Issue in rendering collection of forms in Symfony 2.0 - php

Question

I have the following User entity:
class User extends BaseUser implements ParticipantInterface
{
/**
* #Exclude()
* #ORM\OneToMany(targetEntity="App\MainBundle\Entity\PreferredContactType", mappedBy="user", cascade={"all"})
*/
protected $preferredContactTypes;
/**
* Add preferredContactType
*
* #param \App\MainBundle\Entity\PreferredContactType $preferredContactType
* #return User
*/
public function addPreferredContactTypes(\App\MainBundle\Entity\PreferredContactType $preferredContactType)
{
$this->preferredContactTypes[] = $preferredContactType;
return $this;
}
/**
* Remove preferredContactType
*
* #param \App\MainBundle\Entity\PreferredContactType $preferredContactType
*/
public function removePreferredContactTypes(\App\MainBundle\Entity\PreferredContactType $preferredContactType)
{
$this->preferredContactTypes->removeElement($preferredContactType);
}
/**
* Get preferredContactType
*
* #return \App\MainBundle\Entity\PreferredContactType
*/
public function getPreferredContactTypes()
{
return $this->preferredContactTypes;
}
}
I wanted to create a form that displays multiple choices of the preferredContactType:
$contactOptions = $em->getRepository('AppMainBundle:ContactType')->findAll();
$settingsForm = $this->createForm(new UserType(), $user, array(
'contact' => $contactOptions,
));
and here's what my UserType looks like:
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder->add('preferredContactTypes', 'collection', array('type' => 'choice', 'options' => array('choices' => $options['contact'], 'multiple' => true, 'expanded' => true)))
;
}
but now I am getting an error of:
Expected an array.
How do I solve this?

Answer 1

It fails because you pass to choices parameter instance of ArrayCollection class (that was returned in $em->getRepository('AppMainBundle:ContactType')->findAll();). But choices parameter need to be array (http://symfony.com/doc/2.0/reference/forms/types/choice.html#choices).
You can use toArray() method on your ArrayCollection to retrieve the array but it will not give the expected result because it will be array of instances of ContactType.
The best way to form some choice list from entity is to use entity type instead of choice. See more here: http://symfony.com/doc/current/reference/forms/types/entity.html.
Also you can implement Symfony\Component\Form\Extension\Core\ChoiceList\ChoiceListInterface in some class and use it as parameter choice_list in choice form field. For example you can extend Symfony\Component\Form\Extension\Core\ChoiceList\LazyChoiceList and implement loadChoiceList() method.