Symfony - 通过表单将一个主要实体链接到第二个实体

Question

I am currently using doctrine wrong as when I have a choiceType in my entity, I use this:

    /**
    * @ORM\Column(type="integer")
    */
    private $type;

plus in my builder:

    ->add('type', ChoiceType::class, ['choices' => ['Pattern' => 0, 'Image' => 1]])

I would like now to have something cleaner and have another entity in my database that would be linked to this main entity. Here is what I did.

1. Created a "category" entity (and created in DB):

    /**
    * @ORM\Entity(repositoryClass="App\Repository\CategoryRepository")
    * @ORM\Table(name="vipbox_mep_category")
    */
    class Category {
        /**
        * @ORM\Id
        * @ORM\Column(type="integer")
        * @ORM\GeneratedValue(strategy="AUTO")
        */
        private $id;
   
       /**
        * @ORM\Column(type="string", length=255)
        */
       private $category;
   
       /**
        * @return mixed
        */
       public function getCategory()
       {
           return $this->category;
       }
   
       /**
        * @param mixed $category
        */
       public function setCategory($category): void
       {
           $this->category = $category;
       }
   }
   

2. linked my main entity to the second one (with the getter and setter):

   /**
    * @ORM\OneToOne(targetEntity="App\Entity\Category")
    */
   private $category;
   

3. Added my category to my form:

   ->add('category', CategoryType::class, ['required' => true, 'label' => 'Category'])
   

4. Extended AbstractType form for my category:

   class CategoryType extends AbstractType
   {
       /**
        * @var RouterInterface $route
        */
       private $router;
   
       /**
        * @param RouterInterface $router
        */
       public function __construct(RouterInterface $router)
       {
          $this->router = $router;
       }
   
       /**
        * {@inheritdoc}
        */
       public function configureOptions(OptionsResolver $resolver)
       {
           $resolver->setDefaults([
               'required' => true,
               'label' => 'Category'
           ]);
       }
   
       /**
        * {@inheritdoc}
       */
       public function getParent()
       {
           return ChoiceType::class;
       }
   }
   

5. Populated my Category table with text sample data (2 rows)

6. Tested to show my form, I does compute, but I have an empty choiceType:

I know I missed one/multiple things on my way, any clues ?

Answer 1

Assuming you have saved some data in your Category table to populate your drop-down list just change your step 3 from this:

->add('category', CategoryType::class, ['required' => true, 'label' => 'Category'])

to this:

->add('category', EntityType::class, [
    'class' => Category::class,
    'required' => true,
    'label' => 'Category',
])

There are lots of other options available for EntityType, see the docs.