Firebase Offline Capabilities and addListenerForSingleValueEvent

Question

Whenever I use addListenerForSingleValueEvent with setPersistenceEnabled(true), I only manage to get a local offline copy of DataSnapshot

Answer 1

When workinkg with persistence enabled, I counted the times the listener received a call to onDataChange() and stoped to listen at 2 times. Worked for me, maybe helps:

private int timesRead;
private ValueEventListener listener;
private DatabaseReference ref;

private void readFB() {
    timesRead = 0;
    if (ref == null) {
        ref = mFBDatabase.child("URL");
    }

    if (listener == null) {
        listener = new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {
                //process dataSnapshot

                timesRead++;
                if (timesRead == 2) {
                    ref.removeEventListener(listener);
                }
            }

            @Override
            public void onCancelled(DatabaseError databaseError) {
            }
        };
    }
    ref.removeEventListener(listener);
    ref.addValueEventListener(listener);
}