window root",
636 print_error(view_id),
637 print_error(*layout_parent),
638 ),
639 (_, None) => panic!(
640 "View {} did not have a registered parent in the app context",
641 print_error(view_id),
642 ),
643 _ => {}
644 }
645
646 self.view_stack.push(view_id);
647 let mut rendered_view = self.rendered_views.remove(&view_id).unwrap();
648 let size = rendered_view.layout(constraint, self);
649 self.rendered_views.insert(view_id, rendered_view);
650 self.view_stack.pop();
651 size
652 }
653
654 pub fn render<F, V, T>(&mut self, handle: &ViewHandle<V>, f: F) -> T
655 where
656 F: FnOnce(&mut V, &mut RenderContext<V>) -> T,
657 V: View,
658 {
659 handle.update(self.app, |view, cx| {
660 let mut render_cx = RenderContext {
661 app: cx,
662 window_id: handle.window_id(),
663 view_id: handle.id(),
664 view_type: PhantomData,
665 titlebar_height: self.titlebar_height,
666 hovered_region_ids: self.hovered_region_ids.clone(),
667 clicked_region_ids: self.clicked_region_ids.clone(),
668 refreshing: self.refreshing,
669 appearance: self.appearance,
670 };
671 f(view, &mut render_cx)
672 })
673 }
674}
675
676impl<'a> Deref for LayoutContext<'a> {
677 type Target = MutableAppContext;
678
679 fn deref(&self) -> &Self::Target {
680 self.app
681 }
682}
683
684impl<'a> DerefMut for LayoutContext<'a> {
685 fn deref_mut(&mut self) -> &mut Self::Target {
686 self.app
687 }
688}
689
690impl<'a> ReadView for LayoutContext<'a> {
691 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
692 self.app.read_view(handle)
693 }
694}
695
696impl<'a> ReadModel for LayoutContext<'a> {
697 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
698 self.app.read_model(handle)
699 }
700}
701
702impl<'a> UpgradeModelHandle for LayoutContext<'a> {
703 fn upgrade_model_handle<T: Entity>(
704 &self,
705 handle: &WeakModelHandle<T>,
706 ) -> Option<ModelHandle<T>> {
707 self.app.upgrade_model_handle(handle)
708 }
709
710 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
711 self.app.model_handle_is_upgradable(handle)
712 }
713
714 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
715 self.app.upgrade_any_model_handle(handle)
716 }
717}
718
719impl<'a> UpgradeViewHandle for LayoutContext<'a> {
720 fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
721 self.app.upgrade_view_handle(handle)
722 }
723
724 fn upgrade_any_view_handle(&self, handle: &crate::AnyWeakViewHandle) -> Option<AnyViewHandle> {
725 self.app.upgrade_any_view_handle(handle)
726 }
727}
728
729pub struct PaintContext<'a> {
730 rendered_views: &'a mut HashMap<usize, ElementBox>,
731 view_stack: Vec<usize>,
732 pub window_size: Vector2F,
733 pub scene: &'a mut SceneBuilder,
734 pub font_cache: &'a FontCache,
735 pub text_layout_cache: &'a TextLayoutCache,
736 pub app: &'a AppContext,
737}
738
739impl<'a> PaintContext<'a> {
740 fn paint(&mut self, view_id: usize, origin: Vector2F, visible_bounds: RectF) {
741 if let Some(mut tree) = self.rendered_views.remove(&view_id) {
742 self.view_stack.push(view_id);
743 tree.paint(origin, visible_bounds, self);
744 self.rendered_views.insert(view_id, tree);
745 self.view_stack.pop();
746 }
747 }
748
749 #[inline]
750 pub fn paint_stacking_context<F>(
751 &mut self,
752 clip_bounds: Option<RectF>,
753 z_index: Option<usize>,
754 f: F,
755 ) where
756 F: FnOnce(&mut Self),
757 {
758 self.scene.push_stacking_context(clip_bounds, z_index);
759 f(self);
760 self.scene.pop_stacking_context();
761 }
762
763 #[inline]
764 pub fn paint_layer<F>(&mut self, clip_bounds: Option<RectF>, f: F)
765 where
766 F: FnOnce(&mut Self),
767 {
768 self.scene.push_layer(clip_bounds);
769 f(self);
770 self.scene.pop_layer();
771 }
772
773 pub fn current_view_id(&self) -> usize {
774 *self.view_stack.last().unwrap()
775 }
776}
777
778impl<'a> Deref for PaintContext<'a> {
779 type Target = AppContext;
780
781 fn deref(&self) -> &Self::Target {
782 self.app
783 }
784}
785
786pub struct EventContext<'a> {
787 pub font_cache: &'a FontCache,
788 pub text_layout_cache: &'a TextLayoutCache,
789 pub app: &'a mut MutableAppContext,
790 pub window_id: usize,
