context_menu.rs

  1use gpui::{
  2    elements::*, geometry::vector::Vector2F, impl_internal_actions, keymap_matcher::KeymapContext,
  3    platform::CursorStyle, Action, AnyViewHandle, AppContext, Axis, Entity, MouseButton,
  4    MutableAppContext, RenderContext, SizeConstraint, Subscription, View, ViewContext,
  5};
  6use menu::*;
  7use settings::Settings;
  8use std::{any::TypeId, time::Duration};
  9
 10#[derive(Copy, Clone, PartialEq)]
 11struct Clicked;
 12
 13impl_internal_actions!(context_menu, [Clicked]);
 14
 15pub fn init(cx: &mut MutableAppContext) {
 16    cx.add_action(ContextMenu::select_first);
 17    cx.add_action(ContextMenu::select_last);
 18    cx.add_action(ContextMenu::select_next);
 19    cx.add_action(ContextMenu::select_prev);
 20    cx.add_action(ContextMenu::clicked);
 21    cx.add_action(ContextMenu::confirm);
 22    cx.add_action(ContextMenu::cancel);
 23}
 24
 25pub enum ContextMenuItem {
 26    Item {
 27        label: String,
 28        action: Box<dyn Action>,
 29    },
 30    Separator,
 31}
 32
 33impl ContextMenuItem {
 34    pub fn item(label: impl ToString, action: impl 'static + Action) -> Self {
 35        Self::Item {
 36            label: label.to_string(),
 37            action: Box::new(action),
 38        }
 39    }
 40
 41    pub fn separator() -> Self {
 42        Self::Separator
 43    }
 44
 45    fn is_separator(&self) -> bool {
 46        matches!(self, Self::Separator)
 47    }
 48
 49    fn action_id(&self) -> Option<TypeId> {
 50        match self {
 51            ContextMenuItem::Item { action, .. } => Some(action.id()),
 52            ContextMenuItem::Separator => None,
 53        }
 54    }
 55}
 56
 57pub struct ContextMenu {
 58    show_count: usize,
 59    anchor_position: Vector2F,
 60    anchor_corner: AnchorCorner,
 61    items: Vec<ContextMenuItem>,
 62    selected_index: Option<usize>,
 63    visible: bool,
 64    previously_focused_view_id: Option<usize>,
 65    clicked: bool,
 66    _actions_observation: Subscription,
 67}
 68
 69impl Entity for ContextMenu {
 70    type Event = ();
 71}
 72
 73impl View for ContextMenu {
 74    fn ui_name() -> &'static str {
 75        "ContextMenu"
 76    }
 77
 78    fn keymap_context(&self, _: &AppContext) -> KeymapContext {
 79        let mut cx = Self::default_keymap_context();
 80        cx.set.insert("menu".into());
 81        cx
 82    }
 83
 84    fn render(&mut self, cx: &mut RenderContext<Self>) -> ElementBox {
 85        if !self.visible {
 86            return Empty::new().boxed();
 87        }
 88
 89        // Render the menu once at minimum width.
