context_menu.rs

  1use gpui::{
  2    elements::*, geometry::vector::Vector2F, impl_internal_actions, keymap, platform::CursorStyle,
  3    Action, AppContext, Axis, Entity, MouseButton, MutableAppContext, RenderContext,
  4    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
 25//
 26pub enum ContextMenuItem {
 27    Item {
 28        label: String,
 29        action: Box<dyn Action>,
 30    },
 31    Separator,
 32}
 33
 34impl ContextMenuItem {
 35    pub fn item(label: impl ToString, action: impl 'static + Action) -> Self {
 36        Self::Item {
 37            label: label.to_string(),
 38            action: Box::new(action),
 39        }
 40    }
 41
 42    pub fn separator() -> Self {
 43        Self::Separator
 44    }
 45
 46    fn is_separator(&self) -> bool {
 47        matches!(self, Self::Separator)
 48    }
 49
 50    fn action_id(&self) -> Option<TypeId> {
 51        match self {
 52            ContextMenuItem::Item { action, .. } => Some(action.id()),
 53            ContextMenuItem::Separator => None,
 54        }
 55    }
 56}
 57
 58pub struct ContextMenu {
 59    show_count: usize,
 60    position: Vector2F,
 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) -> keymap::Context {
 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            .hoverable(true)
104            .fit_mode(OverlayFitMode::SnapToWindow)
105            .with_abs_position(self.position)
106            .boxed()
107    }
108
109    fn on_blur(&mut self, cx: &mut ViewContext<Self>) {
110        self.reset(cx);
111    }
112}
113
114impl ContextMenu {
115    pub fn new(cx: &mut ViewContext<Self>) -> Self {
116        Self {
117            show_count: 0,
118            position: Default::default(),
119            items: Default::default(),
120            selected_index: Default::default(),
121            visible: Default::default(),
122            previously_focused_view_id: Default::default(),
123            clicked: false,
124            _actions_observation: cx.observe_actions(Self::action_dispatched),
125        }
126    }
127
128    pub fn visible(&self) -> bool {
129        self.visible
130    }
131
132    fn action_dispatched(&mut self, action_id: TypeId, cx: &mut ViewContext<Self>) {
133        if let Some(ix) = self
134            .items
135            .iter()
136            .position(|item| item.action_id() == Some(action_id))
137        {
138            if self.clicked {
139                self.cancel(&Default::default(), cx);
140            } else {
141                self.selected_index = Some(ix);
142                cx.notify();
143                cx.spawn(|this, mut cx| async move {
144                    cx.background().timer(Duration::from_millis(50)).await;
145                    this.update(&mut cx, |this, cx| this.cancel(&Default::default(), cx));
146                })
147                .detach();
148            }
149        }
150    }
151
152    fn clicked(&mut self, _: &Clicked, _: &mut ViewContext<Self>) {
153        self.clicked = true;
154    }
155
156    fn confirm(&mut self, _: &Confirm, cx: &mut ViewContext<Self>) {
157        if let Some(ix) = self.selected_index {
158            if let Some(ContextMenuItem::Item { action, .. }) = self.items.get(ix) {
159                let window_id = cx.window_id();
160                let view_id = cx.view_id();
161                cx.dispatch_action_at(window_id, view_id, action.as_ref());
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        position: Vector2F,
232        items: impl IntoIterator<Item = ContextMenuItem>,
233        cx: &mut ViewContext<Self>,
234    ) {
235        let mut items = items.into_iter().peekable();
236        if items.peek().is_some() {
237            self.items = items.collect();
238            self.position = position;
239            self.visible = true;
240            self.show_count += 1;
241            if !cx.is_self_focused() {
242                self.previously_focused_view_id = cx.focused_view_id(cx.window_id());
243            }
244            cx.focus_self();
245        } else {
246            self.visible = false;
247        }
248        cx.notify();
249    }
250
251    fn render_menu_for_measurement(&self, cx: &mut RenderContext<Self>) -> impl Element {
252        let style = cx.global::<Settings>().theme.context_menu.clone();
253        Flex::row()
254            .with_child(
255                Flex::column()
256                    .with_children(self.items.iter().enumerate().map(|(ix, item)| {
257                        match item {
258                            ContextMenuItem::Item { label, .. } => {
259                                let style = style
260                                    .item
261                                    .style_for(Default::default(), Some(ix) == self.selected_index);
262
263                                Label::new(label.to_string(), style.label.clone())
264                                    .contained()
265                                    .with_style(style.container)
266                                    .boxed()
267                            }
268                            ContextMenuItem::Separator => Empty::new()
269                                .collapsed()
270                                .contained()
271                                .with_style(style.separator)
272                                .constrained()
273                                .with_height(1.)
