popover_menu.rs

  1use std::{cell::RefCell, rc::Rc};
  2
  3use gpui::{
  4    overlay, point, prelude::FluentBuilder, px, rems, AnchorCorner, AnyElement, Bounds,
  5    DismissEvent, DispatchPhase, Element, ElementContext, ElementId, InteractiveBounds,
  6    IntoElement, LayoutId, ManagedView, MouseDownEvent, ParentElement, Pixels, Point, View,
  7    VisualContext, WindowContext,
  8};
  9
 10use crate::{Clickable, Selectable};
 11
 12pub trait PopoverTrigger: IntoElement + Clickable + Selectable + 'static {}
 13
 14impl<T: IntoElement + Clickable + Selectable + 'static> PopoverTrigger for T {}
 15
 16pub struct PopoverMenu<M: ManagedView> {
 17    id: ElementId,
 18    child_builder: Option<
 19        Box<
 20            dyn FnOnce(
 21                    Rc<RefCell<Option<View<M>>>>,
 22                    Option<Rc<dyn Fn(&mut WindowContext) -> Option<View<M>> + 'static>>,
 23                ) -> AnyElement
 24                + 'static,
 25        >,
 26    >,
 27    menu_builder: Option<Rc<dyn Fn(&mut WindowContext) -> Option<View<M>> + 'static>>,
 28    anchor: AnchorCorner,
 29    attach: Option<AnchorCorner>,
 30    offset: Option<Point<Pixels>>,
 31}
 32
 33impl<M: ManagedView> PopoverMenu<M> {
 34    pub fn menu(mut self, f: impl Fn(&mut WindowContext) -> Option<View<M>> + 'static) -> Self {
 35        self.menu_builder = Some(Rc::new(f));
 36        self
 37    }
 38
 39    pub fn trigger<T: PopoverTrigger>(mut self, t: T) -> Self {
 40        self.child_builder = Some(Box::new(|menu, builder| {
 41            let open = menu.borrow().is_some();
 42            t.selected(open)
 43                .when_some(builder, |el, builder| {
 44                    el.on_click({
 45                        move |_, cx| {
 46                            let Some(new_menu) = (builder)(cx) else {
 47                                return;
 48                            };
 49                            let menu2 = menu.clone();
 50                            let previous_focus_handle = cx.focused();
 51
 52                            cx.subscribe(&new_menu, move |modal, _: &DismissEvent, cx| {
 53                                if modal.focus_handle(cx).contains_focused(cx) {
 54                                    if let Some(previous_focus_handle) =
 55                                        previous_focus_handle.as_ref()
 56                                    {
 57                                        cx.focus(previous_focus_handle);
 58                                    }
 59                                }
 60                                *menu2.borrow_mut() = None;
 61                                cx.refresh();
 62                            })
 63                            .detach();
 64                            cx.focus_view(&new_menu);
 65                            *menu.borrow_mut() = Some(new_menu);
 66                        }
 67                    })
 68                })
 69                .into_any_element()
 70        }));
 71        self
 72    }
 73
 74    /// anchor defines which corner of the menu to anchor to the attachment point
 75    /// (by default the cursor position, but see attach)
 76    pub fn anchor(mut self, anchor: AnchorCorner) -> Self {
 77        self.anchor = anchor;
 78        self
 79    }
 80
 81    /// attach defines which corner of the handle to attach the menu's anchor to
 82    pub fn attach(mut self, attach: AnchorCorner) -> Self {
 83        self.attach = Some(attach);
 84        self
 85    }
 86
 87    /// offset offsets the position of the content by that many pixels.
