Future<bool> _selectWinner(
    BuildContext context, List<User> playerList) async {
  return showDialog(
        context: context,
        builder: (context) {
          return StatefulBuilder(builder: (context, setState) {
            List<Widget> playerSelect = [];
            playerList.forEach((User player) {
              Widget listTile = Row(
                children: <Widget>[
                  Radio(
                    value: player.deviceId,
                    groupValue: winnerId,
                    onChanged: (String id) {
                      winnerId = id;
                      setState(() {});
                    },
                  ),
                  Text(player.name)
                ],
              );
              playerSelect.add(listTile);
            });
            return AlertDialog(
              title: new Text('Select Winner !'),
              content: Column(
                mainAxisSize: MainAxisSize.min,
                children: playerSelect,
              ),
              actions: <Widget>[
                new FlatButton(
                  onPressed: () => Navigator.of(context).pop(false),
                  child: new Text('No'),
                ),
                new FlatButton(
                  onPressed: () => Navigator.of(context).pop(true),
                  child: new Text('Yes'),
                ),
              ],
            );
          });
        },
      ) ??
      false;
}