791 pub notify_count: usize,
792 view_stack: Vec<usize>,
793 handled: bool,
794 notified_views: &'a mut HashSet<usize>,
795}
796
797impl<'a> EventContext<'a> {
798 fn with_current_view<F, T>(&mut self, view_id: usize, f: F) -> T
799 where
800 F: FnOnce(&mut Self) -> T,
801 {
802 self.view_stack.push(view_id);
803 let result = f(self);
804 self.view_stack.pop();
805 result
806 }
807
808 pub fn window_id(&self) -> usize {
809 self.window_id
810 }
811
812 pub fn view_id(&self) -> Option<usize> {
813 self.view_stack.last().copied()
814 }
815
816 pub fn is_parent_view_focused(&self) -> bool {
817 if let Some(parent_view_id) = self.view_stack.last() {
818 self.app.focused_view_id(self.window_id) == Some(*parent_view_id)
819 } else {
820 false
821 }
822 }
823
824 pub fn focus_parent_view(&mut self) {
825 if let Some(parent_view_id) = self.view_stack.last() {
826 self.app.focus(self.window_id, Some(*parent_view_id))
827 }
828 }
829
830 pub fn dispatch_any_action(&mut self, action: Box<dyn Action>) {
831 self.app
832 .dispatch_any_action_at(self.window_id, *self.view_stack.last().unwrap(), action)
833 }
834
835 pub fn dispatch_action<A: Action>(&mut self, action: A) {
836 self.dispatch_any_action(Box::new(action));
837 }
838
839 pub fn notify(&mut self) {
840 self.notify_count += 1;
841 if let Some(view_id) = self.view_stack.last() {
842 self.notified_views.insert(*view_id);
843 }
844 }
845
846 pub fn notify_count(&self) -> usize {
847 self.notify_count
848 }
849
850 pub fn propagate_event(&mut self) {
851 self.handled = false;
852 }
853}
854
855impl<'a> Deref for EventContext<'a> {
856 type Target = MutableAppContext;
857
858 fn deref(&self) -> &Self::Target {
859 self.app
860 }
861}
862
863impl<'a> DerefMut for EventContext<'a> {
864 fn deref_mut(&mut self) -> &mut Self::Target {
865 self.app
866 }
867}
868
869pub struct MeasurementContext<'a> {
870 app: &'a AppContext,
871 rendered_views: &'a HashMap<usize, ElementBox>,
872 pub window_id: usize,
873}
874
875impl<'a> Deref for MeasurementContext<'a> {
876 type Target = AppContext;
877
878 fn deref(&self) -> &Self::Target {
879 self.app
880 }
881}
882
883impl<'a> MeasurementContext<'a> {
884 fn rect_for_text_range(&self, view_id: usize, range_utf16: Range<usize>) -> Option<RectF> {
885 let element = self.rendered_views.get(&view_id)?;
886 element.rect_for_text_range(range_utf16, self)
887 }
888}
889
890pub struct DebugContext<'a> {
891 rendered_views: &'a HashMap<usize, ElementBox>,
892 pub font_cache: &'a FontCache,
893 pub app: &'a AppContext,
894}
895
896#[derive(Clone, Copy, Debug, Default, Eq, PartialEq)]
897pub enum Axis {
898 #[default]
899 Horizontal,
900 Vertical,
901}
902
903impl Axis {
904 pub fn invert(self) -> Self {
905 match self {
906 Self::Horizontal => Self::Vertical,
907 Self::Vertical => Self::Horizontal,
908 }
909 }
910
911 pub fn component(&self, point: Vector2F) -> f32 {
912 match self {
913 Self::Horizontal => point.x(),
914 Self::Vertical => point.y(),
915 }
916 }
917}
918
919impl ToJson for Axis {
920 fn to_json(&self) -> serde_json::Value {
921 match self {
922 Axis::Horizontal => json!("horizontal"),
923 Axis::Vertical => json!("vertical"),
924 }
925 }
926}
927
928impl StaticColumnCount for Axis {}
929impl Bind for Axis {
930 fn bind(&self, statement: &Statement, start_index: i32) -> anyhow::Result<i32> {
931 match self {
932 Axis::Horizontal => "Horizontal",
933 Axis::Vertical => "Vertical",
934 }
935 .bind(statement, start_index)
936 }
937}
938
939impl Column for Axis {
940 fn column(statement: &mut Statement, start_index: i32) -> anyhow::Result<(Self, i32)> {
941 String::column(statement, start_index).and_then(|(axis_text, next_index)| {
942 Ok((
943 match axis_text.as_str() {
944 "Horizontal" => Axis::Horizontal,
945 "Vertical" => Axis::Vertical,
946 _ => bail!("Stored serialized item kind is incorrect"),
947 },
948 next_index,
949 ))
950 })
951 }
952}
953
954pub trait Vector2FExt {
955 fn along(self, axis: Axis) -> f32;
956}
957
958impl Vector2FExt for Vector2F {
959 fn along(self, axis: Axis) -> f32 {
