Android.Xamarin.SampleApp.WithUIActivity.payTokenPreAuth_Click C# (CSharp) Method

        private void payTokenPreAuth_Click (object sender, EventArgs e)
        {

            if (string.IsNullOrWhiteSpace (cardToken) || string.IsNullOrWhiteSpace (lastFour)) {
                Toast.MakeText (this,
                    "Can't make a Preauth token payment before making a full preauth card payment to save card token",
                    ToastLength.Short).Show ();
                return;
            }

            Judo.Instance.TokenPreAuth (GetTokenCardViewModel (), SuccessPayment, FailurePayment, this);

         
        }