 88    pub fn offset(mut self, offset: Point<Pixels>) -> Self {
 89        self.offset = Some(offset);
 90        self
 91    }
 92
 93    fn resolved_attach(&self) -> AnchorCorner {
 94        self.attach.unwrap_or_else(|| match self.anchor {
 95            AnchorCorner::TopLeft => AnchorCorner::BottomLeft,
 96            AnchorCorner::TopRight => AnchorCorner::BottomRight,
 97            AnchorCorner::BottomLeft => AnchorCorner::TopLeft,
 98            AnchorCorner::BottomRight => AnchorCorner::TopRight,
 99        })
100    }
101
102    fn resolved_offset(&self, cx: &WindowContext) -> Point<Pixels> {
103        self.offset.unwrap_or_else(|| {
104            // Default offset = 4px padding + 1px border
105            let offset = rems(5. / 16.) * cx.rem_size();
106            match self.anchor {
107                AnchorCorner::TopRight | AnchorCorner::BottomRight => point(offset, px(0.)),
108                AnchorCorner::TopLeft | AnchorCorner::BottomLeft => point(-offset, px(0.)),
109            }
110        })
111    }
112}
113
114/// Creates a [`PopoverMenu`]
115pub fn popover_menu<M: ManagedView>(id: impl Into<ElementId>) -> PopoverMenu<M> {
116    PopoverMenu {
117        id: id.into(),
118        child_builder: None,
119        menu_builder: None,
120        anchor: AnchorCorner::TopLeft,
121        attach: None,
122        offset: None,
123    }
124}
125
126pub struct PopoverMenuState<M> {
127    child_layout_id: Option<LayoutId>,
128    child_element: Option<AnyElement>,
129    child_bounds: Option<Bounds<Pixels>>,
130    menu_element: Option<AnyElement>,
131    menu: Rc<RefCell<Option<View<M>>>>,
132}
133
134impl<M: ManagedView> Element for PopoverMenu<M> {
135    type State = PopoverMenuState<M>;
136
137    fn request_layout(
138        &mut self,
139        element_state: Option<Self::State>,
140        cx: &mut ElementContext,
141    ) -> (gpui::LayoutId, Self::State) {
142        let mut menu_layout_id = None;
143
144        let (menu, child_bounds) = if let Some(element_state) = element_state {
145            (element_state.menu, element_state.child_bounds)
146        } else {
147            (Rc::default(), None)
148        };
149
150        let menu_element = menu.borrow_mut().as_mut().map(|menu| {
151            let mut overlay = overlay().snap_to_window().anchor(self.anchor);
152
153            if let Some(child_bounds) = child_bounds {
154                overlay = overlay.position(
155                    self.resolved_attach().corner(child_bounds) + self.resolved_offset(cx),
156                );
157            }
158
159            let mut element = overlay.child(menu.clone()).into_any();
160            menu_layout_id = Some(element.request_layout(cx));
161            element
162        });
163
164        let mut child_element = self
165            .child_builder
166            .take()
167            .map(|child_builder| (child_builder)(menu.clone(), self.menu_builder.clone()));
168
169        let child_layout_id = child_element
170            .as_mut()
171            .map(|child_element| child_element.request_layout(cx));
172
173        let layout_id = cx.request_layout(
174            &gpui::Style::default(),
175            menu_layout_id.into_iter().chain(child_layout_id),
176        );
177
178        (
179            layout_id,
180            PopoverMenuState {
181                menu,
182                child_element,
183                child_layout_id,
184                menu_element,
185                child_bounds,
186            },
187        )
188    }
189
190    fn paint(
191        &mut self,
192        _: Bounds<gpui::Pixels>,
193        element_state: &mut Self::State,
194        cx: &mut ElementContext,
195    ) {
196        if let Some(mut child) = element_state.child_element.take() {
197            child.paint(cx);
198        }
199
200        if let Some(child_layout_id) = element_state.child_layout_id.take() {
201            element_state.child_bounds = Some(cx.layout_bounds(child_layout_id));
202        }
203
204        if let Some(mut menu) = element_state.menu_element.take() {
205            menu.paint(cx);
206
207            if let Some(child_bounds) = element_state.child_bounds {
208                let interactive_bounds = InteractiveBounds {
209                    bounds: child_bounds,
210                    stacking_order: cx.stacking_order().clone(),
211                };
212
213                // Mouse-downing outside the menu dismisses it, so we don't
214                // want a click on the toggle to re-open it.
215                cx.on_mouse_event(move |e: &MouseDownEvent, phase, cx| {
216                    if phase == DispatchPhase::Bubble
217                        && interactive_bounds.visibly_contains(&e.position, cx)
218                    {
219                        cx.stop_propagation()
220                    }
221                })
222            }
223        }
224    }
225}
226
227impl<M: ManagedView> IntoElement for PopoverMenu<M> {
228    type Element = Self;
229
230    fn element_id(&self) -> Option<gpui::ElementId> {
231        Some(self.id.clone())
232    }
233
234    fn into_element(self) -> Self::Element {
235        self
236    }
237}