context_menu.rs

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