Symfony: Get parent object within child from formevent - symfony

Question

I have a form that contains 3 fields (date, typeEvent, seller) where Seller is a choiceType that depends on date and typeEvent, and to do that i followed the symfony documentation for dynamics forms.
but the exemple in the doc its about a field that depends on only one other field.
what i did so far :
$formModifier = function (FormInterface $form,DateTime $date = null, TypeEvent $type = null) {
if (($date === null) || ($type === null)) {$sellers = [];return;}
$repo = $this->entityManager->getRepository(User::class);
$start = $date->format("Y-m-d H:i:s");
$end = new DateTime($date->format("Y-m-d H:i:s"));
$end = date_add($end,date_interval_create_from_date_string("60 minutes"))->format('Y-m-d H:i:s');
$organisation = $this->security->getUser()->getOrganisation();
$sellers = $repo->findSellers($organisation,$start,$end);
$form->add('seller', EntityType::class, [
'class' => User::class,
'placeholder' => '',
'choices' => $sellers,
'choice_label' => 'pseudo',
'attr' => ['class'=>'seller-select'],
'required'=>false,
'expanded' =>false,
]);
};
$builder->get('start')->addEventListener(
FormEvents::POST_SUBMIT,
function (FormEvent $event) use ($formModifier) {
$start = $event->getForm()->getData();
$type = $event->getForm()->getParent()->getData()->getTypeEvent();
$formModifier($event->getForm()->getParent(), $start, $type);
}
);
$builder->get('typeEvent')->addEventListener(
FormEvents::POST_SUBMIT,
function (FormEvent $event) use ($formModifier) {
$type = $event->getForm()->getData();
$start = $event->getForm()->getParent()->getData()->getStart();
$formModifier($event->getForm()->getParent(), $start, $type);
}
);
the problem here is that, for exemple when i try to add a listener to 'start' field inside of it, i don't have access to the other fields, the typeEvent field specifically, i tried $event->getForm()->getParent()->getData()->getTypeEvent() but it returns null, and that's $event->getForm()
dumped.
As you can see the $event->getForm()->getParent()->getData() it's like a new Event() with all attribute on null.
So my question is: There is any way to get the typeEvent there ? or should i proceed differently?
Thank you.

Answer 1

I am not completely sure if this is what you want, but you should take a look at this answer:
https://stackoverflow.com/a/25890150/17089665
$form->all(); <- Will get you all fields
$child->getName(); <- Will get you the name of every child, if you iterate the $form variable.