Symfony2 DataTransformer for choice field - php

Question

I'm trying to create a custom choice list field.
And almost all seems working, except the preselected values on the edit part.
Basically i'm creating a mixed list field with multiple object type (the backend is mongodb), i know that is a dirty way to operate but i didn't find a better solution (keeping things simple).
The process is working, i have a mixed objects in the backend and i can choose which one in the edit form, but the form doesn't show the preselected (with the values extracted from mongo)
<?php
namespace www\DefaultBundle\Form\Type;
use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;
use www\DefaultBundle\Form\DataTransformer\AccessorioTransformer;
use Doctrine\Common\Persistence\ObjectManager;
use Symfony\Component\OptionsResolver\OptionsResolverInterface;
class AccessorioType extends AbstractType
{
/**
* #var ObjectManager
*/
private $om;
/**
* #param ObjectManager $om
*/
public function __construct(ObjectManager $om)
{
$this->om = $om;
}
public function buildForm(FormBuilderInterface $builder, array $options)
{
$transformer = new AccessorioTransformer($this->om);
$builder->addModelTransformer($transformer);
}
public function setDefaultOptions(OptionsResolverInterface $resolver)
{
$choices = array();
$data = array();
$documents = array(
'Document1',
'Document2',
'Document3',
);
foreach ($documents as $document)
{
$objects = $this->om->getRepository('wwwDefaultBundle:' . $document)->findAll();
foreach ($objects as $object)
{
if (#!$object->getId()) print_r($object);
$key = sprintf("%s_%s", $object->getId(), basename(str_replace('\\', '/', get_class($object))));
$value = sprintf("%s (%s)", $object, basename(str_replace('\\', '/', get_class($object))));
$choices[$key] = $value;
}
}
$resolver->setDefaults(array(
'choices' => $choices,
'expanded' => false,
'multiple' => true,
));
}
public function getParent()
{
return 'choice';
}
public function getName()
{
return 'accessorio';
}
}
the datatransformer:
<?php
namespace www\DefaultBundle\Form\DataTransformer;
use Symfony\Component\Form\DataTransformerInterface;
use Symfony\Component\Form\Extension\Core\ObjectChoiceList;
use Symfony\Component\Form\Exception\TransformationFailedException;
use Doctrine\Common\Persistence\ObjectManager;
use Acme\TaskBundle\Entity\Issue;
class AccessorioTransformer implements DataTransformerInterface
{
/**
* #var ObjectManager
*/
private $om;
/**
* #param ObjectManager $om
*/
public function __construct(ObjectManager $om)
{
$this->om = $om;
}
public function transform($values)
{
return array();
// i tried everything here but none working
}
public function reverseTransform($values)
{
if (!$values) return null;
$array = array();
foreach ($values as $value)
{
list($id, $type) = explode("_", $value);
$array[] = $this->om->getRepository('wwwDefaultBundle:' . $type)->find($id);
}
return $array;
}
}
the form builder:
<?php
namespace www\DefaultBundle\Form;
use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;
use Symfony\Component\OptionsResolver\OptionsResolverInterface;
class ValvolaType extends AbstractType
{
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder
// [snip]
->add('ref',
'accessorio',
array(
'label_attr' => array('class' => 'control-label col-sm-2'),
'attr' => array('class' => 'form-control '),
))
;
}
public function setDefaultOptions(OptionsResolverInterface $resolver)
{
$resolver->setDefaults(array(
'data_class' => 'www\DefaultBundle\Document\Valvola',
'attr' => array('class' => 'press form-horizontal'),
));
}
public function getName()
{
return 'www_defaultbundle_valvolatype';
}
}
Did someone faced the same problem? How "choice" field should be transformed? How managed mixed object in the same field?
Someone can enlighten me?
Regards

Answer 1

I finally found the solution. The culprit was the datatransformer (and mine, of course :-))
In this way the form shows the preselected values:
<?php
namespace www\DefaultBundle\Form\DataTransformer;
use Symfony\Component\Form\DataTransformerInterface;
use Symfony\Component\Form\Extension\Core\ObjectChoiceList;
use Symfony\Component\Form\Exception\TransformationFailedException;
use Doctrine\Common\Persistence\ObjectManager;
use Acme\TaskBundle\Entity\Issue;
class AccessorioTransformer implements DataTransformerInterface
{
/**
* #var ObjectManager
*/
private $om;
/**
* #param ObjectManager $om
*/
public function __construct(ObjectManager $om)
{
$this->om = $om;
}
public function transform($values)
{
if ($values === null) return array();
$choices = array();
foreach ($values as $object)
{
$choices[] = sprintf("%s_%s", $object->getId(), basename(str_replace('\\', '/', get_class($object))));
}
return $choices;
}
public function reverseTransform($values)
{
if (!$values) return array();
$array = array();
foreach ($values as $value)
{
list($id, $type) = explode("_", $value);
$array[] = $this->om->getRepository('wwwDefaultBundle:' . $type)->find($id);
}
return $array;
}
}

Answer 2

In most cases using ChoiceType the array returned by the transform function should contain the ID's only. For example:
public function transform($objectsArray)
{
$choices = array();
foreach ($objectsArray as $object)
{
$choices[] = $object->getId();
}
return $choices;
}
Although it might not be the answer to the original post, I am pretty sure that googlers get here and look for this hint.