参数类型'Stream<dynamic>'不能分配给参数类型"流<QuerySnapshot>？

Question

我收到一个错误"无法将参数类型"Stream"分配给参数类型"Stream？"运行此代码时：

import 'package:app_using_database/post.dart';
import 'package:flutter/material.dart';
import 'package:firebase_auth/firebase_auth.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
class Home extends StatelessWidget {
Stream postStream =
FirebaseFirestore.instance.collection('posts').snapshots();
@override
Widget build(BuildContext context) {
return Scaffold(
body: Container(
padding: EdgeInsets.symmetric(horizontal: 10),
child: SafeArea(
child: StreamBuilder<QuerySnapshot>(
stream: postStream,
builder:
(BuildContext context, AsyncSnapshot<QuerySnapshot> snapshot) {
if (snapshot.hasError) {
return Text('Something went wrong');
}
if (snapshot.connectionState == ConnectionState.waiting) {
return Text("Loading");
}
return new ListView(
children: snapshot.data!.docs.map((DocumentSnapshot document) {
Map<String, dynamic> data =
document.data() as Map<String, dynamic>;
return Post();
}).toList(),
);
},
),
),
),
);
}
}

我正试图从firebase获得帖子，但出现了这个错误。它还说

• "流"来自"dart:async">
• "QuerySnapshot"来自"package:cloud_firestore/cloud_firestore.dart">

Answer 1

将其更改为此

CollectionReference posts = FirebaseFirestore.instance.collection('posts');
.
.
.
stream: posts.snapshots()