在flutter中使用tabbar时如何滚动单个页面？

import 'package:flutter/material.dart';

class MyTabBarPage extends StatefulWidget {
  @override
  _MyTabBarPageState createState() => _MyTabBarPageState();
}

class _MyTabBarPageState extends State<MyTabBarPage> with SingleTickerProviderStateMixin {
  TabController _tabController;

  @override
  void initState() {
    super.initState();
    _tabController = TabController(length: 3, vsync: this);
  }

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('TabBar Demo'),
        bottom: TabBar(
          controller: _tabController,
          tabs: [
            Tab(text: 'Tab 1'),
            Tab(text: 'Tab 2'),
            Tab(text: 'Tab 3'),
          ],
        ),
      ),
      body: TabBarView(
        controller: _tabController,
        children: [
          NestedScrollView(
            headerSliverBuilder: (BuildContext context, bool innerBoxIsScrolled) {
              return [
                SliverAppBar(
                  title: Text('Tab 1'),
                  pinned: true,
                  floating: true,
                  snap: true,
                ),
              ];
            },
            body: ListView.builder(
              itemCount: 100,
              itemBuilder: (BuildContext context, int index) {
                return ListTile(
                  title: Text('Item $index'),
                );
              },
            ),
          ),
          Container(
            child: Center(
              child: Text('Tab 2'),
            ),
          ),
          Container(
            child: Center(
              child: Text('Tab 3'),
            ),
          ),
        ],
      ),
    );
  }
}