Symfony实体表单，包含来自另一个实体的动态字段

Question

问题：

请考虑以下订单表单：

META DATA:

Title:       [________]

REQUIREMENTS:

What size?  [_] Small    [_] Medium    [_] Large
What shape?  [_] Circle    [_] Square    [_] Triangle
.
.
.

如何生成表单？

约束：

• size＆amp; shape＆amp;应从另一个名为...。
的实体中检索Requirement

我的想法：

顺序

Class Order
{
    private $title;

    //OneToMany(targetEntity="Requirement", mappedBy="order")
    private $requirements;

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

要求

Class Requirement
{
    private $title;

    //ManyToOne(targetEntity="Order", inversedBy="requirements")
    private $order;

    //OneToMany(targetEntity="Selection", mappedBy="selections")
    private $selections;

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

}

选择

Class Selection
{
    private $title;

    //ManyToOne(targetEntity="Requirement", inversedBy="selections")
    private $requirement;
}

订单类型

class OrderType extends AbstractType
{
    public function configureOptions(OptionsResolver $resolver)
    {
        $resolver->setDefaults(array(
            'allow_extra_fields' => true
        ));
        $resolver->setRequired('em');
    }

    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $em = $options['em'];
        $requirements = $em->getRepository(Requirement::class)->findAll();

        $form = $builder
            ->add('title', TextType::class, array());

        foreach ($requirements as $requirement) {

            $args['label']         = $requirement->getTitle();
            $args['expanded']      = true;
            $args['multiple']      = true;
            $args['mapped']        = false;
            $args['class']         = Selection::class;
            $args['choice_label']  = 'title';
            $args['choice_value']  = 'id';
            $args['query_builder'] = call_user_func(function (EntityRepository $er, $requirement) {
                    return $er->createQueryBuilder('s')
                        ->where('s.requirement = :requirement')
                        ->setParameter('requirement', $requirement)
                },$em->getRepository($args['class']), $requirement);

            $form
                ->add($requirement->getTitle(), EntityType::class, $args);

        }

        $form
            ->add('submit', SubmitType::class, array(();

        return $form;
    }
}

问题：

这很好用，我可以坚持新的Order。问题在于编辑Order，如

$form->createView()

正确填写订单title时，不会更新选择（复选框）。我甚至不知道这是否是在Symfony上这样做的正确方法。我不知道在渲染编辑实体表单时如何重新填充选中的复选框。

注意：

我不认为Symfony Form Collections是否是一个好主意，因为要求在时间上发生变化且无法硬编码为FormType，因此应存储在数据库中。