right_click_menu.rs

  1use std::{cell::RefCell, rc::Rc};
  2
  3use gpui::{
  4    div, overlay, AnchorCorner, AnyElement, Bounds, DismissEvent, DispatchPhase, Element,
  5    ElementContext, ElementId, Hitbox, InteractiveElement, IntoElement, LayoutId, ManagedView,
  6    MouseButton, MouseDownEvent, ParentElement, Pixels, Point, View, VisualContext, WindowContext,
  7};
  8
  9pub struct RightClickMenu<M: ManagedView> {
 10    id: ElementId,
 11    child_builder: Option<Box<dyn FnOnce(bool) -> AnyElement + 'static>>,
 12    menu_builder: Option<Rc<dyn Fn(&mut WindowContext) -> View<M> + 'static>>,
 13    anchor: Option<AnchorCorner>,
 14    attach: Option<AnchorCorner>,
 15}
 16
 17impl<M: ManagedView> RightClickMenu<M> {
 18    pub fn menu(mut self, f: impl Fn(&mut WindowContext) -> View<M> + 'static) -> Self {
 19        self.menu_builder = Some(Rc::new(f));
 20        self
 21    }
 22
 23    pub fn trigger<E: IntoElement + 'static>(mut self, e: E) -> Self {
 24        self.child_builder = Some(Box::new(move |_| e.into_any_element()));
 25        self
 26    }
 27
 28    /// anchor defines which corner of the menu to anchor to the attachment point
 29    /// (by default the cursor position, but see attach)
 30    pub fn anchor(mut self, anchor: AnchorCorner) -> Self {
 31        self.anchor = Some(anchor);
 32        self
 33    }
 34
 35    /// attach defines which corner of the handle to attach the menu's anchor to
 36    pub fn attach(mut self, attach: AnchorCorner) -> Self {
 37        self.attach = Some(attach);
 38        self
 39    }
 40
 41    fn with_element_state<R>(
 42        &mut self,
 43        cx: &mut ElementContext,
 44        f: impl FnOnce(&mut Self, &mut MenuHandleElementState<M>, &mut ElementContext) -> R,
 45    ) -> R {
 46        cx.with_element_state::<MenuHandleElementState<M>, _>(
 47            Some(self.id.clone()),
 48            |element_state, cx| {
 49                let mut element_state = element_state.unwrap().unwrap_or_default();
 50                let result = f(self, &mut element_state, cx);
 51                (result, Some(element_state))
 52            },
 53        )
 54    }
 55}
 56
 57/// Creates a [`RightClickMenu`]
 58pub fn right_click_menu<M: ManagedView>(id: impl Into<ElementId>) -> RightClickMenu<M> {
 59    RightClickMenu {
 60        id: id.into(),
 61        child_builder: None,
 62        menu_builder: None,
 63        anchor: None,
 64        attach: None,
 65    }
 66}
 67
 68pub struct MenuHandleElementState<M> {
 69    menu: Rc<RefCell<Option<View<M>>>>,
 70    position: Rc<RefCell<Point<Pixels>>>,
 71}
 72
 73impl<M> Clone for MenuHandleElementState<M> {
 74    fn clone(&self) -> Self {
 75        Self {
 76            menu: Rc::clone(&self.menu),
 77            position: Rc::clone(&self.position),
 78        }
 79    }
 80}
 81
 82impl<M> Default for MenuHandleElementState<M> {
 83    fn default() -> Self {
 84        Self {
 85            menu: Rc::default(),
 86            position: Rc::default(),
 87        }
 88    }
 89}
 90
 91pub struct MenuHandleFrameState {
 92    child_layout_id: Option<LayoutId>,
 93    child_element: Option<AnyElement>,
 94    menu_element: Option<AnyElement>,
 95}
 96
 97impl<M: ManagedView> Element for RightClickMenu<M> {
 98    type BeforeLayout = MenuHandleFrameState;
 99    type AfterLayout = Hitbox;
100
101    fn before_layout(&mut self, cx: &mut ElementContext) -> (gpui::LayoutId, Self::BeforeLayout) {
102        self.with_element_state(cx, |this, element_state, cx| {
103            let mut menu_layout_id = None;
104
105            let menu_element = element_state.menu.borrow_mut().as_mut().map(|menu| {
106                let mut overlay = overlay().snap_to_window();
107                if let Some(anchor) = this.anchor {
108                    overlay = overlay.anchor(anchor);
109                }
110                overlay = overlay.position(*element_state.position.borrow());
111
112                let mut element = overlay
113                    .child(div().occlude().child(menu.clone()))
114                    .into_any();
115                menu_layout_id = Some(element.before_layout(cx));
116                element
117            });
118
119            let mut child_element = this
120                .child_builder
