How can I connect a device to my Android firebase database

Question

I am fairly new to Android development. I am working on an app which I have connected to a firebase database and everything works fine. Now I am trying to connect a device which will send a like an attendance details of each users when they clock in on that device to the firebase database. Do I need a http interface to do this or an API

Answer 1

Try this

Declare few variables:

private FirebaseUser user;
private FirebaseDatabase database;
private DatabaseReference mRef;

Initialise them inside onCreate or somewhere:

    user = FirebaseAuth.getInstance().getCurrentUser();
    database = FirebaseDatabase.getInstance();
    mRef = database.getReference("users").child(user.getUid()).child("attendance"); //different path for each user

Add value event listener

mRef.addListenerForSingleValueEvent(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {

                Integer attendance = dataSnapshot.getValue(Integer.class);
                attendance++;
                myRef.setValue(attendance);
                }
            }

            @Override
            public void onCancelled(DatabaseError databaseError) {

            }
        });

Answer 2

No you don't need any http interface to read and write value to firebase database . You can refer to official documentation here