feat: Basic Application Settings (#58)

* .

* .

* .

* update modal

crates/ui/src/root.rs

@@ -128,7 +128,7 @@ impl ContextModal for Window {
 type Builder = Rc<dyn Fn(Modal, &mut Window, &mut App) -> Modal + 'static>;
 
 #[derive(Clone)]
-pub struct ActiveModal {
+pub(crate) struct ActiveModal {
     focus_handle: FocusHandle,
     builder: Builder,
 }
@@ -137,7 +137,7 @@ pub struct ActiveModal {
 ///
 /// It is used to manage the Modal, and Notification.
 pub struct Root {
-    pub active_modals: Vec<ActiveModal>,
+    pub(crate) active_modals: Vec<ActiveModal>,
     pub notification: Entity<NotificationList>,
     pub focused_input: Option<Entity<InputState>>,
     /// Used to store the focus handle of the previous view.
@@ -194,36 +194,46 @@ impl Root {
     /// Render the Modal layer.
     pub fn render_modal_layer(window: &mut Window, cx: &mut App) -> Option<impl IntoElement> {
         let root = window.root::<Root>()??;
+
         let active_modals = root.read(cx).active_modals.clone();
-        let mut has_overlay = false;
 
         if active_modals.is_empty() {
             return None;
         }
 
-        Some(
-            div().children(active_modals.iter().enumerate().map(|(i, active_modal)| {
+        let mut show_overlay_ix = None;
+
+        let mut modals = active_modals
+            .iter()
+            .enumerate()
+            .map(|(i, active_modal)| {
                 let mut modal = Modal::new(window, cx);
 
                 modal = (active_modal.builder)(modal, window, cx);
-                modal.layer_ix = i;
+
                 // Give the modal the focus handle, because `modal` is a temporary value, is not possible to
                 // keep the focus handle in the modal.
                 //
                 // So we keep the focus handle in the `active_modal`, this is owned by the `Root`.
                 modal.focus_handle = active_modal.focus_handle.clone();
 
-                // Keep only have one overlay, we only render the first modal with overlay.
-                if has_overlay {
-                    modal.overlay = false;
-                }
+                modal.layer_ix = i;
+                // Find the modal which one needs to show overlay.
                 if modal.has_overlay() {
-                    has_overlay = true;
+                    show_overlay_ix = Some(i);
                 }
 
                 modal
-            })),
-        )
+            })
+            .collect::<Vec<_>>();
+
+        if let Some(ix) = show_overlay_ix {
+            if let Some(modal) = modals.get_mut(ix) {
+                modal.overlay_visible = true;
+            }
+        }
+
+        Some(div().children(modals))
     }
 
     /// Return the root view of the Root.