/** * Add the campaign id * * @param $campaign_id * * @return mixed|void * @author Nicolas Juen */ public static function get_header_titles($campaign_id) { self::$header_titles = apply_filters('bea_sender_csv_headers', array('Id', 'Email', 'Current status', 'Bounce cat', 'Bounce type', 'Bounce no'), $campaign_id); return self::$header_titles; }