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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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 [`ViewContext::listener`](crate::ViewContext::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.mouse_up_listeners.is_empty()
1513 || !self.mouse_down_listeners.is_empty()
1514 || !self.mouse_move_listeners.is_empty()
1515 || !self.click_listeners.is_empty()
1516 || !self.scroll_wheel_listeners.is_empty()
1517 || self.drag_listener.is_some()
1518 || !self.drop_listeners.is_empty()
1519 || self.tooltip_builder.is_some()
1520 }
1521
1522 fn clamp_scroll_position(
1523 &self,
1524 bounds: Bounds<Pixels>,
1525 style: &Style,
1526 window: &mut Window,
1527 _cx: &mut App,
1528 ) -> Point<Pixels> {
1529 if let Some(scroll_offset) = self.scroll_offset.as_ref() {
1530 if let Some(scroll_handle) = &self.tracked_scroll_handle {
1531 scroll_handle.0.borrow_mut().overflow = style.overflow;
1532 }
1533
1534 let rem_size = window.rem_size();
1535 let padding_size = size(
1536 style
1537 .padding
1538 .left
1539 .to_pixels(bounds.size.width.into(), rem_size)
1540 + style
1541 .padding
1542 .right
1543 .to_pixels(bounds.size.width.into(), rem_size),
1544 style
1545 .padding
1546 .top
1547 .to_pixels(bounds.size.height.into(), rem_size)
1548 + style
1549 .padding
1550 .bottom
1551 .to_pixels(bounds.size.height.into(), rem_size),
1552 );
1553 let scroll_max = (self.content_size + padding_size - bounds.size).max(&Size::default());
1554 // Clamp scroll offset in case scroll max is smaller now (e.g., if children
1555 // were removed or the bounds became larger).
1556 let mut scroll_offset = scroll_offset.borrow_mut();
1557 scroll_offset.x = scroll_offset.x.clamp(-scroll_max.width, px(0.));
1558 scroll_offset.y = scroll_offset.y.clamp(-scroll_max.height, px(0.));
1559 *scroll_offset
1560 } else {
1561 Point::default()
1562 }
1563 }
1564
1565 /// Paint this element according to this interactivity state's configured styles
1566 /// and bind the element's mouse and keyboard events.
1567 ///
1568 /// content_size is the size of the content of the element, which may be larger than the
1569 /// element's bounds if the element is scrollable.
1570 ///
1571 /// the final computed style will be passed to the provided function, along
1572 /// with the current scroll offset
1573 pub fn paint(
1574 &mut self,
1575 global_id: Option<&GlobalElementId>,
1576 bounds: Bounds<Pixels>,
1577 hitbox: Option<&Hitbox>,
1578 window: &mut Window,
1579 cx: &mut App,
1580 f: impl FnOnce(&Style, &mut Window, &mut App),
1581 ) {
1582 self.hovered = hitbox.map(|hitbox| hitbox.is_hovered(window));
1583 window.with_optional_element_state::<InteractiveElementState, _>(
1584 global_id,
1585 |element_state, window| {
1586 let mut element_state =
1587 element_state.map(|element_state| element_state.unwrap_or_default());
1588
1589 let style = self.compute_style_internal(hitbox, element_state.as_mut(), window, cx);
1590
1591 #[cfg(any(feature = "test-support", test))]
1592 if let Some(debug_selector) = &self.debug_selector {
1593 window
1594 .next_frame
1595 .debug_bounds
1596 .insert(debug_selector.clone(), bounds);
1597 }
1598
1599 self.paint_hover_group_handler(window, cx);
1600
1601 if style.visibility == Visibility::Hidden {
1602 return ((), element_state);
1603 }
1604
1605 window.with_element_opacity(style.opacity, |window| {
1606 style.paint(bounds, window, cx, |window: &mut Window, cx: &mut App| {
1607 window.with_text_style(style.text_style().cloned(), |window| {
1608 window.with_content_mask(
1609 style.overflow_mask(bounds, window.rem_size()),
1610 |window| {
1611 if let Some(hitbox) = hitbox {
1612 #[cfg(debug_assertions)]
1613 self.paint_debug_info(
1614 global_id, hitbox, &style, window, cx,
1615 );
1616
1617 if !cx.has_active_drag() {
1618 if let Some(mouse_cursor) = style.mouse_cursor {
1619 window.set_cursor_style(mouse_cursor, hitbox);
1620 }
1621 }
1622
1623 if let Some(group) = self.group.clone() {
1624 GroupHitboxes::push(group, hitbox.id, cx);
1625 }
1626
1627 self.paint_mouse_listeners(
1628 hitbox,
1629 element_state.as_mut(),
1630 window,
1631 cx,
1632 );
1633 self.paint_scroll_listener(hitbox, &style, window, cx);
1634 }
1635
1636 self.paint_keyboard_listeners(window, cx);
1637 f(&style, window, cx);
1638
1639 if hitbox.is_some() {
1640 if let Some(group) = self.group.as_ref() {
1641 GroupHitboxes::pop(group, cx);
1642 }
1643 }
1644 },
1645 );
1646 });
1647 });
1648 });
1649
1650 ((), element_state)
1651 },
1652 );
1653 }
1654
1655 #[cfg(debug_assertions)]
1656 fn paint_debug_info(
1657 &self,
1658 global_id: Option<&GlobalElementId>,
1659 hitbox: &Hitbox,
1660 style: &Style,
1661 window: &mut Window,
1662 cx: &mut App,
1663 ) {
1664 if global_id.is_some()
1665 && (style.debug || style.debug_below || cx.has_global::<crate::DebugBelow>())
1666 && hitbox.is_hovered(window)
1667 {
1668 const FONT_SIZE: crate::Pixels = crate::Pixels(10.);
1669 let element_id = format!("{:?}", global_id.unwrap());
1670 let str_len = element_id.len();
