我在 getuserinformation 中的 DataSnapShot 中遇到错误

Question

here is the code

     static void getCurrentOnlineUserInformation()async{
  User user = _firebaseAuth.currentUser;
  String userid = user.uid;
  DatabaseReference reference = FirebaseDatabase.instance.ref().child('userProfile');
  reference.child(userid).once().then((DataSnapshot dataSnapshot){
  }
  );
  }

but its not fetching DataSnapShot

Error error: The argument type 'Null Function(DataSnapshot)' can't be assigned to the parameter type 'FutureOr Function(DatabaseEvent)'. (argument_type_not_assignable at [themovers] lib\assistants\assistantmethods.dart:86)

its getting null value again and again

here is live code error

here is database

here is the model

Answer 1

By default.then accepts dynamic parameter but if you wish to pass different parameter then you have change Function(dynamic) to Function(YOURTYPE) try below code:

static void getCurrentOnlineUserInformation()async{
  User user = _firebaseAuth.currentUser;
  String userid = user.uid;
  DatabaseReference reference = 
        FirebaseDatabase.instance.ref().child('userProfile');
         reference.child(userid).once().then(<DataSnapshot>(DataSnapshot dataSnapshot){
        }
      );
  }