Flutter/ Firestore : Class 'QuerySnapshot' has no instance getter 'document' - firebase

Question

I have app that I want to retreive data which are messages represented in uid document from Firestore database as explained here and these messages stored like so :
ChatRoom->chatRoomId->chat-> uid-> messages
but I receive this error :
The following NoSuchMethodError was thrown building StreamBuilder(dirty, state: _StreamBuilderBaseState<dynamic,
AsyncSnapshot>#56cb5): Class 'QuerySnapshot' has no instance
getter 'document'. Receiver: Instance of 'QuerySnapshot' Tried
calling: document
The relevant error-causing widget was: StreamBuilder
file:///Users/ahmedhussain/Downloads/khamsat/Client%20Apps/HPX-KSA/hpx_ksa/lib/Screens/messages.dart:21:12
When the exception was thrown, this was the stack:
#0 Object.noSuchMethod (dart:core-patch/object_patch.dart:53:5)
#1 _MessagesState.chatRoomList. (package:hpxksa/Screens/messages.dart:25:38)
Here is my code:
class _MessagesState extends State<Messages> {
Stream chatRoomsStream;
Widget chatRoomList(){
return StreamBuilder(
stream: chatRoomsStream,
builder: (context, snapshot){
return snapshot.hasData ? ListView.builder(
itemCount: snapshot.data.document.length,
itemBuilder: (context, index){
return ChatRoomTile(
username: snapshot.data.documents[index].data["chatRoomId"]
.toString().replaceAll("_", "").replaceAll(Constants.myName, "replace"),
chatRoomId:snapshot.data.documents[index].data["chatRoomId"]
);
}) : Container();
}
);
}
getUserInfogetChats() {
DatabaseService().getChatRooms(Constants.myName).then((value) {
setState(() {
chatRoomsStream = value;
});
});
}
#override
void initState() {
getUserInfogetChats();
super.initState();
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(),
body: chatRoomList(),
);
}
}
class ChatRoomTile extends StatelessWidget {
final String username;
final String chatRoomId;
ChatRoomTile({this.username, this.chatRoomId});
#override
Widget build(BuildContext context) {
return GestureDetector(
onTap: (){
Navigator.push(context, MaterialPageRoute(builder: (context)=>Conversation(chatRoomId: chatRoomId,)));
},
child: Container(
color: Colors.black26,
padding: EdgeInsets.symmetric(horizontal: 24, vertical: 16),
child: Row(
children: <Widget>[
Container(
height: 40,
width: 40,
alignment: Alignment.center,
decoration: BoxDecoration(
color: kPrimaryColor,
borderRadius: BorderRadius.circular(40),
),
child: Text("${username.substring(0,1).toUpperCase()}"),
),
SizedBox(width: 8,),
Text(username),
],
),
),
);
}
}
Here is my get function to retreive chats that contains user name:
getChatRooms(String username)async{
return await Firestore.instance.collection("ChatRoom").
where("users", arrayContains: username).
snapshots();
}

Answer 1

The error that you received is quite clear about what the issue is. QuerySnapshot doesn't have a document property. You likely intended to use the documents property, which is more consistent with your attempt to use a ListView.
Changing instances of snapshot.data.document to snapshot.data.documents will solve this particular issue.

Answer 2

return StreamBuilder(
stream: chatRoomStream,
builder: (context, snapshot) {
return snapshot.hasData
? ListView.builder(
itemCount: snapshot.data.docs.length,
itemBuilder: (context, index) {
return ChatRoomTile(
**snapshot.data.docs[index].data()['chatRoomId']**);
},
)
: Container();
},
);