i have a form definition which uses the so-far great field type entity. With the option query_builder I select my values and the are displayed.
The sad part is, I am required to display a null default value, like all (it's a filter form). I don't like the choices option of entity because I have database values and a FormType shouldn't query the database.
My approach so far was to implement a custom field type which extends entity and adds a null entry to the top of the list. The field type is loaded and used but unfortunately the dummy value is not displayed.
The field definition:
$builder->add('machine', 'first_null_entity', [
'label' => 'label.machine',
'class' => Machine::ident(),
'query_builder' => function (EntityRepository $repo)
{
return $repo->createQueryBuilder('m')
->where('m.mandator = :mandator')
->setParameter('mandator', $this->mandator)
->orderBy('m.name', 'ASC');
}
]);
The form type definition:
class FirstNullEntityType extends AbstractType
{
/**
* @var unknown
*/
private $doctrine;
public function __construct(ContainerInterface $container)
{
$this->doctrine = $container->get('doctrine');
}
public function setDefaultOptions(OptionsResolverInterface $resolver)
{
$resolver->setRequired('query_builder');
$resolver->setRequired('class');
}
public function buildView(FormView $view, FormInterface $form, array $options)
{
$class = $options['class'];
$repo = $this->doctrine->getRepository($class);
$builder = $options['query_builder']($repo);
$entities = $builder->getQuery()->execute();
// add dummy entry to start of array
if($entities) {
$dummy = new \stdClass();
$dummy->__toString = function() {
return '';
};
array_unshift($entities, $dummy);
}
$options['choices'] = $entities;
}
public function getName()
{
return 'first_null_entity';
}
public function getParent()
{
return 'entity';
}
}