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/// A click event that was generated by a keyboard button being pressed and released.
178#[derive(Clone, Debug, Default)]
179pub struct KeyboardClickEvent {
180    /// The keyboard button that was pressed to trigger the click.
181    pub button: KeyboardButton,
182
183    /// The bounds of the element that was clicked.
184    pub bounds: Bounds<Pixels>,
185}
186
187/// A click event, generated when a mouse button or keyboard button is pressed and released.
188#[derive(Clone, Debug)]
189pub enum ClickEvent {
190    /// A click event trigger by a mouse button being pressed and released.
191    Mouse(MouseClickEvent),
192    /// A click event trigger by a keyboard button being pressed and released.
193    Keyboard(KeyboardClickEvent),
194}
195
196impl Default for ClickEvent {
197    fn default() -> Self {
198        ClickEvent::Keyboard(KeyboardClickEvent::default())
199    }
200}
201
202impl ClickEvent {
203    /// Returns the modifiers that were held during the click event
204    ///
205    /// `Keyboard`: The keyboard click events never have modifiers.
206    /// `Mouse`: Modifiers that were held during the mouse key up event.
207    pub fn modifiers(&self) -> Modifiers {
208        match self {
209            // Click events are only generated from keyboard events _without any modifiers_, so we know the modifiers are always Default
210            ClickEvent::Keyboard(_) => Modifiers::default(),
211            // Click events on the web only reflect the modifiers for the keyup event,
212            // tested via observing the behavior of the `ClickEvent.shiftKey` field in Chrome 138
213            // under various combinations of modifiers and keyUp / keyDown events.
214            ClickEvent::Mouse(event) => event.up.modifiers,
215        }
216    }
217
218    /// Returns the position of the click event
219    ///
220    /// `Keyboard`: The bottom left corner of the clicked hitbox
221    /// `Mouse`: The position of the mouse when the button was released.
222    pub fn position(&self) -> Point<Pixels> {
223        match self {
224            ClickEvent::Keyboard(event) => event.bounds.bottom_left(),
225            ClickEvent::Mouse(event) => event.up.position,
226        }
227    }
228
229    /// Returns the mouse position of the click event
230    ///
231    /// `Keyboard`: None
232    /// `Mouse`: The position of the mouse when the button was released.
233    pub fn mouse_position(&self) -> Option<Point<Pixels>> {
234        match self {
235            ClickEvent::Keyboard(_) => None,
236            ClickEvent::Mouse(event) => Some(event.up.position),
237        }
238    }
239
240    /// Returns if this was a right click
241    ///
242    /// `Keyboard`: false
243    /// `Mouse`: Whether the right button was pressed and released
244    pub fn is_right_click(&self) -> bool {
245        match self {
246            ClickEvent::Keyboard(_) => false,
247            ClickEvent::Mouse(event) => {
248                event.down.button == MouseButton::Right && event.up.button == MouseButton::Right
249            }
250        }
251    }
252
253    /// Returns whether the click was a standard click
254    ///
255    /// `Keyboard`: Always true
256    /// `Mouse`: Left button pressed and released
257    pub fn standard_click(&self) -> bool {
258        match self {
259            ClickEvent::Keyboard(_) => true,
260            ClickEvent::Mouse(event) => {
261                event.down.button == MouseButton::Left && event.up.button == MouseButton::Left
262            }
263        }
264    }
265
266    /// Returns whether the click focused the element
267    ///
268    /// `Keyboard`: false, keyboard clicks only work if an element is already focused
269    /// `Mouse`: Whether this was the first focusing click
270    pub fn first_focus(&self) -> bool {
271        match self {
272            ClickEvent::Keyboard(_) => false,
273            ClickEvent::Mouse(event) => event.down.first_mouse,
274        }
275    }
276
277    /// Returns the click count of the click event
278    ///
279    /// `Keyboard`: Always 1
280    /// `Mouse`: Count of clicks from MouseUpEvent
281    pub fn click_count(&self) -> usize {
282        match self {
283            ClickEvent::Keyboard(_) => 1,
284            ClickEvent::Mouse(event) => event.up.click_count,
285        }
286    }
287
288    /// Returns whether the click event is generated by a keyboard event
289    pub fn is_keyboard(&self) -> bool {
290        match self {
291            ClickEvent::Mouse(_) => false,
292            ClickEvent::Keyboard(_) => true,
293        }
294    }
295}
296
297/// An enum representing the keyboard button that was pressed for a click event.
