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 let requested = state.requested_scroll_top.take();
1244
1245 for (ix, child_layout_id) in request_layout.child_layout_ids.iter().enumerate() {
1246 let child_bounds = window.layout_bounds(*child_layout_id);
1247 child_min = child_min.min(&child_bounds.origin);
1248 child_max = child_max.max(&child_bounds.bottom_right());
1249 state.child_bounds.push(child_bounds);
1250
1251 if let Some(requested) = requested.as_ref() {
1252 if requested.0 == ix {
1253 *state.offset.borrow_mut() =
1254 bounds.origin - (child_bounds.origin - point(px(0.), requested.1));
1255 }
1256 }
1257 }
1258 (child_max - child_min).into()
1259 } else {
1260 for child_layout_id in &request_layout.child_layout_ids {
1261 let child_bounds = window.layout_bounds(*child_layout_id);
1262 child_min = child_min.min(&child_bounds.origin);
1263 child_max = child_max.max(&child_bounds.bottom_right());
1264
1265 if has_prepaint_listener {
1266 children_bounds.push(child_bounds);
1267 }
1268 }
1269 (child_max - child_min).into()
1270 };
1271
1272 self.interactivity.prepaint(
1273 global_id,
1274 bounds,
1275 content_size,
1276 window,
1277 cx,
1278 |_style, scroll_offset, hitbox, window, cx| {
1279 window.with_element_offset(scroll_offset, |window| {
1280 for child in &mut self.children {
1281 child.prepaint(window, cx);
1282 }
1283 });
1284
1285 if let Some(listener) = self.prepaint_listener.as_ref() {
1286 listener(children_bounds, window, cx);
1287 }
1288
1289 hitbox
1290 },
1291 )
1292 }
1293
1294 fn paint(
1295 &mut self,
1296 global_id: Option<&GlobalElementId>,
1297 bounds: Bounds<Pixels>,
1298 _request_layout: &mut Self::RequestLayoutState,
1299 hitbox: &mut Option<Hitbox>,
1300 window: &mut Window,
1301 cx: &mut App,
1302 ) {
1303 self.interactivity.paint(
1304 global_id,
1305 bounds,
1306 hitbox.as_ref(),
1307 window,
1308 cx,
1309 |_style, window, cx| {
1310 for child in &mut self.children {
1311 child.paint(window, cx);
1312 }
1313 },
1314 );
1315 }
1316}
1317
1318impl IntoElement for Div {
1319 type Element = Self;
1320
1321 fn into_element(self) -> Self::Element {
1322 self
1323 }
1324}
1325
1326/// The interactivity struct. Powers all of the general-purpose
1327/// interactivity in the `Div` element.
1328#[derive(Default)]
1329pub struct Interactivity {
1330 /// The element ID of the element. In id is required to support a stateful subset of the interactivity such as on_click.
1331 pub element_id: Option<ElementId>,
1332 /// Whether the element was clicked. This will only be present after layout.
1333 pub active: Option<bool>,
1334 /// Whether the element was hovered. This will only be present after paint if an hitbox
1335 /// was created for the interactive element.
1336 pub hovered: Option<bool>,
1337 pub(crate) tooltip_id: Option<TooltipId>,
1338 pub(crate) content_size: Size<Pixels>,
1339 pub(crate) key_context: Option<KeyContext>,
1340 pub(crate) focusable: bool,
1341 pub(crate) tracked_focus_handle: Option<FocusHandle>,
1342 pub(crate) tracked_scroll_handle: Option<ScrollHandle>,
1343 pub(crate) scroll_anchor: Option<ScrollAnchor>,
1344 pub(crate) scroll_offset: Option<Rc<RefCell<Point<Pixels>>>>,
1345 pub(crate) group: Option<SharedString>,
1346 /// The base style of the element, before any modifications are applied
1347 /// by focus, active, etc.
1348 pub base_style: Box<StyleRefinement>,
1349 pub(crate) focus_style: Option<Box<StyleRefinement>>,
1350 pub(crate) in_focus_style: Option<Box<StyleRefinement>>,
1351 pub(crate) hover_style: Option<Box<StyleRefinement>>,
1352 pub(crate) group_hover_style: Option<GroupStyle>,
1353 pub(crate) active_style: Option<Box<StyleRefinement>>,
1354 pub(crate) group_active_style: Option<GroupStyle>,
1355 pub(crate) drag_over_styles: Vec<(
1356 TypeId,
1357 Box<dyn Fn(&dyn Any, &mut Window, &mut App) -> StyleRefinement>,
1358 )>,
1359 pub(crate) group_drag_over_styles: Vec<(TypeId, GroupStyle)>,
1360 pub(crate) mouse_down_listeners: Vec<MouseDownListener>,
1361 pub(crate) mouse_up_listeners: Vec<MouseUpListener>,
1362 pub(crate) mouse_move_listeners: Vec<MouseMoveListener>,
1363 pub(crate) scroll_wheel_listeners: Vec<ScrollWheelListener>,
1364 pub(crate) key_down_listeners: Vec<KeyDownListener>,
1365 pub(crate) key_up_listeners: Vec<KeyUpListener>,
1366 pub(crate) modifiers_changed_listeners: Vec<ModifiersChangedListener>,
1367 pub(crate) action_listeners: Vec<(TypeId, ActionListener)>,
1368 pub(crate) drop_listeners: Vec<(TypeId, DropListener)>,
1369 pub(crate) can_drop_predicate: Option<CanDropPredicate>,
1370 pub(crate) click_listeners: Vec<ClickListener>,
1371 pub(crate) drag_listener: Option<(Arc<dyn Any>, DragListener)>,
1372 pub(crate) hover_listener: Option<Box<dyn Fn(&bool, &mut Window, &mut App)>>,
1373 pub(crate) tooltip_builder: Option<TooltipBuilder>,
1374 pub(crate) occlude_mouse: bool,
1375
1376 #[cfg(debug_assertions)]
1377 pub(crate) location: Option<core::panic::Location<'static>>,
1378
1379 #[cfg(any(test, feature = "test-support"))]
1380 pub(crate) debug_selector: Option<String>,
1381}
1382
1383impl Interactivity {
1384 /// Layout this element according to this interactivity state's configured styles
1385 pub fn request_layout(
1386 &mut self,
1387 global_id: Option<&GlobalElementId>,
1388 window: &mut Window,
1389 cx: &mut App,
1390 f: impl FnOnce(Style, &mut Window, &mut App) -> LayoutId,
1391 ) -> LayoutId {
1392 window.with_optional_element_state::<InteractiveElementState, _>(
1393 global_id,
1394 |element_state, window| {
1395 let mut element_state =
1396 element_state.map(|element_state| element_state.unwrap_or_default());
1397
1398 if let Some(element_state) = element_state.as_ref() {
1399 if cx.has_active_drag() {
1400 if let Some(pending_mouse_down) = element_state.pending_mouse_down.as_ref()
1401 {
1402 *pending_mouse_down.borrow_mut() = None;
1403 }
1404 if let Some(clicked_state) = element_state.clicked_state.as_ref() {
1405 *clicked_state.borrow_mut() = ElementClickedState::default();
1406 }
1407 }
1408 }
1409
1410 // Ensure we store a focus handle in our element state if we're focusable.
1411 // If there's an explicit focus handle we're tracking, use that. Otherwise
1412 // create a new handle and store it in the element state, which lives for as
1413 // as frames contain an element with this id.
