如何在 flutter Firestore 中将数组返回为 stream？

Question

I'm trying to return a post array from firestore as a stream in flutter.

return Scaffold(
  body: StreamBuilder<QuerySnapshot>(
    stream: FirebaseFirestore.instance
        .collection('groups')
        .doc(groupId)
        .snapshots(),
    builder: (_, snapshot) {
      if (snapshot.hasData) {
        final docs = snapshot.data!.docs;

        return ListView.builder(
            itemCount: querySnapshot.docs.length,
            itemBuilder: ((context, i) {
              final docdata = docs[i].data();
              return ListTile();
            }));
      } else {
        return Text('wait');
      }
      ;
    },
  ),
);

Answer 1

Query returns a single document ie a stream with DocumentSnapshot type instead of QuerySnapshot .

  StreamBuilder<DocumentSnapshot>(
    stream: FirebaseFirestore.instance
        .collection('groups')
        .doc(groupId)
        .snapshots(),
    builder: (_, snapshot) {
...
    },
  ),