interactive.rs

  1use crate::{
  2    Bounds, Capslock, Context, Empty, IntoElement, Keystroke, Modifiers, Pixels, Point, Render,
  3    Window, point, seal::Sealed,
  4};
  5use smallvec::SmallVec;
  6use std::{any::Any, fmt::Debug, ops::Deref, path::PathBuf};
  7
  8/// An event from a platform input source.
  9pub trait InputEvent: Sealed + 'static {
 10    /// Convert this event into the platform input enum.
 11    fn to_platform_input(self) -> PlatformInput;
 12}
 13
 14/// A key event from the platform.
 15pub trait KeyEvent: InputEvent {}
 16
 17/// A mouse event from the platform.
 18pub trait MouseEvent: InputEvent {}
 19
 20/// The key down event equivalent for the platform.
 21#[derive(Clone, Debug, Eq, PartialEq)]
 22pub struct KeyDownEvent {
 23    /// The keystroke that was generated.
 24    pub keystroke: Keystroke,
 25
 26    /// Whether the key is currently held down.
 27    pub is_held: bool,
 28
 29    /// Whether to prefer character input over keybindings for this keystroke.
 30    /// In some cases, like AltGr on Windows, modifiers are significant for character input.
 31    pub prefer_character_input: bool,
 32}
 33
 34impl Sealed for KeyDownEvent {}
 35impl InputEvent for KeyDownEvent {
 36    fn to_platform_input(self) -> PlatformInput {
 37        PlatformInput::KeyDown(self)
 38    }
 39}
 40impl KeyEvent for KeyDownEvent {}
 41
 42/// The key up event equivalent for the platform.
 43#[derive(Clone, Debug)]
 44pub struct KeyUpEvent {
 45    /// The keystroke that was released.
 46    pub keystroke: Keystroke,
 47}
 48
 49impl Sealed for KeyUpEvent {}
 50impl InputEvent for KeyUpEvent {
 51    fn to_platform_input(self) -> PlatformInput {
 52        PlatformInput::KeyUp(self)
 53    }
 54}
 55impl KeyEvent for KeyUpEvent {}
 56
 57/// The modifiers changed event equivalent for the platform.
 58#[derive(Clone, Debug, Default)]
 59pub struct ModifiersChangedEvent {
 60    /// The new state of the modifier keys
 61    pub modifiers: Modifiers,
 62    /// The new state of the capslock key
 63    pub capslock: Capslock,
 64}
 65
 66impl Sealed for ModifiersChangedEvent {}
 67impl InputEvent for ModifiersChangedEvent {
 68    fn to_platform_input(self) -> PlatformInput {
 69        PlatformInput::ModifiersChanged(self)
 70    }
 71}
 72impl KeyEvent for ModifiersChangedEvent {}
 73
 74impl Deref for ModifiersChangedEvent {
 75    type Target = Modifiers;
 76
 77    fn deref(&self) -> &Self::Target {
 78        &self.modifiers
 79    }
 80}
 81
 82/// The phase of a touch motion event.
 83/// Based on the winit enum of the same name.
 84#[derive(Clone, Copy, Debug, Default)]
 85pub enum TouchPhase {
 86    /// The touch started.
 87    Started,
 88    /// The touch event is moving.
 89    #[default]
 90    Moved,
 91    /// The touch phase has ended
 92    Ended,
 93}
 94
 95/// A mouse down event from the platform
 96#[derive(Clone, Debug, Default)]
 97pub struct MouseDownEvent {
 98    /// Which mouse button was pressed.
 99    pub button: MouseButton,
100
101    /// The position of the mouse on the window.
102    pub position: Point<Pixels>,
103
104    /// The modifiers that were held down when the mouse was pressed.
105    pub modifiers: Modifiers,
106
107    /// The number of times the button has been clicked.
108    pub click_count: usize,
109
110    /// Whether this is the first, focusing click.
