the internal elastic scroll is not clean by extended_nested_scroll_view

While dragging the page to the top, quickly pull up, the page will shake. I guess the internal elastic scroll is not clean by extended_nested_scroll_view. The simulator is good, only the real machine has problems.
import 'dart:io';
import 'package:flutter/material.dart' hide NestedScrollView;
import 'package:extended_nested_scroll_view/extended_nested_scroll_view.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primaryColor: Colors.white,
      ),
      home: NewsScreen(),
      debugShowCheckedModeBanner: false,
    );
  }
}

class NewsScreen extends StatefulWidget {
  @override
  State<StatefulWidget> createState() => _NewsScreenState();
}

class _NewsScreenState extends State<NewsScreen> with TickerProviderStateMixin {
  final List<String> _tabs = <String>[
    "Featured",
    "Popular",
    "Latest",
  ];
  TabController _tabController;

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

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

  @override
  Widget build(BuildContext context) {
    return Material(
      child: Scaffold(
        body: NestedScrollView(
          headerSliverBuilder: (BuildContext context, bool innerBoxIsScrolled) {
            return <Widget>[
              SliverOverlapAbsorber(
                handle:
                    NestedScrollView.sliverOverlapAbsorberHandleFor(context),
                sliver: SliverSafeArea(
                  top: false,
                  bottom: Platform.isIOS ? false : true,
                  sliver: SliverAppBar(
                    title: Text('Tab Demo'),
                    floating: true,
                    pinned: true,
                    snap: true,
                    forceElevated: innerBoxIsScrolled,
                    bottom: TabBar(
                      controller: _tabController,
                      tabs:
                          _tabs.map((String name) => Tab(text: name)).toList(),
                    ),
                  ),
                ),
              ),
            ];
          },
          innerScrollPositionKeyBuilder: () {
            return Key('Tab${_tabController.index}');
          },
          body: TabBarView(
            controller: _tabController,
            children: _tabs.asMap().entries.map((entry) {
              return TabViewItem(
                tabKey: Key('Tab${entry.key}'),
                tabName: entry.value,
              );
            }).toList(),
          ),
        ),
      ),
    );
  }
}

class TabViewItem extends StatefulWidget {
  final Key tabKey;
  final String tabName;

  const TabViewItem({Key key, this.tabKey, this.tabName}) : super(key: key);

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

class _TabViewItemState extends State<TabViewItem>
    with AutomaticKeepAliveClientMixin {
  @override
  Widget build(BuildContext context) {
    super.build(context);
    return SafeArea(
      top: false,
      bottom: false,
      child: Builder(
        builder: (BuildContext context) {
          return NotificationListener<ScrollNotification>(
            onNotification: (scrollNotification) {
              return true;
            },
            child: NestedScrollViewInnerScrollPositionKeyWidget(
              widget.tabKey,
              CustomScrollView(
                slivers: <Widget>[
                  SliverOverlapInjector(
                    handle: NestedScrollView.sliverOverlapAbsorberHandleFor(
                        context),
                  ),
                  SliverPadding(
                    padding: const EdgeInsets.all(8.0),
                    sliver: SliverList(
                      delegate: SliverChildBuilderDelegate(
                        (BuildContext context, int index) {
                          return Column(
                            children: <Widget>[
                              Container(
                                height: 150,
                                width: double.infinity,
                                color: Colors.blueGrey,
                                child: Column(
                                  mainAxisAlignment: MainAxisAlignment.center,
                                  children: <Widget>[
                                    Text('${widget.tabName} $index')
                                  ],
                                ),
                              ),
                              SizedBox(
                                height: 8,
                              )
                            ],
                          );
                        },
                        childCount: 30,
                      ),
                    ),
                  ),
                ],
              ),
            ),
          );
        },
      ),
    );
  }

  @override
  bool get wantKeepAlive => true;
}
fluttercandies / extended_nested_scroll_view

the internal elastic scroll is not clean by extended_nested_scroll_view #62
