在Symfony2中嵌入集合类型

Question

Trying to embed a collection type, basically following the step by step approach here .

I get the following error:

The form's view data is expected to be an instance of class
AppBundle\Entity\BenefitGroup, but is an instance of class 
AppBundle\Entity\BenefitItem. You can avoid this error by setting the 
"data_class" option to null or by adding a view transformer that transforms 
an instance of class AppBundle\Entity\BenefitItem to an instance of 
AppBundle\Entity\BenefitGroup.

Just to clarify, the BenefitItem is the father while the BenefitGroup is the child.

I'm getting this error, basically.

I've not implemented (yet) the part that allows you to add BenefitGroup elements dynamically, and I'm not even trying to persist the object or remove it (so I did not implement yet the last part of the Doctrine as explained in the example).

Here is my code:

The BenefitItem entity:

<?php
// src/AppBundle/Entity/BenefitItem.php

namespace AppBundle\Entity;

use Doctrine\ORM\Mapping as ORM;
use Doctrine\Common\Collections\ArrayCollection;

/**
 * @ORM\Entity(repositoryClass="AppBundle\Entity\BenefitItemRepository")
 * @ORM\Table(name="benefit_items")
 */
class BenefitItem
{
/**
 * @ORM\Column(type="integer")
 * @ORM\Id
 * @ORM\GeneratedValue(strategy="AUTO")
 */
protected $id;

/**
 * @ORM\Column(type="string", length=400)
 */
protected $comment;

public function __construct()
{
    $this->BenefitGroups = new ArrayCollection();
}

public function getBenefitGroups()
{
    return $this->BenefitGroups;
}

/**
 * Get id
 *
 * @return integer 
 */
public function getId()
{
    return $this->id;
}

/**
 * Set comment
 *
 * @param string $comment
 * @return BenefitItem
 */
public function setComment($comment)
{
    $this->comment = $comment;

    return $this;
}

/**
 * Get comment
 *
 * @return string 
 */
public function getComment()
{
    return $this->comment;
}
}

The BenefitGroup entity:

<?php
// src/AppBundle/Entity/BenefitGroup.php

namespace AppBundle\Entity;

use Doctrine\ORM\Mapping as ORM;

/**
 * @ORM\Entity(repositoryClass="AppBundle\Entity\BenefitGroupRepository")
 * @ORM\Table(name="benefit_groups")
 */
class BenefitGroup
{
/**
 * @ORM\Column(type="integer")
 * @ORM\Id
 * @ORM\GeneratedValue(strategy="AUTO")
 */
protected $id;

/**
 * @ORM\Column(type="string", length=100)
 */
protected $name;

/**
 * @ORM\ManyToOne(targetEntity="BenefitItem", cascade={"persist"})
 * @ORM\JoinColumn(name="benefitItem_id")
 */
protected $benefitItem;


/**
 * Get id
 *
 * @return integer 
 */
public function getId()
{
    return $this->id;
}

/**
 * Set name
 *
 * @param string $name
 * @return BenefitGroup
 */
public function setName($name)
{
    $this->name = $name;

    return $this;
}

/**
 * Get name
 *
 * @return string 
 */
public function getName()
{
    return $this->name;
}

/**
 * Set benefitItem
 *
 * @param \AppBundle\Entity\BenefitItem $benefitItem
 * @return BenefitGroup
 */
public function setBenefitItem(\AppBundle\Entity\BenefitItem $benefitItem = null)
{
    $this->benefitItem = $benefitItem;

    return $this;
}

/**
 * Get benefitItem
 *
 * @return \AppBundle\Entity\BenefitItem 
 */
public function getBenefitItem()
{
    return $this->benefitItem;
}
}

The BenefitItemFormType:

<?php

namespace AppBundle\Form\Type;

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;
use Symfony\Component\OptionsResolver\OptionsResolverInterface;

class BenefitItemFormType extends AbstractType
{
public function buildForm(FormBuilderInterface $builder, array $options)
{
    $builder->add('comment');

    $builder->add('benefitgroups', 'collection', array('type' => new BenefitGroupFormType()));
}

public function setDefaultOptions(OptionsResolverInterface $resolver)
{
    $resolver->setDefaults(array(
        'data_class' => 'AppBundle\Entity\BenefitGroup',
    ));
}

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

The BenefitGroupFormType:

<?php

namespace AppBundle\Form\Type;

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;
use Symfony\Component\OptionsResolver\OptionsResolverInterface;

class BenefitGroupFormType extends AbstractType
{
public function buildForm(FormBuilderInterface $builder, array $options)
{
    $builder->add('name');
}

public function setDefaultOptions(OptionsResolverInterface $resolver)
{
    $resolver->setDefaults(array(
        'data_class' => 'AppBundle\Entity\BenefitGroup',
    ));
}

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

The controller:

<?php
// AppBundle\Controller\BenefitController.php

namespace AppBundle\Controller;
use Sensio\Bundle\FrameworkExtraBundle\Configuration\Route;
use AppBundle\Entity\BenefitItem;
use AppBundle\Entity\BenefitGroup;
use AppBundle\Form\Type\BenefitItemFormType;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Bundle\FrameworkBundle\Controller\Controller;

class BenefitController extends Controller
{
/**
 * @Route("/benefit/show", name="benefit_show")
 */
public function showAction(Request $request)
{
    $BI = new BenefitItem();

    $BG1 = new BenefitGroup();
    $BG1->setName = 'Name 1';
    $BI->getBenefitGroups()->add($BG1);
    $BG2 = new BenefitGroup();
    $BG2->setName = 'Name 2';
    $BI->getBenefitGroups()->add($BG2);        

    $form = $this->createForm(new BenefitItemFormType(), $BI);

    $form->handleRequest($request);

    if ($form->isValid()) {
        // ... maybe do some form processing, like saving the Task and Tag objects
    }

    return $this->render('benefit/show.html.twig', array(
        'form' => $form->createView(),
    ));
}
}

Any idea?

Answer 1

You say, your data_class is a BenefitGroup

$resolver->setDefaults(array(
    'data_class' => 'AppBundle\Entity\BenefitGroup',
));

Then you set a BenefitItem .

$BI = new BenefitItem();
// ...
$form = $this->createForm(new BenefitItemFormType(), $BI);

That cannot work. I didn't check the rest of your code, but that's also what the exception says.