1671
1672 let render_debug_text = |window: &mut Window| {
1673 if let Some(text) = window
1674 .text_system()
1675 .shape_text(
1676 element_id.into(),
1677 FONT_SIZE,
1678 &[window.text_style().to_run(str_len)],
1679 None,
1680 )
1681 .ok()
1682 .and_then(|mut text| text.pop())
1683 {
1684 text.paint(hitbox.origin, FONT_SIZE, window, cx).ok();
1685
1686 let text_bounds = crate::Bounds {
1687 origin: hitbox.origin,
1688 size: text.size(FONT_SIZE),
1689 };
1690 if self.location.is_some()
1691 && text_bounds.contains(&window.mouse_position())
1692 && window.modifiers().secondary()
1693 {
1694 let secondary_held = window.modifiers().secondary();
1695 window.on_key_event({
1696 move |e: &crate::ModifiersChangedEvent, _phase, window, _cx| {
1697 if e.modifiers.secondary() != secondary_held
1698 && text_bounds.contains(&window.mouse_position())
1699 {
1700 window.refresh();
1701 }
1702 }
1703 });
1704
1705 let was_hovered = hitbox.is_hovered(window);
1706 window.on_mouse_event({
1707 let hitbox = hitbox.clone();
1708 move |_: &MouseMoveEvent, phase, window, _| {
1709 if phase == DispatchPhase::Capture {
1710 let hovered = hitbox.is_hovered(window);
1711 if hovered != was_hovered {
1712 window.refresh();
1713 }
1714 }
1715 }
1716 });
1717
1718 window.on_mouse_event({
1719 let hitbox = hitbox.clone();
1720 let location = self.location.unwrap();
1721 move |e: &crate::MouseDownEvent, phase, window, cx| {
1722 if text_bounds.contains(&e.position)
1723 && phase.capture()
1724 && hitbox.is_hovered(window)
1725 {
1726 cx.stop_propagation();
1727 let Ok(dir) = std::env::current_dir() else {
1728 return;
1729 };
1730
1731 eprintln!(
1732 "This element was created at:\n{}:{}:{}",
1733 dir.join(location.file()).to_string_lossy(),
1734 location.line(),
1735 location.column()
1736 );
1737 }
1738 }
1739 });
1740 window.paint_quad(crate::outline(
1741 crate::Bounds {
1742 origin: hitbox.origin
1743 + crate::point(crate::px(0.), FONT_SIZE - px(2.)),
1744 size: crate::Size {
1745 width: text_bounds.size.width,
1746 height: crate::px(1.),
1747 },
1748 },
1749 crate::red(),
1750 ))
1751 }
1752 }
1753 };
1754
1755 window.with_text_style(
1756 Some(crate::TextStyleRefinement {
1757 color: Some(crate::red()),
1758 line_height: Some(FONT_SIZE.into()),
1759 background_color: Some(crate::white()),
1760 ..Default::default()
1761 }),
1762 render_debug_text,
1763 )
1764 }
1765 }
1766
1767 fn paint_mouse_listeners(
1768 &mut self,
1769 hitbox: &Hitbox,
1770 element_state: Option<&mut InteractiveElementState>,
1771 window: &mut Window,
1772 cx: &mut App,
1773 ) {
1774 // If this element can be focused, register a mouse down listener
1775 // that will automatically transfer focus when hitting the element.
1776 // This behavior can be suppressed by using `cx.prevent_default()`.
1777 if let Some(focus_handle) = self.tracked_focus_handle.clone() {
1778 let hitbox = hitbox.clone();
1779 window.on_mouse_event(move |_: &MouseDownEvent, phase, window, _| {
1780 if phase == DispatchPhase::Bubble
1781 && hitbox.is_hovered(window)
1782 && !window.default_prevented()
1783 {
1784 window.focus(&focus_handle);
1785 // If there is a parent that is also focusable, prevent it
1786 // from transferring focus because we already did so.
1787 window.prevent_default();
1788 }
1789 });
1790 }
1791
1792 for listener in self.mouse_down_listeners.drain(..) {
1793 let hitbox = hitbox.clone();
1794 window.on_mouse_event(move |event: &MouseDownEvent, phase, window, cx| {
1795 listener(event, phase, &hitbox, window, cx);
1796 })
1797 }
1798
1799 for listener in self.mouse_up_listeners.drain(..) {
1800 let hitbox = hitbox.clone();
1801 window.on_mouse_event(move |event: &MouseUpEvent, phase, window, cx| {
1802 listener(event, phase, &hitbox, window, cx);
1803 })
1804 }
1805
1806 for listener in self.mouse_move_listeners.drain(..) {
1807 let hitbox = hitbox.clone();
1808 window.on_mouse_event(move |event: &MouseMoveEvent, phase, window, cx| {
1809 listener(event, phase, &hitbox, window, cx);
1810 })
1811 }
1812
1813 for listener in self.scroll_wheel_listeners.drain(..) {
1814 let hitbox = hitbox.clone();
1815 window.on_mouse_event(move |event: &ScrollWheelEvent, phase, window, cx| {
1816 listener(event, phase, &hitbox, window, cx);
1817 })
1818 }
1819
1820 if self.hover_style.is_some()
1821 || self.base_style.mouse_cursor.is_some()
1822 || cx.active_drag.is_some() && !self.drag_over_styles.is_empty()
1823 {
1824 let hitbox = hitbox.clone();
1825 let was_hovered = hitbox.is_hovered(window);
1826 window.on_mouse_event(move |_: &MouseMoveEvent, phase, window, _cx| {
1827 let hovered = hitbox.is_hovered(window);
1828 if phase == DispatchPhase::Capture && hovered != was_hovered {
1829 window.refresh();
1830 }
1831 });
1832 }
1833
1834 let mut drag_listener = mem::take(&mut self.drag_listener);
1835 let drop_listeners = mem::take(&mut self.drop_listeners);
1836 let click_listeners = mem::take(&mut self.click_listeners);
1837 let can_drop_predicate = mem::take(&mut self.can_drop_predicate);
1838
1839 if !drop_listeners.is_empty() {
