Symfony2 Forms - How to populate a related Entity's field automatically? - php

Question

I am trying to follow the symfony2 dynamic form modification tutorial at http://symfony.com/doc/current/cookbook/form/dynamic_form_modification.html#cookbook-form-events-submitted-data
My schema is a bit different to the one which they use in their tutorial. Mine consists of the following relationships:
Country (one to many) Office
Office (one to many) Employee
When I edit an existing employee, I would like it to load the Country where the Office is located as the default option, in addition to only showing the offices within that country in the Office dropdown (unless another country is selected, then the jQuery code (not included) should change that accordingly).
The result, however; is that the Country field still shows the placeholder value instead of the correct country for the Employee's Office. (On the plus side, the Office dropdown only shows the offices for that country, which means the $country->getOffices() call is working so I am working with the correct Country object, I just can't seem to have it selected by default).
Am I following the best practice here? Is there something I'm missing which isn't letting me set values in the form for related Entities?
Code:
class EmployeeType extends AbstractType
{
/**
* #param FormBuilderInterface $builder
* #param array $options
*/
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder
->add('name')
->add('country', EntityType::class, array(
'class' => 'AppBundle:Country',
'mapped' => false,
'placeholder' => '=== Select a Country ===',
))
;
$builder->addEventListener(
FormEvents::PRE_SET_DATA,
function (FormEvent $event) {
$form = $event->getForm();
// This will be the Employee entity
$data = $event->getData();
$office = $data->getOffice();
$country = null === $office ? array() : $office->getCountry();
$form->get('country')->setData($country); // I think this is what's not working properly.
$form->add('office', EntityType::class, array(
'class' => 'AppBundle:Office',
'placeholder' => '=== Select an Office ===',
'choices' => $country->getOffices(),
));
}
);
}

Answer 1

I had a chance to quickly read the tutorial link you reference, and I think you are right as to where the error is occurring.
I think (but I'm not sure), that this might the fix:
$office = $data->getOffice();
$offices = null === $office ? array() : $office->getCountry()->getOffices();
$form->add('office', EntityType::class, array(
'class' => 'AppBundle:Office',
'placeholder' => '=== Select an Office ===',
'choices' => $offices,
));
I only show the relevant sections which you need to change. Try it out and see if that helps.

Answer 2

Try to modify the data on the event instead:
class EmployeeType extends AbstractType
{
/**
* #param FormBuilderInterface $builder
* #param array $options
*/
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder
->add('name')
->add('country', EntityType::class, array(
'class' => 'AppBundle:Country',
'mapped' => false,
'placeholder' => '=== Select a Country ===',
))
;
$builder->addEventListener(
FormEvents::PRE_SET_DATA,
function (FormEvent $event) {
$form = $event->getForm();
// This will be the Employee entity
$data = $event->getData();
$office = $data->getOffice();
// since the country field is not set as "multiple"
// the data should not be an array but a string
$country = null === $office ? '' : $office->getCountry();
$data['country'] = $country(->getName()?);
$event->setData($data); // may work
$form->add('office', EntityType::class, array(
'class' => 'AppBundle:Office',
'placeholder' => '=== Select an Office ===',
'choices' => $country->getOffices(),
));
}
);
}
}