1414 if self.focusable && self.tracked_focus_handle.is_none() {
1415 if let Some(element_state) = element_state.as_mut() {
1416 self.tracked_focus_handle = Some(
1417 element_state
1418 .focus_handle
1419 .get_or_insert_with(|| cx.focus_handle())
1420 .clone(),
1421 );
1422 }
1423 }
1424
1425 if let Some(scroll_handle) = self.tracked_scroll_handle.as_ref() {
1426 self.scroll_offset = Some(scroll_handle.0.borrow().offset.clone());
1427 } else if self.base_style.overflow.x == Some(Overflow::Scroll)
1428 || self.base_style.overflow.y == Some(Overflow::Scroll)
1429 {
1430 if let Some(element_state) = element_state.as_mut() {
1431 self.scroll_offset = Some(
1432 element_state
1433 .scroll_offset
1434 .get_or_insert_with(Rc::default)
1435 .clone(),
1436 );
1437 }
1438 }
1439
1440 let style = self.compute_style_internal(None, element_state.as_mut(), window, cx);
1441 let layout_id = f(style, window, cx);
1442 (layout_id, element_state)
1443 },
1444 )
1445 }
1446
1447 /// Commit the bounds of this element according to this interactivity state's configured styles.
1448 pub fn prepaint<R>(
1449 &mut self,
1450 global_id: Option<&GlobalElementId>,
1451 bounds: Bounds<Pixels>,
1452 content_size: Size<Pixels>,
1453 window: &mut Window,
1454 cx: &mut App,
1455 f: impl FnOnce(&Style, Point<Pixels>, Option<Hitbox>, &mut Window, &mut App) -> R,
1456 ) -> R {
1457 self.content_size = content_size;
1458 if let Some(focus_handle) = self.tracked_focus_handle.as_ref() {
1459 window.set_focus_handle(focus_handle, cx);
1460 }
1461 window.with_optional_element_state::<InteractiveElementState, _>(
1462 global_id,
1463 |element_state, window| {
1464 let mut element_state =
1465 element_state.map(|element_state| element_state.unwrap_or_default());
1466 let style = self.compute_style_internal(None, element_state.as_mut(), window, cx);
1467
1468 if let Some(element_state) = element_state.as_mut() {
1469 if let Some(clicked_state) = element_state.clicked_state.as_ref() {
1470 let clicked_state = clicked_state.borrow();
1471 self.active = Some(clicked_state.element);
1472 }
1473 if let Some(active_tooltip) = element_state.active_tooltip.as_ref() {
1474 if self.tooltip_builder.is_some() {
1475 self.tooltip_id = set_tooltip_on_window(active_tooltip, window);
1476 } else {
1477 // If there is no longer a tooltip builder, remove the active tooltip.
1478 element_state.active_tooltip.take();
1479 }
1480 }
1481 }
1482
1483 window.with_text_style(style.text_style().cloned(), |window| {
1484 window.with_content_mask(
1485 style.overflow_mask(bounds, window.rem_size()),
1486 |window| {
1487 let hitbox = if self.should_insert_hitbox(&style) {
1488 Some(window.insert_hitbox(bounds, self.occlude_mouse))
1489 } else {
1490 None
1491 };
1492
1493 let scroll_offset =
1494 self.clamp_scroll_position(bounds, &style, window, cx);
1495 let result = f(&style, scroll_offset, hitbox, window, cx);
1496 (result, element_state)
1497 },
1498 )
1499 })
1500 },
1501 )
1502 }
1503
1504 fn should_insert_hitbox(&self, style: &Style) -> bool {
1505 self.occlude_mouse
1506 || style.mouse_cursor.is_some()
1507 || self.group.is_some()
1508 || self.scroll_offset.is_some()
1509 || self.tracked_focus_handle.is_some()
1510 || self.hover_style.is_some()
1511 || self.group_hover_style.is_some()
1512 || self.hover_listener.is_some()
1513 || !self.mouse_up_listeners.is_empty()
1514 || !self.mouse_down_listeners.is_empty()
1515 || !self.mouse_move_listeners.is_empty()
1516 || !self.click_listeners.is_empty()
1517 || !self.scroll_wheel_listeners.is_empty()
1518 || self.drag_listener.is_some()
1519 || !self.drop_listeners.is_empty()
1520 || self.tooltip_builder.is_some()
1521 }
1522
1523 fn clamp_scroll_position(
1524 &self,
1525 bounds: Bounds<Pixels>,
1526 style: &Style,
1527 window: &mut Window,
1528 _cx: &mut App,
1529 ) -> Point<Pixels> {
1530 if let Some(scroll_offset) = self.scroll_offset.as_ref() {
1531 if let Some(scroll_handle) = &self.tracked_scroll_handle {
1532 scroll_handle.0.borrow_mut().overflow = style.overflow;
1533 }
1534
1535 let rem_size = window.rem_size();
1536 let padding_size = size(
1537 style
1538 .padding
1539 .left
1540 .to_pixels(bounds.size.width.into(), rem_size)
1541 + style
1542 .padding
1543 .right
1544 .to_pixels(bounds.size.width.into(), rem_size),
1545 style
1546 .padding
1547 .top
1548 .to_pixels(bounds.size.height.into(), rem_size)
1549 + style
1550 .padding
1551 .bottom
1552 .to_pixels(bounds.size.height.into(), rem_size),
1553 );
1554 let scroll_max = (self.content_size + padding_size - bounds.size).max(&Size::default());
1555 // Clamp scroll offset in case scroll max is smaller now (e.g., if children
1556 // were removed or the bounds became larger).
1557 let mut scroll_offset = scroll_offset.borrow_mut();
1558 scroll_offset.x = scroll_offset.x.clamp(-scroll_max.width, px(0.));
1559 scroll_offset.y = scroll_offset.y.clamp(-scroll_max.height, px(0.));
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 window.on_mouse_event({
1712 let hitbox = hitbox.clone();
1713 move |_: &MouseMoveEvent, phase, window, _| {
1714 if phase == DispatchPhase::Capture {
1715 let hovered = hitbox.is_hovered(window);
1716 if hovered != was_hovered {
1717 window.refresh();
1718 }
1719 }
1720 }
1721 });
1722
1723 window.on_mouse_event({
1724 let hitbox = hitbox.clone();
1725 let location = self.location.unwrap();
1726 move |e: &crate::MouseDownEvent, phase, window, cx| {
1727 if text_bounds.contains(&e.position)
1728 && phase.capture()
1729 && hitbox.is_hovered(window)
1730 {
1731 cx.stop_propagation();
1732 let Ok(dir) = std::env::current_dir() else {
1733 return;
1734 };
1735
1736 eprintln!(
1737 "This element was created at:\n{}:{}:{}",
1738 dir.join(location.file()).to_string_lossy(),
1739 location.line(),
1740 location.column()
1741 );
1742 }
1743 }
1744 });
1745 window.paint_quad(crate::outline(
1746 crate::Bounds {
1747 origin: hitbox.origin
1748 + crate::point(crate::px(0.), FONT_SIZE - px(2.)),
1749 size: crate::Size {
1750 width: text_bounds.size.width,
1751 height: crate::px(1.),
1752 },
1753 },
1754 crate::red(),
1755 ))
1756 }
1757 }
1758 };
1759
1760 window.with_text_style(
1761 Some(crate::TextStyleRefinement {
1762 color: Some(crate::red()),
1763 line_height: Some(FONT_SIZE.into()),
1764 background_color: Some(crate::white()),
1765 ..Default::default()
1766 }),
1767 render_debug_text,
1768 )
1769 }
1770 }
1771
1772 fn paint_mouse_listeners(
1773 &mut self,
1774 hitbox: &Hitbox,
1775 element_state: Option<&mut InteractiveElementState>,
1776 window: &mut Window,
1777 cx: &mut App,
1778 ) {
1779 // If this element can be focused, register a mouse down listener
1780 // that will automatically transfer focus when hitting the element.
