[Flutter]Listview in NestedScrollView

sliver_header.dart

import 'package:flutter/material.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.purple,
      ),
      home: MyHomePage(title: 'Sliver App'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> with TickerProviderStateMixin {
  TabController _tabController;
  ScrollController _scrollController;

  int _selectedIndex = 0;

  @override
  void initState() {
    _tabController = TabController(vsync: this, length: 2);
    _scrollController = ScrollController();
    _scrollController.addListener(_didScroll);
    super.initState();
  }

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

  void _onItemTapped(int index) {
    setState(() {
      _selectedIndex = index;
      _tabController.index = index;
    });
  }

  void _didScroll() {
    print("didScroll");
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: DefaultTabController(
        length: _tabController.length,
        child: NestedScrollView(
          controller: _scrollController,
          key: PageStorageKey(widget.title),
          headerSliverBuilder: (context, innerBoxScrolled) => [
            SliverAppBar(
              title: Text(widget.title),
              floating: true,
              pinned: true,
              snap: true,
              bottom: const PreferredSize(
                  child: SizedBox(), preferredSize: Size.fromHeight(0.0)),
            ),
          ],
          body: TabBarView(
              physics: NeverScrollableScrollPhysics(),
              controller: _tabController,
              children: <Widget>[
                LeftTab(),
                RightTab(),
              ]),
        ),
      ),
      bottomNavigationBar: BottomNavigationBar(
        items: const <BottomNavigationBarItem>[
          BottomNavigationBarItem(
            icon: Icon(Icons.star),
            title: Text('Left'),
          ),
          BottomNavigationBarItem(
            icon: Icon(Icons.star_border),
            title: Text('Right'),
          ),
        ],
        currentIndex: _selectedIndex,
        selectedItemColor: Colors.amber[800],
        onTap: _onItemTapped,
      ),
    );
  }
}

class LeftTab extends StatefulWidget {
  LeftTab({Key key}) : super(key: key);

  @override
  _LeftTabState createState() => _LeftTabState();
}

class _LeftTabState extends State<LeftTab> {
  @override
  Widget build(BuildContext context) {
    return ListView.builder(
        key: PageStorageKey("Left"),
        itemCount: 200,
        itemBuilder: (BuildContext context, int index) {
          return Align(
              alignment: Alignment.center, child: Text("Left: $index"));
        });
  }
}

class RightTab extends StatefulWidget {
  @override
  _RightTabState createState() => _RightTabState();
}

class _RightTabState extends State<RightTab> {
  @override
  Widget build(BuildContext context) {
    return ListView.builder(
        key: PageStorageKey("Right"),
        itemCount: 200,
        itemBuilder: (BuildContext context, int index) {
          return Align(
              alignment: Alignment.center, child: Text("Right: $index"));
        });
  }
}