private void DismissOrShowViewController(bool show, IViewController viewController) {
   if (show) {
     viewController.Show();
   } else {
     viewController.Dismiss();
   }
 }
 private void DismissOrShowViewController(bool show, IViewController viewController)
 {
     if (show)
     {
         viewController.Show();
     }
     else
     {
         viewController.Dismiss();
     }
 }