I. use NotificationListener to monitor rolling progress

                                 In addition to ScrollNotification, there are SizeChangedLayoutNotification, KeepAliveNotification, LayoutChangedNotification, etc. in the Flutter.

NotificationListener(
      onNotification: (notification){
        print(notification.metrics.pixels); // Current scroll position
        print(notification.metrics.maxScrollExtent); // Maximum range of rolling work
        switch (notification.runtimeType){
          case ScrollStartNotification: print("Start rolling"); break;
          case ScrollUpdateNotification: print("Rolling"); break;
          case ScrollEndNotification: print("Rolling stop"); break;
          case OverscrollNotification: print("Scroll to boundary"); break;
        }
        return true;
      },
      child: ListView.builder(
          itemCount: 50,
          itemBuilder: (context, index) {
            return ListTile(title: Text("$index"),);
          }
      ),
    )

II. Use custom notice

• First create a notification:

class MyNotification extends Notification {
  final String msg;

  MyNotification(this.msg);
}

• Next, we can use our customized Notifications:

class NotificationRoute extends StatefulWidget {
  @override
  _NotificationRouteState createState() {
    // TODO: implement createState
    return _NotificationRouteState();
  }
}

class _NotificationRouteState extends State<NotificationRoute> {
  String text = '';

  @override
  Widget build(BuildContext context) {
    // TODO: implement build
    return NotificationListener(
      onNotification: (MyNotification notification) {
        setState(() {
          text = notification.msg;
        });
        return false;
      },
      child: Center(
        child: Column(
          children: <Widget>[
            Text('msg: $text'),
            Builder(
              builder: (context) => RaisedButton(
                onPressed: () => MyNotification('Notice received').dispatch(context),
                child: Text('Sending notice'),
              ),
            )
          ],
        ),
      ),
    );
  }
}