@Override
 public void onStringSet(StringPicker stringPicker, String value) {
   DialogFragmentCallback listener = getDialogFragmentCallback();
   if (listener != null) {
     listener.onStringSet(this, stringPicker, value);
   }
 }
 @Override
 public void onNumberSet(NumberPicker numberPicker, int value) {
   DialogFragmentCallback listener = getDialogFragmentCallback();
   if (listener != null) {
     listener.onNumberSet(self, numberPicker, value);
   }
 }