Обратитесь к Users/Driver
и l oop через детей, вы получите свой ключ:
DatabaseReference mDatabase = FirebaseDatabase.getInstance().getReference().child("Users").child("Driver");
ValueEventListener listener = new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
//loop through the children
for(DataSnapshot ds: dataSnapshot.getChildren()){
//get the key or keys depending on how many keys
String underLinedKey = ds.getKey();
}
}
@Override
public void onCancelled(DatabaseError databaseError) {
//log error
Log.w(TAG, "loadPost:onCancelled", databaseError.toException());
}
};
mDatabase.addValueEventListener(listener);