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                cx.dispatch_any_action(action.boxed_clone());
160                self.reset(cx);
161            }
162        }
163    }
164
165    fn cancel(&mut self, _: &Cancel, cx: &mut ViewContext<Self>) {
166        self.reset(cx);
167        let show_count = self.show_count;
168        cx.defer(move |this, cx| {
169            if cx.handle().is_focused(cx) && this.show_count == show_count {
170                let window_id = cx.window_id();
171                (**cx).focus(window_id, this.previously_focused_view_id.take());
172            }
173        });
174    }
175
176    fn reset(&mut self, cx: &mut ViewContext<Self>) {
177        self.items.clear();
178        self.visible = false;
179        self.selected_index.take();
180        self.clicked = false;
181        cx.notify();
182    }
183
184    fn select_first(&mut self, _: &SelectFirst, cx: &mut ViewContext<Self>) {
185        self.selected_index = self.items.iter().position(|item| !item.is_separator());
186        cx.notify();
187    }
188
189    fn select_last(&mut self, _: &SelectLast, cx: &mut ViewContext<Self>) {
190        for (ix, item) in self.items.iter().enumerate().rev() {
191            if !item.is_separator() {
192                self.selected_index = Some(ix);
193                cx.notify();
194                break;
195            }
196        }
197    }
198
199    fn select_next(&mut self, _: &SelectNext, cx: &mut ViewContext<Self>) {
200        if let Some(ix) = self.selected_index {
201            for (ix, item) in self.items.iter().enumerate().skip(ix + 1) {
202                if !item.is_separator() {
203                    self.selected_index = Some(ix);
204                    cx.notify();
205                    break;
206                }
207            }
208        } else {
209            self.select_first(&Default::default(), cx);
210        }
211    }
212
213    fn select_prev(&mut self, _: &SelectPrev, cx: &mut ViewContext<Self>) {
214        if let Some(ix) = self.selected_index {
215            for (ix, item) in self.items.iter().enumerate().take(ix).rev() {
216                if !item.is_separator() {
217                    self.selected_index = Some(ix);
218                    cx.notify();
219                    break;
220                }
221            }
222        } else {
223            self.select_last(&Default::default(), cx);
224        }
225    }
226
227    pub fn show(
228        &mut self,
229        position: Vector2F,
230        items: impl IntoIterator<Item = ContextMenuItem>,
231        cx: &mut ViewContext<Self>,
232    ) {
233        let mut items = items.into_iter().peekable();
234        if items.peek().is_some() {
235            self.items = items.collect();
236            self.position = position;
237            self.visible = true;
238            self.show_count += 1;
239            if !cx.is_self_focused() {
240                self.previously_focused_view_id = cx.focused_view_id(cx.window_id());
241            }
242            cx.focus_self();
243        } else {
244            self.visible = false;
245        }
246        cx.notify();
247    }
248
249    fn render_menu_for_measurement(&self, cx: &mut RenderContext<Self>) -> impl Element {
250        let style = cx.global::<Settings>().theme.context_menu.clone();
251        Flex::row()
252            .with_child(
253                Flex::column()
254                    .with_children(self.items.iter().enumerate().map(|(ix, item)| {
255                        match item {
256                            ContextMenuItem::Item { label, .. } => {
257                                let style = style
258                                    .item
259                                    .style_for(Default::default(), Some(ix) == self.selected_index);
260
261                                Label::new(label.to_string(), style.label.clone())
262                                    .contained()
263                                    .with_style(style.container)
264                                    .boxed()
265                            }
266                            ContextMenuItem::Separator => Empty::new()
267                                .collapsed()
268                                .contained()
269                                .with_style(style.separator)
270                                .constrained()
271                                .with_height(1.)
272                                .boxed(),
273                        }
274                    }))
275                    .boxed(),
276            )
277            .with_child(
278                Flex::column()
279                    .with_children(self.items.iter().enumerate().map(|(ix, item)| {
280                        match item {
281                            ContextMenuItem::Item { action, .. } => {
282                                let style = style
283                                    .item
284                                    .style_for(Default::default(), Some(ix) == self.selected_index);
285                                KeystrokeLabel::new(
286                                    action.boxed_clone(),
287                                    style.keystroke.container,
288                                    style.keystroke.text.clone(),
289                                )
290                                .boxed()
291                            }
292                            ContextMenuItem::Separator => Empty::new()
293                                .collapsed()
294                                .constrained()
295                                .with_height(1.)
296                                .contained()
297                                .with_style(style.separator)
298                                .boxed(),
299                        }
300                    }))
301                    .contained()
302                    .with_margin_left(style.keystroke_margin)
303                    .boxed(),
304            )
305            .contained()
306            .with_style(style.container)
307    }
308
309    fn render_menu(&self, cx: &mut RenderContext<Self>) -> impl Element {
310        enum Menu {}
311        enum MenuItem {}
312        let style = cx.global::<Settings>().theme.context_menu.clone();
313        MouseEventHandler::new::<Menu, _, _>(0, cx, |_, cx| {
314            Flex::column()
315                .with_children(self.items.iter().enumerate().map(|(ix, item)| {
316                    match item {
317                        ContextMenuItem::Item { label, action } => {
318                            let action = action.boxed_clone();
319                            MouseEventHandler::new::<MenuItem, _, _>(ix, cx, |state, _| {
320                                let style =
321                                    style.item.style_for(state, Some(ix) == self.selected_index);
322
323                                Flex::row()
324                                    .with_child(
325                                        Label::new(label.to_string(), style.label.clone())
326                                            .contained()
327                                            .boxed(),
328                                    )
329                                    .with_child({
330                                        KeystrokeLabel::new(
331                                            action.boxed_clone(),
332                                            style.keystroke.container,
333                                            style.keystroke.text.clone(),
334                                        )
335                                        .flex_float()
336                                        .boxed()
337                                    })
338                                    .contained()
339                                    .with_style(style.container)
340                                    .boxed()
341                            })
342                            .with_cursor_style(CursorStyle::PointingHand)
343                            .on_click(MouseButton::Left, move |_, cx| {
344                                cx.dispatch_action(Clicked);
345                                cx.dispatch_any_action(action.boxed_clone());
346                            })
347                            .boxed()
348                        }
349                        ContextMenuItem::Separator => Empty::new()
350                            .constrained()
351                            .with_height(1.)
352                            .contained()
353                            .with_style(style.separator)
354                            .boxed(),
355                    }
356                }))
357                .contained()
358                .with_style(style.container)
359                .boxed()
360        })
361        .on_down_out(MouseButton::Left, |_, cx| cx.dispatch_action(Cancel))
362        .on_down_out(MouseButton::Right, |_, cx| cx.dispatch_action(Cancel))
363    }
364}