1//! Div is the central, reusable element that most GPUI trees will be built from.
2//! It functions as a container for other elements, and provides a number of
3//! useful features for laying out and styling its children as well as binding
4//! mouse events and action handlers. It is meant to be similar to the HTML `<div>`
5//! element, but for GPUI.
6//!
7//! # Build your own div
8//!
9//! GPUI does not directly provide APIs for stateful, multi step events like `click`
10//! and `drag`. We want GPUI users to be able to build their own abstractions for
11//! their own needs. However, as a UI framework, we're also obliged to provide some
12//! building blocks to make the process of building your own elements easier.
13//! For this we have the [`Interactivity`] and the [`StyleRefinement`] structs, as well
14//! as several associated traits. Together, these provide the full suite of Dom-like events
15//! and Tailwind-like styling that you can use to build your own custom elements. Div is
16//! constructed by combining these two systems into an all-in-one element.
17
18use crate::{
19 point, px, size, Action, AnyDrag, AnyElement, AnyTooltip, AnyView, App, Bounds, ClickEvent,
20 DispatchPhase, Element, ElementId, Entity, FocusHandle, Global, GlobalElementId, Hitbox,
21 HitboxId, IntoElement, IsZero, KeyContext, KeyDownEvent, KeyUpEvent, LayoutId,
22 ModifiersChangedEvent, MouseButton, MouseDownEvent, MouseMoveEvent, MouseUpEvent,
23 ParentElement, Pixels, Point, Render, ScrollWheelEvent, SharedString, Size, Style,
24 StyleRefinement, Styled, Task, TooltipId, Visibility, Window,
25};
26use collections::HashMap;
27use refineable::Refineable;
28use smallvec::SmallVec;
29use std::{
30 any::{Any, TypeId},
31 cell::RefCell,
32 cmp::Ordering,
33 fmt::Debug,
34 marker::PhantomData,
35 mem,
36 rc::Rc,
37 sync::Arc,
38 time::Duration,
39};
40use taffy::style::Overflow;
41use util::ResultExt;
42
43const DRAG_THRESHOLD: f64 = 2.;
44const TOOLTIP_SHOW_DELAY: Duration = Duration::from_millis(500);
45const HOVERABLE_TOOLTIP_HIDE_DELAY: Duration = Duration::from_millis(500);
46
47/// The styling information for a given group.
48pub struct GroupStyle {
49 /// The identifier for this group.
50 pub group: SharedString,
51
52 /// The specific style refinement that this group would apply
53 /// to its children.
54 pub style: Box<StyleRefinement>,
55}
56
57/// An event for when a drag is moving over this element, with the given state type.
58pub struct DragMoveEvent<T> {
59 /// The mouse move event that triggered this drag move event.
60 pub event: MouseMoveEvent,
61
62 /// The bounds of this element.
63 pub bounds: Bounds<Pixels>,
64 drag: PhantomData<T>,
65 dragged_item: Arc<dyn Any>,
66}
67
68impl<T: 'static> DragMoveEvent<T> {
69 /// Returns the drag state for this event.
70 pub fn drag<'b>(&self, cx: &'b App) -> &'b T {
71 cx.active_drag
72 .as_ref()
73 .and_then(|drag| drag.value.downcast_ref::<T>())
74 .expect("DragMoveEvent is only valid when the stored active drag is of the same type.")
75 }
76
77 /// An item that is about to be dropped.
78 pub fn dragged_item(&self) -> &dyn Any {
79 self.dragged_item.as_ref()
80 }
81}
82
83impl Interactivity {
84 /// Bind the given callback to the mouse down event for the given mouse button, during the bubble phase
85 /// The imperative API equivalent of [`InteractiveElement::on_mouse_down`]
86 ///
87 /// See [`Context::listener`](crate::Context::listener) to get access to the view state from this callback.
88 pub fn on_mouse_down(
89 &mut self,
90 button: MouseButton,
91 listener: impl Fn(&MouseDownEvent, &mut Window, &mut App) + 'static,
92 ) {
93 self.mouse_down_listeners
94 .push(Box::new(move |event, phase, hitbox, window, cx| {
95 if phase == DispatchPhase::Bubble
96 && event.button == button
97 && hitbox.is_hovered(window)
98 {
99 (listener)(event, window, cx)
100 }
101 }));
102 }
103
104 /// Bind the given callback to the mouse down event for any button, during the capture phase
105 /// The imperative API equivalent of [`InteractiveElement::capture_any_mouse_down`]
106 ///
107 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
108 pub fn capture_any_mouse_down(
109 &mut self,
110 listener: impl Fn(&MouseDownEvent, &mut Window, &mut App) + 'static,
111 ) {
112 self.mouse_down_listeners
113 .push(Box::new(move |event, phase, hitbox, window, cx| {
114 if phase == DispatchPhase::Capture && hitbox.is_hovered(window) {
115 (listener)(event, window, cx)
116 }
117 }));
118 }
119
120 /// Bind the given callback to the mouse down event for any button, during the bubble phase
121 /// the imperative API equivalent to [`InteractiveElement::on_any_mouse_down`]
122 ///
123 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
124 pub fn on_any_mouse_down(
125 &mut self,
126 listener: impl Fn(&MouseDownEvent, &mut Window, &mut App) + 'static,
127 ) {
128 self.mouse_down_listeners
129 .push(Box::new(move |event, phase, hitbox, window, cx| {
130 if phase == DispatchPhase::Bubble && hitbox.is_hovered(window) {
131 (listener)(event, window, cx)
132 }
133 }));
134 }
135
136 /// Bind the given callback to the mouse up event for the given button, during the bubble phase
137 /// the imperative API equivalent to [`InteractiveElement::on_mouse_up`]
138 ///
139 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
140 pub fn on_mouse_up(
141 &mut self,
142 button: MouseButton,
143 listener: impl Fn(&MouseUpEvent, &mut Window, &mut App) + 'static,
144 ) {
145 self.mouse_up_listeners
146 .push(Box::new(move |event, phase, hitbox, window, cx| {
147 if phase == DispatchPhase::Bubble
148 && event.button == button
149 && hitbox.is_hovered(window)
150 {
151 (listener)(event, window, cx)
152 }
153 }));
154 }
155
156 /// Bind the given callback to the mouse up event for any button, during the capture phase
157 /// the imperative API equivalent to [`InteractiveElement::capture_any_mouse_up`]
158 ///
159 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
160 pub fn capture_any_mouse_up(
161 &mut self,
162 listener: impl Fn(&MouseUpEvent, &mut Window, &mut App) + 'static,
163 ) {
164 self.mouse_up_listeners
165 .push(Box::new(move |event, phase, hitbox, window, cx| {
166 if phase == DispatchPhase::Capture && hitbox.is_hovered(window) {
167 (listener)(event, window, cx)
168 }
169 }));
170 }
171
172 /// Bind the given callback to the mouse up event for any button, during the bubble phase
173 /// the imperative API equivalent to [`Interactivity::on_any_mouse_up`]
174 ///
175 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
176 pub fn on_any_mouse_up(
177 &mut self,
178 listener: impl Fn(&MouseUpEvent, &mut Window, &mut App) + 'static,
179 ) {
180 self.mouse_up_listeners
181 .push(Box::new(move |event, phase, hitbox, window, cx| {
182 if phase == DispatchPhase::Bubble && hitbox.is_hovered(window) {
183 (listener)(event, window, cx)
184 }
185 }));
186 }
187
188 /// Bind the given callback to the mouse down event, on any button, during the capture phase,
189 /// when the mouse is outside of the bounds of this element.
190 /// The imperative API equivalent to [`InteractiveElement::on_mouse_down_out`]
191 ///
192 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
193 pub fn on_mouse_down_out(
194 &mut self,
195 listener: impl Fn(&MouseDownEvent, &mut Window, &mut App) + 'static,
196 ) {
197 self.mouse_down_listeners
198 .push(Box::new(move |event, phase, hitbox, window, cx| {
199 if phase == DispatchPhase::Capture && !hitbox.contains(&window.mouse_position()) {
200 (listener)(event, window, cx)
201 }
202 }));
203 }
204
205 /// Bind the given callback to the mouse up event, for the given button, during the capture phase,
206 /// when the mouse is outside of the bounds of this element.
207 /// The imperative API equivalent to [`InteractiveElement::on_mouse_up_out`]
208 ///
209 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
210 pub fn on_mouse_up_out(
211 &mut self,
212 button: MouseButton,
213 listener: impl Fn(&MouseUpEvent, &mut Window, &mut App) + 'static,
214 ) {
215 self.mouse_up_listeners
216 .push(Box::new(move |event, phase, hitbox, window, cx| {
217 if phase == DispatchPhase::Capture
218 && event.button == button
219 && !hitbox.is_hovered(window)
220 {
221 (listener)(event, window, cx);
222 }
223 }));
224 }
225
226 /// Bind the given callback to the mouse move event, during the bubble phase
227 /// The imperative API equivalent to [`InteractiveElement::on_mouse_move`]
228 ///
229 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
230 pub fn on_mouse_move(
231 &mut self,
232 listener: impl Fn(&MouseMoveEvent, &mut Window, &mut App) + 'static,
233 ) {
234 self.mouse_move_listeners
235 .push(Box::new(move |event, phase, hitbox, window, cx| {
236 if phase == DispatchPhase::Bubble && hitbox.is_hovered(window) {
237 (listener)(event, window, cx);
238 }
239 }));
240 }
241
242 /// Bind the given callback to the mouse drag event of the given type. Note that this
243 /// will be called for all move events, inside or outside of this element, as long as the
244 /// drag was started with this element under the mouse. Useful for implementing draggable
245 /// UIs that don't conform to a drag and drop style interaction, like resizing.
246 /// The imperative API equivalent to [`InteractiveElement::on_drag_move`]
247 ///
248 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
249 pub fn on_drag_move<T>(
250 &mut self,
251 listener: impl Fn(&DragMoveEvent<T>, &mut Window, &mut App) + 'static,
252 ) where
253 T: 'static,
254 {
255 self.mouse_move_listeners
256 .push(Box::new(move |event, phase, hitbox, window, cx| {
257 if phase == DispatchPhase::Capture {
258 if let Some(drag) = &cx.active_drag {
259 if drag.value.as_ref().type_id() == TypeId::of::<T>() {
260 (listener)(
261 &DragMoveEvent {
262 event: event.clone(),
263 bounds: hitbox.bounds,
264 drag: PhantomData,
265 dragged_item: Arc::clone(&drag.value),
266 },
267 window,
268 cx,
269 );
270 }
271 }
272 }
273 }));
274 }
275
276 /// Bind the given callback to scroll wheel events during the bubble phase
277 /// The imperative API equivalent to [`InteractiveElement::on_scroll_wheel`]
278 ///
279 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
280 pub fn on_scroll_wheel(
281 &mut self,
282 listener: impl Fn(&ScrollWheelEvent, &mut Window, &mut App) + 'static,
283 ) {
284 self.scroll_wheel_listeners
285 .push(Box::new(move |event, phase, hitbox, window, cx| {
286 if phase == DispatchPhase::Bubble && hitbox.is_hovered(window) {
287 (listener)(event, window, cx);
288 }
289 }));
290 }
291
292 /// Bind the given callback to an action dispatch during the capture phase
293 /// The imperative API equivalent to [`InteractiveElement::capture_action`]
294 ///
295 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
296 pub fn capture_action<A: Action>(
297 &mut self,
298 listener: impl Fn(&A, &mut Window, &mut App) + 'static,
299 ) {
300 self.action_listeners.push((
301 TypeId::of::<A>(),
302 Box::new(move |action, phase, window, cx| {
303 let action = action.downcast_ref().unwrap();
304 if phase == DispatchPhase::Capture {
305 (listener)(action, window, cx)
306 } else {
307 cx.propagate();
308 }
309 }),
310 ));
311 }
312
313 /// Bind the given callback to an action dispatch during the bubble phase
314 /// The imperative API equivalent to [`InteractiveElement::on_action`]
315 ///
316 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
317 pub fn on_action<A: Action>(&mut self, listener: impl Fn(&A, &mut Window, &mut App) + 'static) {
318 self.action_listeners.push((
319 TypeId::of::<A>(),
320 Box::new(move |action, phase, window, cx| {
321 let action = action.downcast_ref().unwrap();
322 if phase == DispatchPhase::Bubble {
323 (listener)(action, window, cx)
324 }
325 }),
326 ));
327 }
328
329 /// Bind the given callback to an action dispatch, based on a dynamic action parameter
330 /// instead of a type parameter. Useful for component libraries that want to expose
331 /// action bindings to their users.
