使用 FormEvents::POST_SUBMIT 的两个监听器答案

【问题标题】：Use two listeners of FormEvents::POST_SUBMIT使用 FormEvents::POST_SUBMIT 的两个监听器
【发布时间】：2021-05-14 07:43:17
【问题描述】：

我想根据提交的数据修改一些表单字段，所以在表单类中我做了：

    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder->add('year', ChoiceType::class, [
                'choices' => ['Year' => '-1'] + array_combine(range(date('Y'), date('Y') - 19), range(date('Y'), date('Y') - 19)),
                'label' => false,
            ])
            ->add('make', ChoiceType::class, ['choices' => ['Make' => '-1'], 'label' => false])
            ->add('model', ChoiceType::class, ['choices' => ['Model' => '-1'], 'label' => false]);

        //...

        $builder->get('year')->addEventListener(
            FormEvents::POST_SUBMIT,
            function (FormEvent $event) {
                $year = $event->getForm()->getData();
                $makes = $year === '-1' ? ['Make' => '-1'] : $this->customService->getMakes();
                $event->getForm()->getParent()
                    ->add('make', ChoiceType::class, ['choices' => $makes, 'label' => false]);
            }
        );
        $builder->get('make')->addEventListener(
            FormEvents::POST_SUBMIT,
            function (FormEvent $event) {
                $make = $event->getForm()->getData();
                $models = $make === '-1'  ? ['Model' => '-1'] : $this->customService->getModels();
                $event->getForm()->getParent()
                    ->add('model', ChoiceType::class, ['choices' => $models, 'label' => false]);
            }
        );
    }

但是，即使我提交了make 字段，第二个侦听器也永远不会执行，因此我无法修改model 字段。有什么想法吗？

【问题讨论】：

标签： php symfony symfony-forms

【解决方案1】：

问题似乎是当修改year字段事件监听器中的make字段时，则永远不会调用make字段事件监听器。我找到了让它工作的方法：

    private $makes;
    private $models;

    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        //...

        $builder->get('year')->addEventListener(
            FormEvents::POST_SUBMIT,
            function (FormEvent $event) {
                $year = $event->getForm()->getData();
                $this->makes = $year === '-1' ? ['Make' => '-1'] : $this->customService->getMakes();
            }
        );
        $builder->get('make')->addEventListener(
            FormEvents::POST_SUBMIT,
            function (FormEvent $event) {
                $make = $event->getForm()->getData();
                $this->models = $make === '-1'  ? ['Model' => '-1'] : $this->customService->getModels();
                $event->getForm()->getParent()
                    ->add('make', ChoiceType::class, ['choices' => $this->makes, 'label' => false, 'data' => $make]);
            }
        );
        // Same with model field
    }

【讨论】：