Flutter Tab Crash #11895

test.dart

import 'package:flutter/material.dart';

void main() {
  runApp(TabBarDemo());
}

class TabBarDemo extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: DefaultTabController(
        length: 4,
        child: Scaffold(
          appBar: AppBar(
            bottom: TabBar(
              tabs: [
                Tab(icon: Icon(Icons.directions_car)),
                Tab(icon: Icon(Icons.directions_transit)),
                Tab(icon: Icon(Icons.directions_bike)),
                Tab(icon: Icon(Icons.directions_boat)),
              ],
            ),
            title: Text('Tabs Demo'),
          ),
          body: TabBarView(
            children: [
              StateTest(),
              Icon(Icons.directions_transit),
              Icon(Icons.directions_bike),
              Icon(Icons.directions_boat),
            ],
          ),
        ),
      ),
    );
  }
}
class StateTest extends StatefulWidget
{
  @override
  State<StatefulWidget> createState() {
    return new StateTestState();
  }
}

class StateTestState extends State<StateTest> with AutomaticKeepAliveClientMixin
{
  @override
  Widget build(BuildContext context) {
    return Icon(Icons.directions_car);
  }

  @override
  bool get wantKeepAlive => true;
}