332 /// The imperative API equivalent to [`InteractiveElement::on_boxed_action`]
333 ///
334 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
335 pub fn on_boxed_action(
336 &mut self,
337 action: &dyn Action,
338 listener: impl Fn(&dyn Action, &mut Window, &mut App) + 'static,
339 ) {
340 let action = action.boxed_clone();
341 self.action_listeners.push((
342 (*action).type_id(),
343 Box::new(move |_, phase, window, cx| {
344 if phase == DispatchPhase::Bubble {
345 (listener)(&*action, window, cx)
346 }
347 }),
348 ));
349 }
350
351 /// Bind the given callback to key down events during the bubble phase
352 /// The imperative API equivalent to [`InteractiveElement::on_key_down`]
353 ///
354 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
355 pub fn on_key_down(
356 &mut self,
357 listener: impl Fn(&KeyDownEvent, &mut Window, &mut App) + 'static,
358 ) {
359 self.key_down_listeners
360 .push(Box::new(move |event, phase, window, cx| {
361 if phase == DispatchPhase::Bubble {
362 (listener)(event, window, cx)
363 }
364 }));
365 }
366
367 /// Bind the given callback to key down events during the capture phase
368 /// The imperative API equivalent to [`InteractiveElement::capture_key_down`]
369 ///
370 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
371 pub fn capture_key_down(
372 &mut self,
373 listener: impl Fn(&KeyDownEvent, &mut Window, &mut App) + 'static,
374 ) {
375 self.key_down_listeners
376 .push(Box::new(move |event, phase, window, cx| {
377 if phase == DispatchPhase::Capture {
378 listener(event, window, cx)
379 }
380 }));
381 }
382
383 /// Bind the given callback to key up events during the bubble phase
384 /// The imperative API equivalent to [`InteractiveElement::on_key_up`]
385 ///
386 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
387 pub fn on_key_up(&mut self, listener: impl Fn(&KeyUpEvent, &mut Window, &mut App) + 'static) {
388 self.key_up_listeners
389 .push(Box::new(move |event, phase, window, cx| {
390 if phase == DispatchPhase::Bubble {
391 listener(event, window, cx)
392 }
393 }));
394 }
395
396 /// Bind the given callback to key up events during the capture phase
397 /// The imperative API equivalent to [`InteractiveElement::on_key_up`]
398 ///
399 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
400 pub fn capture_key_up(
401 &mut self,
402 listener: impl Fn(&KeyUpEvent, &mut Window, &mut App) + 'static,
403 ) {
404 self.key_up_listeners
405 .push(Box::new(move |event, phase, window, cx| {
406 if phase == DispatchPhase::Capture {
407 listener(event, window, cx)
408 }
409 }));
410 }
411
412 /// Bind the given callback to modifiers changing events.
413 /// The imperative API equivalent to [`InteractiveElement::on_modifiers_changed`]
414 ///
415 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
416 pub fn on_modifiers_changed(
417 &mut self,
418 listener: impl Fn(&ModifiersChangedEvent, &mut Window, &mut App) + 'static,
419 ) {
420 self.modifiers_changed_listeners
421 .push(Box::new(move |event, window, cx| {
422 listener(event, window, cx)
423 }));
424 }
425
426 /// Bind the given callback to drop events of the given type, whether or not the drag started on this element
427 /// The imperative API equivalent to [`InteractiveElement::on_drop`]
428 ///
429 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
430 pub fn on_drop<T: 'static>(&mut self, listener: impl Fn(&T, &mut Window, &mut App) + 'static) {
431 self.drop_listeners.push((
432 TypeId::of::<T>(),
433 Box::new(move |dragged_value, window, cx| {
434 listener(dragged_value.downcast_ref().unwrap(), window, cx);
435 }),
436 ));
437 }
438
439 /// Use the given predicate to determine whether or not a drop event should be dispatched to this element
440 /// The imperative API equivalent to [`InteractiveElement::can_drop`]
441 pub fn can_drop(
442 &mut self,
443 predicate: impl Fn(&dyn Any, &mut Window, &mut App) -> bool + 'static,
444 ) {
445 self.can_drop_predicate = Some(Box::new(predicate));
446 }
447
448 /// Bind the given callback to click events of this element
449 /// The imperative API equivalent to [`StatefulInteractiveElement::on_click`]
450 ///
451 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
452 pub fn on_click(&mut self, listener: impl Fn(&ClickEvent, &mut Window, &mut App) + 'static)
453 where
454 Self: Sized,
455 {
456 self.click_listeners
457 .push(Box::new(move |event, window, cx| {
458 listener(event, window, cx)
459 }));
460 }
461
462 /// On drag initiation, this callback will be used to create a new view to render the dragged value for a
463 /// drag and drop operation. This API should also be used as the equivalent of 'on drag start' with
464 /// the [`Self::on_drag_move`] API
465 /// The imperative API equivalent to [`StatefulInteractiveElement::on_drag`]
466 ///
467 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
468 pub fn on_drag<T, W>(
469 &mut self,
470 value: T,
471 constructor: impl Fn(&T, Point<Pixels>, &mut Window, &mut App) -> Entity<W> + 'static,
472 ) where
473 Self: Sized,
474 T: 'static,
475 W: 'static + Render,
476 {
477 debug_assert!(
478 self.drag_listener.is_none(),
479 "calling on_drag more than once on the same element is not supported"
480 );
481 self.drag_listener = Some((
482 Arc::new(value),
483 Box::new(move |value, offset, window, cx| {
484 constructor(value.downcast_ref().unwrap(), offset, window, cx).into()
485 }),
486 ));
487 }
488
489 /// Bind the given callback on the hover start and end events of this element. Note that the boolean
490 /// passed to the callback is true when the hover starts and false when it ends.
491 /// The imperative API equivalent to [`StatefulInteractiveElement::on_drag`]
492 ///
493 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
494 pub fn on_hover(&mut self, listener: impl Fn(&bool, &mut Window, &mut App) + 'static)
495 where
496 Self: Sized,
497 {
498 debug_assert!(
499 self.hover_listener.is_none(),
500 "calling on_hover more than once on the same element is not supported"
501 );
502 self.hover_listener = Some(Box::new(listener));
503 }
504
505 /// Use the given callback to construct a new tooltip view when the mouse hovers over this element.
506 /// The imperative API equivalent to [`InteractiveElement::tooltip`]
507 pub fn tooltip(&mut self, build_tooltip: impl Fn(&mut Window, &mut App) -> AnyView + 'static)
508 where
509 Self: Sized,
510 {
511 debug_assert!(
512 self.tooltip_builder.is_none(),
513 "calling tooltip more than once on the same element is not supported"
514 );
515 self.tooltip_builder = Some(TooltipBuilder {
516 build: Rc::new(build_tooltip),
517 hoverable: false,
518 });
519 }
520
521 /// Use the given callback to construct a new tooltip view when the mouse hovers over this element.
522 /// The tooltip itself is also hoverable and won't disappear when the user moves the mouse into
523 /// the tooltip. The imperative API equivalent to [`InteractiveElement::hoverable_tooltip`]
524 pub fn hoverable_tooltip(
525 &mut self,
526 build_tooltip: impl Fn(&mut Window, &mut App) -> AnyView + 'static,
527 ) where
528 Self: Sized,
529 {
530 debug_assert!(
531 self.tooltip_builder.is_none(),
532 "calling tooltip more than once on the same element is not supported"
533 );
534 self.tooltip_builder = Some(TooltipBuilder {
535 build: Rc::new(build_tooltip),
536 hoverable: true,
537 });
538 }
539
540 /// Block the mouse from interacting with this element or any of its children
541 /// The imperative API equivalent to [`InteractiveElement::occlude`]
542 pub fn occlude_mouse(&mut self) {
543 self.occlude_mouse = true;
544 }
545}
546
547/// A trait for elements that want to use the standard GPUI event handlers that don't
548/// require any state.
549pub trait InteractiveElement: Sized {
550 /// Retrieve the interactivity state associated with this element
551 fn interactivity(&mut self) -> &mut Interactivity;
552
553 /// Assign this element to a group of elements that can be styled together
554 fn group(mut self, group: impl Into<SharedString>) -> Self {
555 self.interactivity().group = Some(group.into());
556 self
557 }
558
559 /// Assign this element an ID, so that it can be used with interactivity
560 fn id(mut self, id: impl Into<ElementId>) -> Stateful<Self> {
561 self.interactivity().element_id = Some(id.into());
562
563 Stateful { element: self }
564 }
565
566 /// Track the focus state of the given focus handle on this element.
567 /// If the focus handle is focused by the application, this element will
568 /// apply its focused styles.
569 fn track_focus(mut self, focus_handle: &FocusHandle) -> FocusableWrapper<Self> {
570 self.interactivity().focusable = true;
571 self.interactivity().tracked_focus_handle = Some(focus_handle.clone());
572 FocusableWrapper { element: self }
573 }
574
575 /// Set the keymap context for this element. This will be used to determine
576 /// which action to dispatch from the keymap.
577 fn key_context<C, E>(mut self, key_context: C) -> Self
578 where
579 C: TryInto<KeyContext, Error = E>,
580 E: Debug,
581 {
582 if let Some(key_context) = key_context.try_into().log_err() {
583 self.interactivity().key_context = Some(key_context);
584 }
585 self
586 }
587
588 /// Apply the given style to this element when the mouse hovers over it
589 fn hover(mut self, f: impl FnOnce(StyleRefinement) -> StyleRefinement) -> Self {
590 debug_assert!(
591 self.interactivity().hover_style.is_none(),
592 "hover style already set"
593 );
594 self.interactivity().hover_style = Some(Box::new(f(StyleRefinement::default())));
595 self
596 }
597
598 /// Apply the given style to this element when the mouse hovers over a group member
599 fn group_hover(
600 mut self,
601 group_name: impl Into<SharedString>,
602 f: impl FnOnce(StyleRefinement) -> StyleRefinement,
603 ) -> Self {
604 self.interactivity().group_hover_style = Some(GroupStyle {
605 group: group_name.into(),
606 style: Box::new(f(StyleRefinement::default())),
607 });
608 self
609 }
610
611 /// Bind the given callback to the mouse down event for the given mouse button,
612 /// the fluent API equivalent to [`Interactivity::on_mouse_down`]
613 ///
614 /// See [`Context::listener`](crate::Context::listener) to get access to the view state from this callback.
615 fn on_mouse_down(
616 mut self,
617 button: MouseButton,
618 listener: impl Fn(&MouseDownEvent, &mut Window, &mut App) + 'static,
619 ) -> Self {
620 self.interactivity().on_mouse_down(button, listener);
621 self
622 }
623
624 #[cfg(any(test, feature = "test-support"))]
625 /// Set a key that can be used to look up this element's bounds
626 /// in the [`VisualTestContext::debug_bounds`] map
627 /// This is a noop in release builds
628 fn debug_selector(mut self, f: impl FnOnce() -> String) -> Self {
629 self.interactivity().debug_selector = Some(f());
630 self
631 }
632
633 #[cfg(not(any(test, feature = "test-support")))]
634 /// Set a key that can be used to look up this element's bounds
635 /// in the [`VisualTestContext::debug_bounds`] map
636 /// This is a noop in release builds
637 #[inline]
638 fn debug_selector(self, _: impl FnOnce() -> String) -> Self {
639 self
640 }
641
642 /// Bind the given callback to the mouse down event for any button, during the capture phase
643 /// the fluent API equivalent to [`Interactivity::capture_any_mouse_down`]
644 ///
645 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
646 fn capture_any_mouse_down(
647 mut self,
648 listener: impl Fn(&MouseDownEvent, &mut Window, &mut App) + 'static,
649 ) -> Self {
650 self.interactivity().capture_any_mouse_down(listener);
651 self
652 }
653
654 /// Bind the given callback to the mouse down event for any button, during the capture phase
655 /// the fluent API equivalent to [`Interactivity::on_any_mouse_down`]
656 ///
657 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
658 fn on_any_mouse_down(
659 mut self,
660 listener: impl Fn(&MouseDownEvent, &mut Window, &mut App) + 'static,
661 ) -> Self {
662 self.interactivity().on_any_mouse_down(listener);
663 self
664 }
665
666 /// Bind the given callback to the mouse up event for the given button, during the bubble phase
667 /// the fluent API equivalent to [`Interactivity::on_mouse_up`]
668 ///
669 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
670 fn on_mouse_up(
671 mut self,
672 button: MouseButton,
673 listener: impl Fn(&MouseUpEvent, &mut Window, &mut App) + 'static,
674 ) -> Self {
675 self.interactivity().on_mouse_up(button, listener);
676 self
677 }
678
679 /// Bind the given callback to the mouse up event for any button, during the capture phase
680 /// the fluent API equivalent to [`Interactivity::capture_any_mouse_up`]
681 ///
682 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
683 fn capture_any_mouse_up(
684 mut self,
685 listener: impl Fn(&MouseUpEvent, &mut Window, &mut App) + 'static,
686 ) -> Self {
687 self.interactivity().capture_any_mouse_up(listener);
688 self
689 }
690
691 /// Bind the given callback to the mouse down event, on any button, during the capture phase,
692 /// when the mouse is outside of the bounds of this element.
693 /// The fluent API equivalent to [`Interactivity::on_mouse_down_out`]
694 ///
695 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
696 fn on_mouse_down_out(
697 mut self,
698 listener: impl Fn(&MouseDownEvent, &mut Window, &mut App) + 'static,
699 ) -> Self {
700 self.interactivity().on_mouse_down_out(listener);
701 self
702 }
703
704 /// Bind the given callback to the mouse up event, for the given button, during the capture phase,
705 /// when the mouse is outside of the bounds of this element.
706 /// The fluent API equivalent to [`Interactivity::on_mouse_up_out`]
707 ///
708 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
709 fn on_mouse_up_out(
710 mut self,
711 button: MouseButton,
712 listener: impl Fn(&MouseUpEvent, &mut Window, &mut App) + 'static,
713 ) -> Self {
714 self.interactivity().on_mouse_up_out(button, listener);
715 self
716 }
717
718 /// Bind the given callback to the mouse move event, during the bubble phase
719 /// The fluent API equivalent to [`Interactivity::on_mouse_move`]
720 ///
721 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
722 fn on_mouse_move(
723 mut self,
724 listener: impl Fn(&MouseMoveEvent, &mut Window, &mut App) + 'static,
725 ) -> Self {
726 self.interactivity().on_mouse_move(listener);
727 self
728 }
729
730 /// Bind the given callback to the mouse drag event of the given type. Note that this
731 /// will be called for all move events, inside or outside of this element, as long as the
732 /// drag was started with this element under the mouse. Useful for implementing draggable
733 /// UIs that don't conform to a drag and drop style interaction, like resizing.
