public function setPlain($plain) { if (!isset($this->plainMimePart)) { $this->plainMimePart = \Swift_MimePart::newInstance($plain, 'text/plain'); } else { $this->emailObj->detach($this->plainMimePart); $this->plainMimePart->setBody($plain); } if (!empty($plain)) { $this->emailObj->attach($this->plainMimePart); } }