如何将列表返回给StreamBuilder？

import 'dart:async';
import 'package:flutter/material.dart';

class MyListScreen extends StatefulWidget {
  @override
  _MyListScreenState createState() => _MyListScreenState();
}

class _MyListScreenState extends State<MyListScreen> {
  StreamController<List<String>> _listController;

  @override
  void initState() {
    super.initState();
    _listController = StreamController<List<String>>.broadcast();
    // 模拟异步获取数据
    fetchData();
  }

  @override
  void dispose() {
    _listController.close();
    super.dispose();
  }

  void fetchData() async {
    // 模拟异步获取数据
    await Future.delayed(Duration(seconds: 2));
    List<String> data = ['Item 1', 'Item 2', 'Item 3'];
    _listController.add(data);
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('My List'),
      ),
      body: StreamBuilder<List<String>>(
        stream: _listController.stream,
        builder: (BuildContext context, AsyncSnapshot<List<String>> snapshot) {
          if (snapshot.hasData) {
            List<String> data = snapshot.data;
            return ListView.builder(
              itemCount: data.length,
              itemBuilder: (BuildContext context, int index) {
                return ListTile(
                  title: Text(data[index]),
                );
              },
            );
          } else if (snapshot.hasError) {
            return Text('Error: ${snapshot.error}');
          } else {
            return Center(child: CircularProgressIndicator());
          }
        },
      ),
    );
  }
}