734 /// The fluent API equivalent to [`Interactivity::on_drag_move`]
735 ///
736 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
737 fn on_drag_move<T: 'static>(
738 mut self,
739 listener: impl Fn(&DragMoveEvent<T>, &mut Window, &mut App) + 'static,
740 ) -> Self {
741 self.interactivity().on_drag_move(listener);
742 self
743 }
744
745 /// Bind the given callback to scroll wheel events during the bubble phase
746 /// The fluent API equivalent to [`Interactivity::on_scroll_wheel`]
747 ///
748 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
749 fn on_scroll_wheel(
750 mut self,
751 listener: impl Fn(&ScrollWheelEvent, &mut Window, &mut App) + 'static,
752 ) -> Self {
753 self.interactivity().on_scroll_wheel(listener);
754 self
755 }
756
757 /// Capture the given action, before normal action dispatch can fire
758 /// The fluent API equivalent to [`Interactivity::on_scroll_wheel`]
759 ///
760 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
761 fn capture_action<A: Action>(
762 mut self,
763 listener: impl Fn(&A, &mut Window, &mut App) + 'static,
764 ) -> Self {
765 self.interactivity().capture_action(listener);
766 self
767 }
768
769 /// Bind the given callback to an action dispatch during the bubble phase
770 /// The fluent API equivalent to [`Interactivity::on_action`]
771 ///
772 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
773 fn on_action<A: Action>(
774 mut self,
775 listener: impl Fn(&A, &mut Window, &mut App) + 'static,
776 ) -> Self {
777 self.interactivity().on_action(listener);
778 self
779 }
780
781 /// Bind the given callback to an action dispatch, based on a dynamic action parameter
782 /// instead of a type parameter. Useful for component libraries that want to expose
783 /// action bindings to their users.
784 /// The fluent API equivalent to [`Interactivity::on_boxed_action`]
785 ///
786 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
787 fn on_boxed_action(
788 mut self,
789 action: &dyn Action,
790 listener: impl Fn(&dyn Action, &mut Window, &mut App) + 'static,
791 ) -> Self {
792 self.interactivity().on_boxed_action(action, listener);
793 self
794 }
795
796 /// Bind the given callback to key down events during the bubble phase
797 /// The fluent API equivalent to [`Interactivity::on_key_down`]
798 ///
799 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
800 fn on_key_down(
801 mut self,
802 listener: impl Fn(&KeyDownEvent, &mut Window, &mut App) + 'static,
803 ) -> Self {
804 self.interactivity().on_key_down(listener);
805 self
806 }
807
808 /// Bind the given callback to key down events during the capture phase
809 /// The fluent API equivalent to [`Interactivity::capture_key_down`]
810 ///
811 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
812 fn capture_key_down(
813 mut self,
814 listener: impl Fn(&KeyDownEvent, &mut Window, &mut App) + 'static,
815 ) -> Self {
816 self.interactivity().capture_key_down(listener);
817 self
818 }
819
820 /// Bind the given callback to key up events during the bubble phase
821 /// The fluent API equivalent to [`Interactivity::on_key_up`]
822 ///
823 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
824 fn on_key_up(
825 mut self,
826 listener: impl Fn(&KeyUpEvent, &mut Window, &mut App) + 'static,
827 ) -> Self {
828 self.interactivity().on_key_up(listener);
829 self
830 }
831
832 /// Bind the given callback to key up events during the capture phase
833 /// The fluent API equivalent to [`Interactivity::capture_key_up`]
834 ///
835 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
836 fn capture_key_up(
837 mut self,
838 listener: impl Fn(&KeyUpEvent, &mut Window, &mut App) + 'static,
839 ) -> Self {
840 self.interactivity().capture_key_up(listener);
841 self
842 }
843
844 /// Bind the given callback to modifiers changing events.
845 /// The fluent API equivalent to [`Interactivity::on_modifiers_changed`]
846 ///
847 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
848 fn on_modifiers_changed(
849 mut self,
850 listener: impl Fn(&ModifiersChangedEvent, &mut Window, &mut App) + 'static,
851 ) -> Self {
852 self.interactivity().on_modifiers_changed(listener);
853 self
854 }
855
856 /// Apply the given style when the given data type is dragged over this element
857 fn drag_over<S: 'static>(
858 mut self,
859 f: impl 'static + Fn(StyleRefinement, &S, &Window, &App) -> StyleRefinement,
860 ) -> Self {
861 self.interactivity().drag_over_styles.push((
862 TypeId::of::<S>(),
863 Box::new(move |currently_dragged: &dyn Any, window, cx| {
864 f(
865 StyleRefinement::default(),
866 currently_dragged.downcast_ref::<S>().unwrap(),
867 window,
868 cx,
869 )
870 }),
871 ));
872 self
873 }
874
875 /// Apply the given style when the given data type is dragged over this element's group
876 fn group_drag_over<S: 'static>(
877 mut self,
878 group_name: impl Into<SharedString>,
879 f: impl FnOnce(StyleRefinement) -> StyleRefinement,
880 ) -> Self {
881 self.interactivity().group_drag_over_styles.push((
882 TypeId::of::<S>(),
883 GroupStyle {
884 group: group_name.into(),
885 style: Box::new(f(StyleRefinement::default())),
886 },
887 ));
888 self
889 }
890
891 /// Bind the given callback to drop events of the given type, whether or not the drag started on this element
892 /// The fluent API equivalent to [`Interactivity::on_drop`]
893 ///
894 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
895 fn on_drop<T: 'static>(
896 mut self,
897 listener: impl Fn(&T, &mut Window, &mut App) + 'static,
898 ) -> Self {
899 self.interactivity().on_drop(listener);
900 self
901 }
902
903 /// Use the given predicate to determine whether or not a drop event should be dispatched to this element
904 /// The fluent API equivalent to [`Interactivity::can_drop`]
905 fn can_drop(
906 mut self,
907 predicate: impl Fn(&dyn Any, &mut Window, &mut App) -> bool + 'static,
908 ) -> Self {
909 self.interactivity().can_drop(predicate);
910 self
911 }
912
913 /// Block the mouse from interacting with this element or any of its children
914 /// The fluent API equivalent to [`Interactivity::occlude_mouse`]
915 fn occlude(mut self) -> Self {
916 self.interactivity().occlude_mouse();
917 self
918 }
919
920 /// Block the mouse from interacting with this element or any of its children
921 /// The fluent API equivalent to [`Interactivity::occlude_mouse`]
922 fn block_mouse_down(mut self) -> Self {
923 self.on_mouse_down(MouseButton::Left, |_, _, cx| cx.stop_propagation())
924 }
925}
926
927/// A trait for elements that want to use the standard GPUI interactivity features
928/// that require state.
929pub trait StatefulInteractiveElement: InteractiveElement {
930 /// Set this element to focusable.
931 fn focusable(mut self) -> FocusableWrapper<Self> {
932 self.interactivity().focusable = true;
933 FocusableWrapper { element: self }
934 }
935
936 /// Set the overflow x and y to scroll.
937 fn overflow_scroll(mut self) -> Self {
938 self.interactivity().base_style.overflow.x = Some(Overflow::Scroll);
939 self.interactivity().base_style.overflow.y = Some(Overflow::Scroll);
940 self
941 }
942
943 /// Set the overflow x to scroll.
944 fn overflow_x_scroll(mut self) -> Self {
945 self.interactivity().base_style.overflow.x = Some(Overflow::Scroll);
946 self
947 }
948
949 /// Set the overflow y to scroll.
950 fn overflow_y_scroll(mut self) -> Self {
951 self.interactivity().base_style.overflow.y = Some(Overflow::Scroll);
952 self
953 }
954
955 /// Track the scroll state of this element with the given handle.
956 fn track_scroll(mut self, scroll_handle: &ScrollHandle) -> Self {
957 self.interactivity().tracked_scroll_handle = Some(scroll_handle.clone());
958 self
959 }
960
961 /// Track the scroll state of this element with the given handle.
962 fn anchor_scroll(mut self, scroll_anchor: Option<ScrollAnchor>) -> Self {
963 self.interactivity().scroll_anchor = scroll_anchor;
964 self
965 }
966
967 /// Set the given styles to be applied when this element is active.
968 fn active(mut self, f: impl FnOnce(StyleRefinement) -> StyleRefinement) -> Self
969 where
970 Self: Sized,
971 {
972 self.interactivity().active_style = Some(Box::new(f(StyleRefinement::default())));
973 self
974 }
975
976 /// Set the given styles to be applied when this element's group is active.
977 fn group_active(
978 mut self,
979 group_name: impl Into<SharedString>,
980 f: impl FnOnce(StyleRefinement) -> StyleRefinement,
981 ) -> Self
982 where
983 Self: Sized,
984 {
985 self.interactivity().group_active_style = Some(GroupStyle {
986 group: group_name.into(),
987 style: Box::new(f(StyleRefinement::default())),
988 });
989 self
990 }
991
992 /// Bind the given callback to click events of this element
993 /// The fluent API equivalent to [`Interactivity::on_click`]
994 ///
995 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
996 fn on_click(mut self, listener: impl Fn(&ClickEvent, &mut Window, &mut App) + 'static) -> Self
997 where
998 Self: Sized,
999 {
1000 self.interactivity().on_click(listener);
1001 self
1002 }
1003
1004 /// On drag initiation, this callback will be used to create a new view to render the dragged value for a
1005 /// drag and drop operation. This API should also be used as the equivalent of 'on drag start' with
1006 /// the [`Self::on_drag_move`] API.
1007 /// The callback also has access to the offset of triggering click from the origin of parent element.
1008 /// The fluent API equivalent to [`Interactivity::on_drag`]
1009 ///
1010 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
1011 fn on_drag<T, W>(
1012 mut self,
1013 value: T,
1014 constructor: impl Fn(&T, Point<Pixels>, &mut Window, &mut App) -> Entity<W> + 'static,
1015 ) -> Self
1016 where
1017 Self: Sized,
1018 T: 'static,
1019 W: 'static + Render,
1020 {
1021 self.interactivity().on_drag(value, constructor);
1022 self
1023 }
1024
1025 /// Bind the given callback on the hover start and end events of this element. Note that the boolean
1026 /// passed to the callback is true when the hover starts and false when it ends.
1027 /// The fluent API equivalent to [`Interactivity::on_hover`]
1028 ///
1029 /// See [`Context::listener`](crate::Context::listener) to get access to a view's state from this callback.
1030 fn on_hover(mut self, listener: impl Fn(&bool, &mut Window, &mut App) + 'static) -> Self
1031 where
1032 Self: Sized,
1033 {
1034 self.interactivity().on_hover(listener);
1035 self
1036 }
1037
1038 /// Use the given callback to construct a new tooltip view when the mouse hovers over this element.
1039 /// The fluent API equivalent to [`Interactivity::tooltip`]
1040 fn tooltip(mut self, build_tooltip: impl Fn(&mut Window, &mut App) -> AnyView + 'static) -> Self
1041 where
1042 Self: Sized,
1043 {
1044 self.interactivity().tooltip(build_tooltip);
1045 self
1046 }
1047
1048 /// Use the given callback to construct a new tooltip view when the mouse hovers over this element.
1049 /// The tooltip itself is also hoverable and won't disappear when the user moves the mouse into
1050 /// the tooltip. The fluent API equivalent to [`Interactivity::hoverable_tooltip`]
1051 fn hoverable_tooltip(
1052 mut self,
1053 build_tooltip: impl Fn(&mut Window, &mut App) -> AnyView + 'static,
1054 ) -> Self
1055 where
1056 Self: Sized,
1057 {
1058 self.interactivity().hoverable_tooltip(build_tooltip);
1059 self
1060 }
1061}
1062
1063/// A trait for providing focus related APIs to interactive elements
1064pub trait FocusableElement: InteractiveElement {
1065 /// Set the given styles to be applied when this element, specifically, is focused.
1066 fn focus(mut self, f: impl FnOnce(StyleRefinement) -> StyleRefinement) -> Self
1067 where
1068 Self: Sized,
1069 {
1070 self.interactivity().focus_style = Some(Box::new(f(StyleRefinement::default())));
1071 self
1072 }
1073
1074 /// Set the given styles to be applied when this element is inside another element that is focused.
1075 fn in_focus(mut self, f: impl FnOnce(StyleRefinement) -> StyleRefinement) -> Self
1076 where
1077 Self: Sized,
1078 {
1079 self.interactivity().in_focus_style = Some(Box::new(f(StyleRefinement::default())));
1080 self
1081 }
1082}
1083
1084pub(crate) type MouseDownListener =
1085 Box<dyn Fn(&MouseDownEvent, DispatchPhase, &Hitbox, &mut Window, &mut App) + 'static>;
1086pub(crate) type MouseUpListener =
1087 Box<dyn Fn(&MouseUpEvent, DispatchPhase, &Hitbox, &mut Window, &mut App) + 'static>;
1088
1089pub(crate) type MouseMoveListener =
1090 Box<dyn Fn(&MouseMoveEvent, DispatchPhase, &Hitbox, &mut Window, &mut App) + 'static>;
1091
1092pub(crate) type ScrollWheelListener =
1093 Box<dyn Fn(&ScrollWheelEvent, DispatchPhase, &Hitbox, &mut Window, &mut App) + 'static>;
1094
1095pub(crate) type ClickListener = Box<dyn Fn(&ClickEvent, &mut Window, &mut App) + 'static>;
1096
1097pub(crate) type DragListener =
1098 Box<dyn Fn(&dyn Any, Point<Pixels>, &mut Window, &mut App) -> AnyView + 'static>;
1099
1100type DropListener = Box<dyn Fn(&dyn Any, &mut Window, &mut App) + 'static>;
1101
1102type CanDropPredicate = Box<dyn Fn(&dyn Any, &mut Window, &mut App) -> bool + 'static>;
1103
1104pub(crate) struct TooltipBuilder {
1105 build: Rc<dyn Fn(&mut Window, &mut App) -> AnyView + 'static>,
1106 hoverable: bool,
1107}
1108
1109pub(crate) type KeyDownListener =
1110 Box<dyn Fn(&KeyDownEvent, DispatchPhase, &mut Window, &mut App) + 'static>;
1111
1112pub(crate) type KeyUpListener =
1113 Box<dyn Fn(&KeyUpEvent, DispatchPhase, &mut Window, &mut App) + 'static>;
1114
1115pub(crate) type ModifiersChangedListener =
1116 Box<dyn Fn(&ModifiersChangedEvent, &mut Window, &mut App) + 'static>;
1117
1118pub(crate) type ActionListener =
1119 Box<dyn Fn(&dyn Any, DispatchPhase, &mut Window, &mut App) + 'static>;
1120
1121/// Construct a new [`Div`] element
1122#[track_caller]
1123pub fn div() -> Div {
1124 #[cfg(debug_assertions)]
1125 let interactivity = Interactivity {
1126 location: Some(*core::panic::Location::caller()),
1127 ..Default::default()
1128 };
1129
1130 #[cfg(not(debug_assertions))]
1131 let interactivity = Interactivity::default();
1132
1133 Div {
1134 interactivity,
1135 children: SmallVec::default(),
1136 prepaint_listener: None,
1137 }
1138}
1139
1140/// A [`Div`] element, the all-in-one element for building complex UIs in GPUI
1141pub struct Div {
1142 interactivity: Interactivity,
1143 children: SmallVec<[AnyElement; 2]>,
1144 prepaint_listener: Option<Box<dyn Fn(Vec<Bounds<Pixels>>, &mut Window, &mut App) + 'static>>,
1145}
1146
1147impl Div {
1148 /// Add a listener to be called when the children of this `Div` are prepainted.
