private function _getSelectedCustomFieldTypes(array $aSubject = array())
{
$_aCheckedCustomFieldTypes = $this->oFactory->oUtil->getElementAsArray($_POST, array($this->oFactory->oProp->sOptionKey, 'generator', 'custom_field_types'), array());
$_aCheckedCustomFieldTypes = array_intersect_key($aSubject, array_filter($_aCheckedCustomFieldTypes));
return $_aCheckedCustomFieldTypes;
}