public function build($newsletterId)
    {
        require_once JPATH_ROOT . DS . 'components' . DS . 'com_newsletter' . DS . 'models' . DS . 'cron.php';
        $this->_model = new NewsletterModelCron();
        $params = JComponentHelper::getParams("com_newsletter");

        $newsletter = $this->_model->getNewsletter($newsletterId);
        $attachments = $this->_model->getAttachments($newsletterId);

        $urlNewsletter = JURI::root() . 'images/newsletter/';

        $mail = JFactory::getMailer();

        ob_start();
        require JPATH_ROOT . DS . 'components' . DS . 'com_newsletter' . DS . 'views' . DS . 'cron' . DS . 'tmpl' . DS .'default.php';
        $htmlContent = trim(ob_get_contents());
        ob_end_clean();

        $mail->setBody($htmlContent);
        $mail->IsHTML();
        $mail->AltBody = $newsletter->nonhtmlcontent;
        $mail->setSubject($newsletter->title);
        $mail->SetFrom($params->get('email_from'));
        foreach ($attachments as $attachment) {
            $mail->addAttachment(JPATH_ROOT . $attachment->path);
        }

        return $mail;
    }