1149 /// This allows you to store the [`Bounds`] of the children for later use.
1150 pub fn on_children_prepainted(
1151 mut self,
1152 listener: impl Fn(Vec<Bounds<Pixels>>, &mut Window, &mut App) + 'static,
1153 ) -> Self {
1154 self.prepaint_listener = Some(Box::new(listener));
1155 self
1156 }
1157}
1158
1159/// A frame state for a `Div` element, which contains layout IDs for its children.
1160///
1161/// This struct is used internally by the `Div` element to manage the layout state of its children
1162/// during the UI update cycle. It holds a small vector of `LayoutId` values, each corresponding to
1163/// a child element of the `Div`. These IDs are used to query the layout engine for the computed
1164/// bounds of the children after the layout phase is complete.
1165pub struct DivFrameState {
1166 child_layout_ids: SmallVec<[LayoutId; 2]>,
1167}
1168
1169impl Styled for Div {
1170 fn style(&mut self) -> &mut StyleRefinement {
1171 &mut self.interactivity.base_style
1172 }
1173}
1174
1175impl InteractiveElement for Div {
1176 fn interactivity(&mut self) -> &mut Interactivity {
1177 &mut self.interactivity
1178 }
1179}
1180
1181impl ParentElement for Div {
1182 fn extend(&mut self, elements: impl IntoIterator<Item = AnyElement>) {
1183 self.children.extend(elements)
1184 }
1185}
1186
1187impl Element for Div {
1188 type RequestLayoutState = DivFrameState;
1189 type PrepaintState = Option<Hitbox>;
1190
1191 fn id(&self) -> Option<ElementId> {
1192 self.interactivity.element_id.clone()
1193 }
1194
1195 fn request_layout(
1196 &mut self,
1197 global_id: Option<&GlobalElementId>,
1198 window: &mut Window,
1199 cx: &mut App,
1200 ) -> (LayoutId, Self::RequestLayoutState) {
1201 let mut child_layout_ids = SmallVec::new();
1202 let layout_id =
1203 self.interactivity
1204 .request_layout(global_id, window, cx, |style, window, cx| {
1205 window.with_text_style(style.text_style().cloned(), |window| {
1206 child_layout_ids = self
1207 .children
1208 .iter_mut()
1209 .map(|child| child.request_layout(window, cx))
1210 .collect::<SmallVec<_>>();
1211 window.request_layout(style, child_layout_ids.iter().copied(), cx)
1212 })
1213 });
1214 (layout_id, DivFrameState { child_layout_ids })
1215 }
1216
1217 fn prepaint(
1218 &mut self,
1219 global_id: Option<&GlobalElementId>,
1220 bounds: Bounds<Pixels>,
1221 request_layout: &mut Self::RequestLayoutState,
1222 window: &mut Window,
1223 cx: &mut App,
1224 ) -> Option<Hitbox> {
1225 let has_prepaint_listener = self.prepaint_listener.is_some();
1226 let mut children_bounds = Vec::with_capacity(if has_prepaint_listener {
1227 request_layout.child_layout_ids.len()
1228 } else {
1229 0
1230 });
1231
1232 let mut child_min = point(Pixels::MAX, Pixels::MAX);
1233 let mut child_max = Point::default();
1234 if let Some(handle) = self.interactivity.scroll_anchor.as_ref() {
1235 *handle.last_origin.borrow_mut() = bounds.origin - window.element_offset();
1236 }
1237 let content_size = if request_layout.child_layout_ids.is_empty() {
1238 bounds.size
1239 } else if let Some(scroll_handle) = self.interactivity.tracked_scroll_handle.as_ref() {
1240 let mut state = scroll_handle.0.borrow_mut();
1241 state.child_bounds = Vec::with_capacity(request_layout.child_layout_ids.len());
1242 state.bounds = bounds;
1243 for child_layout_id in &request_layout.child_layout_ids {
1244 let child_bounds = window.layout_bounds(*child_layout_id);
1245 child_min = child_min.min(&child_bounds.origin);
1246 child_max = child_max.max(&child_bounds.bottom_right());
1247 state.child_bounds.push(child_bounds);
1248 }
1249 (child_max - child_min).into()
1250 } else {
1251 for child_layout_id in &request_layout.child_layout_ids {
1252 let child_bounds = window.layout_bounds(*child_layout_id);
1253 child_min = child_min.min(&child_bounds.origin);
1254 child_max = child_max.max(&child_bounds.bottom_right());
1255
1256 if has_prepaint_listener {
1257 children_bounds.push(child_bounds);
1258 }
1259 }
1260 (child_max - child_min).into()
1261 };
1262
1263 self.interactivity.prepaint(
1264 global_id,
1265 bounds,
1266 content_size,
1267 window,
1268 cx,
1269 |_style, scroll_offset, hitbox, window, cx| {
1270 window.with_element_offset(scroll_offset, |window| {
1271 for child in &mut self.children {
1272 child.prepaint(window, cx);
1273 }
1274 });
1275
1276 if let Some(listener) = self.prepaint_listener.as_ref() {
1277 listener(children_bounds, window, cx);
1278 }
1279
1280 hitbox
1281 },
1282 )
1283 }
1284
1285 fn paint(
1286 &mut self,
1287 global_id: Option<&GlobalElementId>,
1288 bounds: Bounds<Pixels>,
1289 _request_layout: &mut Self::RequestLayoutState,
1290 hitbox: &mut Option<Hitbox>,
1291 window: &mut Window,
1292 cx: &mut App,
1293 ) {
1294 self.interactivity.paint(
1295 global_id,
1296 bounds,
1297 hitbox.as_ref(),
1298 window,
1299 cx,
1300 |_style, window, cx| {
1301 for child in &mut self.children {
1302 child.paint(window, cx);
1303 }
1304 },
1305 );
1306 }
1307}
1308
1309impl IntoElement for Div {
1310 type Element = Self;
1311
1312 fn into_element(self) -> Self::Element {
1313 self
1314 }
1315}
1316
1317/// The interactivity struct. Powers all of the general-purpose
1318/// interactivity in the `Div` element.
1319#[derive(Default)]
1320pub struct Interactivity {
1321 /// The element ID of the element. In id is required to support a stateful subset of the interactivity such as on_click.
1322 pub element_id: Option<ElementId>,
1323 /// Whether the element was clicked. This will only be present after layout.
1324 pub active: Option<bool>,
1325 /// Whether the element was hovered. This will only be present after paint if an hitbox
1326 /// was created for the interactive element.
1327 pub hovered: Option<bool>,
1328 pub(crate) tooltip_id: Option<TooltipId>,
1329 pub(crate) content_size: Size<Pixels>,
1330 pub(crate) key_context: Option<KeyContext>,
1331 pub(crate) focusable: bool,
1332 pub(crate) tracked_focus_handle: Option<FocusHandle>,
1333 pub(crate) tracked_scroll_handle: Option<ScrollHandle>,
1334 pub(crate) scroll_anchor: Option<ScrollAnchor>,
1335 pub(crate) scroll_offset: Option<Rc<RefCell<Point<Pixels>>>>,
1336 pub(crate) group: Option<SharedString>,
1337 /// The base style of the element, before any modifications are applied
1338 /// by focus, active, etc.
1339 pub base_style: Box<StyleRefinement>,
1340 pub(crate) focus_style: Option<Box<StyleRefinement>>,
1341 pub(crate) in_focus_style: Option<Box<StyleRefinement>>,
1342 pub(crate) hover_style: Option<Box<StyleRefinement>>,
1343 pub(crate) group_hover_style: Option<GroupStyle>,
1344 pub(crate) active_style: Option<Box<StyleRefinement>>,
1345 pub(crate) group_active_style: Option<GroupStyle>,
1346 pub(crate) drag_over_styles: Vec<(
1347 TypeId,
1348 Box<dyn Fn(&dyn Any, &mut Window, &mut App) -> StyleRefinement>,
1349 )>,
1350 pub(crate) group_drag_over_styles: Vec<(TypeId, GroupStyle)>,
1351 pub(crate) mouse_down_listeners: Vec<MouseDownListener>,
1352 pub(crate) mouse_up_listeners: Vec<MouseUpListener>,
1353 pub(crate) mouse_move_listeners: Vec<MouseMoveListener>,
1354 pub(crate) scroll_wheel_listeners: Vec<ScrollWheelListener>,
1355 pub(crate) key_down_listeners: Vec<KeyDownListener>,
1356 pub(crate) key_up_listeners: Vec<KeyUpListener>,
1357 pub(crate) modifiers_changed_listeners: Vec<ModifiersChangedListener>,
1358 pub(crate) action_listeners: Vec<(TypeId, ActionListener)>,
1359 pub(crate) drop_listeners: Vec<(TypeId, DropListener)>,
1360 pub(crate) can_drop_predicate: Option<CanDropPredicate>,
1361 pub(crate) click_listeners: Vec<ClickListener>,
1362 pub(crate) drag_listener: Option<(Arc<dyn Any>, DragListener)>,
1363 pub(crate) hover_listener: Option<Box<dyn Fn(&bool, &mut Window, &mut App)>>,
1364 pub(crate) tooltip_builder: Option<TooltipBuilder>,
1365 pub(crate) occlude_mouse: bool,
1366
1367 #[cfg(debug_assertions)]
1368 pub(crate) location: Option<core::panic::Location<'static>>,
1369
1370 #[cfg(any(test, feature = "test-support"))]
1371 pub(crate) debug_selector: Option<String>,
1372}
1373
1374impl Interactivity {
1375 /// Layout this element according to this interactivity state's configured styles
1376 pub fn request_layout(
1377 &mut self,
1378 global_id: Option<&GlobalElementId>,
1379 window: &mut Window,
1380 cx: &mut App,
1381 f: impl FnOnce(Style, &mut Window, &mut App) -> LayoutId,
1382 ) -> LayoutId {
1383 window.with_optional_element_state::<InteractiveElementState, _>(
1384 global_id,
1385 |element_state, window| {
1386 let mut element_state =
1387 element_state.map(|element_state| element_state.unwrap_or_default());
1388
1389 if let Some(element_state) = element_state.as_ref() {
1390 if cx.has_active_drag() {
1391 if let Some(pending_mouse_down) = element_state.pending_mouse_down.as_ref()
1392 {
1393 *pending_mouse_down.borrow_mut() = None;
1394 }
1395 if let Some(clicked_state) = element_state.clicked_state.as_ref() {
1396 *clicked_state.borrow_mut() = ElementClickedState::default();
1397 }
1398 }
1399 }
1400
1401 // Ensure we store a focus handle in our element state if we're focusable.
1402 // If there's an explicit focus handle we're tracking, use that. Otherwise
1403 // create a new handle and store it in the element state, which lives for as
1404 // as frames contain an element with this id.
1405 if self.focusable && self.tracked_focus_handle.is_none() {
1406 if let Some(element_state) = element_state.as_mut() {
1407 self.tracked_focus_handle = Some(
1408 element_state
1409 .focus_handle
1410 .get_or_insert_with(|| cx.focus_handle())
1411 .clone(),
1412 );
1413 }
1414 }
1415
1416 if let Some(scroll_handle) = self.tracked_scroll_handle.as_ref() {
1417 self.scroll_offset = Some(scroll_handle.0.borrow().offset.clone());
1418 } else if self.base_style.overflow.x == Some(Overflow::Scroll)
1419 || self.base_style.overflow.y == Some(Overflow::Scroll)
1420 {
1421 if let Some(element_state) = element_state.as_mut() {
1422 self.scroll_offset = Some(
1423 element_state
1424 .scroll_offset
1425 .get_or_insert_with(Rc::default)
1426 .clone(),
1427 );
1428 }
1429 }
1430
1431 let style = self.compute_style_internal(None, element_state.as_mut(), window, cx);
1432 let layout_id = f(style, window, cx);
1433 (layout_id, element_state)
1434 },
1435 )
1436 }
1437
1438 /// Commit the bounds of this element according to this interactivity state's configured styles.