274                                .boxed(),
275                        }
276                    }))
277                    .boxed(),
278            )
279            .with_child(
280                Flex::column()
281                    .with_children(self.items.iter().enumerate().map(|(ix, item)| {
282                        match item {
283                            ContextMenuItem::Item { action, .. } => {
284                                let style = style
285                                    .item
286                                    .style_for(Default::default(), Some(ix) == self.selected_index);
287                                KeystrokeLabel::new(
288                                    action.boxed_clone(),
289                                    style.keystroke.container,
290                                    style.keystroke.text.clone(),
291                                )
292                                .boxed()
293                            }
294                            ContextMenuItem::Separator => Empty::new()
295                                .collapsed()
296                                .constrained()
297                                .with_height(1.)
298                                .contained()
299                                .with_style(style.separator)
300                                .boxed(),
301                        }
302                    }))
303                    .contained()
304                    .with_margin_left(style.keystroke_margin)
305                    .boxed(),
306            )
307            .contained()
308            .with_style(style.container)
309    }
310
311    fn render_menu(&self, cx: &mut RenderContext<Self>) -> impl Element {
312        enum Menu {}
313        enum MenuItem {}
314        let style = cx.global::<Settings>().theme.context_menu.clone();
315        MouseEventHandler::new::<Menu, _, _>(0, cx, |_, cx| {
316            Flex::column()
317                .with_children(self.items.iter().enumerate().map(|(ix, item)| {
318                    match item {
319                        ContextMenuItem::Item { label, action } => {
320                            let action = action.boxed_clone();
321                            MouseEventHandler::new::<MenuItem, _, _>(ix, cx, |state, _| {
322                                let style =
323                                    style.item.style_for(state, Some(ix) == self.selected_index);
324
325                                Flex::row()
326                                    .with_child(
327                                        Label::new(label.to_string(), style.label.clone())
328                                            .contained()
329                                            .boxed(),
330                                    )
331                                    .with_child({
332                                        KeystrokeLabel::new(
333                                            action.boxed_clone(),
334                                            style.keystroke.container,
335                                            style.keystroke.text.clone(),
336                                        )
337                                        .flex_float()
338                                        .boxed()
339                                    })
340                                    .contained()
341                                    .with_style(style.container)
342                                    .boxed()
343                            })
344                            .with_cursor_style(CursorStyle::PointingHand)
345                            .on_click(MouseButton::Left, move |_, cx| {
346                                cx.dispatch_action(Clicked);
347                                cx.dispatch_any_action(action.boxed_clone());
348                            })
349                            .boxed()
350                        }
351                        ContextMenuItem::Separator => Empty::new()
352                            .constrained()
353                            .with_height(1.)
354                            .contained()
355                            .with_style(style.separator)
356                            .boxed(),
357                    }
358                }))
359                .contained()
360                .with_style(style.container)
361                .boxed()
362        })
363        .on_down_out(MouseButton::Left, |_, cx| cx.dispatch_action(Cancel))
364        .on_down_out(MouseButton::Right, |_, cx| cx.dispatch_action(Cancel))
365    }
366}