298#[derive(Hash, PartialEq, Eq, Copy, Clone, Debug, Default)]
299pub enum KeyboardButton {
300    /// Enter key was clicked
301    #[default]
302    Enter,
303    /// Space key was clicked
304    Space,
305}
306
307/// An enum representing the mouse button that was pressed.
308#[derive(Hash, Default, PartialEq, Eq, Copy, Clone, Debug)]
309pub enum MouseButton {
310    /// The left mouse button.
311    #[default]
312    Left,
313
314    /// The right mouse button.
315    Right,
316
317    /// The middle mouse button.
318    Middle,
319
320    /// A navigation button, such as back or forward.
321    Navigate(NavigationDirection),
322}
323
324impl MouseButton {
325    /// Get all the mouse buttons in a list.
326    pub fn all() -> Vec<Self> {
327        vec![
328            MouseButton::Left,
329            MouseButton::Right,
330            MouseButton::Middle,
331            MouseButton::Navigate(NavigationDirection::Back),
332            MouseButton::Navigate(NavigationDirection::Forward),
333        ]
334    }
335}
336
337/// A navigation direction, such as back or forward.
338#[derive(Hash, Default, PartialEq, Eq, Copy, Clone, Debug)]
339pub enum NavigationDirection {
340    /// The back button.
341    #[default]
342    Back,
343
344    /// The forward button.
345    Forward,
346}
347
348/// A mouse move event from the platform.
349#[derive(Clone, Debug, Default)]
350pub struct MouseMoveEvent {
351    /// The position of the mouse on the window.
352    pub position: Point<Pixels>,
353
354    /// The mouse button that was pressed, if any.
355    pub pressed_button: Option<MouseButton>,
356
357    /// The modifiers that were held down when the mouse was moved.
358    pub modifiers: Modifiers,
359}
360
361impl Sealed for MouseMoveEvent {}
362impl InputEvent for MouseMoveEvent {
363    fn to_platform_input(self) -> PlatformInput {
364        PlatformInput::MouseMove(self)
365    }
366}
367impl MouseEvent for MouseMoveEvent {}
368
369impl MouseMoveEvent {
370    /// Returns true if the left mouse button is currently held down.
371    pub fn dragging(&self) -> bool {
372        self.pressed_button == Some(MouseButton::Left)
373    }
374}
375
376/// A mouse wheel event from the platform.
377#[derive(Clone, Debug, Default)]
378pub struct ScrollWheelEvent {
379    /// The position of the mouse on the window.
380    pub position: Point<Pixels>,
381
382    /// The change in scroll wheel position for this event.
383    pub delta: ScrollDelta,
384
385    /// The modifiers that were held down when the mouse was moved.
386    pub modifiers: Modifiers,
387
388    /// The phase of the touch event.
389    pub touch_phase: TouchPhase,
390}
391
392impl Sealed for ScrollWheelEvent {}
393impl InputEvent for ScrollWheelEvent {
394    fn to_platform_input(self) -> PlatformInput {
395        PlatformInput::ScrollWheel(self)
396    }
397}
398impl MouseEvent for ScrollWheelEvent {}
399
400impl Deref for ScrollWheelEvent {
401    type Target = Modifiers;
402
403    fn deref(&self) -> &Self::Target {
404        &self.modifiers
405    }
406}
407
408/// The scroll delta for a scroll wheel event.
409#[derive(Clone, Copy, Debug)]
410pub enum ScrollDelta {
411    /// An exact scroll delta in pixels.
412    Pixels(Point<Pixels>),
413    /// An inexact scroll delta in lines.
414    Lines(Point<f32>),
415}
416
417impl Default for ScrollDelta {
418    fn default() -> Self {
419        Self::Lines(Default::default())
420    }
421}
422
423impl ScrollDelta {
424    /// Returns true if this is a precise scroll delta in pixels.
425    pub fn precise(&self) -> bool {
426        match self {
427            ScrollDelta::Pixels(_) => true,
428            ScrollDelta::Lines(_) => false,
429        }
430    }
431
432    /// Converts this scroll event into exact pixels.
