use adw box for more things

src/ui/play_queue.blp

@@ -2,10 +2,10 @@ using Gtk 4.0;
 using Adw 1;
 using Gio 2.0;
 
-template $UiPlayQueue: Box {
+template $UiPlayQueue: Adw.Bin {
   name: "play-queue";
 
-  Stack {
+  child: Stack {
     visible-child-name: bind $visible_child_name (template.playbin as <$Playbin>.play_queue as <Gio.ListStore>.n-items) as <string>;
 
     StackPage {
@@ -43,5 +43,5 @@ template $UiPlayQueue: Box {
         }
       };
     }
-  }
+  };
 }

src/ui/play_queue.vala

@@ -112,7 +112,7 @@ class Ui.PlayQueueSong : Gtk.Box {
 }
 
 [GtkTemplate (ui = "/eu/callcc/audrey/ui/play_queue.ui")]
-public class Ui.PlayQueue : Gtk.Box {
+public class Ui.PlayQueue : Adw.Bin {
     private weak Playbin _playbin;
     public Playbin playbin {
         get { return _playbin; }

src/ui/playbar.blp

@@ -1,13 +1,13 @@
 using Gtk 4.0;
+using Adw 1;
 
-template $UiPlaybar: Box {
+template $UiPlaybar: Adw.Bin {
+  child: CenterBox {
+    hexpand: true;
     styles [
       "toolbar",
     ]
 
-  CenterBox {
-    hexpand: true;
-
     [start]
     Box {
       AspectFrame {
@@ -168,5 +168,5 @@ template $UiPlaybar: Box {
         };
       }
     }
-  }
+  };
 }

src/ui/playbar.vala

@@ -1,5 +1,5 @@
 [GtkTemplate (ui = "/eu/callcc/audrey/ui/playbar.ui")]
-class Ui.Playbar : Gtk.Box {
+class Ui.Playbar : Adw.Bin {
     public Subsonic.Song? song { get; set; }
     public Gdk.Paintable? playing_cover_art { get; set; }
     public weak Playbin playbin { get; set; }