 90        let mut collapsed_menu = self.render_menu_for_measurement(cx).boxed();
 91        let expanded_menu = self
 92            .render_menu(cx)
 93            .constrained()
 94            .dynamically(move |constraint, cx| {
 95                SizeConstraint::strict_along(
 96                    Axis::Horizontal,
 97                    collapsed_menu.layout(constraint, cx).x(),
 98                )
 99            })
100            .boxed();
101
102        Overlay::new(expanded_menu)
103            .with_hoverable(true)
104            .with_fit_mode(OverlayFitMode::SnapToWindow)
105            .with_anchor_position(self.anchor_position)
106            .with_anchor_corner(self.anchor_corner)
107            .boxed()
108    }
109
110    fn focus_out(&mut self, _: AnyViewHandle, cx: &mut ViewContext<Self>) {
111        self.reset(cx);
112    }
113}
114
115impl ContextMenu {
116    pub fn new(cx: &mut ViewContext<Self>) -> Self {
117        Self {
118            show_count: 0,
119            anchor_position: Default::default(),
120            anchor_corner: AnchorCorner::TopLeft,
121            items: Default::default(),
122            selected_index: Default::default(),
123            visible: Default::default(),
124            previously_focused_view_id: Default::default(),
125            clicked: false,
126            _actions_observation: cx.observe_actions(Self::action_dispatched),
127        }
128    }
129
130    pub fn visible(&self) -> bool {
131        self.visible
132    }
133
134    fn action_dispatched(&mut self, action_id: TypeId, cx: &mut ViewContext<Self>) {
135        if let Some(ix) = self
136            .items
137            .iter()
138            .position(|item| item.action_id() == Some(action_id))
139        {
140            if self.clicked {
141                self.cancel(&Default::default(), cx);
142            } else {
143                self.selected_index = Some(ix);
144                cx.notify();
145                cx.spawn(|this, mut cx| async move {
146                    cx.background().timer(Duration::from_millis(50)).await;
147                    this.update(&mut cx, |this, cx| this.cancel(&Default::default(), cx));
148                })
149                .detach();
150            }
151        }
152    }
153
154    fn clicked(&mut self, _: &Clicked, _: &mut ViewContext<Self>) {
155        self.clicked = true;
156    }
157
158    fn confirm(&mut self, _: &Confirm, cx: &mut ViewContext<Self>) {
159        if let Some(ix) = self.selected_index {
160            if let Some(ContextMenuItem::Item { action, .. }) = self.items.get(ix) {
161                cx.dispatch_any_action(action.boxed_clone());
162                self.reset(cx);
163            }
164        }
165    }
166
167    fn cancel(&mut self, _: &Cancel, cx: &mut ViewContext<Self>) {
168        self.reset(cx);
169        let show_count = self.show_count;
170        cx.defer(move |this, cx| {
171            if cx.handle().is_focused(cx) && this.show_count == show_count {
172                let window_id = cx.window_id();
173                (**cx).focus(window_id, this.previously_focused_view_id.take());
174            }
175        });
176    }
177
178    fn reset(&mut self, cx: &mut ViewContext<Self>) {
179        self.items.clear();
180        self.visible = false;
181        self.selected_index.take();
182        self.clicked = false;
183        cx.notify();
184    }
185
186    fn select_first(&mut self, _: &SelectFirst, cx: &mut ViewContext<Self>) {
187        self.selected_index = self.items.iter().position(|item| !item.is_separator());
188        cx.notify();
189    }
190
191    fn select_last(&mut self, _: &SelectLast, cx: &mut ViewContext<Self>) {
192        for (ix, item) in self.items.iter().enumerate().rev() {
193            if !item.is_separator() {
194                self.selected_index = Some(ix);
195                cx.notify();
196                break;
197            }
198        }
199    }
200
201    fn select_next(&mut self, _: &SelectNext, cx: &mut ViewContext<Self>) {
202        if let Some(ix) = self.selected_index {
203            for (ix, item) in self.items.iter().enumerate().skip(ix + 1) {
204                if !item.is_separator() {
205                    self.selected_index = Some(ix);
206                    cx.notify();
207                    break;
208                }
209            }
210        } else {
211            self.select_first(&Default::default(), cx);
212        }
213    }
214
215    fn select_prev(&mut self, _: &SelectPrev, cx: &mut ViewContext<Self>) {
216        if let Some(ix) = self.selected_index {
217            for (ix, item) in self.items.iter().enumerate().take(ix).rev() {
218                if !item.is_separator() {
219                    self.selected_index = Some(ix);
220                    cx.notify();
221                    break;
222                }
223            }
224        } else {
225            self.select_last(&Default::default(), cx);
226        }
227    }
228
229    pub fn show(
230        &mut self,
231        anchor_position: Vector2F,
232        anchor_corner: AnchorCorner,
233        items: impl IntoIterator<Item = ContextMenuItem>,
234        cx: &mut ViewContext<Self>,
235    ) {
236        let mut items = items.into_iter().peekable();
237        if items.peek().is_some() {
238            self.items = items.collect();
239            self.anchor_position = anchor_position;
240            self.anchor_corner = anchor_corner;
241            self.visible = true;
242            self.show_count += 1;
243            if !cx.is_self_focused() {
244                self.previously_focused_view_id = cx.focused_view_id(cx.window_id());
245            }
246            cx.focus_self();
247        } else {
248            self.visible = false;
249        }
250        cx.notify();
251    }
252
253    fn render_menu_for_measurement(&self, cx: &mut RenderContext<Self>) -> impl Element {
254        let style = cx.global::<Settings>().theme.context_menu.clone();
255        Flex::row()
256            .with_child(
257                Flex::column()
258                    .with_children(self.items.iter().enumerate().map(|(ix, item)| {
259                        match item {
260                            ContextMenuItem::Item { label, .. } => {
261                                let style = style.item.style_for(
262                                    &mut Default::default(),
263                                    Some(ix) == self.selected_index,
264                                );
265
266                                Label::new(label.to_string(), style.label.clone())
267                                    .contained()
268                                    .with_style(style.container)
269                                    .boxed()
270                            }
271                            ContextMenuItem::Separator => Empty::new()
272                                .collapsed()
273                                .contained()
274                                .with_style(style.separator)
275                                .constrained()
276                                .with_height(1.)
