通过RefreshIndicator在Flutter有状态小部件中使用FutureBuilder

class MyWidget extends StatefulWidget {
  @override
  _MyWidgetState createState() => _MyWidgetState();
}

class _MyWidgetState extends State<MyWidget> {
  Future<List<String>> fetchData() async {
    // 模拟异步加载数据
    await Future.delayed(Duration(seconds: 2));
    return ['Item 1', 'Item 2', 'Item 3'];
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('下拉刷新示例'),
      ),
      body: RefreshIndicator(
        onRefresh: () {
          // 下拉刷新回调函数
          return fetchData();
        },
        child: FutureBuilder<List<String>>(
          future: fetchData(),
          builder: (context, snapshot) {
            if (snapshot.connectionState == ConnectionState.waiting) {
              // 加载中
              return Center(
                child: CircularProgressIndicator(),
              );
            } else if (snapshot.hasError) {
              // 加载错误
              return Center(
                child: Text('加载失败'),
              );
            } else {
              // 加载成功
              return ListView.builder(
                itemCount: snapshot.data.length,
                itemBuilder: (context, index) {
                  return ListTile(
                    title: Text(snapshot.data[index]),
                  );
                },
              );
            }
          },
        ),
      ),
    );
  }
}