Symfony2 Dynamic / Dependent Forms

Question

I have a form with 3 dependent fields:

Manufacturer → ManufacturerProductGroup → ManufacturerProductSeries

So, I want to choose a manufacturer based on the ProductGroup manufacturer and based on the ProductGroup product series.

There is a CookBook entry on how to deal with such dynamic forms; it works easily for ManufacturerProductGroup. The problem is that ManufacturerProductSeries is dependent on a different dynamic shape / field.

The problem is that I cannot add the Listener to the closure, since I only have access to FormInterface no longer to FormBuilderInterface.

I can’t do this with only one listener, as in the PRE_SET_DATA listener, since the form will be sent next, which will prevent any changes. I need a way to add a listener dynamically or perhaps update only the data in the POST_SUBMIT listener and not replace the entire field / form.

This is the code that gives the error, as I add a listener to a form field that does not exist (producerProductGroup is available only after the pre_set_data event)

/**
 * @param FormBuilderInterface $builder
 * @param array                $options
 */
public function buildForm(FormBuilderInterface $builder, array $options)
{
    $builder
        ->add('manufacturer', 'entity', array('class' => 'ArticleBundle:manufacturer', 'empty_value' => false));

    $manufacturerProductGroupModifier = function(FormInterface $form, Manufacturer $manufacturer)
    {
        $manufacturerProductGroups = $this->em->getRepository('ArticleBundle:ManufacturerProductGroup')
            ->findAvailableByManufacturer($manufacturer);

        $form->add(
            'manufacturerProductGroup',
            'entity',
            array(
                'class' => 'ArticleBundle:ManufacturerProductGroup',
                'empty_value' => '',
                'choices' => $manufacturerProductGroups
            )
        );
    };

    $manufacturerProductSeriesModifier = function(FormInterface $form, ManufacturerProductGroup $manufacturerProductGroup)
    {
        $manufacturerProductSeries = $this->em->getRepository('ArticleBundle:ManufacturerProductSeries')
            ->findAvailableByManufacturerProductGroup($manufacturerProductGroup);

        $form->add(
            'manufacturerProductSeries',
            'entity',
            array(
                'class' => 'ArticleBundle:ManufacturerProductSeries',
                'empty_value' => '',
                'choices' => $manufacturerProductSeries
            )
        );

    };

    $builder->addEventListener(
        FormEvents::PRE_SET_DATA,
        function(FormEvent $event) use ($manufacturerProductGroupModifier, $manufacturerProductSeriesModifier) {
            /** @var $article Article */
            $article = $event->getData();
            $manufacturerProductGroupModifier($event->getForm(), $article->getManufacturer());
            $manufacturerProductSeriesModifier($event->getForm(), $article->getManufacturerProductGroup());
        }
    );

    $builder->get('manufacturer')->addEventListener(
        FormEvents::POST_SUBMIT,
        function(FormEvent $event) use ($manufacturerProductGroupModifier) {
            $manufacturer = $event->getForm()->getData();
            $manufacturerProductGroupModifier($event->getForm()->getParent(), $manufacturer);
        }
    );

    $builder->get('manufacturerProductGroup')->addEventListener(
        FormEvents::POST_SUBMIT,
        function(FormEvent $event) use ($manufacturerProductSeriesModifier) {
            $manufacturerProductGroup = $event->getForm()->getData();
            $manufacturerProductSeriesModifier($event->getForm()->getParent(), $manufacturerProductGroup);
        }
    );
}

Answer 1

I solved the issue with the following code:

    $addManufacturerProductSeries = function (FormEvent $event) {
        $form = $event->getForm()->getParent();
        $manufacturerProductGroup = $event->getData();

        $form->add(
            'manufacturerProductSeries',
            'entity',
            array(
                'auto_initialize' => false,
                'class' => 'ArticleBundle:ManufacturerProductSeries',
                'query_builder' => function (ManufacturerProductSeriesRepository $repository) use ($manufacturerProductGroup) {
                    return $repository->findAvailableByManufacturerProductGroupQueryBuilder($manufacturerProductGroup);
                },
            )
        );
    };

    $addManufacturerProductGroup = function (FormEvent $event) use ($factory, $addManufacturerProductSeries) {
        $form = $event->getForm()->getParent();
        $manufacturer = $event->getData();

        $fieldBuilder = $factory->createNamedBuilder(
            'manufacturerProductGroup',
            'entity',
            null,
            array(
                'auto_initialize' => false,
                'class' => 'ArticleBundle:ManufacturerProductGroup',
              'query_builder' => function (ManufacturerProductGroupRepository $repository) use ($manufacturer) {
                    return $repository->findAvailableByManufacturerQueryBuilder($manufacturer);
                },
            )
        );

        $fieldBuilder->addEventListener(FormEvents::POST_SET_DATA, $addManufacturerProductSeries);
        $fieldBuilder->addEventListener(FormEvents::POST_SUBMIT, $addManufacturerProductSeries);

        $form->add($fieldBuilder->getForm());
    };

    $builder->get('manufacturer')->addEventListener(FormEvents::POST_SET_DATA, $addManufacturerProductGroup);
    $builder->get('manufacturer')->addEventListener(FormEvents::POST_SUBMIT, $addManufacturerProductGroup);