Add active mode

lib/ui/widgets/icon_button_badge.dart

@@ -10,19 +10,24 @@ class IconButtonWithBadge extends StatelessWidget {
   final Widget icon;
   final void Function() onPressed;
   final int number;
+  final bool active;
 
   const IconButtonWithBadge({
     Key key,
     @required this.icon,
     @required this.onPressed,
     this.number = 0,
+    this.active = false,
   })  : assert(icon != null),
         assert(number != null),
+        assert(active != null),
         super(key: key);
 
   @override
   Widget build(BuildContext context) {
-    return Stack(
+    return Container(
+      color: active ? Color(0x55000000) : null,
+      child: Stack(
         alignment: AlignmentDirectional.center,
         children: <Widget>[
           IconButton(icon: icon, onPressed: onPressed),
@@ -45,6 +50,7 @@ class IconButtonWithBadge extends StatelessWidget {
                   ))
               : Container()
         ],
+      ),
     );
   }
 }