src/XQueue/Maileon/API/Mailings/MailingsService.php
function addCustomProperties($mailingId, $properties) {

        $xml = new SimpleXMLElement("<?xml version=\"1.0\"?><properties></properties>");

        if (is_array($properties)) {
            foreach ($properties as $property) {
                $this->sxml_append($xml, $property->toXML());
            }
        } else {
            $this->sxml_append($xml, $properties->toXML());
        }

        return $this->post("mailings/${mailingId}/settings/properties", $xml->asXML());
    }
function addCustomProperties($mailingId, $properties) {

        $xml = new SimpleXMLElement("<?xml version=\"1.0\"?><properties></properties>");

        if (is_array($properties)) {
            foreach ($properties as $property) {
                $this->sxml_append($xml, $property->toXML());
            }
        } else {
            $this->sxml_append($xml, $properties->toXML());
        }

        return $this->post("mailings/${mailingId}/settings/properties", $xml->asXML());
    }
Adds a list of custom properties to the mailing with the provided id.

@param int $mailingId
@param array $properties Array of com_maileon_api_mailings_CustomProperty or single property
@return com_maileon_api_MaileonAPIResult