Formulario dinamicos

public function addAction()
    {
        $em = $this->get('doctrine.orm.entity_manager');
 
        $formtype = new PromocionType('\Eros\ExtranetBundle\Form\Model\Promocion','1');
        $form = $this->get('form.factory')->create($formtype);
        $formHandler = new PromocionFormHandler($form,$this->get('request'));
        $process = $formHandler->process($em);
        if ($process) {
            return new RedirectResponse($this->container->get('router')->generate('_profile_edit'));
        }
         return $this->render('ErosExtranetBundle:Promociones:promocionesdetails.html.twig', array('form' => $form->createView(),'articulos'=>null));
    }