1781 // This behavior can be suppressed by using `cx.prevent_default()`.
1782 if let Some(focus_handle) = self.tracked_focus_handle.clone() {
1783 let hitbox = hitbox.clone();
1784 window.on_mouse_event(move |_: &MouseDownEvent, phase, window, _| {
1785 if phase == DispatchPhase::Bubble
1786 && hitbox.is_hovered(window)
1787 && !window.default_prevented()
1788 {
1789 window.focus(&focus_handle);
1790 // If there is a parent that is also focusable, prevent it
1791 // from transferring focus because we already did so.
1792 window.prevent_default();
1793 }
1794 });
1795 }
1796
1797 for listener in self.mouse_down_listeners.drain(..) {
1798 let hitbox = hitbox.clone();
1799 window.on_mouse_event(move |event: &MouseDownEvent, phase, window, cx| {
1800 listener(event, phase, &hitbox, window, cx);
1801 })
1802 }
1803
1804 for listener in self.mouse_up_listeners.drain(..) {
1805 let hitbox = hitbox.clone();
1806 window.on_mouse_event(move |event: &MouseUpEvent, phase, window, cx| {
1807 listener(event, phase, &hitbox, window, cx);
1808 })
1809 }
1810
1811 for listener in self.mouse_move_listeners.drain(..) {
1812 let hitbox = hitbox.clone();
1813 window.on_mouse_event(move |event: &MouseMoveEvent, phase, window, cx| {
1814 listener(event, phase, &hitbox, window, cx);
1815 })
1816 }
1817
1818 for listener in self.scroll_wheel_listeners.drain(..) {
1819 let hitbox = hitbox.clone();
1820 window.on_mouse_event(move |event: &ScrollWheelEvent, phase, window, cx| {
1821 listener(event, phase, &hitbox, window, cx);
1822 })
1823 }
1824
1825 if self.hover_style.is_some()
1826 || self.base_style.mouse_cursor.is_some()
1827 || cx.active_drag.is_some() && !self.drag_over_styles.is_empty()
1828 {
1829 let hitbox = hitbox.clone();
1830 let was_hovered = hitbox.is_hovered(window);
1831 window.on_mouse_event(move |_: &MouseMoveEvent, phase, window, _cx| {
1832 let hovered = hitbox.is_hovered(window);
1833 if phase == DispatchPhase::Capture && hovered != was_hovered {
1834 window.refresh();
1835 }
1836 });
1837 }
1838
1839 let mut drag_listener = mem::take(&mut self.drag_listener);
1840 let drop_listeners = mem::take(&mut self.drop_listeners);
1841 let click_listeners = mem::take(&mut self.click_listeners);
1842 let can_drop_predicate = mem::take(&mut self.can_drop_predicate);
1843
1844 if !drop_listeners.is_empty() {
1845 let hitbox = hitbox.clone();
1846 window.on_mouse_event({
1847 move |_: &MouseUpEvent, phase, window, cx| {
1848 if let Some(drag) = &cx.active_drag {
1849 if phase == DispatchPhase::Bubble && hitbox.is_hovered(window) {
1850 let drag_state_type = drag.value.as_ref().type_id();
1851 for (drop_state_type, listener) in &drop_listeners {
1852 if *drop_state_type == drag_state_type {
1853 let drag = cx
1854 .active_drag
1855 .take()
1856 .expect("checked for type drag state type above");
1857
1858 let mut can_drop = true;
1859 if let Some(predicate) = &can_drop_predicate {
1860 can_drop = predicate(drag.value.as_ref(), window, cx);
1861 }
1862
1863 if can_drop {
1864 listener(drag.value.as_ref(), window, cx);
1865 window.refresh();
1866 cx.stop_propagation();
1867 }
1868 }
1869 }
1870 }
1871 }
1872 }
1873 });
1874 }
1875
1876 if let Some(element_state) = element_state {
1877 if !click_listeners.is_empty() || drag_listener.is_some() {
1878 let pending_mouse_down = element_state
1879 .pending_mouse_down
1880 .get_or_insert_with(Default::default)
1881 .clone();
1882
1883 let clicked_state = element_state
1884 .clicked_state
1885 .get_or_insert_with(Default::default)
1886 .clone();
1887
1888 window.on_mouse_event({
1889 let pending_mouse_down = pending_mouse_down.clone();
1890 let hitbox = hitbox.clone();
1891 move |event: &MouseDownEvent, phase, window, _cx| {
1892 if phase == DispatchPhase::Bubble
1893 && event.button == MouseButton::Left
1894 && hitbox.is_hovered(window)
1895 {
1896 *pending_mouse_down.borrow_mut() = Some(event.clone());
1897 window.refresh();
1898 }
1899 }
1900 });
1901
1902 window.on_mouse_event({
1903 let pending_mouse_down = pending_mouse_down.clone();
1904 let hitbox = hitbox.clone();
1905 move |event: &MouseMoveEvent, phase, window, cx| {
1906 if phase == DispatchPhase::Capture {
1907 return;
1908 }
1909
1910 let mut pending_mouse_down = pending_mouse_down.borrow_mut();
1911 if let Some(mouse_down) = pending_mouse_down.clone() {
1912 if !cx.has_active_drag()
1913 && (event.position - mouse_down.position).magnitude()
1914 > DRAG_THRESHOLD
1915 {
1916 if let Some((drag_value, drag_listener)) = drag_listener.take() {
1917 *clicked_state.borrow_mut() = ElementClickedState::default();
1918 let cursor_offset = event.position - hitbox.origin;
1919 let drag = (drag_listener)(
1920 drag_value.as_ref(),
1921 cursor_offset,
1922 window,
1923 cx,
1924 );
1925 cx.active_drag = Some(AnyDrag {
1926 view: drag,
1927 value: drag_value,
1928 cursor_offset,
1929 });
1930 pending_mouse_down.take();
1931 window.refresh();
1932 cx.stop_propagation();
1933 }
1934 }
1935 }
1936 }
1937 });
1938
1939 window.on_mouse_event({
1940 let mut captured_mouse_down = None;
1941 let hitbox = hitbox.clone();
1942 move |event: &MouseUpEvent, phase, window, cx| match phase {
1943 // Clear the pending mouse down during the capture phase,
1944 // so that it happens even if another event handler stops
1945 // propagation.
1946 DispatchPhase::Capture => {
1947 let mut pending_mouse_down = pending_mouse_down.borrow_mut();
1948 if pending_mouse_down.is_some() && hitbox.is_hovered(window) {
1949 captured_mouse_down = pending_mouse_down.take();
1950 window.refresh();
1951 }
1952 }
1953 // Fire click handlers during the bubble phase.
