Add a required form field based on submitted data in Symfony2 - php

Question

I have a form with a status select. If a certain status is selected and the form is submitted it should reload and require an additional field.
I have read Dynamic generation for submitted Forms and almost every other post on the internet and about this topic and tried different event combinations (and got different errors) but I still struggle to make this to work correctly.
This is what I have so far:
FormType
private function addProcessAfterField(FormInterface $form)
{
$form->add('processAfterDate', 'date', array('required' => true));
}
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder->add('status', 'entity', array(
'class' => 'Acme\Bundle\ApplicationBundle\Entity\LeadStatusCode',
'choices' => $this->allowedTypes
));
$builder->addEventListener(FormEvents::PRE_SET_DATA, function(FormEvent $event){
$form = $event->getForm();
$data = $event->getData();
if ($data->getStatus()->getId() == LeadStatusCode::INTERESTED_LATER) {
$this->addProcessAfterField($form);
}
});
$builder->get('status')->addEventListener(FormEvents::POST_SUBMIT, function(FormEvent $event){
$data = $event->getData();
if ($data == LeadStatusCode::INTERESTED_LATER && !$event->getForm()->getParent()->getData()->getProcessAfterDate()) {
$this->addProcessAfterField($event->getForm()->getParent());
}
});
$builder->add('comment', 'textarea', array('mapped' => false));
$builder->add('Update', 'submit');
}
Error:
ContextErrorException: Catchable Fatal Error: Argument 1 passed to Proxies\__CG__\Acme\Bundle\ApplicationBundle\Entity\Lead::setProcessAfterDate() must be an instance of DateTime, null given, called in /var/www/application.dev/vendor/symfony/symfony/src/Symfony/Component/PropertyAccess/PropertyAccessor.php on line 360 and defined in /var/www/application.dev/app/cache/dev/doctrine/orm/Proxies/__CG__AcmeBundleApplicationBundleEntityLead.php line 447
As already mentioned I tried different event combinations, one was almost working but then the date was never persisted to the entity so I added the \DateTime type-hint to the setProcessAfterDate() method. I am not sure if I don`t understand the event system correctly or if the error lies somewhere else.

Answer 1

Well, it might not be the best way to solve it, but to make long story short:
$form->handleRequest($request);
if($form->isValid()) // check if the basic version of the form is ok
{
$form = $this->createForm(new XXXXForm(), $form->getData()); // you recreate the form with the data that was submitted, so you rebuild the form with new data
if($form->isValid())
{
// ok
}
// not ok
}
Then inside buildForm function, you base the "required" attribute value of fields based on what you want:
'required' => $this->getCheckRequired($options)
private function getCheckRequired($options) // checks whether field should be required based on data bound to the form
{
if($options && isset($options['data'])
{
switch $options['data']->getStatus():
// whatever
;
}
return false;
}
As I said, this is not the best solution, and it doesn't fix your approach, but rather proposes a different one, but it does the job