Symfony form - Access Entity inside child entry Type in a CollectionType

Question

I\'m trying to access the entity for a given embedded form in the parent CollectionType inside FormBuilder:

ParentType

Answer 1

The answer lies in using Event Listeners which listen for the PRE_SET_DATA event.

It will pass your closure a FormEvent class which contains both the form and the data being bound to it.

public function buildForm(FormBuilderInterface $builder, array $options)
{
    $builder->addEventListener(FormEvents::PRE_SET_DATA,
        function (FormEvent $event) use ($builder)
        {
            $form = $event->getForm();
            $child = $event->getData();

            if ($child instanceof Child) {

                // Do what ever you like with $child entity data

            }
        }
    );
}