Adding data from firebase causes an infinite loop

Question

Pleas help, I have a problem when I want to add user point data from a Firebase database

I want to add the previous user's point to the newly obtained point. This is the code that I use

final DatabaseReference userDataRef = FirebaseDatabase.getInstance().getReference().child("Users").child(userRefEmail);
    userDataRef.addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
            String userCurrentPoint = dataSnapshot.child("point").getValue().toString();

            if (userCurrentPoint != null) {
                int finalPoint = Integer.parseInt(userCurrentPoint) + poin;
                userDataRef.child("point").setValue(String.valueOf(finalPoint));
            }
        }
        @Override
        public void onCancelled(@NonNull DatabaseError databaseError) {
        }
    });

But when I use it, there is an infinite continuous addition of points to the firebase database, how do I deal with this?

Answer 1

Use SingleValueEvent instead of ValueEventListener , with SingleValueEvent it will only be called once:

    userDataRef.addListenerForSingleValueEvent(new ValueEventListener() {
        @Override
        public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
            String userCurrentPoint = dataSnapshot.child("point").getValue().toString();

            if (userCurrentPoint != null) {
                int finalPoint = Integer.parseInt(userCurrentPoint) + poin;
                userDataRef.child("point").setValue(String.valueOf(finalPoint));
            }
        }
        @Override
        public void onCancelled(@NonNull DatabaseError databaseError) {
        }
    });