NewstedScrollview

void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context)=> MaterialApp(
      title: 'Nested Views',
      theme: ThemeData(
          brightness: Brightness.light,
          primaryColor: Color(0xFF44318e),
          accentColor: Color(0xFFe98074),
          fontFamily: 'Quicksand',
          textTheme: TextTheme(
              headline: TextStyle(
                  fontSize: 55.0, fontWeight: FontWeight.bold, fontFamily: "Quicksand",
                  color: Color(0xFFe98074)),
              title: TextStyle(
                  fontSize: 20.0, fontWeight: FontWeight.bold, fontFamily: "Quicksand"))),
      home: Home()
  );
}
class Home extends StatefulWidget {
  Home({Key key}) : super(key: key);
  @override
  _HomeState createState() => _HomeState();
}
class _HomeState extends State<Home> with TickerProviderStateMixin {
  _HomeState({Key key});

  @override
  void initState() {
    super.initState();
  }

  @override
  void dispose() {
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    Widget _nestedView(){
      return NestedScrollView(
        headerSliverBuilder:
            (BuildContext context, bool innerBoxIsScrolled) {
          return <Widget>[
            SliverAppBar(
                backgroundColor: Colors.white,
                expandedHeight: 400.0,
                title: Text(
                  "Nested Scrollview",
                ),
                floating: false,
                pinned: true,
                flexibleSpace: FlexibleSpaceBar(
                  collapseMode: CollapseMode.parallax,
                  centerTitle: true,
                  background: Container(
                    color: Colors.blue,
                  )
                ),
                bottom: PreferredSize(
                    child: Padding(
                      padding: const EdgeInsets.all(2.0),
                      child: Container(
                        width: MediaQuery.of(context).size.width,
                        child: Text("My take"),
                        decoration: new BoxDecoration(
                            borderRadius: BorderRadius.all(Radius.circular(4.0)),
                            color: Colors.white70,
                            border: new Border.all(color: Colors.grey[200],
                            )
                        ),
                      ),
                    ),
                    preferredSize: Size(double.infinity, 40.0))),
          ];
        },
        body: Container(
          height: MediaQuery.of(context).size.height*2,
          decoration: BoxDecoration(
            color: Colors.grey[50],
            borderRadius: BorderRadius.all(Radius.circular(0.0) //
            ),
          ),
          child: ListView(
            children: <Widget>[
              ListTile(
                title: Text("Testing Scrollview"),
                onTap: () {},
              ),
              Container(
                height: 410.0,
                child: Text("Testing Scrollview"),
              ),
              SizedBox(height: 240.0),
              Container(
                height: 210.0,
                child: Text("Testing Scrollview"),
              ),
            ],
          ),
        ),
      );
    }
    return Scaffold(
      appBar: AppBar(title: Text("Nested Views"),),
      body: _nestedView()
    );
  }
}