1439 pub fn prepaint<R>(
1440 &mut self,
1441 global_id: Option<&GlobalElementId>,
1442 bounds: Bounds<Pixels>,
1443 content_size: Size<Pixels>,
1444 window: &mut Window,
1445 cx: &mut App,
1446 f: impl FnOnce(&Style, Point<Pixels>, Option<Hitbox>, &mut Window, &mut App) -> R,
1447 ) -> R {
1448 self.content_size = content_size;
1449 if let Some(focus_handle) = self.tracked_focus_handle.as_ref() {
1450 window.set_focus_handle(focus_handle, cx);
1451 }
1452 window.with_optional_element_state::<InteractiveElementState, _>(
1453 global_id,
1454 |element_state, window| {
1455 let mut element_state =
1456 element_state.map(|element_state| element_state.unwrap_or_default());
1457 let style = self.compute_style_internal(None, element_state.as_mut(), window, cx);
1458
1459 if let Some(element_state) = element_state.as_mut() {
1460 if let Some(clicked_state) = element_state.clicked_state.as_ref() {
1461 let clicked_state = clicked_state.borrow();
1462 self.active = Some(clicked_state.element);
1463 }
1464 if let Some(active_tooltip) = element_state.active_tooltip.as_ref() {
1465 if self.tooltip_builder.is_some() {
1466 self.tooltip_id = set_tooltip_on_window(active_tooltip, window);
1467 } else {
1468 // If there is no longer a tooltip builder, remove the active tooltip.
1469 element_state.active_tooltip.take();
1470 }
1471 }
1472 }
1473
1474 window.with_text_style(style.text_style().cloned(), |window| {
1475 window.with_content_mask(
1476 style.overflow_mask(bounds, window.rem_size()),
1477 |window| {
1478 let hitbox = if self.should_insert_hitbox(&style) {
1479 Some(window.insert_hitbox(bounds, self.occlude_mouse))
1480 } else {
1481 None
1482 };
1483
1484 let scroll_offset =
1485 self.clamp_scroll_position(bounds, &style, window, cx);
1486 let result = f(&style, scroll_offset, hitbox, window, cx);
1487 (result, element_state)
1488 },
1489 )
1490 })
1491 },
1492 )
1493 }
1494
1495 fn should_insert_hitbox(&self, style: &Style) -> bool {
1496 self.occlude_mouse
1497 || style.mouse_cursor.is_some()
1498 || self.group.is_some()
1499 || self.scroll_offset.is_some()
1500 || self.tracked_focus_handle.is_some()
1501 || self.hover_style.is_some()
1502 || self.group_hover_style.is_some()
1503 || self.hover_listener.is_some()
1504 || !self.mouse_up_listeners.is_empty()
1505 || !self.mouse_down_listeners.is_empty()
1506 || !self.mouse_move_listeners.is_empty()
1507 || !self.click_listeners.is_empty()
1508 || !self.scroll_wheel_listeners.is_empty()
1509 || self.drag_listener.is_some()
1510 || !self.drop_listeners.is_empty()
1511 || self.tooltip_builder.is_some()
1512 }
1513
1514 fn clamp_scroll_position(
1515 &self,
1516 bounds: Bounds<Pixels>,
1517 style: &Style,
1518 window: &mut Window,
1519 _cx: &mut App,
1520 ) -> Point<Pixels> {
1521 if let Some(scroll_offset) = self.scroll_offset.as_ref() {
1522 let mut scroll_to_bottom = false;
1523 if let Some(scroll_handle) = &self.tracked_scroll_handle {
1524 let mut state = scroll_handle.0.borrow_mut();
1525 state.overflow = style.overflow;
1526 scroll_to_bottom = mem::take(&mut state.scroll_to_bottom);
1527 }
1528
1529 let rem_size = window.rem_size();
1530 let padding_size = size(
1531 style
1532 .padding
1533 .left
1534 .to_pixels(bounds.size.width.into(), rem_size)
1535 + style
1536 .padding
1537 .right
1538 .to_pixels(bounds.size.width.into(), rem_size),
1539 style
1540 .padding
1541 .top
1542 .to_pixels(bounds.size.height.into(), rem_size)
1543 + style
1544 .padding
1545 .bottom
1546 .to_pixels(bounds.size.height.into(), rem_size),
1547 );
1548 let scroll_max = (self.content_size + padding_size - bounds.size).max(&Size::default());
1549 // Clamp scroll offset in case scroll max is smaller now (e.g., if children
1550 // were removed or the bounds became larger).
1551 let mut scroll_offset = scroll_offset.borrow_mut();
1552
1553 scroll_offset.x = scroll_offset.x.clamp(-scroll_max.width, px(0.));
1554 if scroll_to_bottom {
1555 scroll_offset.y = -scroll_max.height;
1556 } else {
1557 scroll_offset.y = scroll_offset.y.clamp(-scroll_max.height, px(0.));
1558 }
1559
1560 *scroll_offset
1561 } else {
1562 Point::default()
1563 }
1564 }
1565
1566 /// Paint this element according to this interactivity state's configured styles
1567 /// and bind the element's mouse and keyboard events.
1568 ///
1569 /// content_size is the size of the content of the element, which may be larger than the
1570 /// element's bounds if the element is scrollable.
1571 ///
1572 /// the final computed style will be passed to the provided function, along
1573 /// with the current scroll offset
1574 pub fn paint(
1575 &mut self,
1576 global_id: Option<&GlobalElementId>,
1577 bounds: Bounds<Pixels>,
1578 hitbox: Option<&Hitbox>,
1579 window: &mut Window,
1580 cx: &mut App,
1581 f: impl FnOnce(&Style, &mut Window, &mut App),
1582 ) {
1583 self.hovered = hitbox.map(|hitbox| hitbox.is_hovered(window));
1584 window.with_optional_element_state::<InteractiveElementState, _>(
1585 global_id,
1586 |element_state, window| {
1587 let mut element_state =
1588 element_state.map(|element_state| element_state.unwrap_or_default());
1589
1590 let style = self.compute_style_internal(hitbox, element_state.as_mut(), window, cx);
1591
1592 #[cfg(any(feature = "test-support", test))]
1593 if let Some(debug_selector) = &self.debug_selector {
1594 window
1595 .next_frame
1596 .debug_bounds
1597 .insert(debug_selector.clone(), bounds);
1598 }
1599
1600 self.paint_hover_group_handler(window, cx);
1601
1602 if style.visibility == Visibility::Hidden {
1603 return ((), element_state);
1604 }
1605
1606 window.with_element_opacity(style.opacity, |window| {
1607 style.paint(bounds, window, cx, |window: &mut Window, cx: &mut App| {
1608 window.with_text_style(style.text_style().cloned(), |window| {
1609 window.with_content_mask(
1610 style.overflow_mask(bounds, window.rem_size()),
1611 |window| {
1612 if let Some(hitbox) = hitbox {
1613 #[cfg(debug_assertions)]
1614 self.paint_debug_info(
1615 global_id, hitbox, &style, window, cx,
1616 );
1617
1618 if !cx.has_active_drag() {
1619 if let Some(mouse_cursor) = style.mouse_cursor {
1620 window.set_cursor_style(mouse_cursor, hitbox);
1621 }
1622 }
1623
1624 if let Some(group) = self.group.clone() {
1625 GroupHitboxes::push(group, hitbox.id, cx);
1626 }
1627
1628 self.paint_mouse_listeners(
1629 hitbox,
1630 element_state.as_mut(),
1631 window,
1632 cx,
1633 );
1634 self.paint_scroll_listener(hitbox, &style, window, cx);
1635 }
1636
1637 self.paint_keyboard_listeners(window, cx);
1638 f(&style, window, cx);
1639
1640 if hitbox.is_some() {
1641 if let Some(group) = self.group.as_ref() {
1642 GroupHitboxes::pop(group, cx);
1643 }
1644 }
1645 },
1646 );
1647 });
1648 });
1649 });
1650
1651 ((), element_state)
1652 },
1653 );
1654 }
1655
1656 #[cfg(debug_assertions)]
1657 fn paint_debug_info(
1658 &self,
1659 global_id: Option<&GlobalElementId>,
1660 hitbox: &Hitbox,
1661 style: &Style,
1662 window: &mut Window,
1663 cx: &mut App,
1664 ) {
1665 use crate::TextAlign;
1666
1667 if global_id.is_some()
1668 && (style.debug || style.debug_below || cx.has_global::<crate::DebugBelow>())
1669 && hitbox.is_hovered(window)
1670 {
1671 const FONT_SIZE: crate::Pixels = crate::Pixels(10.);
1672 let element_id = format!("{:?}", global_id.unwrap());
1673 let str_len = element_id.len();
1674
1675 let render_debug_text = |window: &mut Window| {
1676 if let Some(text) = window
1677 .text_system()
1678 .shape_text(
1679 element_id.into(),
1680 FONT_SIZE,
1681 &[window.text_style().to_run(str_len)],
1682 None,
1683 None,
1684 )
1685 .ok()
1686 .and_then(|mut text| text.pop())
1687 {
1688 text.paint(hitbox.origin, FONT_SIZE, TextAlign::Left, None, window, cx)
1689 .ok();
1690
1691 let text_bounds = crate::Bounds {
1692 origin: hitbox.origin,
1693 size: text.size(FONT_SIZE),
1694 };
1695 if self.location.is_some()
1696 && text_bounds.contains(&window.mouse_position())
1697 && window.modifiers().secondary()
1698 {
1699 let secondary_held = window.modifiers().secondary();
1700 window.on_key_event({
1701 move |e: &crate::ModifiersChangedEvent, _phase, window, _cx| {
1702 if e.modifiers.secondary() != secondary_held
1703 && text_bounds.contains(&window.mouse_position())
1704 {
1705 window.refresh();
1706 }
1707 }
1708 });
1709
1710 let was_hovered = hitbox.is_hovered(window);
1711 let current_view = window.current_view();
1712 window.on_mouse_event({
1713 let hitbox = hitbox.clone();
1714 move |_: &MouseMoveEvent, phase, window, cx| {
1715 if phase == DispatchPhase::Capture {
1716 let hovered = hitbox.is_hovered(window);
1717 if hovered != was_hovered {
1718 cx.notify(current_view)
1719 }
1720 }
1721 }
1722 });
1723
1724 window.on_mouse_event({
1725 let hitbox = hitbox.clone();
1726 let location = self.location.unwrap();
1727 move |e: &crate::MouseDownEvent, phase, window, cx| {
1728 if text_bounds.contains(&e.position)
1729 && phase.capture()
1730 && hitbox.is_hovered(window)
1731 {
1732 cx.stop_propagation();
1733 let Ok(dir) = std::env::current_dir() else {
1734 return;
1735 };
1736
1737 eprintln!(
1738 "This element was created at:\n{}:{}:{}",
1739 dir.join(location.file()).to_string_lossy(),
1740 location.line(),
1741 location.column()
1742 );
1743 }
1744 }
1745 });
1746 window.paint_quad(crate::outline(
1747 crate::Bounds {
1748 origin: hitbox.origin
1749 + crate::point(crate::px(0.), FONT_SIZE - px(2.)),
1750 size: crate::Size {
1751 width: text_bounds.size.width,
1752 height: crate::px(1.),
1753 },
1754 },
1755 crate::red(),
1756 ))
1757 }
1758 }
1759 };
1760
1761 window.with_text_style(
1762 Some(crate::TextStyleRefinement {
1763 color: Some(crate::red()),
1764 line_height: Some(FONT_SIZE.into()),
1765 background_color: Some(crate::white()),
1766 ..Default::default()
1767 }),
1768 render_debug_text,
1769 )
1770 }
1771 }
1772
1773 fn paint_mouse_listeners(
1774 &mut self,
1775 hitbox: &Hitbox,
1776 element_state: Option<&mut InteractiveElementState>,
1777 window: &mut Window,
1778 cx: &mut App,
1779 ) {
1780 // If this element can be focused, register a mouse down listener
1781 // that will automatically transfer focus when hitting the element.
1782 // This behavior can be suppressed by using `cx.prevent_default()`.
1783 if let Some(focus_handle) = self.tracked_focus_handle.clone() {
1784 let hitbox = hitbox.clone();
1785 window.on_mouse_event(move |_: &MouseDownEvent, phase, window, _| {
1786 if phase == DispatchPhase::Bubble
1787 && hitbox.is_hovered(window)
1788 && !window.default_prevented()
1789 {
1790 window.focus(&focus_handle);
1791 // If there is a parent that is also focusable, prevent it
1792 // from transferring focus because we already did so.