111    pub first_mouse: bool,
112}
113
114impl Sealed for MouseDownEvent {}
115impl InputEvent for MouseDownEvent {
116    fn to_platform_input(self) -> PlatformInput {
117        PlatformInput::MouseDown(self)
118    }
119}
120impl MouseEvent for MouseDownEvent {}
121
122impl MouseDownEvent {
123    /// Returns true if this mouse up event should focus the element.
124    pub fn is_focusing(&self) -> bool {
125        match self.button {
126            MouseButton::Left => true,
127            _ => false,
128        }
129    }
130}
131
132/// A mouse up event from the platform
133#[derive(Clone, Debug, Default)]
134pub struct MouseUpEvent {
135    /// Which mouse button was released.
136    pub button: MouseButton,
137
138    /// The position of the mouse on the window.
139    pub position: Point<Pixels>,
140
141    /// The modifiers that were held down when the mouse was released.
142    pub modifiers: Modifiers,
143
144    /// The number of times the button has been clicked.
145    pub click_count: usize,
146}
147
148impl Sealed for MouseUpEvent {}
149impl InputEvent for MouseUpEvent {
150    fn to_platform_input(self) -> PlatformInput {
151        PlatformInput::MouseUp(self)
152    }
153}
154
155impl MouseEvent for MouseUpEvent {}
156
157impl MouseUpEvent {
158    /// Returns true if this mouse up event should focus the element.
159    pub fn is_focusing(&self) -> bool {
160        match self.button {
161            MouseButton::Left => true,
162            _ => false,
163        }
164    }
165}
166
167/// A click event, generated when a mouse button is pressed and released.
168#[derive(Clone, Debug, Default)]
169pub struct MouseClickEvent {
170    /// The mouse event when the button was pressed.
171    pub down: MouseDownEvent,
172
173    /// The mouse event when the button was released.
174    pub up: MouseUpEvent,
175}
176
177/// The stage of a pressure click event.
178#[derive(Clone, Copy, Debug, Default, PartialEq)]
179pub enum PressureStage {
180    /// No pressure.
181    #[default]
182    Zero,
183    /// Normal click pressure.
184    Normal,
185    /// High pressure, enough to trigger a force click.
186    Force,
187}
188
189/// A mouse pressure event from the platform. Generated when a force-sensitive trackpad is pressed hard.
190/// Currently only implemented for macOS trackpads.
191#[derive(Debug, Clone, Default)]
192pub struct MousePressureEvent {
193    /// Pressure of the current stage as a float between 0 and 1
194    pub pressure: f32,
195    /// The pressure stage of the event.
196    pub stage: PressureStage,
197    /// The position of the mouse on the window.
198    pub position: Point<Pixels>,
199    /// The modifiers that were held down when the mouse pressure changed.
200    pub modifiers: Modifiers,
201}
202
203impl Sealed for MousePressureEvent {}
204impl InputEvent for MousePressureEvent {
205    fn to_platform_input(self) -> PlatformInput {
206        PlatformInput::MousePressure(self)
207    }
208}
209impl MouseEvent for MousePressureEvent {}
210
211/// A click event that was generated by a keyboard button being pressed and released.
212#[derive(Clone, Debug, Default)]
213pub struct KeyboardClickEvent {
214    /// The keyboard button that was pressed to trigger the click.
215    pub button: KeyboardButton,
216
217    /// The bounds of the element that was clicked.
218    pub bounds: Bounds<Pixels>,
219}
220
221/// A click event, generated when a mouse button or keyboard button is pressed and released.
222#[derive(Clone, Debug)]
223pub enum ClickEvent {
224    /// A click event trigger by a mouse button being pressed and released.
225    Mouse(MouseClickEvent),
226    /// A click event trigger by a keyboard button being pressed and released.
227    Keyboard(KeyboardClickEvent),
228}
229
230impl Default for ClickEvent {
231    fn default() -> Self {
232        ClickEvent::Keyboard(KeyboardClickEvent::default())
233    }
234}
235
236impl ClickEvent {
237    /// Returns the modifiers that were held during the click event
238    ///
239    /// `Keyboard`: The keyboard click events never have modifiers.
240    /// `Mouse`: Modifiers that were held during the mouse key up event.