1840 let hitbox = hitbox.clone();
1841 window.on_mouse_event({
1842 move |_: &MouseUpEvent, phase, window, cx| {
1843 if let Some(drag) = &cx.active_drag {
1844 if phase == DispatchPhase::Bubble && hitbox.is_hovered(window) {
1845 let drag_state_type = drag.value.as_ref().type_id();
1846 for (drop_state_type, listener) in &drop_listeners {
1847 if *drop_state_type == drag_state_type {
1848 let drag = cx
1849 .active_drag
1850 .take()
1851 .expect("checked for type drag state type above");
1852
1853 let mut can_drop = true;
1854 if let Some(predicate) = &can_drop_predicate {
1855 can_drop = predicate(drag.value.as_ref(), window, cx);
1856 }
1857
1858 if can_drop {
1859 listener(drag.value.as_ref(), window, cx);
1860 window.refresh();
1861 cx.stop_propagation();
1862 }
1863 }
1864 }
1865 }
1866 }
1867 }
1868 });
1869 }
1870
1871 if let Some(element_state) = element_state {
1872 if !click_listeners.is_empty() || drag_listener.is_some() {
1873 let pending_mouse_down = element_state
1874 .pending_mouse_down
1875 .get_or_insert_with(Default::default)
1876 .clone();
1877
1878 let clicked_state = element_state
1879 .clicked_state
1880 .get_or_insert_with(Default::default)
1881 .clone();
1882
1883 window.on_mouse_event({
1884 let pending_mouse_down = pending_mouse_down.clone();
1885 let hitbox = hitbox.clone();
1886 move |event: &MouseDownEvent, phase, window, _cx| {
1887 if phase == DispatchPhase::Bubble
1888 && event.button == MouseButton::Left
1889 && hitbox.is_hovered(window)
1890 {
1891 *pending_mouse_down.borrow_mut() = Some(event.clone());
1892 window.refresh();
1893 }
1894 }
1895 });
1896
1897 window.on_mouse_event({
1898 let pending_mouse_down = pending_mouse_down.clone();
1899 let hitbox = hitbox.clone();
1900 move |event: &MouseMoveEvent, phase, window, cx| {
1901 if phase == DispatchPhase::Capture {
1902 return;
1903 }
1904
1905 let mut pending_mouse_down = pending_mouse_down.borrow_mut();
1906 if let Some(mouse_down) = pending_mouse_down.clone() {
1907 if !cx.has_active_drag()
1908 && (event.position - mouse_down.position).magnitude()
1909 > DRAG_THRESHOLD
1910 {
1911 if let Some((drag_value, drag_listener)) = drag_listener.take() {
1912 *clicked_state.borrow_mut() = ElementClickedState::default();
1913 let cursor_offset = event.position - hitbox.origin;
1914 let drag = (drag_listener)(
1915 drag_value.as_ref(),
1916 cursor_offset,
1917 window,
1918 cx,
1919 );
1920 cx.active_drag = Some(AnyDrag {
1921 view: drag,
1922 value: drag_value,
1923 cursor_offset,
1924 });
1925 pending_mouse_down.take();
1926 window.refresh();
1927 cx.stop_propagation();
1928 }
1929 }
1930 }
1931 }
1932 });
1933
1934 window.on_mouse_event({
1935 let mut captured_mouse_down = None;
1936 let hitbox = hitbox.clone();
1937 move |event: &MouseUpEvent, phase, window, cx| match phase {
1938 // Clear the pending mouse down during the capture phase,
1939 // so that it happens even if another event handler stops
1940 // propagation.
1941 DispatchPhase::Capture => {
1942 let mut pending_mouse_down = pending_mouse_down.borrow_mut();
1943 if pending_mouse_down.is_some() && hitbox.is_hovered(window) {
1944 captured_mouse_down = pending_mouse_down.take();
1945 window.refresh();
1946 }
1947 }
1948 // Fire click handlers during the bubble phase.
1949 DispatchPhase::Bubble => {
1950 if let Some(mouse_down) = captured_mouse_down.take() {
1951 let mouse_click = ClickEvent {
1952 down: mouse_down,
1953 up: event.clone(),
1954 };
1955 for listener in &click_listeners {
1956 listener(&mouse_click, window, cx);
1957 }
1958 }
1959 }
1960 }
1961 });
1962 }
1963
1964 if let Some(hover_listener) = self.hover_listener.take() {
1965 let hitbox = hitbox.clone();
1966 let was_hovered = element_state
1967 .hover_state
1968 .get_or_insert_with(Default::default)
1969 .clone();
1970 let has_mouse_down = element_state
1971 .pending_mouse_down
1972 .get_or_insert_with(Default::default)
1973 .clone();
1974
1975 window.on_mouse_event(move |_: &MouseMoveEvent, phase, window, cx| {
1976 if phase != DispatchPhase::Bubble {
1977 return;
1978 }
1979 let is_hovered = has_mouse_down.borrow().is_none()
1980 && !cx.has_active_drag()
1981 && hitbox.is_hovered(window);
1982 let mut was_hovered = was_hovered.borrow_mut();
1983
1984 if is_hovered != *was_hovered {
1985 *was_hovered = is_hovered;
1986 drop(was_hovered);
1987
1988 hover_listener(&is_hovered, window, cx);
1989 }
1990 });
1991 }
1992
1993 if let Some(tooltip_builder) = self.tooltip_builder.take() {
1994 let active_tooltip = element_state
1995 .active_tooltip
1996 .get_or_insert_with(Default::default)
1997 .clone();
1998 let pending_mouse_down = element_state
1999 .pending_mouse_down
2000 .get_or_insert_with(Default::default)
2001 .clone();
2002
2003 let tooltip_is_hoverable = tooltip_builder.hoverable;
2004 let build_tooltip = Rc::new(move |window: &mut Window, cx: &mut App| {
2005 Some(((tooltip_builder.build)(window, cx), tooltip_is_hoverable))
2006 });
2007 // Use bounds instead of testing hitbox since check_is_hovered is also called
2008 // during prepaint.
