Add a Custom Entity with translations to Sylius

config.yml

doctrine:
    orm:
        resolve_target_entities:
            AppBundle\Entity\ProductCategoryInterface: AppBundle\Entity\ProductCategory

ProductCategory.orm.xml

// src/AppBundle/Resources/config/doctrine/ProductCategory.orm.xml
<?xml version="1.0" encoding="UTF-8"?>

<doctrine-mapping xmlns="http://doctrine-project.org/schemas/orm/doctrine-mapping"
                  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                  xsi:schemaLocation="http://doctrine-project.org/schemas/orm/doctrine-mapping
                                      http://doctrine-project.org/schemas/orm/doctrine-mapping.xsd">

    <mapped-superclass name="AppBundle\Entity\ProductCategory" table="app_product_category" repository-class="AppBundle\Entity\Repository\ProductCategoryRepository">
        <id name="id" column="id" type="integer">
            <generator strategy="AUTO" />
        </id>
    </mapped-superclass>

</doctrine-mapping>

ProductCategory.php

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

namespace AppBundle\Entity;

use Doctrine\Common\Collections\ArrayCollection;
use Sylius\Component\Resource\Model\TranslatableTrait;

class ProductCategory implements ProductCategoryInterface
{
    use TranslatableTrait {
        __construct as private initializeTranslationsCollection;
    }
    
    public function __construct()
    {
        $this->initializeTranslationsCollection();
    }
    
    /**
     * {@inheritdoc}
     */
    public function getName()
    {
        return $this->translate()->getName();
    }

    /**
     * {@inheritdoc}
     */
    public function setName($name)
    {
        $this->translate()->setName($name);
    }
}

ProductCategoryInterface.php

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

namespace AppBundle\Entity;

use Sylius\Component\Resource\Model\ResourceInterface;

interface ProductCategoryInterface extends
    ResourceInterface,
    ProductCategoryTranslationInterface
{

}

ProductCategoryRepository.php

// src/AppBundle/Entity/Repository/ProductCategoryRepository.php
<?php

namespace AppBundle\Entity\Repository;

use Sylius\Bundle\ResourceBundle\Doctrine\ORM\EntityRepository;

class ProductCategoryRepository extends EntityRepository implements ProductCategoryRepositoryInterface
{}

ProductCategoryRepositoryInterface.php

// src/AppBundle/Entity/Repository/ProductCategoryRepositoryInterface.php
<?php

namespace AppBundle\Entity\Repository;

interface ProductCategoryRepositoryInterface
{}

ProductCategoryTranslation.orm.xml

// src/AppBundle/Resources/config/doctrine/ProductCategoryTranslation.orm.xml
<?xml version="1.0" encoding="UTF-8" ?>

<doctrine-mapping xmlns="http://doctrine-project.org/schemas/orm/doctrine-mapping"
                  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                  xsi:schemaLocation="http://doctrine-project.org/schemas/orm/doctrine-mapping
                                      http://doctrine-project.org/schemas/orm/doctrine-mapping.xsd">

    <mapped-superclass name="AppBundle\Entity\ProductCategoryTranslation" table="app_product_category_translation" >
        <id name="id" column="id" type="integer">
            <generator strategy="AUTO" />
        </id>

        <field name="name" column="name" type="string" />
    </mapped-superclass>

</doctrine-mapping>

ProductCategoryTranslation.php

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

namespace AppBundle\Entity;

use Sylius\Component\Resource\Model\AbstractTranslation;

class ProductCategoryTranslation extends AbstractTranslation implements ProductCategoryTranslationInterface
{
    /**
     * @var string
     */
    protected $name;
    
    /**
     * {@inheritdoc}
     */
    public function getName()
    {
        return $this->name;
    }

    /**
     * {@inheritdoc}
     */
    public function setName($name)
    {
        $this->name = $name;
    }

}

ProductCategoryTranslationInterface.php

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

namespace AppBundle\Entity;

use Sylius\Component\Resource\Model\ResourceInterface;
use Sylius\Component\Resource\Model\SlugAwareInterface;

interface ProductCategoryTranslationInterface extends SlugAwareInterface, ResourceInterface
{
    /**
     * @return string
     */
    public function getName();

    /**
     * @param string $name
     */
    public function setName($name);
}

ProductCategoryTranslationType.php

// src/AppBundle/Form/Type/ProductCategoryTranslationType.php
<?php

namespace AppBundle\Form\Type;

use Sylius\Bundle\ResourceBundle\Form\Type\AbstractResourceType;
use Symfony\Component\Form\Extension\Core\Type\TextType;
use Symfony\Component\Form\FormBuilderInterface;

class ProductCategoryTranslationType extends AbstractResourceType
{
    /**
     * {@inheritdoc}
     */
    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder
            ->add('name', TextType::class, [
                'label' => 'sylius.form.product_category.name',
            ])
        ;
    }

    /**
     * {@inheritdoc}
     */
    public function getName()
    {
        return 'sylius_product_category_translation';
    }
}

ProductCategoryType.php

// src/AppBundle/Form/Type/ProductCategoryType.php
<?php

namespace AppBundle\Form\Type;

use Sylius\Bundle\ResourceBundle\Form\EventSubscriber\AddCodeFormSubscriber;
use Sylius\Bundle\ResourceBundle\Form\Type\AbstractResourceType;
use Sylius\Bundle\ResourceBundle\Form\Type\ResourceTranslationsType;
use Symfony\Component\Form\FormBuilderInterface;

class ProductCategoryType extends AbstractResourceType
{
    /**
     * {@inheritdoc}
     */
    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder
            ->add('translations', ResourceTranslationsType::class, [
                'type' => 'sylius_product_category_translation',
                'label' => 'sylius.form.product_category.name',
            ])
            ->addEventSubscriber(new AddCodeFormSubscriber())
        ;
    }

    /**
     * {@inheritdoc}
     */
    public function getName()
    {
        return 'sylius_product_category';
    }
}

services.yml

sylius_resource:
    resources:
        app.product_category:
            classes:
                model: AppBundle\Entity\ProductCategory
                interface: AppBundle\Entity\ProductCategoryInterface
                repository: AppBundle\Entity\Repository\ProductCategoryRepository
                form:
                    default: AppBundle\Form\Type\ProductCategoryType
            translation:
                classes:
                    model: AppBundle\Entity\ProductCategoryTranslation
                    interface: AppBundle\Entity\ProductCategoryTranslationInterface
                    form:
                        default: AppBundle\Form\Type\ProductCategoryTranslationType
                        
services:
    app.form.type.product_category:
        class: AppBundle\Form\Type\ProductCategoryType
        arguments: [ "%app.model.product_category.class%" ]
        tags:
            - { name: form.type, alias: sylius_product_category }
    app.form.type.product_category_translation:
        class: AppBundle\Form\Type\ProductCategoryTranslationType
        arguments: [ "%app.model.product_category_translation.class%" ]
        tags:
            - { name: form.type, alias: sylius_product_category_translation }