TrickContoller.php

class TrickController extends Controller
{
    private $builder;

    public function __construct(TricksBuilder $builder)
    {
        $this->builder = $builder;
    }

    public function newTrickAction(Request $request)
    {
        // On crée le builder avec des valeurs par défaut
        $tricks = $this->builder
            ->create()
            ->withNom('votre nom ici')
            ->withDateCreation(new \DateTime())
            ->build();


        $form = $this->createForm(TricksType::class, $tricks);

        $form->handleRequest($request);

        if ($form->isSubmitted() && $form->isValid()) {

            $tricks = $form->getData();

            // Ajout du tricks en base de donnée
            $em = $this->getDoctrine()->getManager();
            $em->persist($tricks);
            $em->flush();

            return $this->render('confirm.html.twig', array('text' => 'Trick créé'));
        }

        return $this->render('formNewTrick.html.twig', array('form' => $form->createView(),
        ));
    }
}