Rendering multiple forms on same page with Symfony 3

I’d like to show a login and a registration form on the same page. However it seems that we cannot render the same template with different form variables in different two actions in a controller.

Here is what I mean;

class SecurityController extends Controller { 
/**
 * @Route("/", name="login")
 */
public function loginAction(Request $request)
{

    //Check if the user is already authenticated
    if($this->container->get('security.authorization_checker')->isGranted('IS_AUTHENTICATED_FULLY')) {
        return $this->redirect($this->generateUrl('dashboard'));
    }

   $authenticationUtils = $this->get('security.authentication_utils');

    // get the  error if there is one
    $error = $authenticationUtils->getLastAuthenticationError();

    // last username entered by the user
    $lastUsername = $authenticationUtils->getLastUsername();

    $this->addFlash(
        'welcome',
        'Welcome back!'
    );

    return $this->render(
        '::landing.html.twig',
        array(
            // last username entered by the user
            'last_username' => $lastUsername,
            'error'         => $error,
        )
    );

    $registrationform = $this->get('form.factory')->createNamedBuilder('registrationform', UserType::class);
}

/**
 * @Route("/register", name="register")
 */
public function registerAction(Request $request)
{
    //Check authentication
    if($this->container->get('security.authorization_checker')->isGranted('IS_AUTHENTICATED_FULLY')) {
        return $this->redirect($this->generateUrl('dashboard'));
    }
    // get the authentication utils
    $authenticationUtils = $this->get('security.authentication_utils');
    // get the login error if there is one
    $error = $authenticationUtils->getLastAuthenticationError();
    // last username entered by the user
    $lastUsername = $authenticationUtils->getLastUsername();
    // build the form
    $user = new User();
    $form = $this->createForm(UserType::class, $user);
        // handle the submit (will only happen on POST)
        $form->handleRequest($request);
        if ($form->isSubmitted() && $form->isValid()) {
            $user->setRoles(array('ROLE_USER'));
            // Encode the password (you could also do this via Doctrine listener)
            $password = $this->get('security.password_encoder')
                ->encodePassword($user, $user->getPlainPassword());
            $user->setPassword($password);

            // save the User!
            $em = $this->getDoctrine()->getManager();
            $em->persist($user);
            $em->flush();

            $token = new UsernamePasswordToken($user, null, 'main', $user->getRoles());
            $this->get('security.token_storage')->setToken($token);
            $this->get('session')->set('_security_main', serialize($token));
            // ... do any other work - like sending them an email, etc
            // maybe set a "flash" success message for the user

            $this->addFlash(
                'success',
                'Please complete your profile now.'
            );

            $message = Swift_Message::newInstance()
                ->setSubject('You have successfully signed up!')
                ->setFrom('[e-mail]')
                ->setTo($user->getUsername())
                ->setBody($this->renderView(
                    ':emails:registration.html.twig'),'text/html');
            $this->get('mailer')->send($message);

            return $this->redirectToRoute('update');
        } else{
            $errors = $this->get('validator')->validate( $user );
        }

    return $this->render(
        '::landing.html.twig',
        array( 'form' => $form->createView(),
            'last_username' => $lastUsername,
            'error' => $error,
            )
    );
}

}

Above I have my login and registration action. I’d like to pass the ‘form’ variable to the same twig template that I render with login action. When I try to do that I’m getting the following exception.

Variable "form" does not exist in ::landing.html.twig at line 50
500 Internal Server Error - Twig_Error_Runtime

Answer

I would do it like this

2 twig files –

login.html.twig and register.html.twig – Every file render by himself the action

now the third twig file called baseLogin.html.twig

in this file, I render the two files (login and register) by calling controller

For example

baseLogin.html.twig

<div>
    {{ render(controller('UserBundle:Security:login')) }}
</div>

<div>
    {{ render(controller('UserBundle:Registration:register')) }}
</div>