public static ProcessScript GetInstance(View v)
        {
            if (instance == null)
            {
                instance = new ProcessScript(v);
            }

            return(instance);
        }
        protected override void OnCreate(Bundle savedInstanceState)
        {
            base.OnCreate(savedInstanceState);

            SetContentView(Resource.Layout.Main);

            handler = ProcessScript.GetInstance(Window.DecorView.RootView);
            bundle  = new Bundle();

            Button buttonSum = (Button)FindViewById(Resource.Id.buttonSum);

            editTextN1 = (EditText)FindViewById(Resource.Id.editTextN1);
            editTextN2 = (EditText)FindViewById(Resource.Id.editTextN2);

            buttonSum.Click += OnButtonSumClicked;
        }