1954 DispatchPhase::Bubble => {
1955 if let Some(mouse_down) = captured_mouse_down.take() {
1956 let mouse_click = ClickEvent {
1957 down: mouse_down,
1958 up: event.clone(),
1959 };
1960 for listener in &click_listeners {
1961 listener(&mouse_click, window, cx);
1962 }
1963 }
1964 }
1965 }
1966 });
1967 }
1968
1969 if let Some(hover_listener) = self.hover_listener.take() {
1970 let hitbox = hitbox.clone();
1971 let was_hovered = element_state
1972 .hover_state
1973 .get_or_insert_with(Default::default)
1974 .clone();
1975 let has_mouse_down = element_state
1976 .pending_mouse_down
1977 .get_or_insert_with(Default::default)
1978 .clone();
1979
1980 window.on_mouse_event(move |_: &MouseMoveEvent, phase, window, cx| {
1981 if phase != DispatchPhase::Bubble {
1982 return;
1983 }
1984 let is_hovered = has_mouse_down.borrow().is_none()
1985 && !cx.has_active_drag()
1986 && hitbox.is_hovered(window);
1987 let mut was_hovered = was_hovered.borrow_mut();
1988
1989 if is_hovered != *was_hovered {
1990 *was_hovered = is_hovered;
1991 drop(was_hovered);
1992
1993 hover_listener(&is_hovered, window, cx);
1994 }
1995 });
1996 }
1997
1998 if let Some(tooltip_builder) = self.tooltip_builder.take() {
1999 let active_tooltip = element_state
2000 .active_tooltip
2001 .get_or_insert_with(Default::default)
2002 .clone();
2003 let pending_mouse_down = element_state
2004 .pending_mouse_down
2005 .get_or_insert_with(Default::default)
2006 .clone();
2007
2008 let tooltip_is_hoverable = tooltip_builder.hoverable;
2009 let build_tooltip = Rc::new(move |window: &mut Window, cx: &mut App| {
2010 Some(((tooltip_builder.build)(window, cx), tooltip_is_hoverable))
2011 });
2012 // Use bounds instead of testing hitbox since this is called during prepaint.
2013 let check_is_hovered_during_prepaint = Rc::new({
2014 let pending_mouse_down = pending_mouse_down.clone();
2015 let source_bounds = hitbox.bounds;
2016 move |window: &Window| {
2017 pending_mouse_down.borrow().is_none()
2018 && source_bounds.contains(&window.mouse_position())
2019 }
2020 });
2021 let check_is_hovered = Rc::new({
2022 let hitbox = hitbox.clone();
2023 move |window: &Window| {
2024 pending_mouse_down.borrow().is_none() && hitbox.is_hovered(window)
2025 }
2026 });
2027 register_tooltip_mouse_handlers(
2028 &active_tooltip,
2029 self.tooltip_id,
2030 build_tooltip,
2031 check_is_hovered,
2032 check_is_hovered_during_prepaint,
2033 window,
2034 );
2035 }
2036
2037 let active_state = element_state
2038 .clicked_state
2039 .get_or_insert_with(Default::default)
2040 .clone();
2041 if active_state.borrow().is_clicked() {
2042 window.on_mouse_event(move |_: &MouseUpEvent, phase, window, _cx| {
2043 if phase == DispatchPhase::Capture {
2044 *active_state.borrow_mut() = ElementClickedState::default();
2045 window.refresh();
2046 }
2047 });
2048 } else {
2049 let active_group_hitbox = self
2050 .group_active_style
2051 .as_ref()
2052 .and_then(|group_active| GroupHitboxes::get(&group_active.group, cx));
2053 let hitbox = hitbox.clone();
2054 window.on_mouse_event(move |_: &MouseDownEvent, phase, window, _cx| {
2055 if phase == DispatchPhase::Bubble && !window.default_prevented() {
2056 let group_hovered = active_group_hitbox
2057 .map_or(false, |group_hitbox_id| group_hitbox_id.is_hovered(window));
2058 let element_hovered = hitbox.is_hovered(window);
2059 if group_hovered || element_hovered {
2060 *active_state.borrow_mut() = ElementClickedState {
2061 group: group_hovered,
2062 element: element_hovered,
2063 };
2064 window.refresh();
2065 }
2066 }
2067 });
2068 }
2069 }
2070 }
2071
2072 fn paint_keyboard_listeners(&mut self, window: &mut Window, _cx: &mut App) {
2073 let key_down_listeners = mem::take(&mut self.key_down_listeners);
2074 let key_up_listeners = mem::take(&mut self.key_up_listeners);
2075 let modifiers_changed_listeners = mem::take(&mut self.modifiers_changed_listeners);
2076 let action_listeners = mem::take(&mut self.action_listeners);
2077 if let Some(context) = self.key_context.clone() {
2078 window.set_key_context(context);
2079 }
2080
2081 for listener in key_down_listeners {
2082 window.on_key_event(move |event: &KeyDownEvent, phase, window, cx| {
2083 listener(event, phase, window, cx);
2084 })
2085 }
2086
2087 for listener in key_up_listeners {
2088 window.on_key_event(move |event: &KeyUpEvent, phase, window, cx| {
2089 listener(event, phase, window, cx);
2090 })
2091 }
2092
2093 for listener in modifiers_changed_listeners {
2094 window.on_modifiers_changed(move |event: &ModifiersChangedEvent, window, cx| {
2095 listener(event, window, cx);
2096 })
2097 }
2098
2099 for (action_type, listener) in action_listeners {
2100 window.on_action(action_type, listener)
2101 }
2102 }
2103
2104 fn paint_hover_group_handler(&self, window: &mut Window, cx: &mut App) {
2105 let group_hitbox = self
2106 .group_hover_style
2107 .as_ref()
2108 .and_then(|group_hover| GroupHitboxes::get(&group_hover.group, cx));
2109
2110 if let Some(group_hitbox) = group_hitbox {
2111 let was_hovered = group_hitbox.is_hovered(window);
2112 window.on_mouse_event(move |_: &MouseMoveEvent, phase, window, _cx| {
2113 let hovered = group_hitbox.is_hovered(window);
2114 if phase == DispatchPhase::Capture && hovered != was_hovered {
2115 window.refresh();
2116 }
2117 });
2118 }
2119 }
2120
2121 fn paint_scroll_listener(
2122 &self,
2123 hitbox: &Hitbox,
2124 style: &Style,
2125 window: &mut Window,
2126 _cx: &mut App,
2127 ) {
2128 if let Some(scroll_offset) = self.scroll_offset.clone() {
2129 let overflow = style.overflow;
2130 let allow_concurrent_scroll = style.allow_concurrent_scroll;
2131 let restrict_scroll_to_axis = style.restrict_scroll_to_axis;
2132 let line_height = window.line_height();
2133 let hitbox = hitbox.clone();
2134 window.on_mouse_event(move |event: &ScrollWheelEvent, phase, window, cx| {
2135 if phase == DispatchPhase::Bubble && hitbox.is_hovered(window) {
2136 let mut scroll_offset = scroll_offset.borrow_mut();
2137 let old_scroll_offset = *scroll_offset;
2138 let delta = event.delta.pixel_delta(line_height);
2139
2140 let mut delta_x = Pixels::ZERO;
2141 if overflow.x == Overflow::Scroll {
2142 if !delta.x.is_zero() {
2143 delta_x = delta.x;
2144 } else if !restrict_scroll_to_axis && overflow.y != Overflow::Scroll {
2145 delta_x = delta.y;
2146 }
2147 }
2148 let mut delta_y = Pixels::ZERO;
2149 if overflow.y == Overflow::Scroll {
2150 if !delta.y.is_zero() {
2151 delta_y = delta.y;
2152 } else if !restrict_scroll_to_axis && overflow.x != Overflow::Scroll {
2153 delta_y = delta.x;
2154 }
2155 }
2156 if !allow_concurrent_scroll && !delta_x.is_zero() && !delta_y.is_zero() {
2157 if delta_x.abs() > delta_y.abs() {
2158 delta_y = Pixels::ZERO;
2159 } else {
2160 delta_x = Pixels::ZERO;
2161 }
2162 }
2163 scroll_offset.y += delta_y;
2164 scroll_offset.x += delta_x;
2165 cx.stop_propagation();
2166 if *scroll_offset != old_scroll_offset {
2167 window.refresh();
2168 }
2169 }
2170 });
2171 }
2172 }
2173
2174 /// Compute the visual style for this element, based on the current bounds and the element's state.