241    pub fn modifiers(&self) -> Modifiers {
242        match self {
243            // Click events are only generated from keyboard events _without any modifiers_, so we know the modifiers are always Default
244            ClickEvent::Keyboard(_) => Modifiers::default(),
245            // Click events on the web only reflect the modifiers for the keyup event,
246            // tested via observing the behavior of the `ClickEvent.shiftKey` field in Chrome 138
247            // under various combinations of modifiers and keyUp / keyDown events.
248            ClickEvent::Mouse(event) => event.up.modifiers,
249        }
250    }
251
252    /// Returns the position of the click event
253    ///
254    /// `Keyboard`: The bottom left corner of the clicked hitbox
255    /// `Mouse`: The position of the mouse when the button was released.
256    pub fn position(&self) -> Point<Pixels> {
257        match self {
258            ClickEvent::Keyboard(event) => event.bounds.bottom_left(),
259            ClickEvent::Mouse(event) => event.up.position,
260        }
261    }
262
263    /// Returns the mouse position of the click event
264    ///
265    /// `Keyboard`: None
266    /// `Mouse`: The position of the mouse when the button was released.
267    pub fn mouse_position(&self) -> Option<Point<Pixels>> {
268        match self {
269            ClickEvent::Keyboard(_) => None,
270            ClickEvent::Mouse(event) => Some(event.up.position),
271        }
272    }
273
274    /// Returns if this was a right click
275    ///
276    /// `Keyboard`: false
277    /// `Mouse`: Whether the right button was pressed and released
278    pub fn is_right_click(&self) -> bool {
279        match self {
280            ClickEvent::Keyboard(_) => false,
281            ClickEvent::Mouse(event) => {
282                event.down.button == MouseButton::Right && event.up.button == MouseButton::Right
283            }
284        }
285    }
286
287    /// Returns whether the click was a standard click
288    ///
289    /// `Keyboard`: Always true
290    /// `Mouse`: Left button pressed and released
291    pub fn standard_click(&self) -> bool {
292        match self {
293            ClickEvent::Keyboard(_) => true,
294            ClickEvent::Mouse(event) => {
295                event.down.button == MouseButton::Left && event.up.button == MouseButton::Left
296            }
297        }
298    }
299
300    /// Returns whether the click focused the element
301    ///
302    /// `Keyboard`: false, keyboard clicks only work if an element is already focused
303    /// `Mouse`: Whether this was the first focusing click
304    pub fn first_focus(&self) -> bool {
305        match self {
306            ClickEvent::Keyboard(_) => false,
307            ClickEvent::Mouse(event) => event.down.first_mouse,
308        }
309    }
310
311    /// Returns the click count of the click event
312    ///
313    /// `Keyboard`: Always 1
314    /// `Mouse`: Count of clicks from MouseUpEvent
315    pub fn click_count(&self) -> usize {
316        match self {
317            ClickEvent::Keyboard(_) => 1,
318            ClickEvent::Mouse(event) => event.up.click_count,
319        }
320    }
321
322    /// Returns whether the click event is generated by a keyboard event
323    pub fn is_keyboard(&self) -> bool {
324        match self {
325            ClickEvent::Mouse(_) => false,
326            ClickEvent::Keyboard(_) => true,
327        }
328    }
329}
330
331/// An enum representing the keyboard button that was pressed for a click event.
332#[derive(Hash, PartialEq, Eq, Copy, Clone, Debug, Default)]
333pub enum KeyboardButton {
334    /// Enter key was clicked
335    #[default]
336    Enter,
337    /// Space key was clicked
338    Space,
339}
340
341/// An enum representing the mouse button that was pressed.
342#[derive(Hash, Default, PartialEq, Eq, Copy, Clone, Debug)]
343pub enum MouseButton {
344    /// The left mouse button.
345    #[default]
346    Left,
347
348    /// The right mouse button.
349    Right,
350
351    /// The middle mouse button.
352    Middle,
353
354    /// A navigation button, such as back or forward.
355    Navigate(NavigationDirection),
356}
357
358impl MouseButton {
359    /// Get all the mouse buttons in a list.