2009 let source_bounds = hitbox.bounds;
2010 let check_is_hovered = Rc::new(move |window: &Window| {
2011 pending_mouse_down.borrow().is_none()
2012 && source_bounds.contains(&window.mouse_position())
2013 });
2014 register_tooltip_mouse_handlers(
2015 &active_tooltip,
2016 self.tooltip_id,
2017 build_tooltip,
2018 check_is_hovered,
2019 window,
2020 );
2021 }
2022
2023 let active_state = element_state
2024 .clicked_state
2025 .get_or_insert_with(Default::default)
2026 .clone();
2027 if active_state.borrow().is_clicked() {
2028 window.on_mouse_event(move |_: &MouseUpEvent, phase, window, _cx| {
2029 if phase == DispatchPhase::Capture {
2030 *active_state.borrow_mut() = ElementClickedState::default();
2031 window.refresh();
2032 }
2033 });
2034 } else {
2035 let active_group_hitbox = self
2036 .group_active_style
2037 .as_ref()
2038 .and_then(|group_active| GroupHitboxes::get(&group_active.group, cx));
2039 let hitbox = hitbox.clone();
2040 window.on_mouse_event(move |_: &MouseDownEvent, phase, window, _cx| {
2041 if phase == DispatchPhase::Bubble && !window.default_prevented() {
2042 let group_hovered = active_group_hitbox
2043 .map_or(false, |group_hitbox_id| group_hitbox_id.is_hovered(window));
2044 let element_hovered = hitbox.is_hovered(window);
2045 if group_hovered || element_hovered {
2046 *active_state.borrow_mut() = ElementClickedState {
2047 group: group_hovered,
2048 element: element_hovered,
2049 };
2050 window.refresh();
2051 }
2052 }
2053 });
2054 }
2055 }
2056 }
2057
2058 fn paint_keyboard_listeners(&mut self, window: &mut Window, _cx: &mut App) {
2059 let key_down_listeners = mem::take(&mut self.key_down_listeners);
2060 let key_up_listeners = mem::take(&mut self.key_up_listeners);
2061 let modifiers_changed_listeners = mem::take(&mut self.modifiers_changed_listeners);
2062 let action_listeners = mem::take(&mut self.action_listeners);
2063 if let Some(context) = self.key_context.clone() {
2064 window.set_key_context(context);
2065 }
2066
2067 for listener in key_down_listeners {
2068 window.on_key_event(move |event: &KeyDownEvent, phase, window, cx| {
2069 listener(event, phase, window, cx);
2070 })
2071 }
2072
2073 for listener in key_up_listeners {
2074 window.on_key_event(move |event: &KeyUpEvent, phase, window, cx| {
2075 listener(event, phase, window, cx);
2076 })
2077 }
2078
2079 for listener in modifiers_changed_listeners {
2080 window.on_modifiers_changed(move |event: &ModifiersChangedEvent, window, cx| {
2081 listener(event, window, cx);
2082 })
2083 }
2084
2085 for (action_type, listener) in action_listeners {
2086 window.on_action(action_type, listener)
2087 }
2088 }
2089
2090 fn paint_hover_group_handler(&self, window: &mut Window, cx: &mut App) {
2091 let group_hitbox = self
2092 .group_hover_style
2093 .as_ref()
2094 .and_then(|group_hover| GroupHitboxes::get(&group_hover.group, cx));
2095
2096 if let Some(group_hitbox) = group_hitbox {
2097 let was_hovered = group_hitbox.is_hovered(window);
2098 window.on_mouse_event(move |_: &MouseMoveEvent, phase, window, _cx| {
2099 let hovered = group_hitbox.is_hovered(window);
2100 if phase == DispatchPhase::Capture && hovered != was_hovered {
2101 window.refresh();
2102 }
2103 });
2104 }
2105 }
2106
2107 fn paint_scroll_listener(
2108 &self,
2109 hitbox: &Hitbox,
2110 style: &Style,
2111 window: &mut Window,
2112 _cx: &mut App,
2113 ) {
2114 if let Some(scroll_offset) = self.scroll_offset.clone() {
2115 let overflow = style.overflow;
2116 let allow_concurrent_scroll = style.allow_concurrent_scroll;
2117 let line_height = window.line_height();
2118 let hitbox = hitbox.clone();
2119 window.on_mouse_event(move |event: &ScrollWheelEvent, phase, window, cx| {
2120 if phase == DispatchPhase::Bubble && hitbox.is_hovered(window) {
2121 let mut scroll_offset = scroll_offset.borrow_mut();
2122 let old_scroll_offset = *scroll_offset;
2123 let delta = event.delta.pixel_delta(line_height);
2124
2125 let mut delta_x = Pixels::ZERO;
2126 if overflow.x == Overflow::Scroll {
2127 if !delta.x.is_zero() {
2128 delta_x = delta.x;
2129 } else if overflow.y != Overflow::Scroll {
2130 delta_x = delta.y;
2131 }
2132 }
2133 let mut delta_y = Pixels::ZERO;
2134 if overflow.y == Overflow::Scroll {
2135 if !delta.y.is_zero() {
2136 delta_y = delta.y;
2137 } else if overflow.x != Overflow::Scroll {
2138 delta_y = delta.x;
2139 }
2140 }
2141 if !allow_concurrent_scroll && !delta_x.is_zero() && !delta_y.is_zero() {
2142 if delta_x.abs() > delta_y.abs() {
2143 delta_y = Pixels::ZERO;
2144 } else {
2145 delta_x = Pixels::ZERO;
2146 }
2147 }
2148 scroll_offset.y += delta_y;
2149 scroll_offset.x += delta_x;
2150 cx.stop_propagation();
2151 if *scroll_offset != old_scroll_offset {
2152 window.refresh();
2153 }
2154 }
2155 });
2156 }
2157 }
2158
2159 /// Compute the visual style for this element, based on the current bounds and the element's state.
2160 pub fn compute_style(
2161 &self,
2162 global_id: Option<&GlobalElementId>,
2163 hitbox: Option<&Hitbox>,
2164 window: &mut Window,
2165 cx: &mut App,
2166 ) -> Style {
2167 window.with_optional_element_state(global_id, |element_state, window| {
2168 let mut element_state =
2169 element_state.map(|element_state| element_state.unwrap_or_default());
2170 let style = self.compute_style_internal(hitbox, element_state.as_mut(), window, cx);
2171 (style, element_state)
2172 })
2173 }
2174
2175 /// Called from internal methods that have already called with_element_state.
2176 fn compute_style_internal(
2177 &self,
2178 hitbox: Option<&Hitbox>,
2179 element_state: Option<&mut InteractiveElementState>,
2180 window: &mut Window,
2181 cx: &mut App,
2182 ) -> Style {
2183 let mut style = Style::default();
2184 style.refine(&self.base_style);
2185
2186 if let Some(focus_handle) = self.tracked_focus_handle.as_ref() {
2187 if let Some(in_focus_style) = self.in_focus_style.as_ref() {
2188 if focus_handle.within_focused(window, cx) {
2189 style.refine(in_focus_style);
2190 }
2191 }
2192
2193 if let Some(focus_style) = self.focus_style.as_ref() {
2194 if focus_handle.is_focused(window) {
2195 style.refine(focus_style);
2196 }
2197 }
2198 }
2199
2200 if let Some(hitbox) = hitbox {
2201 if !cx.has_active_drag() {
2202 if let Some(group_hover) = self.group_hover_style.as_ref() {
2203 if let Some(group_hitbox_id) = GroupHitboxes::get(&group_hover.group, cx) {
2204 if group_hitbox_id.is_hovered(window) {
2205 style.refine(&group_hover.style);
2206 }
2207 }
2208 }
2209
2210 if let Some(hover_style) = self.hover_style.as_ref() {
2211 if hitbox.is_hovered(window) {
2212 style.refine(hover_style);
2213 }
2214 }
2215 }
2216
2217 if let Some(drag) = cx.active_drag.take() {
2218 let mut can_drop = true;
2219 if let Some(can_drop_predicate) = &self.can_drop_predicate {
2220 can_drop = can_drop_predicate(drag.value.as_ref(), window, cx);
2221 }
2222
2223 if can_drop {
2224 for (state_type, group_drag_style) in &self.group_drag_over_styles {
2225 if let Some(group_hitbox_id) =
2226 GroupHitboxes::get(&group_drag_style.group, cx)
2227 {
2228 if *state_type == drag.value.as_ref().type_id()
2229 && group_hitbox_id.is_hovered(window)
2230 {
2231 style.refine(&group_drag_style.style);
2232 }
2233 }
2234 }
2235
2236 for (state_type, build_drag_over_style) in &self.drag_over_styles {
2237 if *state_type == drag.value.as_ref().type_id() && hitbox.is_hovered(window)
2238 {
2239 style.refine(&build_drag_over_style(drag.value.as_ref(), window, cx));
2240 }
2241 }
2242 }
2243
2244 cx.active_drag = Some(drag);
2245 }
2246 }
2247
2248 if let Some(element_state) = element_state {
2249 let clicked_state = element_state
2250 .clicked_state
2251 .get_or_insert_with(Default::default)
2252 .borrow();
2253 if clicked_state.group {
2254 if let Some(group) = self.group_active_style.as_ref() {
2255 style.refine(&group.style)
2256 }
2257 }
2258
2259 if let Some(active_style) = self.active_style.as_ref() {
2260 if clicked_state.element {
2261 style.refine(active_style)
2262 }
2263 }
2264 }
2265
2266 style
2267 }
2268}
2269
2270/// The per-frame state of an interactive element. Used for tracking stateful interactions like clicks
2271/// and scroll offsets.