121                .take()
122                .map(|child_builder| (child_builder)(element_state.menu.borrow().is_some()));
123
124            let child_layout_id = child_element
125                .as_mut()
126                .map(|child_element| child_element.before_layout(cx));
127
128            let layout_id = cx.request_layout(
129                &gpui::Style::default(),
130                menu_layout_id.into_iter().chain(child_layout_id),
131            );
132
133            (
134                layout_id,
135                MenuHandleFrameState {
136                    child_element,
137                    child_layout_id,
138                    menu_element,
139                },
140            )
141        })
142    }
143
144    fn after_layout(
145        &mut self,
146        bounds: Bounds<Pixels>,
147        before_layout: &mut Self::BeforeLayout,
148        cx: &mut ElementContext,
149    ) -> Hitbox {
150        cx.with_element_id(Some(self.id.clone()), |cx| {
151            let hitbox = cx.insert_hitbox(bounds, false);
152
153            if let Some(child) = before_layout.child_element.as_mut() {
154                child.after_layout(cx);
155            }
156
157            if let Some(menu) = before_layout.menu_element.as_mut() {
158                menu.after_layout(cx);
159            }
160
161            hitbox
162        })
163    }
164
165    fn paint(
166        &mut self,
167        _bounds: Bounds<gpui::Pixels>,
168        before_layout: &mut Self::BeforeLayout,
169        hitbox: &mut Self::AfterLayout,
170        cx: &mut ElementContext,
171    ) {
172        self.with_element_state(cx, |this, element_state, cx| {
173            if let Some(mut child) = before_layout.child_element.take() {
174                child.paint(cx);
175            }
176
177            if let Some(mut menu) = before_layout.menu_element.take() {
178                menu.paint(cx);
179                return;
180            }
181
182            let Some(builder) = this.menu_builder.take() else {
183                return;
184            };
185
186            let attach = this.attach;
187            let menu = element_state.menu.clone();
188            let position = element_state.position.clone();
189            let child_layout_id = before_layout.child_layout_id;
190            let child_bounds = cx.layout_bounds(child_layout_id.unwrap());
191
192            let hitbox_id = hitbox.id;
193            cx.on_mouse_event(move |event: &MouseDownEvent, phase, cx| {
194                if phase == DispatchPhase::Bubble
195                    && event.button == MouseButton::Right
196                    && hitbox_id.is_hovered(cx)
197                {
198                    cx.stop_propagation();
199                    cx.prevent_default();
200
201                    let new_menu = (builder)(cx);
202                    let menu2 = menu.clone();
203                    let previous_focus_handle = cx.focused();
204
205                    cx.subscribe(&new_menu, move |modal, _: &DismissEvent, cx| {
206                        if modal.focus_handle(cx).contains_focused(cx) {
207                            if let Some(previous_focus_handle) = previous_focus_handle.as_ref() {
208                                cx.focus(previous_focus_handle);
209                            }
210                        }
211                        *menu2.borrow_mut() = None;
212                        cx.refresh();
213                    })
214                    .detach();
215                    cx.focus_view(&new_menu);
216                    *menu.borrow_mut() = Some(new_menu);
217                    *position.borrow_mut() = if child_layout_id.is_some() {
218                        if let Some(attach) = attach {
219                            attach.corner(child_bounds)
220                        } else {
221                            cx.mouse_position()
222                        }
223                    } else {
224                        cx.mouse_position()
225                    };
226                    cx.refresh();
227                }
228            });
229        })
230    }
231}
232
233impl<M: ManagedView> IntoElement for RightClickMenu<M> {
234    type Element = Self;
235
236    fn into_element(self) -> Self::Element {
237        self
238    }
239}