1use gpui::{
2 AnyView, DismissEvent, Entity, EventEmitter, FocusHandle, Focusable as _, ManagedView,
3 MouseButton, Subscription,
4};
5use ui::prelude::*;
6
7#[derive(Debug)]
8pub enum DismissDecision {
9 Dismiss(bool),
10 Pending,
11}
12
13pub trait ModalView: ManagedView {
14 fn on_before_dismiss(
15 &mut self,
16 _window: &mut Window,
17 _: &mut Context<Self>,
18 ) -> DismissDecision {
19 DismissDecision::Dismiss(true)
20 }
21
22 fn fade_out_background(&self) -> bool {
23 false
24 }
25}
26
27trait ModalViewHandle {
28 fn on_before_dismiss(&mut self, window: &mut Window, cx: &mut App) -> DismissDecision;
29 fn view(&self) -> AnyView;
30 fn fade_out_background(&self, cx: &mut App) -> bool;
31}
32
33impl<V: ModalView> ModalViewHandle for Entity<V> {
34 fn on_before_dismiss(&mut self, window: &mut Window, cx: &mut App) -> DismissDecision {
35 self.update(cx, |this, cx| this.on_before_dismiss(window, cx))
36 }
37
38 fn view(&self) -> AnyView {
39 self.clone().into()
40 }
41
42 fn fade_out_background(&self, cx: &mut App) -> bool {
43 self.read(cx).fade_out_background()
44 }
45}
46
47pub struct ActiveModal {
48 modal: Box<dyn ModalViewHandle>,
49 _subscriptions: [Subscription; 2],
50 previous_focus_handle: Option<FocusHandle>,
51 focus_handle: FocusHandle,
52}
53
54pub struct ModalLayer {
55 active_modal: Option<ActiveModal>,
56 dismiss_on_focus_lost: bool,
57}
58
59pub(crate) struct ModalOpenedEvent;
60
61impl EventEmitter<ModalOpenedEvent> for ModalLayer {}
62
63impl Default for ModalLayer {
64 fn default() -> Self {
65 Self::new()
66 }
67}
68
69impl ModalLayer {
70 pub fn new() -> Self {
71 Self {
72 active_modal: None,
73 dismiss_on_focus_lost: false,
74 }
75 }
76
77 pub fn toggle_modal<V, B>(&mut self, window: &mut Window, cx: &mut Context<Self>, build_view: B)
78 where
79 V: ModalView,
80 B: FnOnce(&mut Window, &mut Context<V>) -> V,
81 {
82 if let Some(active_modal) = &self.active_modal {
83 let is_close = active_modal.modal.view().downcast::<V>().is_ok();
84 let did_close = self.hide_modal(window, cx);
85 if is_close || !did_close {
86 return;
87 }
88 }
89 let new_modal = cx.new(|cx| build_view(window, cx));
90 self.show_modal(new_modal, window, cx);
91 cx.emit(ModalOpenedEvent);
92 }
93
94 fn show_modal<V>(&mut self, new_modal: Entity<V>, window: &mut Window, cx: &mut Context<Self>)
95 where
96 V: ModalView,
97 {
98 let focus_handle = cx.focus_handle();
99 self.active_modal = Some(ActiveModal {
100 modal: Box::new(new_modal.clone()),
101 _subscriptions: [
102 cx.subscribe_in(
103 &new_modal,
104 window,
105 |this, _, _: &DismissEvent, window, cx| {
106 this.hide_modal(window, cx);
107 },
108 ),
109 cx.on_focus_out(&focus_handle, window, |this, _event, window, cx| {
110 if this.dismiss_on_focus_lost {
111 this.hide_modal(window, cx);
112 }
113 }),
114 ],
115 previous_focus_handle: window.focused(cx),
116 focus_handle,
117 });
118 cx.defer_in(window, move |_, window, cx| {
119 window.focus(&new_modal.focus_handle(cx));
120 });
121 cx.notify();
122 }
123
124 pub fn hide_modal(&mut self, window: &mut Window, cx: &mut Context<Self>) -> bool {
125 let Some(active_modal) = self.active_modal.as_mut() else {
126 self.dismiss_on_focus_lost = false;
127 return false;
128 };
129
130 match active_modal.modal.on_before_dismiss(window, cx) {
131 DismissDecision::Dismiss(dismiss) => {
132 self.dismiss_on_focus_lost = !dismiss;
133 if !dismiss {
134 return false;
135 }
136 }
137 DismissDecision::Pending => {
138 self.dismiss_on_focus_lost = false;
139 return false;
140 }
141 }
142
143 if let Some(active_modal) = self.active_modal.take() {
144 if let Some(previous_focus) = active_modal.previous_focus_handle
145 && active_modal.focus_handle.contains_focused(window, cx)
146 {
147 previous_focus.focus(window);
148 }
149 cx.notify();
150 }
151 true
152 }
153
154 pub fn active_modal<V>(&self) -> Option<Entity<V>>
155 where
156 V: 'static,
157 {
158 let active_modal = self.active_modal.as_ref()?;
159 active_modal.modal.view().downcast::<V>().ok()
160 }
161
162 pub fn has_active_modal(&self) -> bool {
163 self.active_modal.is_some()
164 }
165}
166
167impl Render for ModalLayer {
168 fn render(&mut self, _: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
169 let Some(active_modal) = &self.active_modal else {
170 return div();
171 };
172
173 div()
174 .occlude()
175 .absolute()
176 .size_full()
177 .top_0()
178 .left_0()
179 .when(active_modal.modal.fade_out_background(cx), |el| {
180 let mut background = cx.theme().colors().elevated_surface_background;
181 background.fade_out(0.2);
182 el.bg(background)
183 })
184 .on_mouse_down(
185 MouseButton::Left,
186 cx.listener(|this, _, window, cx| {
187 this.hide_modal(window, cx);
188 }),
189 )
190 .child(
191 v_flex()
192 .h(px(0.0))
193 .top_20()
194 .flex()
195 .flex_col()
196 .items_center()
197 .track_focus(&active_modal.focus_handle)
198 .child(
199 h_flex()
200 .occlude()
201 .child(active_modal.modal.view())
202 .on_mouse_down(MouseButton::Left, |_, _, cx| {
203 cx.stop_propagation();
204 }),
205 ),
206 )
207 }
208}