2272#[derive(Default)]
2273pub struct InteractiveElementState {
2274 pub(crate) focus_handle: Option<FocusHandle>,
2275 pub(crate) clicked_state: Option<Rc<RefCell<ElementClickedState>>>,
2276 pub(crate) hover_state: Option<Rc<RefCell<bool>>>,
2277 pub(crate) pending_mouse_down: Option<Rc<RefCell<Option<MouseDownEvent>>>>,
2278 pub(crate) scroll_offset: Option<Rc<RefCell<Point<Pixels>>>>,
2279 pub(crate) active_tooltip: Option<Rc<RefCell<Option<ActiveTooltip>>>>,
2280}
2281
2282/// Whether or not the element or a group that contains it is clicked by the mouse.
2283#[derive(Copy, Clone, Default, Eq, PartialEq)]
2284pub struct ElementClickedState {
2285 /// True if this element's group has been clicked, false otherwise
2286 pub group: bool,
2287
2288 /// True if this element has been clicked, false otherwise
2289 pub element: bool,
2290}
2291
2292impl ElementClickedState {
2293 fn is_clicked(&self) -> bool {
2294 self.group || self.element
2295 }
2296}
2297
2298pub(crate) enum ActiveTooltip {
2299 /// Currently delaying before showing the tooltip.
2300 WaitingForShow { _task: Task<()> },
2301 /// Tooltip is visible, element was hovered or for hoverable tooltips, the tooltip was hovered.
2302 Visible {
2303 tooltip: AnyTooltip,
2304 is_hoverable: bool,
2305 },
2306 /// Tooltip is visible and hoverable, but the mouse is no longer hovering. Currently delaying
2307 /// before hiding it.
2308 WaitingForHide {
2309 tooltip: AnyTooltip,
2310 _task: Task<()>,
2311 },
2312}
2313
2314pub(crate) fn clear_active_tooltip(
2315 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2316 window: &mut Window,
2317) {
2318 match active_tooltip.borrow_mut().take() {
2319 None => {}
2320 Some(ActiveTooltip::WaitingForShow { .. }) => {}
2321 Some(ActiveTooltip::Visible { .. }) => window.refresh(),
2322 Some(ActiveTooltip::WaitingForHide { .. }) => window.refresh(),
2323 }
2324}
2325
2326pub(crate) fn clear_active_tooltip_if_not_hoverable(
2327 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2328 window: &mut Window,
2329) {
2330 let should_clear = match active_tooltip.borrow().as_ref() {
2331 None => false,
2332 Some(ActiveTooltip::WaitingForShow { .. }) => false,
2333 Some(ActiveTooltip::Visible { is_hoverable, .. }) => !is_hoverable,
2334 Some(ActiveTooltip::WaitingForHide { .. }) => false,
2335 };
2336 if should_clear {
2337 active_tooltip.borrow_mut().take();
2338 window.refresh();
2339 }
2340}
2341
2342pub(crate) fn set_tooltip_on_window(
2343 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2344 window: &mut Window,
2345) -> Option<TooltipId> {
2346 let tooltip = match active_tooltip.borrow().as_ref() {
2347 None => return None,
2348 Some(ActiveTooltip::WaitingForShow { .. }) => return None,
2349 Some(ActiveTooltip::Visible { tooltip, .. }) => tooltip.clone(),
2350 Some(ActiveTooltip::WaitingForHide { tooltip, .. }) => tooltip.clone(),
2351 };
2352 Some(window.set_tooltip(tooltip))
2353}
2354
2355pub(crate) fn register_tooltip_mouse_handlers(
2356 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2357 tooltip_id: Option<TooltipId>,
2358 build_tooltip: Rc<dyn Fn(&mut Window, &mut App) -> Option<(AnyView, bool)>>,
2359 check_is_hovered: Rc<dyn Fn(&Window) -> bool>,
2360 window: &mut Window,
2361) {
2362 window.on_mouse_event({
2363 let active_tooltip = active_tooltip.clone();
2364 let build_tooltip = build_tooltip.clone();
2365 let check_is_hovered = check_is_hovered.clone();
2366 move |_: &MouseMoveEvent, phase, window, cx| {
2367 handle_tooltip_mouse_move(
2368 &active_tooltip,
2369 &build_tooltip,
2370 &check_is_hovered,
2371 phase,
2372 window,
2373 cx,
2374 )
2375 }
2376 });
2377
2378 window.on_mouse_event({
2379 let active_tooltip = active_tooltip.clone();
2380 move |_: &MouseDownEvent, _phase, window: &mut Window, _cx| {
2381 if !tooltip_id.map_or(false, |tooltip_id| tooltip_id.is_hovered(window)) {
2382 clear_active_tooltip_if_not_hoverable(&active_tooltip, window);
2383 }
2384 }
2385 });
2386
2387 window.on_mouse_event({
2388 let active_tooltip = active_tooltip.clone();
2389 move |_: &ScrollWheelEvent, _phase, window: &mut Window, _cx| {
2390 if !tooltip_id.map_or(false, |tooltip_id| tooltip_id.is_hovered(window)) {
2391 clear_active_tooltip_if_not_hoverable(&active_tooltip, window);
2392 }
2393 }
2394 });
2395}
2396
2397fn handle_tooltip_mouse_move(
2398 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2399 build_tooltip: &Rc<dyn Fn(&mut Window, &mut App) -> Option<(AnyView, bool)>>,
2400 check_is_hovered: &Rc<dyn Fn(&Window) -> bool>,
2401 phase: DispatchPhase,
2402 window: &mut Window,
2403 cx: &mut App,
2404) {
2405 // Separates logic for what mutation should occur from applying it, to avoid overlapping
2406 // RefCell borrows.
