protected override void OnCreate(Bundle savedInstanceState) { base.OnCreate(savedInstanceState); // Create your application here SetContentView(Resource.Layout.layout2); FirebaseAuth mAuth = FirebaseAuth.Instance; FirebaseUser user = mAuth.CurrentUser; if (user == null) { var result = mAuth.SignInAnonymously(); } FirebaseDatabase database = FirebaseDatabase.Instance; dbRef = database.GetReference("mygallery"); FirebaseStorage storage = FirebaseStorage.Instance; //create child reference StorageReference storageRef = storage.Reference; imagesRef = storageRef.Child("images"); Button btn = FindViewById <Button>(Resource.Id.createdb); btn.Click += Btn_Click; }