控制器 - 没有访问类 - 实体

Question

我得到了这个错误消息，但我不明白为什么。

Neither the property "categories" nor one of the methods "addCategory()"/"removeCategory()", "setCategories()", "categories()", "__set()" or "__call()" exist and have public access in class "Checkout\Bundle\ItemBundle\Entity\Item". 

的事情是，在我的实体 “项” 我真的有这一切东西：

/** 
* @ORM\ManyToMany(targetEntity="Checkout\Bundle\ItemBundle\Entity\Category", mappedBy="items") 
**/ 
private $categories; 

和

/** 
* Add categories 
* 
* @param Category $categories 
* @return Item 
*/ 
public function addCategory(Category $categories) 
{ 
    $this->categories[] = $categories; 

    return $this; 
} 

/** 
* Remove categories 
* 
* @param Category $categories 
*/ 
public function removeCategory(Category $categories) 
{ 
    $this->categories->removeElement($categories); 
} 

/** 
* Get categories 
* 
* @return \Doctrine\Common\Collections\Collection 
*/ 
public function getCategories() 
{ 
    return $this->categories; 
} 

好吧，好吧 - 什么是我的控制器？

/** 
* Creates a new Item entity. 
* 
* @Route("/create", name="item_create") 
* @param Request $request 
* @return \Symfony\Component\HttpFoundation\Response 
*/ 
public function createAction(Request $request) 
{ 
    $entity = new Item(); 
    $currentUser = $this->getUser(); 

    $form = $this->createFormBuilder($entity) 
     ->add('name', null, array(
      'label' => 'Item Name', 
      'required' => true, 
     )) 
     ->add('categories', 'entity', array(
      'label' => 'Select a Category', 
      'required' => false, 
      'class' => 'CheckoutItemBundle:Category', 
      'property' => 'name', 
      'query_builder' => function (EntityRepository $er) use ($currentUser) { 
       return $er->createQueryBuilder('c') 
        ->where('c.user = :user') 
        ->setParameter('user', $currentUser); 
      }, 
     )) 

     ->add('submit', 'submit', array('label' => 'Speichern')) 
     ->getForm(); 

    $form->handleRequest($request); 

    if ($form->isSubmitted() && $form->isValid()) { 
     $em = $this->getDoctrine()->getManager(); 
     $em->persist($entity); 
     $em->flush(); 


    } 

    return $this->render(
     'CheckoutItemBundle:Item:create.html.twig', 
     array(
      'entity' => 'entity', 
      'form' => $form->createView() 
     ) 
    ); 
} 

所以，最大的问题是，为什么他说他没有找到它，当它显然存在。任何想法？先谢谢你！

Answer 1

->add('categories', 'entity', array(
     'label' => 'Select a Category', 
     'required' => false, 
     'class' => 'CheckoutItemBundle:Category', 
     'property' => 'name', 
     'multiple' => true, 
     'query_builder' => function (EntityRepository $er) use ($currentUser) { 
      return $er->createQueryBuilder('c') 
       ->where('c.user = :user') 
       ->setParameter('user', $currentUser); 
     }, 
    )) 

您有多对多的关系，但您的表单需要多对一。要解决此问题，需要将multiple设置为true。