2407 enum Action {
2408 None,
2409 CancelShow,
2410 ScheduleShow,
2411 }
2412
2413 let action = match active_tooltip.borrow().as_ref() {
2414 None => {
2415 let is_hovered = check_is_hovered(window);
2416 if is_hovered && phase.bubble() {
2417 Action::ScheduleShow
2418 } else {
2419 Action::None
2420 }
2421 }
2422 Some(ActiveTooltip::WaitingForShow { .. }) => {
2423 let is_hovered = check_is_hovered(window);
2424 if is_hovered {
2425 Action::None
2426 } else {
2427 Action::CancelShow
2428 }
2429 }
2430 // These are handled in check_visible_and_update.
2431 Some(ActiveTooltip::Visible { .. }) | Some(ActiveTooltip::WaitingForHide { .. }) => {
2432 Action::None
2433 }
2434 };
2435
2436 match action {
2437 Action::None => {}
2438 Action::CancelShow => {
2439 // Cancel waiting to show tooltip when it is no longer hovered.
2440 active_tooltip.borrow_mut().take();
2441 }
2442 Action::ScheduleShow => {
2443 let delayed_show_task = window.spawn(cx, {
2444 let active_tooltip = active_tooltip.clone();
2445 let build_tooltip = build_tooltip.clone();
2446 let check_is_hovered = check_is_hovered.clone();
2447 move |mut cx| async move {
2448 cx.background_executor().timer(TOOLTIP_SHOW_DELAY).await;
2449 cx.update(|window, cx| {
2450 let new_tooltip =
2451 build_tooltip(window, cx).map(|(view, tooltip_is_hoverable)| {
2452 let active_tooltip = active_tooltip.clone();
2453 ActiveTooltip::Visible {
2454 tooltip: AnyTooltip {
2455 view,
2456 mouse_position: window.mouse_position(),
2457 check_visible_and_update: Rc::new(
2458 move |tooltip_bounds, window, cx| {
2459 handle_tooltip_check_visible_and_update(
2460 &active_tooltip,
2461 tooltip_is_hoverable,
2462 &check_is_hovered,
2463 tooltip_bounds,
2464 window,
2465 cx,
2466 )
2467 },
2468 ),
2469 },
2470 is_hoverable: tooltip_is_hoverable,
2471 }
2472 });
2473 *active_tooltip.borrow_mut() = new_tooltip;
2474 window.refresh();
2475 })
2476 .ok();
2477 }
2478 });
2479 active_tooltip
2480 .borrow_mut()
2481 .replace(ActiveTooltip::WaitingForShow {
2482 _task: delayed_show_task,
2483 });
2484 }
2485 }
2486}
2487
2488/// Returns a callback which will be called by window prepaint to update tooltip visibility. The
2489/// purpose of doing this logic here instead of the mouse move handler is that the mouse move
2490/// handler won't get called when the element is not painted (e.g. via use of `visible_on_hover`).
2491fn handle_tooltip_check_visible_and_update(
2492 active_tooltip: &Rc<RefCell<Option<ActiveTooltip>>>,
2493 tooltip_is_hoverable: bool,
2494 check_is_hovered: &Rc<dyn Fn(&Window) -> bool>,
2495 tooltip_bounds: Bounds<Pixels>,
2496 window: &mut Window,
2497 cx: &mut App,
2498) -> bool {
2499 // Separates logic for what mutation should occur from applying it, to avoid overlapping RefCell
2500 // borrows.
2501 enum Action {
2502 None,
2503 Hide,
2504 ScheduleHide(AnyTooltip),
2505 CancelHide(AnyTooltip),
2506 }
2507
2508 let is_hovered = check_is_hovered(window)
2509 || (tooltip_is_hoverable && tooltip_bounds.contains(&window.mouse_position()));
2510 let action = match active_tooltip.borrow().as_ref() {
2511 Some(ActiveTooltip::Visible { tooltip, .. }) => {
2512 if is_hovered {
2513 Action::None
2514 } else {
2515 if tooltip_is_hoverable {
2516 Action::ScheduleHide(tooltip.clone())
2517 } else {
2518 Action::Hide
2519 }
2520 }
2521 }
2522 Some(ActiveTooltip::WaitingForHide { tooltip, .. }) => {
2523 if is_hovered {
2524 Action::CancelHide(tooltip.clone())
2525 } else {
2526 Action::None
2527 }
2528 }
2529 None | Some(ActiveTooltip::WaitingForShow { .. }) => Action::None,
2530 };
2531
2532 match action {
2533 Action::None => {}
2534 Action::Hide => clear_active_tooltip(&active_tooltip, window),
2535 Action::ScheduleHide(tooltip) => {
2536 let delayed_hide_task = window.spawn(cx, {
2537 let active_tooltip = active_tooltip.clone();
2538 move |mut cx| async move {
2539 cx.background_executor()
2540 .timer(HOVERABLE_TOOLTIP_HIDE_DELAY)
2541 .await;
2542 if active_tooltip.borrow_mut().take().is_some() {
2543 cx.update(|window, _cx| window.refresh()).ok();
2544 }
2545 }
2546 });
2547 active_tooltip
2548 .borrow_mut()
2549 .replace(ActiveTooltip::WaitingForHide {
2550 tooltip,
2551 _task: delayed_hide_task,
2552 });
2553 }
2554 Action::CancelHide(tooltip) => {
2555 // Cancel waiting to hide tooltip when it becomes hovered.