2175 pub fn compute_style(
2176 &self,
2177 global_id: Option<&GlobalElementId>,
2178 hitbox: Option<&Hitbox>,
2179 window: &mut Window,
2180 cx: &mut App,
2181 ) -> Style {
2182 window.with_optional_element_state(global_id, |element_state, window| {
2183 let mut element_state =
2184 element_state.map(|element_state| element_state.unwrap_or_default());
2185 let style = self.compute_style_internal(hitbox, element_state.as_mut(), window, cx);
2186 (style, element_state)
2187 })
2188 }
2189
2190 /// Called from internal methods that have already called with_element_state.
2191 fn compute_style_internal(
2192 &self,
2193 hitbox: Option<&Hitbox>,
2194 element_state: Option<&mut InteractiveElementState>,
2195 window: &mut Window,
2196 cx: &mut App,
2197 ) -> Style {
2198 let mut style = Style::default();
2199 style.refine(&self.base_style);
2200
2201 if let Some(focus_handle) = self.tracked_focus_handle.as_ref() {
2202 if let Some(in_focus_style) = self.in_focus_style.as_ref() {
2203 if focus_handle.within_focused(window, cx) {
2204 style.refine(in_focus_style);
2205 }
2206 }
2207
2208 if let Some(focus_style) = self.focus_style.as_ref() {
2209 if focus_handle.is_focused(window) {
2210 style.refine(focus_style);
2211 }
2212 }
2213 }
2214
2215 if let Some(hitbox) = hitbox {
2216 if !cx.has_active_drag() {
2217 if let Some(group_hover) = self.group_hover_style.as_ref() {
2218 if let Some(group_hitbox_id) = GroupHitboxes::get(&group_hover.group, cx) {
2219 if group_hitbox_id.is_hovered(window) {
2220 style.refine(&group_hover.style);
2221 }
2222 }
2223 }
2224
2225 if let Some(hover_style) = self.hover_style.as_ref() {
2226 if hitbox.is_hovered(window) {
2227 style.refine(hover_style);
2228 }
2229 }
2230 }
2231
2232 if let Some(drag) = cx.active_drag.take() {
2233 let mut can_drop = true;
2234 if let Some(can_drop_predicate) = &self.can_drop_predicate {
2235 can_drop = can_drop_predicate(drag.value.as_ref(), window, cx);
2236 }
2237
2238 if can_drop {
2239 for (state_type, group_drag_style) in &self.group_drag_over_styles {
2240 if let Some(group_hitbox_id) =
2241 GroupHitboxes::get(&group_drag_style.group, cx)
2242 {
2243 if *state_type == drag.value.as_ref().type_id()
2244 && group_hitbox_id.is_hovered(window)
2245 {
2246 style.refine(&group_drag_style.style);
2247 }
2248 }
2249 }
2250
2251 for (state_type, build_drag_over_style) in &self.drag_over_styles {
2252 if *state_type == drag.value.as_ref().type_id() && hitbox.is_hovered(window)
2253 {
2254 style.refine(&build_drag_over_style(drag.value.as_ref(), window, cx));
2255 }
2256 }
2257 }
2258
2259 cx.active_drag = Some(drag);
2260 }
2261 }
2262
2263 if let Some(element_state) = element_state {
2264 let clicked_state = element_state
2265 .clicked_state
2266 .get_or_insert_with(Default::default)
2267 .borrow();
2268 if clicked_state.group {
2269 if let Some(group) = self.group_active_style.as_ref() {
2270 style.refine(&group.style)
2271 }
2272 }
2273
2274 if let Some(active_style) = self.active_style.as_ref() {
2275 if clicked_state.element {
2276 style.refine(active_style)
2277 }
2278 }
2279 }
2280
2281 style
2282 }
2283}
2284
2285/// The per-frame state of an interactive element. Used for tracking stateful interactions like clicks
2286/// and scroll offsets.
2287#[derive(Default)]
2288pub struct InteractiveElementState {
2289 pub(crate) focus_handle: Option<FocusHandle>,
2290 pub(crate) clicked_state: Option<Rc<RefCell<ElementClickedState>>>,
2291 pub(crate) hover_state: Option<Rc<RefCell<bool>>>,
2292 pub(crate) pending_mouse_down: Option<Rc<RefCell<Option<MouseDownEvent>>>>,
2293 pub(crate) scroll_offset: Option<Rc<RefCell<Point<Pixels>>>>,
2294 pub(crate) active_tooltip: Option<Rc<RefCell<Option<ActiveTooltip>>>>,
2295}
2296
2297/// Whether or not the element or a group that contains it is clicked by the mouse.
2298#[derive(Copy, Clone, Default, Eq, PartialEq)]
2299pub struct ElementClickedState {
2300 /// True if this element's group has been clicked, false otherwise
2301 pub group: bool,
2302
2303 /// True if this element has been clicked, false otherwise
2304 pub element: bool,
2305}
2306
2307impl ElementClickedState {
2308 fn is_clicked(&self) -> bool {
2309 self.group || self.element
2310 }
2311}
2312
2313pub(crate) enum ActiveTooltip {
2314 /// Currently delaying before showing the tooltip.
2315 WaitingForShow { _task: Task<()> },
2316 /// Tooltip is visible, element was hovered or for hoverable tooltips, the tooltip was hovered.
2317 Visible {
2318 tooltip: AnyTooltip,
2319 is_hoverable: bool,
2320 },
2321 /// Tooltip is visible and hoverable, but the mouse is no longer hovering. Currently delaying
2322 /// before hiding it.