1793 window.prevent_default();
1794 }
1795 });
1796 }
1797
1798 for listener in self.mouse_down_listeners.drain(..) {
1799 let hitbox = hitbox.clone();
1800 window.on_mouse_event(move |event: &MouseDownEvent, phase, window, cx| {
1801 listener(event, phase, &hitbox, window, cx);
1802 })
1803 }
1804
1805 for listener in self.mouse_up_listeners.drain(..) {
1806 let hitbox = hitbox.clone();
1807 window.on_mouse_event(move |event: &MouseUpEvent, phase, window, cx| {
1808 listener(event, phase, &hitbox, window, cx);
1809 })
1810 }
1811
1812 for listener in self.mouse_move_listeners.drain(..) {
1813 let hitbox = hitbox.clone();
1814 window.on_mouse_event(move |event: &MouseMoveEvent, phase, window, cx| {
1815 listener(event, phase, &hitbox, window, cx);
1816 })
1817 }
1818
1819 for listener in self.scroll_wheel_listeners.drain(..) {
1820 let hitbox = hitbox.clone();
1821 window.on_mouse_event(move |event: &ScrollWheelEvent, phase, window, cx| {
1822 listener(event, phase, &hitbox, window, cx);
1823 })
1824 }
1825
1826 if self.hover_style.is_some()
1827 || self.base_style.mouse_cursor.is_some()
1828 || cx.active_drag.is_some() && !self.drag_over_styles.is_empty()
1829 {
1830 let hitbox = hitbox.clone();
1831 let was_hovered = hitbox.is_hovered(window);
1832 let current_view = window.current_view();
1833 window.on_mouse_event(move |_: &MouseMoveEvent, phase, window, cx| {
1834 let hovered = hitbox.is_hovered(window);
1835 if phase == DispatchPhase::Capture && hovered != was_hovered {
1836 cx.notify(current_view);
1837 }
1838 });
1839 }
1840
1841 let mut drag_listener = mem::take(&mut self.drag_listener);
1842 let drop_listeners = mem::take(&mut self.drop_listeners);
1843 let click_listeners = mem::take(&mut self.click_listeners);
1844 let can_drop_predicate = mem::take(&mut self.can_drop_predicate);
1845
1846 if !drop_listeners.is_empty() {
1847 let hitbox = hitbox.clone();
1848 window.on_mouse_event({
1849 move |_: &MouseUpEvent, phase, window, cx| {
1850 if let Some(drag) = &cx.active_drag {
1851 if phase == DispatchPhase::Bubble && hitbox.is_hovered(window) {
1852 let drag_state_type = drag.value.as_ref().type_id();
1853 for (drop_state_type, listener) in &drop_listeners {
1854 if *drop_state_type == drag_state_type {
1855 let drag = cx
1856 .active_drag
1857 .take()
1858 .expect("checked for type drag state type above");
1859
1860 let mut can_drop = true;
1861 if let Some(predicate) = &can_drop_predicate {
1862 can_drop = predicate(drag.value.as_ref(), window, cx);
1863 }
1864
1865 if can_drop {
1866 listener(drag.value.as_ref(), window, cx);
1867 window.refresh();
1868 cx.stop_propagation();
1869 }
1870 }
1871 }
1872 }
1873 }
1874 }
1875 });
1876 }
1877
1878 if let Some(element_state) = element_state {
1879 if !click_listeners.is_empty() || drag_listener.is_some() {
1880 let pending_mouse_down = element_state
1881 .pending_mouse_down
1882 .get_or_insert_with(Default::default)
1883 .clone();
1884
1885 let clicked_state = element_state
1886 .clicked_state
1887 .get_or_insert_with(Default::default)
1888 .clone();
1889
1890 window.on_mouse_event({
1891 let pending_mouse_down = pending_mouse_down.clone();
1892 let hitbox = hitbox.clone();
1893 move |event: &MouseDownEvent, phase, window, _cx| {
1894 if phase == DispatchPhase::Bubble
1895 && event.button == MouseButton::Left
1896 && hitbox.is_hovered(window)
1897 {
1898 *pending_mouse_down.borrow_mut() = Some(event.clone());
1899 window.refresh();
1900 }
1901 }
1902 });
1903
1904 window.on_mouse_event({
1905 let pending_mouse_down = pending_mouse_down.clone();
1906 let hitbox = hitbox.clone();
1907 move |event: &MouseMoveEvent, phase, window, cx| {
1908 if phase == DispatchPhase::Capture {
1909 return;
1910 }
1911
1912 let mut pending_mouse_down = pending_mouse_down.borrow_mut();
1913 if let Some(mouse_down) = pending_mouse_down.clone() {
1914 if !cx.has_active_drag()
1915 && (event.position - mouse_down.position).magnitude()
1916 > DRAG_THRESHOLD
1917 {
1918 if let Some((drag_value, drag_listener)) = drag_listener.take() {
1919 *clicked_state.borrow_mut() = ElementClickedState::default();
1920 let cursor_offset = event.position - hitbox.origin;
1921 let drag = (drag_listener)(
1922 drag_value.as_ref(),
1923 cursor_offset,
1924 window,
1925 cx,
1926 );
1927 cx.active_drag = Some(AnyDrag {
1928 view: drag,
1929 value: drag_value,
1930 cursor_offset,
1931 });
1932 pending_mouse_down.take();
1933 window.refresh();
1934 cx.stop_propagation();
1935 }
1936 }
1937 }
1938 }
1939 });
1940
1941 window.on_mouse_event({
1942 let mut captured_mouse_down = None;
1943 let hitbox = hitbox.clone();
1944 move |event: &MouseUpEvent, phase, window, cx| match phase {
1945 // Clear the pending mouse down during the capture phase,
1946 // so that it happens even if another event handler stops
1947 // propagation.
1948 DispatchPhase::Capture => {
1949 let mut pending_mouse_down = pending_mouse_down.borrow_mut();
1950 if pending_mouse_down.is_some() && hitbox.is_hovered(window) {
1951 captured_mouse_down = pending_mouse_down.take();
1952 window.refresh();
1953 } else if pending_mouse_down.is_some() {
1954 // Clear the pending mouse down event (without firing click handlers)
1955 // if the hitbox is not being hovered.
1956 // This avoids dragging elements that changed their position
1957 // immediately after being clicked.
1958 // See https://github.com/zed-industries/zed/issues/24600 for more details
1959 pending_mouse_down.take();
1960 window.refresh();
1961 }
1962 }
1963 // Fire click handlers during the bubble phase.
1964 DispatchPhase::Bubble => {
1965 if let Some(mouse_down) = captured_mouse_down.take() {
1966 let mouse_click = ClickEvent {
1967 down: mouse_down,
1968 up: event.clone(),
1969 };
1970 for listener in &click_listeners {
1971 listener(&mouse_click, window, cx);
1972 }
1973 }
1974 }
1975 }
1976 });
1977 }
1978
1979 if let Some(hover_listener) = self.hover_listener.take() {
1980 let hitbox = hitbox.clone();
1981 let was_hovered = element_state
1982 .hover_state
1983 .get_or_insert_with(Default::default)
1984 .clone();
1985 let has_mouse_down = element_state
1986 .pending_mouse_down
1987 .get_or_insert_with(Default::default)
1988 .clone();
1989
1990 window.on_mouse_event(move |_: &MouseMoveEvent, phase, window, cx| {
1991 if phase != DispatchPhase::Bubble {
1992 return;
1993 }
1994 let is_hovered = has_mouse_down.borrow().is_none()
1995 && !cx.has_active_drag()
1996 && hitbox.is_hovered(window);
1997 let mut was_hovered = was_hovered.borrow_mut();
1998
1999 if is_hovered != *was_hovered {
2000 *was_hovered = is_hovered;
2001 drop(was_hovered);
2002
2003 hover_listener(&is_hovered, window, cx);
2004 }
2005 });
2006 }
2007
2008 if let Some(tooltip_builder) = self.tooltip_builder.take() {
2009 let active_tooltip = element_state
2010 .active_tooltip
2011 .get_or_insert_with(Default::default)
2012 .clone();
2013 let pending_mouse_down = element_state
2014 .pending_mouse_down
2015 .get_or_insert_with(Default::default)
2016 .clone();
2017
2018 let tooltip_is_hoverable = tooltip_builder.hoverable;
2019 let build_tooltip = Rc::new(move |window: &mut Window, cx: &mut App| {
2020 Some(((tooltip_builder.build)(window, cx), tooltip_is_hoverable))
2021 });
2022 // Use bounds instead of testing hitbox since this is called during prepaint.
2023 let check_is_hovered_during_prepaint = Rc::new({
2024 let pending_mouse_down = pending_mouse_down.clone();
2025 let source_bounds = hitbox.bounds;
2026 move |window: &Window| {
2027 pending_mouse_down.borrow().is_none()
2028 && source_bounds.contains(&window.mouse_position())
2029 }
2030 });
2031 let check_is_hovered = Rc::new({
2032 let hitbox = hitbox.clone();
2033 move |window: &Window| {
2034 pending_mouse_down.borrow().is_none() && hitbox.is_hovered(window)
2035 }
2036 });
2037 register_tooltip_mouse_handlers(
2038 &active_tooltip,
2039 self.tooltip_id,
2040 build_tooltip,
2041 check_is_hovered,
2042 check_is_hovered_during_prepaint,
2043 window,
2044 );
2045 }
2046
2047 let active_state = element_state
2048 .clicked_state
2049 .get_or_insert_with(Default::default)
2050 .clone();
2051 if active_state.borrow().is_clicked() {
2052 window.on_mouse_event(move |_: &MouseUpEvent, phase, window, _cx| {
2053 if phase == DispatchPhase::Capture {
2054 *active_state.borrow_mut() = ElementClickedState::default();
2055 window.refresh();
2056 }
2057 });
2058 } else {
2059 let active_group_hitbox = self
2060 .group_active_style
2061 .as_ref()
2062 .and_then(|group_active| GroupHitboxes::get(&group_active.group, cx));
2063 let hitbox = hitbox.clone();
2064 window.on_mouse_event(move |_: &MouseDownEvent, phase, window, _cx| {
2065 if phase == DispatchPhase::Bubble && !window.default_prevented() {
2066 let group_hovered = active_group_hitbox
2067 .map_or(false, |group_hitbox_id| group_hitbox_id.is_hovered(window));
2068 let element_hovered = hitbox.is_hovered(window);
2069 if group_hovered || element_hovered {
2070 *active_state.borrow_mut() = ElementClickedState {
2071 group: group_hovered,
2072 element: element_hovered,
2073 };
2074 window.refresh();
2075 }
2076 }
2077 });
2078 }
2079 }
2080 }
2081
2082 fn paint_keyboard_listeners(&mut self, window: &mut Window, _cx: &mut App) {
2083 let key_down_listeners = mem::take(&mut self.key_down_listeners);
2084 let key_up_listeners = mem::take(&mut self.key_up_listeners);
2085 let modifiers_changed_listeners = mem::take(&mut self.modifiers_changed_listeners);
2086 let action_listeners = mem::take(&mut self.action_listeners);
2087 if let Some(context) = self.key_context.clone() {
2088 window.set_key_context(context);
2089 }
2090
2091 for listener in key_down_listeners {
2092 window.on_key_event(move |event: &KeyDownEvent, phase, window, cx| {
2093 listener(event, phase, window, cx);
2094 })
2095 }
2096
2097 for listener in key_up_listeners {
2098 window.on_key_event(move |event: &KeyUpEvent, phase, window, cx| {
2099 listener(event, phase, window, cx);
2100 })
2101 }
2102
2103 for listener in modifiers_changed_listeners {
2104 window.on_modifiers_changed(move |event: &ModifiersChangedEvent, window, cx| {
2105 listener(event, window, cx);
2106 })
2107 }
2108
2109 for (action_type, listener) in action_listeners {
2110 window.on_action(action_type, listener)
2111 }
2112 }
2113
2114 fn paint_hover_group_handler(&self, window: &mut Window, cx: &mut App) {
2115 let group_hitbox = self
2116 .group_hover_style
2117 .as_ref()
2118 .and_then(|group_hover| GroupHitboxes::get(&group_hover.group, cx));
2119
2120 if let Some(group_hitbox) = group_hitbox {
2121 let was_hovered = group_hitbox.is_hovered(window);
2122 let current_view = window.current_view();
2123 window.on_mouse_event(move |_: &MouseMoveEvent, phase, window, cx| {
2124 let hovered = group_hitbox.is_hovered(window);
2125 if phase == DispatchPhase::Capture && hovered != was_hovered {
2126 cx.notify(current_view);
2127 }
2128 });
2129 }
2130 }
2131
2132 fn paint_scroll_listener(
2133 &self,
2134 hitbox: &Hitbox,
2135 style: &Style,
2136 window: &mut Window,
2137 _cx: &mut App,
2138 ) {
2139 if let Some(scroll_offset) = self.scroll_offset.clone() {
2140 let overflow = style.overflow;
2141 let allow_concurrent_scroll = style.allow_concurrent_scroll;
2142 let restrict_scroll_to_axis = style.restrict_scroll_to_axis;
2143 let line_height = window.line_height();
2144 let hitbox = hitbox.clone();
2145 let current_view = window.current_view();
2146 window.on_mouse_event(move |event: &ScrollWheelEvent, phase, window, cx| {
2147 if phase == DispatchPhase::Bubble && hitbox.is_hovered(window) {
2148 let mut scroll_offset = scroll_offset.borrow_mut();
2149 let old_scroll_offset = *scroll_offset;
2150 let delta = event.delta.pixel_delta(line_height);
2151
2152 let mut delta_x = Pixels::ZERO;
2153 if overflow.x == Overflow::Scroll {
2154 if !delta.x.is_zero() {
2155 delta_x = delta.x;
2156 } else if !restrict_scroll_to_axis && overflow.y != Overflow::Scroll {
2157 delta_x = delta.y;
2158 }
2159 }
2160 let mut delta_y = Pixels::ZERO;
2161 if overflow.y == Overflow::Scroll {
2162 if !delta.y.is_zero() {
2163 delta_y = delta.y;
2164 } else if !restrict_scroll_to_axis && overflow.x != Overflow::Scroll {
2165 delta_y = delta.x;
2166 }
2167 }
2168 if !allow_concurrent_scroll && !delta_x.is_zero() && !delta_y.is_zero() {
2169 if delta_x.abs() > delta_y.abs() {
2170 delta_y = Pixels::ZERO;
2171 } else {
2172 delta_x = Pixels::ZERO;
2173 }
2174 }
2175 scroll_offset.y += delta_y;
2176 scroll_offset.x += delta_x;
2177 cx.stop_propagation();
2178 if *scroll_offset != old_scroll_offset {
2179 cx.notify(current_view);
2180 }
2181 }
2182 });
2183 }
2184 }
2185
2186 /// Compute the visual style for this element, based on the current bounds and the element's state.
2187 pub fn compute_style(
2188 &self,
2189 global_id: Option<&GlobalElementId>,
2190 hitbox: Option<&Hitbox>,
2191 window: &mut Window,
2192 cx: &mut App,
2193 ) -> Style {
2194 window.with_optional_element_state(global_id, |element_state, window| {
2195 let mut element_state =
2196 element_state.map(|element_state| element_state.unwrap_or_default());
2197 let style = self.compute_style_internal(hitbox, element_state.as_mut(), window, cx);
2198 (style, element_state)
2199 })
2200 }
2201
2202 /// Called from internal methods that have already called with_element_state.