2556 active_tooltip.borrow_mut().replace(ActiveTooltip::Visible {
2557 tooltip,
2558 is_hoverable: true,
2559 });
2560 }
2561 }
2562
2563 active_tooltip.borrow().is_some()
2564}
2565
2566#[derive(Default)]
2567pub(crate) struct GroupHitboxes(HashMap<SharedString, SmallVec<[HitboxId; 1]>>);
2568
2569impl Global for GroupHitboxes {}
2570
2571impl GroupHitboxes {
2572 pub fn get(name: &SharedString, cx: &mut App) -> Option<HitboxId> {
2573 cx.default_global::<Self>()
2574 .0
2575 .get(name)
2576 .and_then(|bounds_stack| bounds_stack.last())
2577 .cloned()
2578 }
2579
2580 pub fn push(name: SharedString, hitbox_id: HitboxId, cx: &mut App) {
2581 cx.default_global::<Self>()
2582 .0
2583 .entry(name)
2584 .or_default()
2585 .push(hitbox_id);
2586 }
2587
2588 pub fn pop(name: &SharedString, cx: &mut App) {
2589 cx.default_global::<Self>().0.get_mut(name).unwrap().pop();
2590 }
2591}
2592
2593/// A wrapper around an element that can be focused.
2594pub struct FocusableWrapper<E> {
2595 /// The element that is focusable
2596 pub element: E,
2597}
2598
2599impl<E: InteractiveElement> FocusableElement for FocusableWrapper<E> {}
2600
2601impl<E> InteractiveElement for FocusableWrapper<E>
2602where
2603 E: InteractiveElement,
2604{
2605 fn interactivity(&mut self) -> &mut Interactivity {
2606 self.element.interactivity()
2607 }
2608}
2609
2610impl<E: StatefulInteractiveElement> StatefulInteractiveElement for FocusableWrapper<E> {}
2611
2612impl<E> Styled for FocusableWrapper<E>
2613where
2614 E: Styled,
2615{
2616 fn style(&mut self) -> &mut StyleRefinement {
2617 self.element.style()
2618 }
2619}
2620
2621impl FocusableWrapper<Div> {
2622 /// Add a listener to be called when the children of this `Div` are prepainted.
2623 /// This allows you to store the [`Bounds`] of the children for later use.
2624 pub fn on_children_prepainted(
2625 mut self,
2626 listener: impl Fn(Vec<Bounds<Pixels>>, &mut Window, &mut App) + 'static,
2627 ) -> Self {
2628 self.element = self.element.on_children_prepainted(listener);
2629 self
2630 }
2631}
2632
2633impl<E> Element for FocusableWrapper<E>
2634where
2635 E: Element,
2636{
2637 type RequestLayoutState = E::RequestLayoutState;
2638 type PrepaintState = E::PrepaintState;
2639
2640 fn id(&self) -> Option<ElementId> {
2641 self.element.id()
2642 }
2643
2644 fn request_layout(
2645 &mut self,
2646 id: Option<&GlobalElementId>,
2647 window: &mut Window,
2648 cx: &mut App,
2649 ) -> (LayoutId, Self::RequestLayoutState) {
2650 self.element.request_layout(id, window, cx)
2651 }
2652
2653 fn prepaint(
2654 &mut self,
2655 id: Option<&GlobalElementId>,
2656 bounds: Bounds<Pixels>,
2657 state: &mut Self::RequestLayoutState,
2658 window: &mut Window,
2659 cx: &mut App,
2660 ) -> E::PrepaintState {
2661 self.element.prepaint(id, bounds, state, window, cx)
2662 }
2663
2664 fn paint(
2665 &mut self,
2666 id: Option<&GlobalElementId>,
2667 bounds: Bounds<Pixels>,
2668 request_layout: &mut Self::RequestLayoutState,
2669 prepaint: &mut Self::PrepaintState,
2670 window: &mut Window,
2671 cx: &mut App,
2672 ) {
2673 self.element
2674 .paint(id, bounds, request_layout, prepaint, window, cx)
2675 }
2676}
2677
2678impl<E> IntoElement for FocusableWrapper<E>
2679where
2680 E: IntoElement,
2681{
2682 type Element = E::Element;
2683
2684 fn into_element(self) -> Self::Element {
2685 self.element.into_element()
2686 }
2687}
2688
2689impl<E> ParentElement for FocusableWrapper<E>
2690where
2691 E: ParentElement,
2692{
2693 fn extend(&mut self, elements: impl IntoIterator<Item = AnyElement>) {
2694 self.element.extend(elements)
2695 }
2696}
2697
2698/// A wrapper around an element that can store state, produced after assigning an ElementId.
2699pub struct Stateful<E> {
2700 pub(crate) element: E,
2701}
2702
2703impl<E> Styled for Stateful<E>
2704where
2705 E: Styled,
2706{
2707 fn style(&mut self) -> &mut StyleRefinement {
2708 self.element.style()
2709 }
2710}
2711
2712impl<E> StatefulInteractiveElement for Stateful<E>
2713where
2714 E: Element,
2715 Self: InteractiveElement,
2716{
2717}
2718
2719impl<E> InteractiveElement for Stateful<E>
2720where
2721 E: InteractiveElement,
2722{
2723 fn interactivity(&mut self) -> &mut Interactivity {
2724 self.element.interactivity()
2725 }
2726}
2727
2728impl<E: FocusableElement> FocusableElement for Stateful<E> {}
2729
2730impl<E> Element for Stateful<E>
2731where
2732 E: Element,
2733{
2734 type RequestLayoutState = E::RequestLayoutState;
2735 type PrepaintState = E::PrepaintState;
2736
2737 fn id(&self) -> Option<ElementId> {
2738 self.element.id()
2739 }
2740
2741 fn request_layout(
2742 &mut self,
2743 id: Option<&GlobalElementId>,
2744 window: &mut Window,
2745 cx: &mut App,
2746 ) -> (LayoutId, Self::RequestLayoutState) {
2747 self.element.request_layout(id, window, cx)
2748 }
2749
2750 fn prepaint(
2751 &mut self,
2752 id: Option<&GlobalElementId>,
2753 bounds: Bounds<Pixels>,
2754 state: &mut Self::RequestLayoutState,
2755 window: &mut Window,
2756 cx: &mut App,
2757 ) -> E::PrepaintState {
2758 self.element.prepaint(id, bounds, state, window, cx)
2759 }
2760
2761 fn paint(
2762 &mut self,
2763 id: Option<&GlobalElementId>,
2764 bounds: Bounds<Pixels>,
2765 request_layout: &mut Self::RequestLayoutState,
2766 prepaint: &mut Self::PrepaintState,
2767 window: &mut Window,
2768 cx: &mut App,
2769 ) {
2770 self.element
2771 .paint(id, bounds, request_layout, prepaint, window, cx);
2772 }
2773}
2774
2775impl<E> IntoElement for Stateful<E>
2776where
2777 E: Element,
2778{
2779 type Element = Self;
2780
2781 fn into_element(self) -> Self::Element {
2782 self
2783 }
2784}
2785
2786impl<E> ParentElement for Stateful<E>
2787where
2788 E: ParentElement,
2789{
2790 fn extend(&mut self, elements: impl IntoIterator<Item = AnyElement>) {
2791 self.element.extend(elements)
2792 }
2793}
2794
2795/// Represents an element that can be scrolled *to* in its parent element.
