context_menu.rs

  1use crate::{
  2    h_flex, prelude::*, v_flex, Icon, IconName, KeyBinding, Label, List, ListItem, ListSeparator,
  3    ListSubHeader,
  4};
  5use gpui::{
  6    px, Action, AnyElement, AppContext, DismissEvent, EventEmitter, FocusHandle, FocusableView,
  7    IntoElement, Render, Subscription, View, VisualContext,
  8};
  9use menu::{SelectFirst, SelectLast, SelectNext, SelectPrev};
 10use std::{rc::Rc, time::Duration};
 11
 12enum ContextMenuItem {
 13    Separator,
 14    Header(SharedString),
 15    Entry {
 16        label: SharedString,
 17        icon: Option<IconName>,
 18        handler: Rc<dyn Fn(&mut WindowContext)>,
 19        action: Option<Box<dyn Action>>,
 20    },
 21    CustomEntry {
 22        entry_render: Box<dyn Fn(&mut WindowContext) -> AnyElement>,
 23        handler: Rc<dyn Fn(&mut WindowContext)>,
 24    },
 25}
 26
 27pub struct ContextMenu {
 28    items: Vec<ContextMenuItem>,
 29    focus_handle: FocusHandle,
 30    selected_index: Option<usize>,
 31    delayed: bool,
 32    clicked: bool,
 33    _on_blur_subscription: Subscription,
 34}
 35
 36impl FocusableView for ContextMenu {
 37    fn focus_handle(&self, _cx: &AppContext) -> FocusHandle {
 38        self.focus_handle.clone()
 39    }
 40}
 41
 42impl EventEmitter<DismissEvent> for ContextMenu {}
 43
 44impl ContextMenu {
 45    pub fn build(
 46        cx: &mut WindowContext,
 47        f: impl FnOnce(Self, &mut WindowContext) -> Self,
 48    ) -> View<Self> {
 49        cx.new_view(|cx| {
 50            let focus_handle = cx.focus_handle();
 51            let _on_blur_subscription = cx.on_blur(&focus_handle, |this: &mut ContextMenu, cx| {
 52                this.cancel(&menu::Cancel, cx)
 53            });
 54            cx.refresh();
 55            f(
 56                Self {
 57                    items: Default::default(),
 58                    focus_handle,
 59                    selected_index: None,
 60                    delayed: false,
 61                    clicked: false,
 62                    _on_blur_subscription,
 63                },
 64                cx,
 65            )
 66        })
 67    }
 68
 69    pub fn header(mut self, title: impl Into<SharedString>) -> Self {
 70        self.items.push(ContextMenuItem::Header(title.into()));
 71        self
 72    }
 73
 74    pub fn separator(mut self) -> Self {
 75        self.items.push(ContextMenuItem::Separator);
 76        self
 77    }
 78
 79    pub fn entry(
 80        mut self,
 81        label: impl Into<SharedString>,
 82        action: Option<Box<dyn Action>>,
 83        handler: impl Fn(&mut WindowContext) + 'static,
 84    ) -> Self {
 85        self.items.push(ContextMenuItem::Entry {
 86            label: label.into(),
 87            handler: Rc::new(handler),
 88            icon: None,
 89            action,
 90        });
 91        self
 92    }
 93
 94    pub fn custom_entry(
 95        mut self,
 96        entry_render: impl Fn(&mut WindowContext) -> AnyElement + 'static,
 97        handler: impl Fn(&mut WindowContext) + 'static,
 98    ) -> Self {
 99        self.items.push(ContextMenuItem::CustomEntry {
100            entry_render: Box::new(entry_render),
101            handler: Rc::new(handler),
102        });
103        self
104    }
105
106    pub fn action(mut self, label: impl Into<SharedString>, action: Box<dyn Action>) -> Self {
107        self.items.push(ContextMenuItem::Entry {
108            label: label.into(),
109            action: Some(action.boxed_clone()),
110            handler: Rc::new(move |cx| cx.dispatch_action(action.boxed_clone())),
111            icon: None,
112        });
113        self
114    }
115
116    pub fn link(mut self, label: impl Into<SharedString>, action: Box<dyn Action>) -> Self {
117        self.items.push(ContextMenuItem::Entry {
118            label: label.into(),
119            action: Some(action.boxed_clone()),
120            handler: Rc::new(move |cx| cx.dispatch_action(action.boxed_clone())),
121            icon: Some(IconName::Link),
122        });
123        self
124    }
125
126    pub fn confirm(&mut self, _: &menu::Confirm, cx: &mut ViewContext<Self>) {
127        match self.selected_index.and_then(|ix| self.items.get(ix)) {
128            Some(
129                ContextMenuItem::Entry { handler, .. }
130                | ContextMenuItem::CustomEntry { handler, .. },
131            ) => (handler)(cx),
132            _ => {}
133        }
134
135        cx.emit(DismissEvent);
136    }
137
138    pub fn cancel(&mut self, _: &menu::Cancel, cx: &mut ViewContext<Self>) {
139        cx.emit(DismissEvent);
140        cx.emit(DismissEvent);
141    }
142
143    fn select_first(&mut self, _: &SelectFirst, cx: &mut ViewContext<Self>) {
144        self.selected_index = self.items.iter().position(|item| item.is_selectable());
145        cx.notify();
146    }
147
148    pub fn select_last(&mut self) -> Option<usize> {
149        for (ix, item) in self.items.iter().enumerate().rev() {
150            if item.is_selectable() {
151                self.selected_index = Some(ix);
152                return Some(ix);
153            }
154        }
155        None
156    }
157
158    fn handle_select_last(&mut self, _: &SelectLast, cx: &mut ViewContext<Self>) {
159        if self.select_last().is_some() {
160            cx.notify();
161        }
162    }
163
164    fn select_next(&mut self, _: &SelectNext, cx: &mut ViewContext<Self>) {
165        if let Some(ix) = self.selected_index {
166            for (ix, item) in self.items.iter().enumerate().skip(ix + 1) {
167                if item.is_selectable() {
168                    self.selected_index = Some(ix);
169                    cx.notify();
170                    break;
171                }
172            }
173        } else {
174            self.select_first(&Default::default(), cx);
175        }
176    }
177
178    pub fn select_prev(&mut self, _: &SelectPrev, cx: &mut ViewContext<Self>) {
179        if let Some(ix) = self.selected_index {
180            for (ix, item) in self.items.iter().enumerate().take(ix).rev() {
181                if item.is_selectable() {
182                    self.selected_index = Some(ix);
183                    cx.notify();
184                    break;
185                }
186            }
187        } else {
188            self.handle_select_last(&Default::default(), cx);
189        }
190    }
191
192    pub fn on_action_dispatch(&mut self, dispatched: &Box<dyn Action>, cx: &mut ViewContext<Self>) {
193        if self.clicked {
194            cx.propagate();
195            return;
196        }
197
198        if let Some(ix) = self.items.iter().position(|item| {
199            if let ContextMenuItem::Entry {
200                action: Some(action),
201                ..
