@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == REQUEST_CODE) {
            if (resultCode == Activity.RESULT_OK) {
                DropInResult result = data.getParcelableExtra(DropInResult.EXTRA_DROP_IN_RESULT);
                String payment_method_nonce=result.getPaymentMethodNonce().getNonce();
                submitNonce(payment_method_nonce);
                // use the result to update your UI and send the payment method nonce to your server
            } else if (resultCode == Activity.RESULT_CANCELED) {
                // the user canceled
            } else {
                // handle errors here, an exception may be available in
                Exception error = (Exception) data.getSerializableExtra(DropInActivity.EXTRA_ERROR);
            }
        }
    }