2323 WaitingForHide {
2324 tooltip: AnyTooltip,
2325 _task: Task<()>,
2326 },
2327}
2328
2329pub(crate) fn clear_active_tooltip(
2330 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2331 window: &mut Window,
2332) {
2333 match active_tooltip.borrow_mut().take() {
2334 None => {}
2335 Some(ActiveTooltip::WaitingForShow { .. }) => {}
2336 Some(ActiveTooltip::Visible { .. }) => window.refresh(),
2337 Some(ActiveTooltip::WaitingForHide { .. }) => window.refresh(),
2338 }
2339}
2340
2341pub(crate) fn clear_active_tooltip_if_not_hoverable(
2342 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2343 window: &mut Window,
2344) {
2345 let should_clear = match active_tooltip.borrow().as_ref() {
2346 None => false,
2347 Some(ActiveTooltip::WaitingForShow { .. }) => false,
2348 Some(ActiveTooltip::Visible { is_hoverable, .. }) => !is_hoverable,
2349 Some(ActiveTooltip::WaitingForHide { .. }) => false,
2350 };
2351 if should_clear {
2352 active_tooltip.borrow_mut().take();
2353 window.refresh();
2354 }
2355}
2356
2357pub(crate) fn set_tooltip_on_window(
2358 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2359 window: &mut Window,
2360) -> Option<TooltipId> {
2361 let tooltip = match active_tooltip.borrow().as_ref() {
2362 None => return None,
2363 Some(ActiveTooltip::WaitingForShow { .. }) => return None,
2364 Some(ActiveTooltip::Visible { tooltip, .. }) => tooltip.clone(),
2365 Some(ActiveTooltip::WaitingForHide { tooltip, .. }) => tooltip.clone(),
2366 };
2367 Some(window.set_tooltip(tooltip))
2368}
2369
2370pub(crate) fn register_tooltip_mouse_handlers(
2371 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2372 tooltip_id: Option<TooltipId>,
2373 build_tooltip: Rc<dyn Fn(&mut Window, &mut App) -> Option<(AnyView, bool)>>,
2374 check_is_hovered: Rc<dyn Fn(&Window) -> bool>,
2375 check_is_hovered_during_prepaint: Rc<dyn Fn(&Window) -> bool>,
2376 window: &mut Window,
2377) {
2378 window.on_mouse_event({
2379 let active_tooltip = active_tooltip.clone();
2380 let build_tooltip = build_tooltip.clone();
2381 let check_is_hovered = check_is_hovered.clone();
2382 move |_: &MouseMoveEvent, phase, window, cx| {
2383 handle_tooltip_mouse_move(
2384 &active_tooltip,
2385 &build_tooltip,
2386 &check_is_hovered,
2387 &check_is_hovered_during_prepaint,
2388 phase,
2389 window,
2390 cx,
2391 )
2392 }
2393 });
2394
2395 window.on_mouse_event({
2396 let active_tooltip = active_tooltip.clone();
2397 move |_: &MouseDownEvent, _phase, window: &mut Window, _cx| {
2398 if !tooltip_id.map_or(false, |tooltip_id| tooltip_id.is_hovered(window)) {
2399 clear_active_tooltip_if_not_hoverable(&active_tooltip, window);
2400 }
2401 }
2402 });
2403
2404 window.on_mouse_event({
2405 let active_tooltip = active_tooltip.clone();
2406 move |_: &ScrollWheelEvent, _phase, window: &mut Window, _cx| {
2407 if !tooltip_id.map_or(false, |tooltip_id| tooltip_id.is_hovered(window)) {
2408 clear_active_tooltip_if_not_hoverable(&active_tooltip, window);
2409 }
2410 }
2411 });
2412}
2413
2414/// Handles displaying tooltips when an element is hovered.
2415///
2416/// The mouse hovering logic also relies on being called from window prepaint in order to handle the
2417/// case where the element the tooltip is on is not rendered - in that case its mouse listeners are
2418/// also not registered. During window prepaint, the hitbox information is not available, so
2419/// `check_is_hovered_during_prepaint` is used which bases the check off of the absolute bounds of
2420/// the element.
2421///
2422/// TODO: There's a minor bug due to the use of absolute bounds while checking during prepaint - it
2423/// does not know if the hitbox is occluded. In the case where a tooltip gets displayed and then
2424/// gets occluded after display, it will stick around until the mouse exits the hover bounds.
2425fn handle_tooltip_mouse_move(
2426 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2427 build_tooltip: &Rc<dyn Fn(&mut Window, &mut App) -> Option<(AnyView, bool)>>,
2428 check_is_hovered: &Rc<dyn Fn(&Window) -> bool>,
2429 check_is_hovered_during_prepaint: &Rc<dyn Fn(&Window) -> bool>,
2430 phase: DispatchPhase,
2431 window: &mut Window,
2432 cx: &mut App,
2433) {
2434 // Separates logic for what mutation should occur from applying it, to avoid overlapping
2435 // RefCell borrows.
2436 enum Action {
2437 None,
2438 CancelShow,
2439 ScheduleShow,
2440 }
2441
2442 let action = match active_tooltip.borrow().as_ref() {
2443 None => {
2444 let is_hovered = check_is_hovered(window);
2445 if is_hovered && phase.bubble() {
2446 Action::ScheduleShow
2447 } else {
2448 Action::None
2449 }
2450 }
2451 Some(ActiveTooltip::WaitingForShow { .. }) => {
2452 let is_hovered = check_is_hovered(window);
2453 if is_hovered {
2454 Action::None
2455 } else {
2456 Action::CancelShow
2457 }
2458 }
2459 // These are handled in check_visible_and_update.
2460 Some(ActiveTooltip::Visible { .. }) | Some(ActiveTooltip::WaitingForHide { .. }) => {
2461 Action::None
2462 }
2463 };
2464
2465 match action {
2466 Action::None => {}
2467 Action::CancelShow => {
2468 // Cancel waiting to show tooltip when it is no longer hovered.
2469 active_tooltip.borrow_mut().take();
2470 }
2471 Action::ScheduleShow => {
2472 let delayed_show_task = window.spawn(cx, {
2473 let active_tooltip = active_tooltip.clone();
2474 let build_tooltip = build_tooltip.clone();
2475 let check_is_hovered_during_prepaint = check_is_hovered_during_prepaint.clone();
2476 move |mut cx| async move {
2477 cx.background_executor().timer(TOOLTIP_SHOW_DELAY).await;
2478 cx.update(|window, cx| {
2479 let new_tooltip =
2480 build_tooltip(window, cx).map(|(view, tooltip_is_hoverable)| {
2481 let active_tooltip = active_tooltip.clone();
2482 ActiveTooltip::Visible {
2483 tooltip: AnyTooltip {
2484 view,
2485 mouse_position: window.mouse_position(),
2486 check_visible_and_update: Rc::new(
2487 move |tooltip_bounds, window, cx| {
2488 handle_tooltip_check_visible_and_update(
2489 &active_tooltip,
2490 tooltip_is_hoverable,
2491 &check_is_hovered_during_prepaint,
2492 tooltip_bounds,
2493 window,
2494 cx,
2495 )
2496 },
2497 ),
2498 },
2499 is_hoverable: tooltip_is_hoverable,
2500 }
2501 });
2502 *active_tooltip.borrow_mut() = new_tooltip;
2503 window.refresh();
2504 })
2505 .ok();
2506 }
2507 });
2508 active_tooltip
2509 .borrow_mut()
2510 .replace(ActiveTooltip::WaitingForShow {
2511 _task: delayed_show_task,
2512 });
2513 }
2514 }
2515}
2516
2517/// Returns a callback which will be called by window prepaint to update tooltip visibility. The
2518/// purpose of doing this logic here instead of the mouse move handler is that the mouse move
2519/// handler won't get called when the element is not painted (e.g. via use of `visible_on_hover`).
2520fn handle_tooltip_check_visible_and_update(
2521 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2522 tooltip_is_hoverable: bool,
2523 check_is_hovered: &Rc<dyn Fn(&Window) -> bool>,
2524 tooltip_bounds: Bounds<Pixels>,
2525 window: &mut Window,
2526 cx: &mut App,
2527) -> bool {
2528 // Separates logic for what mutation should occur from applying it, to avoid overlapping RefCell
2529 // borrows.
