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