1use gpui::{
2 AnyView, DismissEvent, Entity, FocusHandle, Focusable as _, ManagedView, MouseButton,
3 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
59impl Default for ModalLayer {
60 fn default() -> Self {
61 Self::new()
62 }
63}
64
65impl ModalLayer {
66 pub fn new() -> Self {
67 Self {
68 active_modal: None,
69 dismiss_on_focus_lost: false,
70 }
71 }
72
73 pub fn toggle_modal<V, B>(&mut self, window: &mut Window, cx: &mut Context<Self>, build_view: B)
74 where
75 V: ModalView,
76 B: FnOnce(&mut Window, &mut Context<V>) -> V,
77 {
78 if let Some(active_modal) = &self.active_modal {
79 let is_close = active_modal.modal.view().downcast::<V>().is_ok();
80 let did_close = self.hide_modal(window, cx);
81 if is_close || !did_close {
82 return;
83 }
84 }
85 let new_modal = cx.new(|cx| build_view(window, cx));
86 self.show_modal(new_modal, window, cx);
87 }
88
89 fn show_modal<V>(&mut self, new_modal: Entity<V>, window: &mut Window, cx: &mut Context<Self>)
90 where
91 V: ModalView,
92 {
93 let focus_handle = cx.focus_handle();
94 self.active_modal = Some(ActiveModal {
95 modal: Box::new(new_modal.clone()),
96 _subscriptions: [
97 cx.subscribe_in(
98 &new_modal,
99 window,
100 |this, _, _: &DismissEvent, window, cx| {
101 this.hide_modal(window, cx);
102 },
103 ),
104 cx.on_focus_out(&focus_handle, window, |this, _event, window, cx| {
105 if this.dismiss_on_focus_lost {
106 this.hide_modal(window, cx);
107 }
108 }),
109 ],
110 previous_focus_handle: window.focused(cx),
111 focus_handle,
112 });
113 cx.defer_in(window, move |_, window, cx| {
114 window.focus(&new_modal.focus_handle(cx));
115 });
116 cx.notify();
117 }
118
119 pub fn hide_modal(&mut self, window: &mut Window, cx: &mut Context<Self>) -> bool {
120 let Some(active_modal) = self.active_modal.as_mut() else {
121 self.dismiss_on_focus_lost = false;
122 return false;
123 };
124
125 match active_modal.modal.on_before_dismiss(window, cx) {
126 DismissDecision::Dismiss(dismiss) => {
127 self.dismiss_on_focus_lost = !dismiss;
128 if !dismiss {
129 return false;
130 }
131 }
132 DismissDecision::Pending => {
133 self.dismiss_on_focus_lost = false;
134 return false;
135 }
136 }
137
138 if let Some(active_modal) = self.active_modal.take() {
139 if let Some(previous_focus) = active_modal.previous_focus_handle {
140 if active_modal.focus_handle.contains_focused(window, cx) {
141 previous_focus.focus(window);
142 }
143 }
144 cx.notify();
145 }
146 true
147 }
148
149 pub fn active_modal<V>(&self) -> Option<Entity<V>>
150 where
151 V: 'static,
152 {
153 let active_modal = self.active_modal.as_ref()?;
154 active_modal.modal.view().downcast::<V>().ok()
155 }
156
157 pub fn has_active_modal(&self) -> bool {
158 self.active_modal.is_some()
159 }
160}
161
162impl Render for ModalLayer {
163 fn render(&mut self, _: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
164 let Some(active_modal) = &self.active_modal else {
165 return div();
166 };
167
168 div()
169 .occlude()
170 .absolute()
171 .size_full()
172 .top_0()
173 .left_0()
174 .when(active_modal.modal.fade_out_background(cx), |el| {
175 let mut background = cx.theme().colors().elevated_surface_background;
176 background.fade_out(0.2);
177 el.bg(background)
178 })
179 .on_mouse_down(
180 MouseButton::Left,
181 cx.listener(|this, _, window, cx| {
182 this.hide_modal(window, cx);
183 }),
184 )
185 .child(
186 v_flex()
187 .h(px(0.0))
188 .top_20()
189 .flex()
190 .flex_col()
191 .items_center()
192 .track_focus(&active_modal.focus_handle)
193 .child(
194 h_flex()
195 .occlude()
196 .child(active_modal.modal.view())
197 .on_mouse_down(MouseButton::Left, |_, _, cx| {
198 cx.stop_propagation();
199 }),
200 ),
201 )
202 }
203}