Firebase 如何使用StreamBuilder获取特定的Firestore文档
这是我当前使用的设置:Firebase 如何使用StreamBuilder获取特定的Firestore文档,firebase,firebase-realtime-database,flutter,google-cloud-firestore,Firebase,Firebase Realtime Database,Flutter,Google Cloud Firestore,这是我当前使用的设置: class BookList extends StatelessWidget { @override Widget build(BuildContext context) { return StreamBuilder<QuerySnapshot>( stream: Firestore.instance.collection('books').snapshots(), builder: (BuildContext cont
class BookList extends StatelessWidget {
@override
Widget build(BuildContext context) {
return StreamBuilder<QuerySnapshot>(
stream: Firestore.instance.collection('books').snapshots(),
builder: (BuildContext context, AsyncSnapshot<QuerySnapshot> snapshot) {
if (snapshot.hasError)
return new Text('Error: ${snapshot.error}');
switch (snapshot.connectionState) {
case ConnectionState.waiting: return new Text('Loading...');
default:
return new ListView(
children: snapshot.data.documents.map((DocumentSnapshot document) {
return new ListTile(
title: new Text(document['title']),
subtitle: new Text(document['author']),
);
}).toList(),
);
}
},
);
}
}
问题是我不知道如何在Streambuilder中使用该示例。当我尝试这样做时:
...
body: StreamBuilder<QuerySnapshot>(
stream: Firestore.instance
.collection('talks')
.document('document-name')
.get()
.then((DocumentSnapshot ds) {
// use ds as a snapshot
}),
builder: (BuildContext context, AsyncSnapshot<QuerySnapshot> snapshot) {
if (snapshot.data == null)
return Center(child: CircularProgressIndicator());
if (snapshot.hasError) return new Text('Error: ${snapshot.error}');
if (snapshot.data.documents.length == 0)
...
。。。
正文:StreamBuilder(
流:Firestore.instance
.collection(‘talks’)
.document(“document-name”)
.get()
.然后((文档快照){
//将ds用作快照
}),
生成器:(BuildContext上下文,异步快照){
如果(snapshot.data==null)
返回中心(子项:CircularProgressIndicator());
if(snapshot.hasError)返回新文本('Error:${snapshot.Error}');
if(snapshot.data.documents.length==0)
...
我得到:
无法将参数类型“Future”分配给参数类型“Stream”。dart(参数类型不可分配)
在Firestore的Flatter库中,您可以通过调用获取单个文档的流 比如:
stream: Firestore.instance.collection('books').document('document-name').snapshots(),
在Firestore的Flatter库中,您可以通过调用获取单个文档的流 比如:
stream: Firestore.instance.collection('books').document('document-name').snapshots(),
谢谢你,我可以使用你的参考资料并将我的QuerySnapshot更改为DocumentSnapshot谢谢你,我可以使用你的参考资料并将我的QuerySnapshot更改为DocumentSnapshot