无法使用Cloud Firestore和Flutter在ListView内部获取

import 'package:cloud_firestore/cloud_firestore.dart';

void main() {
  // 初始化 Firestore
  FirebaseFirestore firestore = FirebaseFirestore.instance;

  // 后续代码...
}

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

class MyListView extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return StreamBuilder<QuerySnapshot>(
      stream: FirebaseFirestore.instance.collection('your_collection').snapshots(),
      builder: (BuildContext context, AsyncSnapshot<QuerySnapshot> snapshot) {
        if (snapshot.hasError) {
          return Text('获取数据时出错: ${snapshot.error}');
        }

        if (snapshot.connectionState == ConnectionState.waiting) {
          return Text('加载中...');
        }

        return ListView(
          children: snapshot.data.docs.map((DocumentSnapshot document) {
            Map<String, dynamic> data = document.data() as Map<String, dynamic>;
            return ListTile(
              title: Text(data['title']),
              subtitle: Text(data['subtitle']),
            );
          }).toList(),
        );
      },
    );
  }
}