How do I stop Symfony 2 checkbox from returning null

Question

On my Symfony 2 form I have 2 checkboxes. The documentation states

"if the box is checked, the field will be set to true, if the box is unchecked, the value will be set to false"

which is what I'd like to happen but when the checkbox is unchecked I'm actually getting nothing back. I realise a checkbox on a HTML form will normally return nothing if unchecked and I'd usually add some logic to the back end to handle it but it sounds like Symfony should be doing that for me and isn't.

What am I doing wrong or have I missed?

My formtype looks like this:

public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder->add('fullname', 'text')
            ->add('screened', 'checkbox', array(
                'label'     => 'Enable screening emails?' ))
            ->add('dedupe', 'checkbox', array(
                'label'     => 'Enable live dedupeing?'))
 );)

and the relevant bits of the twig template look like this:

<div class="form-group">
    <div class="input-group col-sm-offset-2 col-sm-10">
        <div class="checkbox col-sm-6">
            {{ form_widget(form.screened) }}
            {{ form_label(form.screened) }}
        </div>
        <div class="checkbox col-sm-6">
            {{ form_widget(form.dedupe, {'attr': {'required': 'false'}}) }}
            {{ form_label(form.dedupe) }}
        </div>

    </div>
</div>

The form is created in the controler here:

/**
     * Creates a new User entity.
     *
     */
    public function createAction(Request $request)
    {
        $entity = new User();
        $form = $this->createCreateForm($entity);
        $form->handleRequest($request);

        if ($form->isValid()) {
            $em = $this->getDoctrine()->getManager();
            $this->get('project_login.user_manager')->setUserPassword($entity, $form->get('password')->getData());

            $em->persist($entity);
            $em->flush();

            return $this->redirect($this->generateUrl('user_show', array('id' => $entity->getId())));
        }

        return $this->render('ProjectLoginBundle:User:new.html.twig', array(
            'entity' => $entity,
            'form'   => $form->createView(),
        ));
    }

    /**
     * Creates a form to create a User entity.
     *
     * @param User $entity The entity
     *
     * @return \Symfony\Component\Form\Form The form
     */
    private function createCreateForm(User $entity)
    {
        $form = $this->createForm(new UserType(), $entity, array(
            'action' => $this->generateUrl('user_create'),
            'method' => 'POST', 'validation_groups' => array('create')
        ));

        $form->add('submit', 'submit', array('label' => 'Create'));

        return $form;
    }

Answer 1

If I understood well you need to handle when the field is not checked, because you're not getting a response when you're handling the form request

You can solve it in this way:

 if ($form->isValid()) {
     $form->handleRequest($request);

     $em = $this->getDoctrine()->getManager();

     $entity = $form->getData();

     var_dump($entity->getScreened());
     var_dump($entity->getFullname());
     var_dump($entity->getDedupe());

     // They should return you the values set on the create form
     $em->persist($entity);
     $em->flush();
 }

In case that it is not getting the values try in this way, but is not the proper one...

if (!isset($form->get('screened')) {
    $entity->setScreened(false);
}

if (!isset($form->get('dedupe')) {
    $entity->setDedupe(false);
}

It will check if you're not receiving any data for dedupe and screened from the form, if it's this case you'll know that the value has not been checked