Method assetgroups

/**
 * Gets a list of the asset groups as an array of JHtml compatible options.
 *
 * @return  mixed  An array or false if an error occurs
 *
 * @since   1.6
 */
public static function assetgroups()
{
    if (empty(static::$asset_groups)) {
        $db = Factory::getDbo();
        $query = $db->getQuery(true)->select([$db->quoteName('a.id', 'value'), $db->quoteName('a.title', 'text')])->from($db->quoteName('#__viewlevels', 'a'))->group([$db->quoteName('a.id'), $db->quoteName('a.title'), $db->quoteName('a.ordering')])->order($db->quoteName('a.ordering') . ' ASC');
        $db->setQuery($query);
        static::$asset_groups = $db->loadObjectList();
    }
    return static::$asset_groups;
}