2530 enum Action {
2531 None,
2532 Hide,
2533 ScheduleHide(AnyTooltip),
2534 CancelHide(AnyTooltip),
2535 }
2536
2537 let is_hovered = check_is_hovered(window)
2538 || (tooltip_is_hoverable && tooltip_bounds.contains(&window.mouse_position()));
2539 let action = match active_tooltip.borrow().as_ref() {
2540 Some(ActiveTooltip::Visible { tooltip, .. }) => {
2541 if is_hovered {
2542 Action::None
2543 } else {
2544 if tooltip_is_hoverable {
2545 Action::ScheduleHide(tooltip.clone())
2546 } else {
2547 Action::Hide
2548 }
2549 }
2550 }
2551 Some(ActiveTooltip::WaitingForHide { tooltip, .. }) => {
2552 if is_hovered {
2553 Action::CancelHide(tooltip.clone())
2554 } else {
2555 Action::None
2556 }
2557 }
2558 None | Some(ActiveTooltip::WaitingForShow { .. }) => Action::None,
2559 };
2560
2561 match action {
2562 Action::None => {}
2563 Action::Hide => clear_active_tooltip(&active_tooltip, window),
2564 Action::ScheduleHide(tooltip) => {
2565 let delayed_hide_task = window.spawn(cx, {
2566 let active_tooltip = active_tooltip.clone();
2567 move |mut cx| async move {
2568 cx.background_executor()
2569 .timer(HOVERABLE_TOOLTIP_HIDE_DELAY)
2570 .await;
2571 if active_tooltip.borrow_mut().take().is_some() {
2572 cx.update(|window, _cx| window.refresh()).ok();
2573 }
2574 }
2575 });
2576 active_tooltip
2577 .borrow_mut()
2578 .replace(ActiveTooltip::WaitingForHide {
2579 tooltip,
2580 _task: delayed_hide_task,
2581 });
2582 }
2583 Action::CancelHide(tooltip) => {
2584 // Cancel waiting to hide tooltip when it becomes hovered.
2585 active_tooltip.borrow_mut().replace(ActiveTooltip::Visible {
2586 tooltip,
2587 is_hoverable: true,
2588 });
2589 }
2590 }
2591
2592 active_tooltip.borrow().is_some()
2593}
2594
2595#[derive(Default)]
2596pub(crate) struct GroupHitboxes(HashMap<SharedString, SmallVec<[HitboxId; 1]>>);
2597
2598impl Global for GroupHitboxes {}
2599
2600impl GroupHitboxes {
2601 pub fn get(name: &SharedString, cx: &mut App) -> Option<HitboxId> {
2602 cx.default_global::<Self>()
2603 .0
2604 .get(name)
2605 .and_then(|bounds_stack| bounds_stack.last())
2606 .cloned()
2607 }
2608
2609 pub fn push(name: SharedString, hitbox_id: HitboxId, cx: &mut App) {
2610 cx.default_global::<Self>()
2611 .0
2612 .entry(name)
2613 .or_default()
2614 .push(hitbox_id);
2615 }
2616
2617 pub fn pop(name: &SharedString, cx: &mut App) {
2618 cx.default_global::<Self>().0.get_mut(name).unwrap().pop();
2619 }
2620}
2621
2622/// A wrapper around an element that can be focused.
2623pub struct FocusableWrapper<E> {
2624 /// The element that is focusable
2625 pub element: E,
2626}
2627
2628impl<E: InteractiveElement> FocusableElement for FocusableWrapper<E> {}
2629
2630impl<E> InteractiveElement for FocusableWrapper<E>
2631where
2632 E: InteractiveElement,
2633{
2634 fn interactivity(&mut self) -> &mut Interactivity {
2635 self.element.interactivity()
2636 }
2637}
2638
2639impl<E: StatefulInteractiveElement> StatefulInteractiveElement for FocusableWrapper<E> {}
2640
2641impl<E> Styled for FocusableWrapper<E>
2642where
2643 E: Styled,
2644{
2645 fn style(&mut self) -> &mut StyleRefinement {
2646 self.element.style()
2647 }
2648}
2649
2650impl FocusableWrapper<Div> {
2651 /// Add a listener to be called when the children of this `Div` are prepainted.
2652 /// This allows you to store the [`Bounds`] of the children for later use.
2653 pub fn on_children_prepainted(
2654 mut self,
2655 listener: impl Fn(Vec<Bounds<Pixels>>, &mut Window, &mut App) + 'static,
2656 ) -> Self {
2657 self.element = self.element.on_children_prepainted(listener);
2658 self
2659 }
2660}
2661
2662impl<E> Element for FocusableWrapper<E>
2663where
2664 E: Element,
2665{
2666 type RequestLayoutState = E::RequestLayoutState;
2667 type PrepaintState = E::PrepaintState;
2668
2669 fn id(&self) -> Option<ElementId> {
2670 self.element.id()
2671 }
2672
2673 fn request_layout(
2674 &mut self,
2675 id: Option<&GlobalElementId>,
2676 window: &mut Window,
2677 cx: &mut App,
2678 ) -> (LayoutId, Self::RequestLayoutState) {
2679 self.element.request_layout(id, window, cx)
2680 }
2681
2682 fn prepaint(
2683 &mut self,
2684 id: Option<&GlobalElementId>,
2685 bounds: Bounds<Pixels>,
2686 state: &mut Self::RequestLayoutState,
2687 window: &mut Window,
2688 cx: &mut App,
2689 ) -> E::PrepaintState {
2690 self.element.prepaint(id, bounds, state, window, cx)
2691 }
2692
2693 fn paint(
2694 &mut self,
2695 id: Option<&GlobalElementId>,
2696 bounds: Bounds<Pixels>,
2697 request_layout: &mut Self::RequestLayoutState,
2698 prepaint: &mut Self::PrepaintState,
2699 window: &mut Window,
2700 cx: &mut App,
2701 ) {
2702 self.element
2703 .paint(id, bounds, request_layout, prepaint, window, cx)
2704 }
2705}
2706
2707impl<E> IntoElement for FocusableWrapper<E>
2708where
2709 E: IntoElement,
2710{
2711 type Element = E::Element;
2712
2713 fn into_element(self) -> Self::Element {
2714 self.element.into_element()
2715 }
2716}
2717
2718impl<E> ParentElement for FocusableWrapper<E>
2719where
2720 E: ParentElement,
2721{
2722 fn extend(&mut self, elements: impl IntoIterator<Item = AnyElement>) {
2723 self.element.extend(elements)
2724 }
2725}
2726
2727/// A wrapper around an element that can store state, produced after assigning an ElementId.
