code: public boolean isSingleDataImage()
      {
      	if (this.getScreenField().getConverter() != null)
          	if (this.getScreenField().getConverter().getField() != null)
              	if (this.getScreenField().getConverter().getField().getComponent(1) == null)
      		return true;
      	return false;
      }
docs: Special case - if this button is linked to data and this is the only sfield, then display it.
  @return