如何从firebase中获取特定文档数据并以字符串形式返回

Question

I am trying to get a data in firestore like this:

am trying to get FCMToken from a user document And be able to immediately use it as a string inside a streambuilder

FirebaseFirestore.instance.collection("usersToken")
.doc(snapshot.data.docs[index].data()['userId'].toString())
.get();
//I don't know what to do from here on to be able to get it as a string

How do I do it?

Answer 1

It works for me

Widget build(BuildContext context) {
  return new StreamBuilder(
      stream: Firestore.instance.collection('COLLECTION_NAME').document('TEST').snapshots(),
      builder: (context, snapshot) {
        if (!snapshot.hasData) {
          return Center(child: CircularProgressIndicator());
        }
        var userDocument = snapshot.data;
        return new Text(userDocument["property_name"]);
      }
  );
}