2796///
2797/// Contrary to [ScrollHandle::scroll_to_item], an anchored element does not have to be an immediate child of the parent.
2798#[derive(Clone)]
2799pub struct ScrollAnchor {
2800 handle: ScrollHandle,
2801 last_origin: Rc<RefCell<Point<Pixels>>>,
2802}
2803
2804impl ScrollAnchor {
2805 /// Creates a [ScrollAnchor] associated with a given [ScrollHandle].
2806 pub fn for_handle(handle: ScrollHandle) -> Self {
2807 Self {
2808 handle,
2809 last_origin: Default::default(),
2810 }
2811 }
2812 /// Request scroll to this item on the next frame.
2813 pub fn scroll_to(&self, window: &mut Window, _cx: &mut App) {
2814 let this = self.clone();
2815
2816 window.on_next_frame(move |_, _| {
2817 let viewport_bounds = this.handle.bounds();
2818 let self_bounds = *this.last_origin.borrow();
2819 this.handle.set_offset(viewport_bounds.origin - self_bounds);
2820 });
2821 }
2822}
2823#[derive(Default, Debug)]
2824struct ScrollHandleState {
2825 offset: Rc<RefCell<Point<Pixels>>>,
2826 bounds: Bounds<Pixels>,
2827 child_bounds: Vec<Bounds<Pixels>>,
2828 requested_scroll_top: Option<(usize, Pixels)>,
2829 overflow: Point<Overflow>,
2830}
2831
2832/// A handle to the scrollable aspects of an element.
2833/// Used for accessing scroll state, like the current scroll offset,
2834/// and for mutating the scroll state, like scrolling to a specific child.
2835#[derive(Clone, Debug)]
2836pub struct ScrollHandle(Rc<RefCell<ScrollHandleState>>);
2837
2838impl Default for ScrollHandle {
2839 fn default() -> Self {
2840 Self::new()
2841 }
2842}
2843
2844impl ScrollHandle {
2845 /// Construct a new scroll handle.
2846 pub fn new() -> Self {
2847 Self(Rc::default())
2848 }
2849
2850 /// Get the current scroll offset.
2851 pub fn offset(&self) -> Point<Pixels> {
2852 *self.0.borrow().offset.borrow()
2853 }
2854
2855 /// Get the top child that's scrolled into view.
2856 pub fn top_item(&self) -> usize {
2857 let state = self.0.borrow();
2858 let top = state.bounds.top() - state.offset.borrow().y;
2859
2860 match state.child_bounds.binary_search_by(|bounds| {
2861 if top < bounds.top() {
2862 Ordering::Greater
2863 } else if top > bounds.bottom() {
2864 Ordering::Less
2865 } else {
2866 Ordering::Equal
2867 }
2868 }) {
2869 Ok(ix) => ix,
2870 Err(ix) => ix.min(state.child_bounds.len().saturating_sub(1)),
2871 }
2872 }
2873
2874 /// Return the bounds into which this child is painted
2875 pub fn bounds(&self) -> Bounds<Pixels> {
2876 self.0.borrow().bounds
2877 }
2878
2879 /// Set the bounds into which this child is painted
2880 pub(super) fn set_bounds(&self, bounds: Bounds<Pixels>) {
2881 self.0.borrow_mut().bounds = bounds;
2882 }
2883
2884 /// Get the bounds for a specific child.
2885 pub fn bounds_for_item(&self, ix: usize) -> Option<Bounds<Pixels>> {
2886 self.0.borrow().child_bounds.get(ix).cloned()
2887 }
2888
2889 /// scroll_to_item scrolls the minimal amount to ensure that the child is
2890 /// fully visible
2891 pub fn scroll_to_item(&self, ix: usize) {
2892 let state = self.0.borrow();
2893
2894 let Some(bounds) = state.child_bounds.get(ix) else {
2895 return;
2896 };
2897
2898 let mut scroll_offset = state.offset.borrow_mut();
2899
2900 if state.overflow.y == Overflow::Scroll {
2901 if bounds.top() + scroll_offset.y < state.bounds.top() {
2902 scroll_offset.y = state.bounds.top() - bounds.top();
2903 } else if bounds.bottom() + scroll_offset.y > state.bounds.bottom() {
2904 scroll_offset.y = state.bounds.bottom() - bounds.bottom();
2905 }
2906 }
2907
2908 if state.overflow.x == Overflow::Scroll {
2909 if bounds.left() + scroll_offset.x < state.bounds.left() {
2910 scroll_offset.x = state.bounds.left() - bounds.left();
2911 } else if bounds.right() + scroll_offset.x > state.bounds.right() {
2912 scroll_offset.x = state.bounds.right() - bounds.right();
2913 }
2914 }
2915 }
2916
2917 /// Set the offset explicitly. The offset is the distance from the top left of the
2918 /// parent container to the top left of the first child.
2919 /// As you scroll further down the offset becomes more negative.
2920 pub fn set_offset(&self, mut position: Point<Pixels>) {
2921 let state = self.0.borrow();
2922 *state.offset.borrow_mut() = position;
2923 }
2924
2925 /// Get the logical scroll top, based on a child index and a pixel offset.
2926 pub fn logical_scroll_top(&self) -> (usize, Pixels) {
2927 let ix = self.top_item();
2928 let state = self.0.borrow();
2929
2930 if let Some(child_bounds) = state.child_bounds.get(ix) {
2931 (
2932 ix,
2933 child_bounds.top() + state.offset.borrow().y - state.bounds.top(),
2934 )
2935 } else {
2936 (ix, px(0.))
2937 }
2938 }
2939
2940 /// Set the logical scroll top, based on a child index and a pixel offset.
2941 pub fn set_logical_scroll_top(&self, ix: usize, px: Pixels) {
2942 self.0.borrow_mut().requested_scroll_top = Some((ix, px));
2943 }
2944
2945 /// Get the count of children for scrollable item.
2946 pub fn children_count(&self) -> usize {
2947 self.0.borrow().child_bounds.len()
2948 }
2949}