2203 fn compute_style_internal(
2204 &self,
2205 hitbox: Option<&Hitbox>,
2206 element_state: Option<&mut InteractiveElementState>,
2207 window: &mut Window,
2208 cx: &mut App,
2209 ) -> Style {
2210 let mut style = Style::default();
2211 style.refine(&self.base_style);
2212
2213 if let Some(focus_handle) = self.tracked_focus_handle.as_ref() {
2214 if let Some(in_focus_style) = self.in_focus_style.as_ref() {
2215 if focus_handle.within_focused(window, cx) {
2216 style.refine(in_focus_style);
2217 }
2218 }
2219
2220 if let Some(focus_style) = self.focus_style.as_ref() {
2221 if focus_handle.is_focused(window) {
2222 style.refine(focus_style);
2223 }
2224 }
2225 }
2226
2227 if let Some(hitbox) = hitbox {
2228 if !cx.has_active_drag() {
2229 if let Some(group_hover) = self.group_hover_style.as_ref() {
2230 if let Some(group_hitbox_id) = GroupHitboxes::get(&group_hover.group, cx) {
2231 if group_hitbox_id.is_hovered(window) {
2232 style.refine(&group_hover.style);
2233 }
2234 }
2235 }
2236
2237 if let Some(hover_style) = self.hover_style.as_ref() {
2238 if hitbox.is_hovered(window) {
2239 style.refine(hover_style);
2240 }
2241 }
2242 }
2243
2244 if let Some(drag) = cx.active_drag.take() {
2245 let mut can_drop = true;
2246 if let Some(can_drop_predicate) = &self.can_drop_predicate {
2247 can_drop = can_drop_predicate(drag.value.as_ref(), window, cx);
2248 }
2249
2250 if can_drop {
2251 for (state_type, group_drag_style) in &self.group_drag_over_styles {
2252 if let Some(group_hitbox_id) =
2253 GroupHitboxes::get(&group_drag_style.group, cx)
2254 {
2255 if *state_type == drag.value.as_ref().type_id()
2256 && group_hitbox_id.is_hovered(window)
2257 {
2258 style.refine(&group_drag_style.style);
2259 }
2260 }
2261 }
2262
2263 for (state_type, build_drag_over_style) in &self.drag_over_styles {
2264 if *state_type == drag.value.as_ref().type_id() && hitbox.is_hovered(window)
2265 {
2266 style.refine(&build_drag_over_style(drag.value.as_ref(), window, cx));
2267 }
2268 }
2269 }
2270
2271 cx.active_drag = Some(drag);
2272 }
2273 }
2274
2275 if let Some(element_state) = element_state {
2276 let clicked_state = element_state
2277 .clicked_state
2278 .get_or_insert_with(Default::default)
2279 .borrow();
2280 if clicked_state.group {
2281 if let Some(group) = self.group_active_style.as_ref() {
2282 style.refine(&group.style)
2283 }
2284 }
2285
2286 if let Some(active_style) = self.active_style.as_ref() {
2287 if clicked_state.element {
2288 style.refine(active_style)
2289 }
2290 }
2291 }
2292
2293 style
2294 }
2295}
2296
2297/// The per-frame state of an interactive element. Used for tracking stateful interactions like clicks
2298/// and scroll offsets.
2299#[derive(Default)]
2300pub struct InteractiveElementState {
2301 pub(crate) focus_handle: Option<FocusHandle>,
2302 pub(crate) clicked_state: Option<Rc<RefCell<ElementClickedState>>>,
2303 pub(crate) hover_state: Option<Rc<RefCell<bool>>>,
2304 pub(crate) pending_mouse_down: Option<Rc<RefCell<Option<MouseDownEvent>>>>,
2305 pub(crate) scroll_offset: Option<Rc<RefCell<Point<Pixels>>>>,
2306 pub(crate) active_tooltip: Option<Rc<RefCell<Option<ActiveTooltip>>>>,
2307}
2308
2309/// Whether or not the element or a group that contains it is clicked by the mouse.
2310#[derive(Copy, Clone, Default, Eq, PartialEq)]
2311pub struct ElementClickedState {
2312 /// True if this element's group has been clicked, false otherwise
2313 pub group: bool,
2314
2315 /// True if this element has been clicked, false otherwise
2316 pub element: bool,
2317}
2318
2319impl ElementClickedState {
2320 fn is_clicked(&self) -> bool {
2321 self.group || self.element
2322 }
2323}
2324
2325pub(crate) enum ActiveTooltip {
2326 /// Currently delaying before showing the tooltip.
2327 WaitingForShow { _task: Task<()> },
2328 /// Tooltip is visible, element was hovered or for hoverable tooltips, the tooltip was hovered.
2329 Visible {
2330 tooltip: AnyTooltip,
2331 is_hoverable: bool,
2332 },
2333 /// Tooltip is visible and hoverable, but the mouse is no longer hovering. Currently delaying
2334 /// before hiding it.
2335 WaitingForHide {
2336 tooltip: AnyTooltip,
2337 _task: Task<()>,
2338 },
2339}
2340
2341pub(crate) fn clear_active_tooltip(
2342 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2343 window: &mut Window,
2344) {
2345 match active_tooltip.borrow_mut().take() {
2346 None => {}
2347 Some(ActiveTooltip::WaitingForShow { .. }) => {}
2348 Some(ActiveTooltip::Visible { .. }) => window.refresh(),
2349 Some(ActiveTooltip::WaitingForHide { .. }) => window.refresh(),
2350 }
2351}
2352
2353pub(crate) fn clear_active_tooltip_if_not_hoverable(
2354 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2355 window: &mut Window,
2356) {
2357 let should_clear = match active_tooltip.borrow().as_ref() {
2358 None => false,
2359 Some(ActiveTooltip::WaitingForShow { .. }) => false,
2360 Some(ActiveTooltip::Visible { is_hoverable, .. }) => !is_hoverable,
2361 Some(ActiveTooltip::WaitingForHide { .. }) => false,
2362 };
2363 if should_clear {
2364 active_tooltip.borrow_mut().take();
2365 window.refresh();
2366 }
2367}
2368
2369pub(crate) fn set_tooltip_on_window(
2370 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2371 window: &mut Window,
2372) -> Option<TooltipId> {
2373 let tooltip = match active_tooltip.borrow().as_ref() {
2374 None => return None,
2375 Some(ActiveTooltip::WaitingForShow { .. }) => return None,
2376 Some(ActiveTooltip::Visible { tooltip, .. }) => tooltip.clone(),
2377 Some(ActiveTooltip::WaitingForHide { tooltip, .. }) => tooltip.clone(),
2378 };
2379 Some(window.set_tooltip(tooltip))
2380}
2381
2382pub(crate) fn register_tooltip_mouse_handlers(
2383 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2384 tooltip_id: Option<TooltipId>,
2385 build_tooltip: Rc<dyn Fn(&mut Window, &mut App) -> Option<(AnyView, bool)>>,
2386 check_is_hovered: Rc<dyn Fn(&Window) -> bool>,
2387 check_is_hovered_during_prepaint: Rc<dyn Fn(&Window) -> bool>,
2388 window: &mut Window,
2389) {
2390 window.on_mouse_event({
2391 let active_tooltip = active_tooltip.clone();
2392 let build_tooltip = build_tooltip.clone();
2393 let check_is_hovered = check_is_hovered.clone();
2394 move |_: &MouseMoveEvent, phase, window, cx| {
2395 handle_tooltip_mouse_move(
2396 &active_tooltip,
2397 &build_tooltip,
2398 &check_is_hovered,
2399 &check_is_hovered_during_prepaint,
2400 phase,
2401 window,
2402 cx,
2403 )
2404 }
2405 });
2406
2407 window.on_mouse_event({
2408 let active_tooltip = active_tooltip.clone();
2409 move |_: &MouseDownEvent, _phase, window: &mut Window, _cx| {
2410 if !tooltip_id.map_or(false, |tooltip_id| tooltip_id.is_hovered(window)) {
2411 clear_active_tooltip_if_not_hoverable(&active_tooltip, window);
2412 }
2413 }
2414 });
2415
2416 window.on_mouse_event({
2417 let active_tooltip = active_tooltip.clone();
2418 move |_: &ScrollWheelEvent, _phase, window: &mut Window, _cx| {
2419 if !tooltip_id.map_or(false, |tooltip_id| tooltip_id.is_hovered(window)) {
2420 clear_active_tooltip_if_not_hoverable(&active_tooltip, window);
2421 }
2422 }
2423 });
2424}
2425
2426/// Handles displaying tooltips when an element is hovered.
2427///
2428/// The mouse hovering logic also relies on being called from window prepaint in order to handle the
2429/// case where the element the tooltip is on is not rendered - in that case its mouse listeners are
2430/// also not registered. During window prepaint, the hitbox information is not available, so
2431/// `check_is_hovered_during_prepaint` is used which bases the check off of the absolute bounds of
2432/// the element.
2433///
2434/// TODO: There's a minor bug due to the use of absolute bounds while checking during prepaint - it
2435/// does not know if the hitbox is occluded. In the case where a tooltip gets displayed and then
2436/// gets occluded after display, it will stick around until the mouse exits the hover bounds.
2437fn handle_tooltip_mouse_move(
2438 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2439 build_tooltip: &Rc<dyn Fn(&mut Window, &mut App) -> Option<(AnyView, bool)>>,
2440 check_is_hovered: &Rc<dyn Fn(&Window) -> bool>,
2441 check_is_hovered_during_prepaint: &Rc<dyn Fn(&Window) -> bool>,
2442 phase: DispatchPhase,
2443 window: &mut Window,
2444 cx: &mut App,
2445) {
2446 // Separates logic for what mutation should occur from applying it, to avoid overlapping
2447 // RefCell borrows.
2448 enum Action {
2449 None,
2450 CancelShow,
2451 ScheduleShow,
2452 }
2453
2454 let action = match active_tooltip.borrow().as_ref() {
2455 None => {
2456 let is_hovered = check_is_hovered(window);
2457 if is_hovered && phase.bubble() {
2458 Action::ScheduleShow
2459 } else {
2460 Action::None
2461 }
2462 }
2463 Some(ActiveTooltip::WaitingForShow { .. }) => {
2464 let is_hovered = check_is_hovered(window);
2465 if is_hovered {
2466 Action::None
2467 } else {
2468 Action::CancelShow
2469 }
2470 }
2471 // These are handled in check_visible_and_update.
2472 Some(ActiveTooltip::Visible { .. }) | Some(ActiveTooltip::WaitingForHide { .. }) => {
2473 Action::None
2474 }
2475 };
2476
2477 match action {
2478 Action::None => {}
2479 Action::CancelShow => {
2480 // Cancel waiting to show tooltip when it is no longer hovered.
2481 active_tooltip.borrow_mut().take();
2482 }
2483 Action::ScheduleShow => {
2484 let delayed_show_task = window.spawn(cx, {
2485 let active_tooltip = active_tooltip.clone();
2486 let build_tooltip = build_tooltip.clone();
2487 let check_is_hovered_during_prepaint = check_is_hovered_during_prepaint.clone();
2488 async move |cx| {
2489 cx.background_executor().timer(TOOLTIP_SHOW_DELAY).await;
2490 cx.update(|window, cx| {
2491 let new_tooltip =
2492 build_tooltip(window, cx).map(|(view, tooltip_is_hoverable)| {
2493 let active_tooltip = active_tooltip.clone();
2494 ActiveTooltip::Visible {
2495 tooltip: AnyTooltip {
2496 view,
2497 mouse_position: window.mouse_position(),
2498 check_visible_and_update: Rc::new(
2499 move |tooltip_bounds, window, cx| {
2500 handle_tooltip_check_visible_and_update(
2501 &active_tooltip,
2502 tooltip_is_hoverable,
2503 &check_is_hovered_during_prepaint,
2504 tooltip_bounds,
2505 window,
2506 cx,
2507 )
2508 },
2509 ),
2510 },
2511 is_hoverable: tooltip_is_hoverable,
2512 }
2513 });
2514 *active_tooltip.borrow_mut() = new_tooltip;
2515 window.refresh();
2516 })
2517 .ok();
2518 }
2519 });
2520 active_tooltip
2521 .borrow_mut()
2522 .replace(ActiveTooltip::WaitingForShow {
2523 _task: delayed_show_task,
2524 });
2525 }
2526 }
2527}
2528
2529/// Returns a callback which will be called by window prepaint to update tooltip visibility. The
2530/// purpose of doing this logic here instead of the mouse move handler is that the mouse move
2531/// handler won't get called when the element is not painted (e.g. via use of `visible_on_hover`).
2532fn handle_tooltip_check_visible_and_update(
2533 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2534 tooltip_is_hoverable: bool,
2535 check_is_hovered: &Rc<dyn Fn(&Window) -> bool>,
2536 tooltip_bounds: Bounds<Pixels>,
2537 window: &mut Window,
2538 cx: &mut App,
2539) -> bool {
2540 // Separates logic for what mutation should occur from applying it, to avoid overlapping RefCell
2541 // borrows.
2542 enum Action {
2543 None,
2544 Hide,
2545 ScheduleHide(AnyTooltip),
2546 CancelHide(AnyTooltip),
2547 }
2548
2549 let is_hovered = check_is_hovered(window)
2550 || (tooltip_is_hoverable && tooltip_bounds.contains(&window.mouse_position()));
2551 let action = match active_tooltip.borrow().as_ref() {
2552 Some(ActiveTooltip::Visible { tooltip, .. }) => {
2553 if is_hovered {
2554 Action::None
2555 } else {
2556 if tooltip_is_hoverable {
2557 Action::ScheduleHide(tooltip.clone())
2558 } else {
2559 Action::Hide
2560 }
2561 }
2562 }
2563 Some(ActiveTooltip::WaitingForHide { tooltip, .. }) => {
2564 if is_hovered {
2565 Action::CancelHide(tooltip.clone())
2566 } else {
2567 Action::None
2568 }
2569 }
2570 None | Some(ActiveTooltip::WaitingForShow { .. }) => Action::None,
2571 };
2572
2573 match action {
2574 Action::None => {}
2575 Action::Hide => clear_active_tooltip(&active_tooltip, window),
2576 Action::ScheduleHide(tooltip) => {
2577 let delayed_hide_task = window.spawn(cx, {
2578 let active_tooltip = active_tooltip.clone();
2579 async move |cx| {
2580 cx.background_executor()
2581 .timer(HOVERABLE_TOOLTIP_HIDE_DELAY)
2582 .await;
2583 if active_tooltip.borrow_mut().take().is_some() {
2584 cx.update(|window, _cx| window.refresh()).ok();
2585 }
2586 }
2587 });
2588 active_tooltip
2589 .borrow_mut()
2590 .replace(ActiveTooltip::WaitingForHide {
2591 tooltip,
2592 _task: delayed_hide_task,
2593 });
2594 }
2595 Action::CancelHide(tooltip) => {
2596 // Cancel waiting to hide tooltip when it becomes hovered.