960 match axis {
961 Axis::Horizontal => self.x(),
962 Axis::Vertical => self.y(),
963 }
964 }
965}
966
967#[derive(Copy, Clone, Debug)]
968pub struct SizeConstraint {
969 pub min: Vector2F,
970 pub max: Vector2F,
971}
972
973impl SizeConstraint {
974 pub fn new(min: Vector2F, max: Vector2F) -> Self {
975 Self { min, max }
976 }
977
978 pub fn strict(size: Vector2F) -> Self {
979 Self {
980 min: size,
981 max: size,
982 }
983 }
984
985 pub fn strict_along(axis: Axis, max: f32) -> Self {
986 match axis {
987 Axis::Horizontal => Self {
988 min: vec2f(max, 0.0),
989 max: vec2f(max, f32::INFINITY),
990 },
991 Axis::Vertical => Self {
992 min: vec2f(0.0, max),
993 max: vec2f(f32::INFINITY, max),
994 },
995 }
996 }
997
998 pub fn max_along(&self, axis: Axis) -> f32 {
999 match axis {
1000 Axis::Horizontal => self.max.x(),
1001 Axis::Vertical => self.max.y(),
1002 }
1003 }
1004
1005 pub fn min_along(&self, axis: Axis) -> f32 {
1006 match axis {
1007 Axis::Horizontal => self.min.x(),
1008 Axis::Vertical => self.min.y(),
1009 }
1010 }
1011
1012 pub fn constrain(&self, size: Vector2F) -> Vector2F {
1013 vec2f(
1014 size.x().min(self.max.x()).max(self.min.x()),
1015 size.y().min(self.max.y()).max(self.min.y()),
1016 )
1017 }
1018}
1019
1020impl Default for SizeConstraint {
1021 fn default() -> Self {
1022 SizeConstraint {
1023 min: Vector2F::zero(),
1024 max: Vector2F::splat(f32::INFINITY),
1025 }
1026 }
1027}
1028
1029impl ToJson for SizeConstraint {
1030 fn to_json(&self) -> serde_json::Value {
1031 json!({
1032 "min": self.min.to_json(),
1033 "max": self.max.to_json(),
1034 })
1035 }
1036}
1037
1038pub struct ChildView {
1039 view: AnyWeakViewHandle,
1040 view_name: &'static str,
1041}
1042
1043impl ChildView {
1044 pub fn new(view: impl Into<AnyViewHandle>, cx: &AppContext) -> Self {
1045 let view = view.into();
1046 let view_name = cx.view_ui_name(view.window_id(), view.id()).unwrap();
1047 Self {
1048 view: view.downgrade(),
1049 view_name,
1050 }
1051 }
1052}
1053
1054impl Element for ChildView {
1055 type LayoutState = bool;
1056 type PaintState = ();
1057
1058 fn layout(
1059 &mut self,
1060 constraint: SizeConstraint,
1061 cx: &mut LayoutContext,
1062 ) -> (Vector2F, Self::LayoutState) {
1063 if cx.rendered_views.contains_key(&self.view.id()) {
1064 let size = cx.layout(self.view.id(), constraint);
1065 (size, true)
1066 } else {
1067 log::error!(
1068 "layout called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1069 self.view.id(),
1070 self.view_name
1071 );
1072 (Vector2F::zero(), false)
1073 }
1074 }
1075
1076 fn paint(
1077 &mut self,
1078 bounds: RectF,
1079 visible_bounds: RectF,
1080 view_is_valid: &mut Self::LayoutState,
1081 cx: &mut PaintContext,
1082 ) {
1083 if *view_is_valid {
1084 cx.paint(self.view.id(), bounds.origin(), visible_bounds);
1085 } else {
1086 log::error!(
1087 "paint called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1088 self.view.id(),
1089 self.view_name
1090 );
1091 }
1092 }
1093
1094 fn rect_for_text_range(
1095 &self,
1096 range_utf16: Range<usize>,
1097 _: RectF,
1098 _: RectF,
1099 view_is_valid: &Self::LayoutState,
1100 _: &Self::PaintState,
1101 cx: &MeasurementContext,
1102 ) -> Option<RectF> {
1103 if *view_is_valid {
1104 cx.rect_for_text_range(self.view.id(), range_utf16)
1105 } else {
1106 log::error!(
1107 "rect_for_text_range called on a ChildView element whose underlying view was dropped (view_id: {}, name: {:?})",
1108 self.view.id(),
1109 self.view_name
1110 );
1111 None
1112 }
1113 }
1114
1115 fn debug(
1116 &self,
1117 bounds: RectF,
1118 _: &Self::LayoutState,
1119 _: &Self::PaintState,
1120 cx: &DebugContext,
1121 ) -> serde_json::Value {
1122 json!({
1123 "type": "ChildView",
1124 "view_id": self.view.id(),
1125 "bounds": bounds.to_json(),
1126 "view": if let Some(view) = self.view.upgrade(cx.app) {
1127 view.debug_json(cx.app)
1128 } else {
1129 json!(null)
1130 },
1131 "child": if let Some(view) = cx.rendered_views.get(&self.view.id()) {
1132 view.debug(cx)
1133 } else {
1134 json!(null)
1135 }
1136 })
1137 }
1138}