202            } = item
203            {
204                action.partial_eq(&**dispatched)
205            } else {
206                false
207            }
208        }) {
209            self.selected_index = Some(ix);
210            self.delayed = true;
211            cx.notify();
212            let action = dispatched.boxed_clone();
213            cx.spawn(|this, mut cx| async move {
214                cx.background_executor()
215                    .timer(Duration::from_millis(50))
216                    .await;
217                this.update(&mut cx, |this, cx| {
218                    cx.dispatch_action(action);
219                    this.cancel(&menu::Cancel, cx)
220                })
221            })
222            .detach_and_log_err(cx);
223        } else {
224            cx.propagate()
225        }
226    }
227}
228
229impl ContextMenuItem {
230    fn is_selectable(&self) -> bool {
231        matches!(self, Self::Entry { .. } | Self::CustomEntry { .. })
232    }
233}
234
235impl Render for ContextMenu {
236    fn render(&mut self, cx: &mut ViewContext<Self>) -> impl IntoElement {
237        div().elevation_2(cx).flex().flex_row().child(
238            v_flex()
239                .min_w(px(200.))
240                .track_focus(&self.focus_handle)
241                .on_mouse_down_out(cx.listener(|this, _, cx| this.cancel(&menu::Cancel, cx)))
242                .key_context("menu")
243                .on_action(cx.listener(ContextMenu::select_first))
244                .on_action(cx.listener(ContextMenu::handle_select_last))
245                .on_action(cx.listener(ContextMenu::select_next))
246                .on_action(cx.listener(ContextMenu::select_prev))
247                .on_action(cx.listener(ContextMenu::confirm))
248                .on_action(cx.listener(ContextMenu::cancel))
249                .when(!self.delayed, |mut el| {
250                    for item in self.items.iter() {
251                        if let ContextMenuItem::Entry {
252                            action: Some(action),
253                            ..
254                        } = item
255                        {
256                            el = el.on_boxed_action(
257                                &**action,
258                                cx.listener(ContextMenu::on_action_dispatch),
259                            );
260                        }
261                    }
262                    el
263                })
264                .flex_none()
265                .child(List::new().children(self.items.iter_mut().enumerate().map(
266                    |(ix, item)| match item {
267                        ContextMenuItem::Separator => ListSeparator.into_any_element(),
268                        ContextMenuItem::Header(header) => {
269                            ListSubHeader::new(header.clone()).into_any_element()
270                        }
271                        ContextMenuItem::Entry {
272                            label,
273                            handler,
274                            icon,
275                            action,
276                        } => {
277                            let handler = handler.clone();
278                            let menu = cx.view().downgrade();
279
280                            let label_element = if let Some(icon) = icon {
281                                h_flex()
282                                    .gap_1()
283                                    .child(Label::new(label.clone()))
284                                    .child(Icon::new(*icon))
285                                    .into_any_element()
286                            } else {
287                                Label::new(label.clone()).into_any_element()
288                            };
289
290                            ListItem::new(ix)
291                                .inset(true)
292                                .selected(Some(ix) == self.selected_index)
293                                .on_click(move |_, cx| {
294                                    handler(cx);
295                                    menu.update(cx, |menu, cx| {
296                                        menu.clicked = true;
297                                        cx.emit(DismissEvent);
298                                    })
299                                    .ok();
300                                })
301                                .child(
302                                    h_flex()
303                                        .w_full()
304                                        .justify_between()
305                                        .child(label_element)
306                                        .children(action.as_ref().and_then(|action| {
307                                            KeyBinding::for_action(&**action, cx)
308                                                .map(|binding| div().ml_1().child(binding))
309                                        })),
310                                )
311                                .into_any_element()
312                        }
313                        ContextMenuItem::CustomEntry {
314                            entry_render,
315                            handler,
316                        } => {
317                            let handler = handler.clone();
318                            let menu = cx.view().downgrade();
319                            ListItem::new(ix)
320                                .inset(true)
321                                .selected(Some(ix) == self.selected_index)
322                                .on_click(move |_, cx| {
323                                    handler(cx);
324                                    menu.update(cx, |menu, cx| {
325                                        menu.clicked = true;
326                                        cx.emit(DismissEvent);
327                                    })
328                                    .ok();
329                                })
330                                .child(entry_render(cx))
331                                .into_any_element()
332                        }
333                    },
334                ))),
335        )
336    }
337}