360    pub fn all() -> Vec<Self> {
361        vec![
362            MouseButton::Left,
363            MouseButton::Right,
364            MouseButton::Middle,
365            MouseButton::Navigate(NavigationDirection::Back),
366            MouseButton::Navigate(NavigationDirection::Forward),
367        ]
368    }
369}
370
371/// A navigation direction, such as back or forward.
372#[derive(Hash, Default, PartialEq, Eq, Copy, Clone, Debug)]
373pub enum NavigationDirection {
374    /// The back button.
375    #[default]
376    Back,
377
378    /// The forward button.
379    Forward,
380}
381
382/// A mouse move event from the platform.
383#[derive(Clone, Debug, Default)]
384pub struct MouseMoveEvent {
385    /// The position of the mouse on the window.
386    pub position: Point<Pixels>,
387
388    /// The mouse button that was pressed, if any.
389    pub pressed_button: Option<MouseButton>,
390
391    /// The modifiers that were held down when the mouse was moved.
392    pub modifiers: Modifiers,
393}
394
395impl Sealed for MouseMoveEvent {}
396impl InputEvent for MouseMoveEvent {
397    fn to_platform_input(self) -> PlatformInput {
398        PlatformInput::MouseMove(self)
399    }
400}
401impl MouseEvent for MouseMoveEvent {}
402
403impl MouseMoveEvent {
404    /// Returns true if the left mouse button is currently held down.
405    pub fn dragging(&self) -> bool {
406        self.pressed_button == Some(MouseButton::Left)
407    }
408}
409
410/// A mouse wheel event from the platform.
411#[derive(Clone, Debug, Default)]
412pub struct ScrollWheelEvent {
413    /// The position of the mouse on the window.
414    pub position: Point<Pixels>,
415
416    /// The change in scroll wheel position for this event.
417    pub delta: ScrollDelta,
418
419    /// The modifiers that were held down when the mouse was moved.
420    pub modifiers: Modifiers,
421
422    /// The phase of the touch event.
423    pub touch_phase: TouchPhase,
424}
425
426impl Sealed for ScrollWheelEvent {}
427impl InputEvent for ScrollWheelEvent {
428    fn to_platform_input(self) -> PlatformInput {
429        PlatformInput::ScrollWheel(self)
430    }
431}
432impl MouseEvent for ScrollWheelEvent {}
433
434impl Deref for ScrollWheelEvent {
435    type Target = Modifiers;
436
437    fn deref(&self) -> &Self::Target {
438        &self.modifiers
439    }
440}
441
442/// The scroll delta for a scroll wheel event.
443#[derive(Clone, Copy, Debug)]
444pub enum ScrollDelta {
445    /// An exact scroll delta in pixels.
446    Pixels(Point<Pixels>),
447    /// An inexact scroll delta in lines.
448    Lines(Point<f32>),
449}
450
451impl Default for ScrollDelta {
452    fn default() -> Self {
453        Self::Lines(Default::default())
454    }
455}
456
457impl ScrollDelta {
458    /// Returns true if this is a precise scroll delta in pixels.
459    pub fn precise(&self) -> bool {
460        match self {
461            ScrollDelta::Pixels(_) => true,
462            ScrollDelta::Lines(_) => false,
463        }
464    }
465
466    /// Converts this scroll event into exact pixels.
467    pub fn pixel_delta(&self, line_height: Pixels) -> Point<Pixels> {
468        match self {
469            ScrollDelta::Pixels(delta) => *delta,
470            ScrollDelta::Lines(delta) => point(line_height * delta.x, line_height * delta.y),
471        }
472    }
473
474    /// Combines two scroll deltas into one.
475    /// If the signs of the deltas are the same (both positive or both negative),
476    /// the deltas are added together. If the signs are opposite, the second delta
477    /// (other) is used, effectively overriding the first delta.