433    pub fn pixel_delta(&self, line_height: Pixels) -> Point<Pixels> {
434        match self {
435            ScrollDelta::Pixels(delta) => *delta,
436            ScrollDelta::Lines(delta) => point(line_height * delta.x, line_height * delta.y),
437        }
438    }
439
440    /// Combines two scroll deltas into one.
441    /// If the signs of the deltas are the same (both positive or both negative),
442    /// the deltas are added together. If the signs are opposite, the second delta
443    /// (other) is used, effectively overriding the first delta.
444    pub fn coalesce(self, other: ScrollDelta) -> ScrollDelta {
445        match (self, other) {
446            (ScrollDelta::Pixels(a), ScrollDelta::Pixels(b)) => {
447                let x = if a.x.signum() == b.x.signum() {
448                    a.x + b.x
449                } else {
450                    b.x
451                };
452
453                let y = if a.y.signum() == b.y.signum() {
454                    a.y + b.y
455                } else {
456                    b.y
457                };
458
459                ScrollDelta::Pixels(point(x, y))
460            }
461
462            (ScrollDelta::Lines(a), ScrollDelta::Lines(b)) => {
463                let x = if a.x.signum() == b.x.signum() {
464                    a.x + b.x
465                } else {
466                    b.x
467                };
468
469                let y = if a.y.signum() == b.y.signum() {
470                    a.y + b.y
471                } else {
472                    b.y
473                };
474
475                ScrollDelta::Lines(point(x, y))
476            }
477
478            _ => other,
479        }
480    }
481}
482
483/// A mouse exit event from the platform, generated when the mouse leaves the window.
484#[derive(Clone, Debug, Default)]
485pub struct MouseExitEvent {
486    /// The position of the mouse relative to the window.
487    pub position: Point<Pixels>,
488    /// The mouse button that was pressed, if any.
489    pub pressed_button: Option<MouseButton>,
490    /// The modifiers that were held down when the mouse was moved.
491    pub modifiers: Modifiers,
492}
493
494impl Sealed for MouseExitEvent {}
495impl InputEvent for MouseExitEvent {
496    fn to_platform_input(self) -> PlatformInput {
497        PlatformInput::MouseExited(self)
498    }
499}
500
501impl MouseEvent for MouseExitEvent {}
502
503impl Deref for MouseExitEvent {
504    type Target = Modifiers;
505
506    fn deref(&self) -> &Self::Target {
507        &self.modifiers
508    }
509}
510
511/// A collection of paths from the platform, such as from a file drop.
512#[derive(Debug, Clone, Default)]
513pub struct ExternalPaths(pub(crate) SmallVec<[PathBuf; 2]>);
514
515impl ExternalPaths {
516    /// Convert this collection of paths into a slice.
517    pub fn paths(&self) -> &[PathBuf] {
518        &self.0
519    }
520}
521
522impl Render for ExternalPaths {
523    fn render(&mut self, _: &mut Window, _: &mut Context<Self>) -> impl IntoElement {
524        // the platform will render icons for the dragged files
525        Empty
526    }
527}
528
529/// A file drop event from the platform, generated when files are dragged and dropped onto the window.
530#[derive(Debug, Clone)]
531pub enum FileDropEvent {
532    /// The files have entered the window.
533    Entered {
534        /// The position of the mouse relative to the window.
535        position: Point<Pixels>,
536        /// The paths of the files that are being dragged.
537        paths: ExternalPaths,
538    },
539    /// The files are being dragged over the window
540    Pending {
541        /// The position of the mouse relative to the window.
542        position: Point<Pixels>,
543    },
544    /// The files have been dropped onto the window.
545    Submit {
546        /// The position of the mouse relative to the window.
547        position: Point<Pixels>,
548    },
549    /// The user has stopped dragging the files over the window.
550    Exited,
551}
552
553impl Sealed for FileDropEvent {}
554impl InputEvent for FileDropEvent {
555    fn to_platform_input(self) -> PlatformInput {
556        PlatformInput::FileDrop(self)
557    }
558}
559impl MouseEvent for FileDropEvent {}
560
561/// An enum corresponding to all kinds of platform input events.
562#[derive(Clone, Debug)]
563pub enum PlatformInput {
564    /// A key was pressed.
565    KeyDown(KeyDownEvent),
566    /// A key was released.
