<?php
namespace AppBundle\Controller;

use Symfony\Bundle\FrameworkBundle\Controller\Controller;
use Sensio\Bundle\FrameworkExtraBundle\Configuration\Route;
use AppBundle\Model\Example;
use AppBundle\Model\Form\Type\ExampleType;

class ExampleController extends Controller
{
    /**
     * @Route("/")
     * @return \Symfony\Component\HttpFoundation\RedirectResponse
     */
    public function indexAction()
    {
        $example = new Example();
        $example->value = 'disabled';
      
        $form = $this->createForm(ExampleType::class, $example);
        
        ...
    }
}