478    pub fn coalesce(self, other: ScrollDelta) -> ScrollDelta {
479        match (self, other) {
480            (ScrollDelta::Pixels(a), ScrollDelta::Pixels(b)) => {
481                let x = if a.x.signum() == b.x.signum() {
482                    a.x + b.x
483                } else {
484                    b.x
485                };
486
487                let y = if a.y.signum() == b.y.signum() {
488                    a.y + b.y
489                } else {
490                    b.y
491                };
492
493                ScrollDelta::Pixels(point(x, y))
494            }
495
496            (ScrollDelta::Lines(a), ScrollDelta::Lines(b)) => {
497                let x = if a.x.signum() == b.x.signum() {
498                    a.x + b.x
499                } else {
500                    b.x
501                };
502
503                let y = if a.y.signum() == b.y.signum() {
504                    a.y + b.y
505                } else {
506                    b.y
507                };
508
509                ScrollDelta::Lines(point(x, y))
510            }
511
512            _ => other,
513        }
514    }
515}
516
517/// A mouse exit event from the platform, generated when the mouse leaves the window.
518#[derive(Clone, Debug, Default)]
519pub struct MouseExitEvent {
520    /// The position of the mouse relative to the window.
521    pub position: Point<Pixels>,
522    /// The mouse button that was pressed, if any.
523    pub pressed_button: Option<MouseButton>,
524    /// The modifiers that were held down when the mouse was moved.
525    pub modifiers: Modifiers,
526}
527
528impl Sealed for MouseExitEvent {}
529impl InputEvent for MouseExitEvent {
530    fn to_platform_input(self) -> PlatformInput {
531        PlatformInput::MouseExited(self)
532    }
533}
534
535impl MouseEvent for MouseExitEvent {}
536
537impl Deref for MouseExitEvent {
538    type Target = Modifiers;
539
540    fn deref(&self) -> &Self::Target {
541        &self.modifiers
542    }
543}
544
545/// A collection of paths from the platform, such as from a file drop.
546#[derive(Debug, Clone, Default, Eq, PartialEq)]
547pub struct ExternalPaths(pub(crate) SmallVec<[PathBuf; 2]>);
548
549impl ExternalPaths {
550    /// Convert this collection of paths into a slice.
551    pub fn paths(&self) -> &[PathBuf] {
552        &self.0
553    }
554}
555
556impl Render for ExternalPaths {
557    fn render(&mut self, _: &mut Window, _: &mut Context<Self>) -> impl IntoElement {
558        // the platform will render icons for the dragged files
559        Empty
560    }
561}
562
563/// A file drop event from the platform, generated when files are dragged and dropped onto the window.
564#[derive(Debug, Clone)]
565pub enum FileDropEvent {
566    /// The files have entered the window.
567    Entered {
568        /// The position of the mouse relative to the window.
569        position: Point<Pixels>,
570        /// The paths of the files that are being dragged.
571        paths: ExternalPaths,
572    },
573    /// The files are being dragged over the window
574    Pending {
575        /// The position of the mouse relative to the window.
576        position: Point<Pixels>,
577    },
578    /// The files have been dropped onto the window.
579    Submit {
580        /// The position of the mouse relative to the window.
581        position: Point<Pixels>,
582    },
583    /// The user has stopped dragging the files over the window.
584    Exited,
585}
586
587impl Sealed for FileDropEvent {}
588impl InputEvent for FileDropEvent {
589    fn to_platform_input(self) -> PlatformInput {
590        PlatformInput::FileDrop(self)
591    }
592}
593impl MouseEvent for FileDropEvent {}
594
595/// An enum corresponding to all kinds of platform input events.
596#[derive(Clone, Debug)]
597pub enum PlatformInput {
598    /// A key was pressed.
599    KeyDown(KeyDownEvent),
600    /// A key was released.
601    KeyUp(KeyUpEvent),
602    /// The keyboard modifiers were changed.
603    ModifiersChanged(ModifiersChangedEvent),
604    /// The mouse was pressed.
605    MouseDown(MouseDownEvent),
606    /// The mouse was released.
607    MouseUp(MouseUpEvent),
608    /// Mouse pressure.
609    MousePressure(MousePressureEvent),
610    /// The mouse was moved.
