如果ListView由FutureBuilder组成，为什么PageStorageKey不工作？

class MyListView extends StatefulWidget {
  @override
  _MyListViewState createState() => _MyListViewState();
}

class _MyListViewState extends State<MyListView> with AutomaticKeepAliveClientMixin {
  Future<List<String>> _getData() async {
    // 获取数据的异步操作
  }

  @override
  bool get wantKeepAlive => true;

  @override
  Widget build(BuildContext context) {
    super.build(context); // 必须调用super.build

    return FutureBuilder<List<String>>(
      future: _getData(),
      builder: (context, snapshot) {
        if (snapshot.connectionState == ConnectionState.waiting) {
          return CircularProgressIndicator();
        } else if (snapshot.hasError) {
          return Text('Error: ${snapshot.error}');
        } else {
          return ListView.builder(
            key: PageStorageKey('myListView'), // 设置PageStorageKey
            itemCount: snapshot.data.length,
            itemBuilder: (context, index) {
              return ListTile(
                title: Text(snapshot.data[index]),
              );
            },
          );
        }
      },
    );
  }
}