context_menu.rs

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