Hide title in Flutter SliverAppBar on scroll

SABT.dart

class SABT extends StatefulWidget {
  final Widget child;
  const SABT({
    Key key,
    @required this.child,
  }) : super(key: key);
  @override
  _SABTState createState() {
    return new _SABTState();
  }
}
class _SABTState extends State<SABT> {
  ScrollPosition _position;
  bool _visible;
  @override
  void dispose() {
    _removeListener();
    super.dispose();
  }
  @override
  void didChangeDependencies() {
    super.didChangeDependencies();
    _removeListener();
    _addListener();
  }
  void _addListener() {
    _position = Scrollable.of(context)?.position;
    _position?.addListener(_positionListener);
    _positionListener();
  }
  void _removeListener() {
    _position?.removeListener(_positionListener);
  }
  void _positionListener() {
    final FlexibleSpaceBarSettings settings =
      context.dependOnInheritedWidgetOfExactType();
    print(settings.minExtent);
    bool visible = settings == null || settings.currentExtent > settings.minExtent+10;
    if (_visible != visible) {
      setState(() {
        _visible = visible;
      });
    }
  }
  @override
  Widget build(BuildContext context) {
    return AnimatedOpacity(
      duration: Duration(milliseconds: 300),
      opacity: _visible?1:0,
      child: widget.child,
    );
  }
}

sliverAppbar

SliverAppBar(
              pinned: true,
              expandedHeight: 300,
              excludeHeaderSemantics: true,
              flexibleSpace: FlexibleSpaceBar(
                collapseMode: CollapseMode.pin,
                background: Container(
                  decoration: BoxDecoration(
                      image: DecorationImage(
                          image: AssetImage("assets/images/cardimage.png"),
                          fit: BoxFit.fitHeight)),
                centerTitle: true,
                titlePadding: EdgeInsets.symmetric(horizontal: 20),
                title: SABT(child: Text(
                  'Watch: Gameplay for the first 13 games optimised for Xbox Series X',
                  style: TextStyle(
                    fontFamily: 'League',
                    fontSize: 19,
                    color: Colors.white,
                  ),
                ),),
              ),
            ),