Firebase listener not getting called

Question

I want to check whether node is created or not. I just implemented below called with Toast but nothing toasting at all.

note: firebase DataBase is Total null now

  DatabaseReference reference = FirebaseDatabase.getInstance().getReference();

    reference.addListenerForSingleValueEvent(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            Toast.makeText(RegisterActivity.this, dataSnapshot.getKey() + "", Toast.LENGTH_SHORT).show();
        }

        @Override
        public void onCancelled(DatabaseError databaseError) {
            Toast.makeText(RegisterActivity.this, databaseError.toString() + "", Toast.LENGTH_SHORT).show();
        }
    });

secondly below code i tried but no luck

 DatabaseReference reference = FirebaseDatabase.getInstance().getReference();

    reference.child("device_id");

    reference.addListenerForSingleValueEvent(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            Toast.makeText(RegisterActivity.this, dataSnapshot.getKey() + "", Toast.LENGTH_SHORT).show();

        }

        @Override
        public void onCancelled(DatabaseError databaseError) {
            Toast.makeText(RegisterActivity.this, databaseError.toString() + "", Toast.LENGTH_SHORT).show();


        }
    });

"firebase DataBase is Total null now" - does that mean you don't have any data on your database? — Rosário Pereira Fernandes, Mar 18 '18 at 09:50
You might want to have a look at [this answer](https://stackoverflow.com/a/41832659/5861618) — Rosário Pereira Fernandes, Mar 18 '18 at 09:52

score 0 · Answer 1 · answered Mar 19 '18 at 12:48

0

Change this line of code:

reference.addListenerForSingleValueEvent(new ValueEventListener() {

with:

reference.child("device_id").addListenerForSingleValueEvent(new ValueEventListener() {

answered Mar 19 '18 at 12:48

Alex Mamo

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Firebase listener not getting called

1 Answers1