Firebase firestore 查询不会过滤数据，即使在 flutter 中使用 where 时也是如此

Question

I'm trying to use where in a Firebase firestore query in my flutter application but it is showing all the data in the collection without filtering it., here is my code:

  Widget buildingMessages() {
    print('message room id $roomID'); //The correct id is being printed here
    var theMessages = FirebaseFirestore.instance.collection('messages');
    theMessages.where('room_id',isEqualTo: roomID).orderBy('created', descending: true);
    return StreamBuilder<QuerySnapshot>(
      stream: theMessages.snapshots(),
      builder: (BuildContext context, AsyncSnapshot<QuerySnapshot> snapshot) {
        if (snapshot.hasError) {
          return Text('Something went wrong');
        }

        return new ListView(
          children: snapshot.data.docs.map((DocumentSnapshot document) {
//....

Answer 1

The problem is in stream: theMessages.snapshots() . You are referencing the theMessages . and you are not using your where clause. extends it with your where clause. like

stream: theMessages.snapshots().where(
                  'room_id',isEqualTo: roomID).orderBy('created', descending: true);

Edit: Or initialize it as

var theMessages = FirebaseFirestore.instance.collection('messages').
            where('room_id',isEqualTo: roomID).orderBy('created', descending: true);