在Flutter中有没有一种方法可以只允许动态生成的ListView的一个ExpansionTile被扩展？

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

class _MyListViewState extends State<MyListView> {
  List<Item> _items = List.generate(10, (index) => Item('Item $index', 'Content $index'));
  int _expandedIndex = -1;

  @override
  Widget build(BuildContext context) {
    return ListView(
      children: _items.map<Widget>((Item item) {
        final index = _items.indexOf(item);
        final isExpanded = index == _expandedIndex;

        return ExpansionPanelList(
          elevation: 1,
          expandedHeaderPadding: EdgeInsets.all(0),
          expansionCallback: (int index, bool isExpanded) {
            setState(() {
              _expandedIndex = isExpanded ? -1 : index;
            });
          },
          children: [
            ExpansionPanel(
              headerBuilder: (BuildContext context, bool isExpanded) {
                return ListTile(
                  title: Text(item.title),
                );
              },
              body: ListTile(
                title: Text(item.content),
              ),
              isExpanded: isExpanded,
            ),
          ],
        );
      }).toList(),
    );
  }
}

class Item {
  Item(this.title, this.content);

  String title;
  String content;
}