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