Flutter 解决NestedScrollView与TabBar双列表滚动位置同步问题

import 'package:flutter/material.dart';

class NestedScrollViewWithTabBarExample extends StatefulWidget {
  @override
  _NestedScrollViewWithTabBarExampleState createState() => _NestedScrollViewWithTabBarExampleState();
}

class _NestedScrollViewWithTabBarExampleState extends State<NestedScrollViewWithTabBarExample> with SingleTickerProviderStateMixin {
  TabController _tabController;

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

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: NestedScrollView(
        headerSliverBuilder: (BuildContext context, bool innerBoxIsScrolled) {
          return <Widget>[
            SliverAppBar(
              title: Text('AppBar Title'),
              pinned: true,
              expandedHeight: 200.0,
              bottom: TabBar(
                controller: _tabController,
                tabs: <Widget>[
                  Tab(text: 'Tab 1'),
                  Tab(text: 'Tab 2'),
                ],
              ),
            ),
          ];
        },
        body: TabBarView(
          controller: _tabController,
          children: <Widget>[
            ListView.builder(
              itemCount: 100,
              itemBuilder: (BuildContext context, int index) {
                return ListTile(title: Text('Item $index'));
              },
            ),
            ListView.builder(
              itemCount: 100,
              itemBuilder: (BuildContext context, int index) {
                return List