2728pub struct Stateful<E> {
2729 pub(crate) element: E,
2730}
2731
2732impl<E> Styled for Stateful<E>
2733where
2734 E: Styled,
2735{
2736 fn style(&mut self) -> &mut StyleRefinement {
2737 self.element.style()
2738 }
2739}
2740
2741impl<E> StatefulInteractiveElement for Stateful<E>
2742where
2743 E: Element,
2744 Self: InteractiveElement,
2745{
2746}
2747
2748impl<E> InteractiveElement for Stateful<E>
2749where
2750 E: InteractiveElement,
2751{
2752 fn interactivity(&mut self) -> &mut Interactivity {
2753 self.element.interactivity()
2754 }
2755}
2756
2757impl<E: FocusableElement> FocusableElement for Stateful<E> {}
2758
2759impl<E> Element for Stateful<E>
2760where
2761 E: Element,
2762{
2763 type RequestLayoutState = E::RequestLayoutState;
2764 type PrepaintState = E::PrepaintState;
2765
2766 fn id(&self) -> Option<ElementId> {
2767 self.element.id()
2768 }
2769
2770 fn request_layout(
2771 &mut self,
2772 id: Option<&GlobalElementId>,
2773 window: &mut Window,
2774 cx: &mut App,
2775 ) -> (LayoutId, Self::RequestLayoutState) {
2776 self.element.request_layout(id, window, cx)
2777 }
2778
2779 fn prepaint(
2780 &mut self,
2781 id: Option<&GlobalElementId>,
2782 bounds: Bounds<Pixels>,
2783 state: &mut Self::RequestLayoutState,
2784 window: &mut Window,
2785 cx: &mut App,
2786 ) -> E::PrepaintState {
2787 self.element.prepaint(id, bounds, state, window, cx)
2788 }
2789
2790 fn paint(
2791 &mut self,
2792 id: Option<&GlobalElementId>,
2793 bounds: Bounds<Pixels>,
2794 request_layout: &mut Self::RequestLayoutState,
2795 prepaint: &mut Self::PrepaintState,
2796 window: &mut Window,
2797 cx: &mut App,
2798 ) {
2799 self.element
2800 .paint(id, bounds, request_layout, prepaint, window, cx);
2801 }
2802}
2803
2804impl<E> IntoElement for Stateful<E>
2805where
2806 E: Element,
2807{
2808 type Element = Self;
2809
2810 fn into_element(self) -> Self::Element {
2811 self
2812 }
2813}
2814
2815impl<E> ParentElement for Stateful<E>
2816where
2817 E: ParentElement,
2818{
2819 fn extend(&mut self, elements: impl IntoIterator<Item = AnyElement>) {
2820 self.element.extend(elements)
2821 }
2822}
2823
2824/// Represents an element that can be scrolled *to* in its parent element.
2825///
2826/// Contrary to [ScrollHandle::scroll_to_item], an anchored element does not have to be an immediate child of the parent.
2827#[derive(Clone)]
2828pub struct ScrollAnchor {
2829 handle: ScrollHandle,
2830 last_origin: Rc<RefCell<Point<Pixels>>>,
2831}
2832
2833impl ScrollAnchor {
2834 /// Creates a [ScrollAnchor] associated with a given [ScrollHandle].
2835 pub fn for_handle(handle: ScrollHandle) -> Self {
2836 Self {
2837 handle,
2838 last_origin: Default::default(),
2839 }
2840 }
2841 /// Request scroll to this item on the next frame.
2842 pub fn scroll_to(&self, window: &mut Window, _cx: &mut App) {
2843 let this = self.clone();
2844
2845 window.on_next_frame(move |_, _| {
2846 let viewport_bounds = this.handle.bounds();
2847 let self_bounds = *this.last_origin.borrow();
2848 this.handle.set_offset(viewport_bounds.origin - self_bounds);
2849 });
2850 }
2851}
2852#[derive(Default, Debug)]
2853struct ScrollHandleState {
2854 offset: Rc<RefCell<Point<Pixels>>>,
2855 bounds: Bounds<Pixels>,
2856 child_bounds: Vec<Bounds<Pixels>>,
2857 requested_scroll_top: Option<(usize, Pixels)>,
2858 overflow: Point<Overflow>,
2859}
2860
2861/// A handle to the scrollable aspects of an element.
2862/// Used for accessing scroll state, like the current scroll offset,
2863/// and for mutating the scroll state, like scrolling to a specific child.
2864#[derive(Clone, Debug)]
2865pub struct ScrollHandle(Rc<RefCell<ScrollHandleState>>);
2866
2867impl Default for ScrollHandle {
2868 fn default() -> Self {
2869 Self::new()
2870 }
2871}
2872
2873impl ScrollHandle {
2874 /// Construct a new scroll handle.
2875 pub fn new() -> Self {
2876 Self(Rc::default())
2877 }
2878
2879 /// Get the current scroll offset.
2880 pub fn offset(&self) -> Point<Pixels> {
2881 *self.0.borrow().offset.borrow()
2882 }
2883
2884 /// Get the top child that's scrolled into view.
2885 pub fn top_item(&self) -> usize {
2886 let state = self.0.borrow();
2887 let top = state.bounds.top() - state.offset.borrow().y;
2888
2889 match state.child_bounds.binary_search_by(|bounds| {
2890 if top < bounds.top() {
2891 Ordering::Greater
2892 } else if top > bounds.bottom() {
2893 Ordering::Less
2894 } else {
2895 Ordering::Equal
2896 }
2897 }) {
2898 Ok(ix) => ix,
2899 Err(ix) => ix.min(state.child_bounds.len().saturating_sub(1)),
2900 }
2901 }
2902
2903 /// Return the bounds into which this child is painted
2904 pub fn bounds(&self) -> Bounds<Pixels> {
2905 self.0.borrow().bounds
2906 }
2907
2908 /// Set the bounds into which this child is painted
2909 pub(super) fn set_bounds(&self, bounds: Bounds<Pixels>) {
2910 self.0.borrow_mut().bounds = bounds;
2911 }
2912
2913 /// Get the bounds for a specific child.
2914 pub fn bounds_for_item(&self, ix: usize) -> Option<Bounds<Pixels>> {
2915 self.0.borrow().child_bounds.get(ix).cloned()
2916 }
2917
2918 /// scroll_to_item scrolls the minimal amount to ensure that the child is
2919 /// fully visible
2920 pub fn scroll_to_item(&self, ix: usize) {
2921 let state = self.0.borrow();
2922
2923 let Some(bounds) = state.child_bounds.get(ix) else {
2924 return;
2925 };
2926
2927 let mut scroll_offset = state.offset.borrow_mut();
2928
2929 if state.overflow.y == Overflow::Scroll {
2930 if bounds.top() + scroll_offset.y < state.bounds.top() {
2931 scroll_offset.y = state.bounds.top() - bounds.top();
2932 } else if bounds.bottom() + scroll_offset.y > state.bounds.bottom() {
2933 scroll_offset.y = state.bounds.bottom() - bounds.bottom();
2934 }
2935 }
2936
2937 if state.overflow.x == Overflow::Scroll {
2938 if bounds.left() + scroll_offset.x < state.bounds.left() {
2939 scroll_offset.x = state.bounds.left() - bounds.left();
2940 } else if bounds.right() + scroll_offset.x > state.bounds.right() {
2941 scroll_offset.x = state.bounds.right() - bounds.right();
2942 }
2943 }
2944 }
2945
2946 /// Set the offset explicitly. The offset is the distance from the top left of the
2947 /// parent container to the top left of the first child.
2948 /// As you scroll further down the offset becomes more negative.
2949 pub fn set_offset(&self, mut position: Point<Pixels>) {
2950 let state = self.0.borrow();
2951 *state.offset.borrow_mut() = position;
2952 }
2953
2954 /// Get the logical scroll top, based on a child index and a pixel offset.
2955 pub fn logical_scroll_top(&self) -> (usize, Pixels) {
2956 let ix = self.top_item();
2957 let state = self.0.borrow();
2958
2959 if let Some(child_bounds) = state.child_bounds.get(ix) {
2960 (
2961 ix,
2962 child_bounds.top() + state.offset.borrow().y - state.bounds.top(),
2963 )
2964 } else {
2965 (ix, px(0.))
2966 }
2967 }
2968
2969 /// Set the logical scroll top, based on a child index and a pixel offset.
2970 pub fn set_logical_scroll_top(&self, ix: usize, px: Pixels) {
2971 self.0.borrow_mut().requested_scroll_top = Some((ix, px));
2972 }
2973
2974 /// Get the count of children for scrollable item.
2975 pub fn children_count(&self) -> usize {
2976 self.0.borrow().child_bounds.len()
2977 }
2978}