我知道IndexedStack的目的是一次显示缓存中的一个小部件，以防止小部件被重新构建。
但在某些情况下，必须更新小部件中的数据。
现在考虑下面的代码示例，假设我希望在点击Increment选项卡时重新生成第1页（即：每当我从“递减”选项卡切换到“递增”选项卡时）：
home.dart

class HomePage extends StatefulWidget {
  @override
  _HomePageState createState() => _HomePageState();
}

class _HomePageState extends State<HomePage> {
  List<Widget> pages = [Page1(), Page2()];
  int selectedIndex = 0;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Save Page State'),
      ),  

      body: IndexedStack(
        index: selectedIndex,
        children: pages,
      ),

      bottomNavigationBar: BottomNavigationBar(
        items: [
          BottomNavigationBarItem(
            icon: Icon(Icons.plus_one_outlined),
            label: 'Increment',
          ),  
          BottomNavigationBarItem(
            icon: Icon(Icons.exposure_minus_1_outlined),
            label: 'Decrement',
          ),  
        ],  
        currentIndex: selectedIndex,
        onTap: (index){
            setState(() {
                selectedIndex = index;
            }); 
        },  
      ),  
    );  
  }
}

page1.dart

class Page1 extends StatefulWidget {
  @override
  _Page1State createState() => _Page1State();

}

class _Page1State extends State<Page1> {
  int count = 0;

  @override
  Widget build(BuildContext context) {

    return Column(
      mainAxisAlignment: MainAxisAlignment.spaceAround,
      children: [
        Center(
          child: Text(
            '$count',
            style: Theme.of(context).textTheme.headline2,
          ),  
        ),  
        ElevatedButton(
          onPressed: () {
            setState(() {
              count++;
            }); 
          },  
          child: Text('Increment'),
        )   
      ],  
    );  
  }
}

page2.dart

class Page2 extends StatefulWidget {
  @override
  _Page2State createState() => _Page2State(); 
} 

class _Page2State extends State<Page2> {
  int count = 0;               

  @override
  Widget build(BuildContext context) {
    return Column(             
      mainAxisAlignment: MainAxisAlignment.spaceAround,
      children: [              
        Center(
          child: Text(
            '$count',          
            style: Theme.of(context).textTheme.headline2,
          ),                   
        ),                     
        ElevatedButton(        
          onPressed: () {      
            setState(() {      
              count--;
            });
          },
          child: Text('Decrement'),
        )
      ],
    );
  }
}

我该怎么做？
我尝试从列表中删除Page1小部件，然后使用removeAt和insert再次添加它，但它不起作用。
有什么想法？