567    KeyUp(KeyUpEvent),
568    /// The keyboard modifiers were changed.
569    ModifiersChanged(ModifiersChangedEvent),
570    /// The mouse was pressed.
571    MouseDown(MouseDownEvent),
572    /// The mouse was released.
573    MouseUp(MouseUpEvent),
574    /// The mouse was moved.
575    MouseMove(MouseMoveEvent),
576    /// The mouse exited the window.
577    MouseExited(MouseExitEvent),
578    /// The scroll wheel was used.
579    ScrollWheel(ScrollWheelEvent),
580    /// Files were dragged and dropped onto the window.
581    FileDrop(FileDropEvent),
582}
583
584impl PlatformInput {
585    pub(crate) fn mouse_event(&self) -> Option<&dyn Any> {
586        match self {
587            PlatformInput::KeyDown { .. } => None,
588            PlatformInput::KeyUp { .. } => None,
589            PlatformInput::ModifiersChanged { .. } => None,
590            PlatformInput::MouseDown(event) => Some(event),
591            PlatformInput::MouseUp(event) => Some(event),
592            PlatformInput::MouseMove(event) => Some(event),
593            PlatformInput::MouseExited(event) => Some(event),
594            PlatformInput::ScrollWheel(event) => Some(event),
595            PlatformInput::FileDrop(event) => Some(event),
596        }
597    }
598
599    pub(crate) fn keyboard_event(&self) -> Option<&dyn Any> {
600        match self {
601            PlatformInput::KeyDown(event) => Some(event),
602            PlatformInput::KeyUp(event) => Some(event),
603            PlatformInput::ModifiersChanged(event) => Some(event),
604            PlatformInput::MouseDown(_) => None,
605            PlatformInput::MouseUp(_) => None,
606            PlatformInput::MouseMove(_) => None,
607            PlatformInput::MouseExited(_) => None,
608            PlatformInput::ScrollWheel(_) => None,
609            PlatformInput::FileDrop(_) => None,
610        }
611    }
612}
613
614#[cfg(test)]
615mod test {
616
617    use crate::{
618        self as gpui, AppContext as _, Context, FocusHandle, InteractiveElement, IntoElement,
619        KeyBinding, Keystroke, ParentElement, Render, TestAppContext, Window, div,
620    };
621
622    struct TestView {
623        saw_key_down: bool,
624        saw_action: bool,
625        focus_handle: FocusHandle,
626    }
627
628    actions!(test_only, [TestAction]);
629
630    impl Render for TestView {
631        fn render(&mut self, _: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
632            div().id("testview").child(
633                div()
634                    .key_context("parent")
635                    .on_key_down(cx.listener(|this, _, _, cx| {
636                        cx.stop_propagation();
637                        this.saw_key_down = true
638                    }))
639                    .on_action(cx.listener(|this: &mut TestView, _: &TestAction, _, _| {
640                        this.saw_action = true
641                    }))
642                    .child(
643                        div()
644                            .key_context("nested")
645                            .track_focus(&self.focus_handle)
646                            .into_element(),
647                    ),
648            )
649        }
650    }
651
652    #[gpui::test]
653    fn test_on_events(cx: &mut TestAppContext) {
654        let window = cx.update(|cx| {
655            cx.open_window(Default::default(), |_, cx| {
656                cx.new(|cx| TestView {
657                    saw_key_down: false,
658                    saw_action: false,
659                    focus_handle: cx.focus_handle(),
660                })
661            })
662            .unwrap()
663        });
664
665        cx.update(|cx| {
666            cx.bind_keys(vec![KeyBinding::new("ctrl-g", TestAction, Some("parent"))]);
667        });
668
669        window
670            .update(cx, |test_view, window, _cx| {
671                window.focus(&test_view.focus_handle)
672            })
673            .unwrap();
674
675        cx.dispatch_keystroke(*window, Keystroke::parse("a").unwrap());
676        cx.dispatch_keystroke(*window, Keystroke::parse("ctrl-g").unwrap());
677
678        window
679            .update(cx, |test_view, _, _| {
680                assert!(test_view.saw_key_down || test_view.saw_action);
681                assert!(test_view.saw_key_down);
682                assert!(test_view.saw_action);
683            })
684            .unwrap();
685    }
686}