SF2 Form Event Subscriber that replace non submitted values by the default.

1_ReplaceNotSubmittedValuesByDefaultsListener.php

<?php

use Symfony\Component\Form\FormEvent;
use Symfony\Component\Form\FormFactoryInterface;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\Form\FormEvents;

/**
 * ReplaceNotSubmittedValuesByDefaultsListener
 *
 * @author Adrien Brault <[email protected]>
 */
class ReplaceNotSubmittedValuesByDefaultsListener implements EventSubscriberInterface
{
    private $factory;
    private $ignoreRequiredFields;

    public function __construct(FormFactoryInterface $factory, $ignoreRequiredFields = true)
    {
        $this->factory = $factory;
        $this->ignoreRequiredFields = $ignoreRequiredFields;
    }

    /**
     * {@inheritdoc}
     */
    public static function getSubscribedEvents()
    {
        return array(FormEvents::PRE_BIND => 'preBind');
    }

    /**
     * {@inheritdoc}
     */
    public function preBind(FormEvent $event)
    {
        $form = $event->getForm();
        $submittedData = $event->getData();

        if ($form->getConfig()->getCompound()) {
            foreach ($form->all() as $name => $child) {
                if (!isset($submittedData[$name])
                    && (!$this->ignoreRequiredFields || !$child->isRequired())) {
                    $submittedData[$name] = $child->getData();
                }
            }
        }

        $event->setData($submittedData);
    }
}

2_FormType.php

<?php

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;
use Symfony\Component\OptionsResolver\OptionsResolverInterface;
use JMS\DiExtraBundle\Annotation as DI;

use XXXBundle\Form\EventListener\ReplaceNotSubmittedValuesByDefaultsListener;

/**
 * @DI\FormType
 */
class CollectionType extends AbstractType
{
    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $subscriber = new ReplaceNotSubmittedValuesByDefaultsListener($builder->getFormFactory());
        $builder->addEventSubscriber($subscriber);

        $builder->add('page', 'hidden', array('required' => false, 'attr' => array(
            'id' => 'page',
        )));
        $builder->add('limit', 'hidden', array('required' => false, 'attr' => array(
            'id' => 'limit',
        )));
    }

    public function getName()
    {
        return 'XXX_rest_collection';
    }
}