2597 active_tooltip.borrow_mut().replace(ActiveTooltip::Visible {
2598 tooltip,
2599 is_hoverable: true,
2600 });
2601 }
2602 }
2603
2604 active_tooltip.borrow().is_some()
2605}
2606
2607#[derive(Default)]
2608pub(crate) struct GroupHitboxes(HashMap<SharedString, SmallVec<[HitboxId; 1]>>);
2609
2610impl Global for GroupHitboxes {}
2611
2612impl GroupHitboxes {
2613 pub fn get(name: &SharedString, cx: &mut App) -> Option<HitboxId> {
2614 cx.default_global::<Self>()
2615 .0
2616 .get(name)
2617 .and_then(|bounds_stack| bounds_stack.last())
2618 .cloned()
2619 }
2620
2621 pub fn push(name: SharedString, hitbox_id: HitboxId, cx: &mut App) {
2622 cx.default_global::<Self>()
2623 .0
2624 .entry(name)
2625 .or_default()
2626 .push(hitbox_id);
2627 }
2628
2629 pub fn pop(name: &SharedString, cx: &mut App) {
2630 cx.default_global::<Self>().0.get_mut(name).unwrap().pop();
2631 }
2632}
2633
2634/// A wrapper around an element that can be focused.
2635pub struct FocusableWrapper<E> {
2636 /// The element that is focusable
2637 pub element: E,
2638}
2639
2640impl<E: InteractiveElement> FocusableElement for FocusableWrapper<E> {}
2641
2642impl<E> InteractiveElement for FocusableWrapper<E>
2643where
2644 E: InteractiveElement,
2645{
2646 fn interactivity(&mut self) -> &mut Interactivity {
2647 self.element.interactivity()
2648 }
2649}
2650
2651impl<E: StatefulInteractiveElement> StatefulInteractiveElement for FocusableWrapper<E> {}
2652
2653impl<E> Styled for FocusableWrapper<E>
2654where
2655 E: Styled,
2656{
2657 fn style(&mut self) -> &mut StyleRefinement {
2658 self.element.style()
2659 }
2660}
2661
2662impl FocusableWrapper<Div> {
2663 /// Add a listener to be called when the children of this `Div` are prepainted.
2664 /// This allows you to store the [`Bounds`] of the children for later use.
2665 pub fn on_children_prepainted(
2666 mut self,
2667 listener: impl Fn(Vec<Bounds<Pixels>>, &mut Window, &mut App) + 'static,
2668 ) -> Self {
2669 self.element = self.element.on_children_prepainted(listener);
2670 self
2671 }
2672}
2673
2674impl<E> Element for FocusableWrapper<E>
2675where
2676 E: Element,
2677{
2678 type RequestLayoutState = E::RequestLayoutState;
2679 type PrepaintState = E::PrepaintState;
2680
2681 fn id(&self) -> Option<ElementId> {
2682 self.element.id()
2683 }
2684
2685 fn request_layout(
2686 &mut self,
2687 id: Option<&GlobalElementId>,
2688 window: &mut Window,
2689 cx: &mut App,
2690 ) -> (LayoutId, Self::RequestLayoutState) {
2691 self.element.request_layout(id, window, cx)
2692 }
2693
2694 fn prepaint(
2695 &mut self,
2696 id: Option<&GlobalElementId>,
2697 bounds: Bounds<Pixels>,
2698 state: &mut Self::RequestLayoutState,
2699 window: &mut Window,
2700 cx: &mut App,
2701 ) -> E::PrepaintState {
2702 self.element.prepaint(id, bounds, state, window, cx)
2703 }
2704
2705 fn paint(
2706 &mut self,
2707 id: Option<&GlobalElementId>,
2708 bounds: Bounds<Pixels>,
2709 request_layout: &mut Self::RequestLayoutState,
2710 prepaint: &mut Self::PrepaintState,
2711 window: &mut Window,
2712 cx: &mut App,
2713 ) {
2714 self.element
2715 .paint(id, bounds, request_layout, prepaint, window, cx)
2716 }
2717}
2718
2719impl<E> IntoElement for FocusableWrapper<E>
2720where
2721 E: IntoElement,
2722{
2723 type Element = E::Element;
2724
2725 fn into_element(self) -> Self::Element {
2726 self.element.into_element()
2727 }
2728}
2729
2730impl<E> ParentElement for FocusableWrapper<E>
2731where
2732 E: ParentElement,
2733{
2734 fn extend(&mut self, elements: impl IntoIterator<Item = AnyElement>) {
2735 self.element.extend(elements)
2736 }
2737}
2738
2739/// A wrapper around an element that can store state, produced after assigning an ElementId.
2740pub struct Stateful<E> {
2741 pub(crate) element: E,
2742}
2743
2744impl<E> Styled for Stateful<E>
2745where
2746 E: Styled,
2747{
2748 fn style(&mut self) -> &mut StyleRefinement {
2749 self.element.style()
2750 }
2751}
2752
2753impl<E> StatefulInteractiveElement for Stateful<E>
2754where
2755 E: Element,
2756 Self: InteractiveElement,
2757{
2758}
2759
2760impl<E> InteractiveElement for Stateful<E>
2761where
2762 E: InteractiveElement,
2763{
2764 fn interactivity(&mut self) -> &mut Interactivity {
2765 self.element.interactivity()
2766 }
2767}
2768
2769impl<E: FocusableElement> FocusableElement for Stateful<E> {}
2770
2771impl<E> Element for Stateful<E>
2772where
2773 E: Element,
2774{
2775 type RequestLayoutState = E::RequestLayoutState;
2776 type PrepaintState = E::PrepaintState;
2777
2778 fn id(&self) -> Option<ElementId> {
2779 self.element.id()
2780 }
2781
2782 fn request_layout(
2783 &mut self,
2784 id: Option<&GlobalElementId>,
2785 window: &mut Window,
2786 cx: &mut App,
2787 ) -> (LayoutId, Self::RequestLayoutState) {
2788 self.element.request_layout(id, window, cx)
2789 }
2790
2791 fn prepaint(
2792 &mut self,
2793 id: Option<&GlobalElementId>,
2794 bounds: Bounds<Pixels>,
2795 state: &mut Self::RequestLayoutState,
2796 window: &mut Window,
2797 cx: &mut App,
2798 ) -> E::PrepaintState {
2799 self.element.prepaint(id, bounds, state, window, cx)
2800 }
2801
2802 fn paint(
2803 &mut self,
2804 id: Option<&GlobalElementId>,
2805 bounds: Bounds<Pixels>,
2806 request_layout: &mut Self::RequestLayoutState,
2807 prepaint: &mut Self::PrepaintState,
2808 window: &mut Window,
2809 cx: &mut App,
2810 ) {
2811 self.element
2812 .paint(id, bounds, request_layout, prepaint, window, cx);
2813 }
2814}
2815
2816impl<E> IntoElement for Stateful<E>
2817where
2818 E: Element,
2819{
2820 type Element = Self;
2821
2822 fn into_element(self) -> Self::Element {
2823 self
2824 }
2825}
2826
2827impl<E> ParentElement for Stateful<E>
2828where
2829 E: ParentElement,
2830{
2831 fn extend(&mut self, elements: impl IntoIterator<Item = AnyElement>) {
2832 self.element.extend(elements)
2833 }
2834}
2835
2836/// Represents an element that can be scrolled *to* in its parent element.
2837///
2838/// Contrary to [ScrollHandle::scroll_to_item], an anchored element does not have to be an immediate child of the parent.
2839#[derive(Clone)]
2840pub struct ScrollAnchor {
2841 handle: ScrollHandle,
2842 last_origin: Rc<RefCell<Point<Pixels>>>,
2843}
2844
2845impl ScrollAnchor {
2846 /// Creates a [ScrollAnchor] associated with a given [ScrollHandle].
2847 pub fn for_handle(handle: ScrollHandle) -> Self {
2848 Self {
2849 handle,
2850 last_origin: Default::default(),
2851 }
2852 }
2853 /// Request scroll to this item on the next frame.
2854 pub fn scroll_to(&self, window: &mut Window, _cx: &mut App) {
2855 let this = self.clone();
2856
2857 window.on_next_frame(move |_, _| {
2858 let viewport_bounds = this.handle.bounds();
2859 let self_bounds = *this.last_origin.borrow();
2860 this.handle.set_offset(viewport_bounds.origin - self_bounds);
2861 });
2862 }
2863}
2864
2865#[derive(Default, Debug)]
2866struct ScrollHandleState {
2867 offset: Rc<RefCell<Point<Pixels>>>,
2868 bounds: Bounds<Pixels>,
2869 child_bounds: Vec<Bounds<Pixels>>,
2870 scroll_to_bottom: bool,
2871 overflow: Point<Overflow>,
2872}
2873
2874/// A handle to the scrollable aspects of an element.
2875/// Used for accessing scroll state, like the current scroll offset,
2876/// and for mutating the scroll state, like scrolling to a specific child.
2877#[derive(Clone, Debug)]
2878pub struct ScrollHandle(Rc<RefCell<ScrollHandleState>>);
2879
2880impl Default for ScrollHandle {
2881 fn default() -> Self {
2882 Self::new()
2883 }
2884}
2885
2886impl ScrollHandle {
2887 /// Construct a new scroll handle.
2888 pub fn new() -> Self {
2889 Self(Rc::default())
2890 }
2891
2892 /// Get the current scroll offset.
2893 pub fn offset(&self) -> Point<Pixels> {
2894 *self.0.borrow().offset.borrow()
2895 }
2896
2897 /// Get the top child that's scrolled into view.
2898 pub fn top_item(&self) -> usize {
2899 let state = self.0.borrow();
2900 let top = state.bounds.top() - state.offset.borrow().y;
2901
2902 match state.child_bounds.binary_search_by(|bounds| {
2903 if top < bounds.top() {
2904 Ordering::Greater
2905 } else if top > bounds.bottom() {
2906 Ordering::Less
2907 } else {
2908 Ordering::Equal
2909 }
2910 }) {
2911 Ok(ix) => ix,
2912 Err(ix) => ix.min(state.child_bounds.len().saturating_sub(1)),
2913 }
2914 }
2915
2916 /// Return the bounds into which this child is painted
2917 pub fn bounds(&self) -> Bounds<Pixels> {
2918 self.0.borrow().bounds
2919 }
2920
2921 /// Set the bounds into which this child is painted
2922 pub(super) fn set_bounds(&self, bounds: Bounds<Pixels>) {
2923 self.0.borrow_mut().bounds = bounds;
2924 }
2925
2926 /// Get the bounds for a specific child.
2927 pub fn bounds_for_item(&self, ix: usize) -> Option<Bounds<Pixels>> {
2928 self.0.borrow().child_bounds.get(ix).cloned()
2929 }
2930
2931 /// scroll_to_item scrolls the minimal amount to ensure that the child is
2932 /// fully visible
2933 pub fn scroll_to_item(&self, ix: usize) {
2934 let state = self.0.borrow();
2935
2936 let Some(bounds) = state.child_bounds.get(ix) else {
2937 return;
2938 };
2939
2940 let mut scroll_offset = state.offset.borrow_mut();
2941
2942 if state.overflow.y == Overflow::Scroll {
2943 if bounds.top() + scroll_offset.y < state.bounds.top() {
2944 scroll_offset.y = state.bounds.top() - bounds.top();
2945 } else if bounds.bottom() + scroll_offset.y > state.bounds.bottom() {
2946 scroll_offset.y = state.bounds.bottom() - bounds.bottom();
2947 }
2948 }
2949
2950 if state.overflow.x == Overflow::Scroll {
2951 if bounds.left() + scroll_offset.x < state.bounds.left() {
2952 scroll_offset.x = state.bounds.left() - bounds.left();
2953 } else if bounds.right() + scroll_offset.x > state.bounds.right() {
2954 scroll_offset.x = state.bounds.right() - bounds.right();
2955 }
2956 }
2957 }
2958
2959 /// Scrolls to the bottom.
2960 pub fn scroll_to_bottom(&self) {
2961 let mut state = self.0.borrow_mut();
2962 state.scroll_to_bottom = true;
2963 }
2964
2965 /// Set the offset explicitly. The offset is the distance from the top left of the
2966 /// parent container to the top left of the first child.
2967 /// As you scroll further down the offset becomes more negative.
2968 pub fn set_offset(&self, mut position: Point<Pixels>) {
2969 let state = self.0.borrow();
2970 *state.offset.borrow_mut() = position;
2971 }
2972
2973 /// Get the logical scroll top, based on a child index and a pixel offset.
2974 pub fn logical_scroll_top(&self) -> (usize, Pixels) {
2975 let ix = self.top_item();
2976 let state = self.0.borrow();
2977
2978 if let Some(child_bounds) = state.child_bounds.get(ix) {
2979 (
2980 ix,
2981 child_bounds.top() + state.offset.borrow().y - state.bounds.top(),
2982 )
2983 } else {
2984 (ix, px(0.))
2985 }
2986 }
2987
2988 /// Get the count of children for scrollable item.
2989 pub fn children_count(&self) -> usize {
2990 self.0.borrow().child_bounds.len()
2991 }
2992}