Symfony2 form - how overwrite field with default value - php

Question

I have a form with one default value:
class GearType extends AbstractType
{
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder
->add('options')
->add('model', 'choice', array('choices' => $this->getModelChoices(), 'data' => 2));
}
one of the requirements is form can be pre-populated by re-sellers by passing parameters in URL. It is also nice feature for potential customers to copy and paste link to email, communicators, etc.
I did it this way:
/**
* #Route("/car/gear")
* #Template()
*/
public function gearAction(Request $request)
{
$form = $this->createForm(new GearType());
if ($request->isMethod('POST')) {
$form->bind($request);
if ($form->isValid()) {
return 'is valid';
}
} else {
$get = $this->getRequest()->query->all();
if (!empty($get)) {
$normalizer = new GetSetMethodNormalizer();
$form->setData($normalizer->denormalize($get, new Gear())); # look here
}
}
return array('form' => $form->createView());
}
unfortunately field 'options' has always default value, instead value passed as a parameter.
I have tried to change line # look here into
$gear = $normalizer->denormalize($get, new Gear());
$form = $this->createForm(new GearType(), $gear);
but no result.
It seems that solution is passing additional parameter to GearType object. I do not like this solution. Does anyone know better way?

Answer 1

Add this snippet, and modifiy between the [ ] as appropriate
$form->bind($request);
if ( [ passed parameters from querystring ] ){ //// New Code
$form->getData()->setOptions( [ processed parameter ]); //// New Code
} //// New Code
if ($form->isValid()) {
return 'is valid';
}

Answer 2

The reason for the field options always having default value may be the actual query. Instead of denormalizing and setting the data directly, modify else fragment to:
} else {
$form = $this->createForm(new GearType(), new Gear(), array(
'validation_groups' => array('not-validating')
));
$form->bind($request);
}
The form will validate only against validations associated with the not-validating group, which will avoid showing the common required alerts if the form is built form GET.
Docs about 'validations-groups': http://symfony.com/doc/current/book/forms.html#validation-groups
The question is similar to: Entity form field and validation in Symfony2?