public function getClassNameForUpDownArrow($field, $dbOrdering)
    {
        $className = '';
        if (is_array($dbOrdering) && count($dbOrdering)) {
            if ($field == $dbOrdering[0]) {
                if ($dbOrdering[1] == 'asc') {
                    $className = 'up';
                } else {
                    $className = 'down';
                }
            }
        }
        return $className;
    }