How to use select box related on another select box?

Question

How to use related select boxes in Symfony ?

Let\'s say, I have a select list containing compagnies and another containing employees of the selected company. How do I d

Answer 1

I had the same problem. You must use form events. My code example with country, region, city relations.

namespace Orfos\UserBundle\Form\Type;

///import form events namespace
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\Form\FormEvents;
use Symfony\Component\Form\Event\DataEvent;

class RegistrationFormType extends BaseType
{

    private $request;

    public function __construct($class, $request, $doctrine)
    {
        parent::__construct($class);
        $this->request = $request;
        $this->doctrine = $doctrine;
    }

    public function buildForm(FormBuilder $builder, array $options)
    {
        parent::buildForm($builder, $options);
        //other fields

        $locale = $this->request->getLocale();

        $builder->add('country', 'entity', array(
            'class' => 'Orfos\CoreBundle\Entity\Country',
            'property' => $locale . 'name',
            'label' => 'register.country.label',
            'query_builder' => function(EntityRepository $er) {
                return $er->createQueryBuilder('c')
                                ->select('c', 't')
                                ->join('c.translations', 't');
            },
        ));

        $factory = $builder->getFormFactory();
        $refreshRegion = function ($form, $country) use ($factory, $locale) {
                    $form->add($factory->createNamed('entity', 'region', null, array(
                                'class' => 'Orfos\CoreBundle\Entity\Region',
                                'property' => $locale . 'name',
                                'label' => 'register.region.label',
                                'query_builder' => function (EntityRepository $repository) use ($country) {
                                    $qb = $repository->createQueryBuilder('region')
                                            ->select('region', 'translation')
                                            ->innerJoin('region.country', 'country')
                                            ->join('region.translations', 'translation');

                                    if ($country instanceof Country) {
                                        $qb = $qb->where('region.country = :country')
                                                ->setParameter('country', $country);
                                    } elseif (is_numeric($country)) {
                                        $qb = $qb->where('country.id = :country_id')
                                                ->setParameter('country_id', $country);
                                    } else {
                                        $qb = $qb->where('country.id = 1');
                                    }

                                    return $qb;
                                }
                            )));
                };
        $factory = $builder->getFormFactory();
        $refreshCity = function($form, $region) use ($factory, $locale) {
                    $form->add($factory->createNamed('entity', 'city', null, array(
                                'class' => 'Orfos\CoreBundle\Entity\City',
                                'property' => $locale . 'name',
                                'label' => 'register.city.label',
                                'query_builder' => function (EntityRepository $repository) use ($region) {
                                    $qb = $repository->createQueryBuilder('city')
                                            ->select('city', 'translation')
                                            ->innerJoin('city.region', 'region')
                                            ->innerJoin('city.translations', 'translation');

                                    if ($region instanceof Region) {
                                        $qb = $qb->where('city.region = :region')
                                                ->setParameter('region', $region);
                                    } elseif (is_numeric($region)) {
                                        $qb = $qb->where('region.id = :region_id')
                                                ->setParameter('region_id', $region);
                                    } else {
                                        $qb = $qb->where('region.id = 1');
                                    }

                                    return $qb;
                                }
                            )));
                };

        $builder->addEventListener(FormEvents::PRE_SET_DATA, function (DataEvent $event) use ($refreshRegion, $refreshCity) {
                    $form = $event->getForm();
                    $data = $event->getData();

                    if ($data == null){
                        $refreshRegion($form, null);
                        $refreshCity($form, null);
                    }

                    if ($data instanceof Country) {
                        $refreshRegion($form, $data->getCountry()->getRegions());
                        $refreshCity($form, $data->getRegion()->getCities());
                    }
                });

        $builder->addEventListener(FormEvents::PRE_BIND, function (DataEvent $event) use ($refreshRegion, $refreshCity) {
                    $form = $event->getForm();
                    $data = $event->getData();

                    if (array_key_exists('country', $data)) {
                        $refreshRegion($form, $data['country']);
                    }
                    if (array_key_exists('region', $data)) {
                        $refreshCity($form, $data['region']);
                    }                    
                });
    }

}