import 'package:flutter/foundation.dart'; class CastContext { static final _instance = new CastContext._internal(); CastContext._internal(); static CastContext get instance => _instance; final ValueNotifier state = ValueNotifier(CastState.unavailable); } enum CastState { default_state, // 0 unavailable, // 1 unconnected, // 2 connecting, // 3 connected, // 4 }