right_click_menu.rs

  1use std::{cell::RefCell, rc::Rc};
  2
  3use gpui::{
  4    anchored, deferred, div, AnchorCorner, AnyElement, Bounds, DismissEvent, DispatchPhase,
  5    Element, 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 WindowContext,
 44        f: impl FnOnce(&mut Self, &mut MenuHandleElementState<M>, &mut WindowContext) -> 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 RequestLayoutState {
 92    child_layout_id: Option<LayoutId>,
 93    child_element: Option<AnyElement>,
 94    menu_element: Option<AnyElement>,
 95}
 96
 97pub struct PrepaintState {
 98    hitbox: Hitbox,
 99    child_bounds: Option<Bounds<Pixels>>,
100}
101
102impl<M: ManagedView> Element for RightClickMenu<M> {
103    type RequestLayoutState = RequestLayoutState;
104    type PrepaintState = PrepaintState;
105
106    fn request_layout(
107        &mut self,
108        cx: &mut WindowContext,
109    ) -> (gpui::LayoutId, Self::RequestLayoutState) {
110        self.with_element_state(cx, |this, element_state, cx| {
111            let mut menu_layout_id = None;
112
113            let menu_element = element_state.menu.borrow_mut().as_mut().map(|menu| {
114                let mut anchored = anchored().snap_to_window();
115                if let Some(anchor) = this.anchor {
116                    anchored = anchored.anchor(anchor);
117                }
118                anchored = anchored.position(*element_state.position.borrow());
119
120                let mut element = deferred(anchored.child(div().occlude().child(menu.clone())))
121                    .with_priority(1)
122                    .into_any();
123
124                menu_layout_id = Some(element.request_layout(cx));
125                element
126            });
127
128            let mut child_element = this
129                .child_builder
130                .take()
131                .map(|child_builder| (child_builder)(element_state.menu.borrow().is_some()));
132
133            let child_layout_id = child_element
134                .as_mut()
135                .map(|child_element| child_element.request_layout(cx));
136
137            let layout_id = cx.request_layout(
138                &gpui::Style::default(),
139                menu_layout_id.into_iter().chain(child_layout_id),
140            );
141
142            (
143                layout_id,
144                RequestLayoutState {
145                    child_element,
146                    child_layout_id,
147                    menu_element,
148                },
149            )
150        })
151    }
152
153    fn prepaint(
154        &mut self,
155        bounds: Bounds<Pixels>,
156        request_layout: &mut Self::RequestLayoutState,
157        cx: &mut WindowContext,
158    ) -> PrepaintState {
159        cx.with_element_id(Some(self.id.clone()), |cx| {
160            let hitbox = cx.insert_hitbox(bounds, false);
161
162            if let Some(child) = request_layout.child_element.as_mut() {
163                child.prepaint(cx);
164            }
165
166            if let Some(menu) = request_layout.menu_element.as_mut() {
167                menu.prepaint(cx);
168            }
169
170            PrepaintState {
171                hitbox,
172                child_bounds: request_layout
173                    .child_layout_id
174                    .map(|layout_id| cx.layout_bounds(layout_id)),
175            }
176        })
177    }
178
179    fn paint(
180        &mut self,
181        _bounds: Bounds<gpui::Pixels>,
182        request_layout: &mut Self::RequestLayoutState,
183        prepaint_state: &mut Self::PrepaintState,
184        cx: &mut WindowContext,
185    ) {
186        self.with_element_state(cx, |this, element_state, cx| {
187            if let Some(mut child) = request_layout.child_element.take() {
188                child.paint(cx);
189            }
190
191            if let Some(mut menu) = request_layout.menu_element.take() {
192                menu.paint(cx);
193                return;
194            }
195
196            let Some(builder) = this.menu_builder.take() else {
197                return;
198            };
199
200            let attach = this.attach;
201            let menu = element_state.menu.clone();
202            let position = element_state.position.clone();
203            let child_bounds = prepaint_state.child_bounds;
204
205            let hitbox_id = prepaint_state.hitbox.id;
206            cx.on_mouse_event(move |event: &MouseDownEvent, phase, cx| {
207                if phase == DispatchPhase::Bubble
208                    && event.button == MouseButton::Right
209                    && hitbox_id.is_hovered(cx)
210                {
211                    cx.stop_propagation();
212                    cx.prevent_default();
213
214                    let new_menu = (builder)(cx);
215                    let menu2 = menu.clone();
216                    let previous_focus_handle = cx.focused();
217
218                    cx.subscribe(&new_menu, move |modal, _: &DismissEvent, cx| {
219                        if modal.focus_handle(cx).contains_focused(cx) {
220                            if let Some(previous_focus_handle) = previous_focus_handle.as_ref() {
221                                cx.focus(previous_focus_handle);
222                            }
223                        }
224                        *menu2.borrow_mut() = None;
225                        cx.refresh();
226                    })
227                    .detach();
228                    cx.focus_view(&new_menu);
229                    *menu.borrow_mut() = Some(new_menu);
230                    *position.borrow_mut() = if let Some(child_bounds) = child_bounds {
231                        if let Some(attach) = attach {
232                            attach.corner(child_bounds)
233                        } else {
234                            cx.mouse_position()
235                        }
236                    } else {
237                        cx.mouse_position()
238                    };
239                    cx.refresh();
240                }
241            });
242        })
243    }
244}
245
246impl<M: ManagedView> IntoElement for RightClickMenu<M> {
247    type Element = Self;
248
249    fn into_element(self) -> Self::Element {
250        self
251    }
252}