277                                .boxed(),
278                        }
279                    }))
280                    .boxed(),
281            )
282            .with_child(
283                Flex::column()
284                    .with_children(self.items.iter().enumerate().map(|(ix, item)| {
285                        match item {
286                            ContextMenuItem::Item { action, .. } => {
287                                let style = style.item.style_for(
288                                    &mut Default::default(),
289                                    Some(ix) == self.selected_index,
290                                );
291                                KeystrokeLabel::new(
292                                    action.boxed_clone(),
293                                    style.keystroke.container,
294                                    style.keystroke.text.clone(),
295                                )
296                                .boxed()
297                            }
298                            ContextMenuItem::Separator => Empty::new()
299                                .collapsed()
300                                .constrained()
301                                .with_height(1.)
302                                .contained()
303                                .with_style(style.separator)
304                                .boxed(),
305                        }
306                    }))
307                    .contained()
308                    .with_margin_left(style.keystroke_margin)
309                    .boxed(),
310            )
311            .contained()
312            .with_style(style.container)
313    }
314
315    fn render_menu(&self, cx: &mut RenderContext<Self>) -> impl Element {
316        enum Menu {}
317        enum MenuItem {}
318
319        let style = cx.global::<Settings>().theme.context_menu.clone();
320
321        MouseEventHandler::<Menu>::new(0, cx, |_, cx| {
322            Flex::column()
323                .with_children(self.items.iter().enumerate().map(|(ix, item)| {
324                    match item {
325                        ContextMenuItem::Item { label, action } => {
326                            let action = action.boxed_clone();
327
328                            MouseEventHandler::<MenuItem>::new(ix, cx, |state, _| {
329                                let style =
330                                    style.item.style_for(state, Some(ix) == self.selected_index);
331
332                                Flex::row()
333                                    .with_child(
334                                        Label::new(label.to_string(), style.label.clone())
335                                            .contained()
336                                            .boxed(),
337                                    )
338                                    .with_child({
339                                        KeystrokeLabel::new(
340                                            action.boxed_clone(),
341                                            style.keystroke.container,
342                                            style.keystroke.text.clone(),
343                                        )
344                                        .flex_float()
345                                        .boxed()
346                                    })
347                                    .contained()
348                                    .with_style(style.container)
349                                    .boxed()
350                            })
351                            .with_cursor_style(CursorStyle::PointingHand)
352                            .on_click(MouseButton::Left, move |_, cx| {
353                                cx.dispatch_action(Clicked);
354                                cx.dispatch_any_action(action.boxed_clone());
355                            })
356                            .on_drag(MouseButton::Left, |_, _| {})
357                            .boxed()
358                        }
359                        ContextMenuItem::Separator => Empty::new()
360                            .constrained()
361                            .with_height(1.)
362                            .contained()
363                            .with_style(style.separator)
364                            .boxed(),
365                    }
366                }))
367                .contained()
368                .with_style(style.container)
369                .boxed()
370        })
371        .on_down_out(MouseButton::Left, |_, cx| cx.dispatch_action(Cancel))
372        .on_down_out(MouseButton::Right, |_, cx| cx.dispatch_action(Cancel))
373    }
374}