611    MouseMove(MouseMoveEvent),
612    /// The mouse exited the window.
613    MouseExited(MouseExitEvent),
614    /// The scroll wheel was used.
615    ScrollWheel(ScrollWheelEvent),
616    /// Files were dragged and dropped onto the window.
617    FileDrop(FileDropEvent),
618}
619
620impl PlatformInput {
621    pub(crate) fn mouse_event(&self) -> Option<&dyn Any> {
622        match self {
623            PlatformInput::KeyDown { .. } => None,
624            PlatformInput::KeyUp { .. } => None,
625            PlatformInput::ModifiersChanged { .. } => None,
626            PlatformInput::MouseDown(event) => Some(event),
627            PlatformInput::MouseUp(event) => Some(event),
628            PlatformInput::MouseMove(event) => Some(event),
629            PlatformInput::MousePressure(event) => Some(event),
630            PlatformInput::MouseExited(event) => Some(event),
631            PlatformInput::ScrollWheel(event) => Some(event),
632            PlatformInput::FileDrop(event) => Some(event),
633        }
634    }
635
636    pub(crate) fn keyboard_event(&self) -> Option<&dyn Any> {
637        match self {
638            PlatformInput::KeyDown(event) => Some(event),
639            PlatformInput::KeyUp(event) => Some(event),
640            PlatformInput::ModifiersChanged(event) => Some(event),
641            PlatformInput::MouseDown(_) => None,
642            PlatformInput::MouseUp(_) => None,
643            PlatformInput::MouseMove(_) => None,
644            PlatformInput::MousePressure(_) => None,
645            PlatformInput::MouseExited(_) => None,
646            PlatformInput::ScrollWheel(_) => None,
647            PlatformInput::FileDrop(_) => None,
648        }
649    }
650}
651
652#[cfg(test)]
653mod test {
654
655    use crate::{
656        self as gpui, AppContext as _, Context, FocusHandle, InteractiveElement, IntoElement,
657        KeyBinding, Keystroke, ParentElement, Render, TestAppContext, Window, div,
658    };
659
660    struct TestView {
661        saw_key_down: bool,
662        saw_action: bool,
663        focus_handle: FocusHandle,
664    }
665
666    actions!(test_only, [TestAction]);
667
668    impl Render for TestView {
669        fn render(&mut self, _: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
670            div().id("testview").child(
671                div()
672                    .key_context("parent")
673                    .on_key_down(cx.listener(|this, _, _, cx| {
674                        cx.stop_propagation();
675                        this.saw_key_down = true
676                    }))
677                    .on_action(cx.listener(|this: &mut TestView, _: &TestAction, _, _| {
678                        this.saw_action = true
679                    }))
680                    .child(
681                        div()
682                            .key_context("nested")
683                            .track_focus(&self.focus_handle)
684                            .into_element(),
685                    ),
686            )
687        }
688    }
689
690    #[gpui::test]
691    fn test_on_events(cx: &mut TestAppContext) {
692        let window = cx.update(|cx| {
693            cx.open_window(Default::default(), |_, cx| {
694                cx.new(|cx| TestView {
695                    saw_key_down: false,
696                    saw_action: false,
697                    focus_handle: cx.focus_handle(),
698                })
699            })
700            .unwrap()
701        });
702
703        cx.update(|cx| {
704            cx.bind_keys(vec![KeyBinding::new("ctrl-g", TestAction, Some("parent"))]);
705        });
706
707        window
708            .update(cx, |test_view, window, _cx| {
709                window.focus(&test_view.focus_handle)
710            })
711            .unwrap();
712
713        cx.dispatch_keystroke(*window, Keystroke::parse("a").unwrap());
714        cx.dispatch_keystroke(*window, Keystroke::parse("ctrl-g").unwrap());
715
716        window
717            .update(cx, |test_view, _, _| {
718                assert!(test_view.saw_key_down || test_view.saw_action);
719                assert!(test_view.saw_key_down);
720                assert!(test_view.saw_action);
721            })
722            .unwrap();
723    }
724}