如何从firebase实时数据库中获取int型数据

Question

I have tried to get the value of an int type from my database but it returns a null value i used a future to prevent that but still same problem it returns null

I tried calling the method inside the build function and also outside the build even went a step further to call it inside initState but no success whats the problem?

Widget build(BuildContext context){...}
int getSnapShotDataAsInt(String child){
  FutureBuilder(
    future: databaseReference
      .child("users")
      .child(_firebaseUser.uid)
      .child(child)
      .once(),
    builder: (BuildContext context, AsyncSnapshot snapshot) {
      if (snapshot.hasData && snapshot.data != null) {
        return snapshot.data.value;
      } else {
        return CircularProgressIndicator();
      }
    }
  );
}

Answer 1

I believe the issue is your ".value", the correct call as per documentation is:

return snapshot.data.val();

I believe you can optionally pass a data type into those brackets to attempt conversion to specific data type. Such as:

return snapshot.data.val(String); (etc)

https://firebase.google.com/docs/reference/node/firebase.database.DataSnapshot#val