symfony2 creating custom field type

Question

Hi Im trying to create custom field like here but after adding to service.yml

services:
    griffin.type.datetime_to_string:
        class: griffin\CoreBundle\Form\DateTimeType
        arguments: ["@doctrine.orm.entity_manager"]
        tags:
            - { name: form.type, alias: datetime_to_string }

Im getting Catchable Fatal Error: Argument 1 passed to griffin\\CoreBundle\\Form\\DataTransformer\\DateTimeToStringTransformer::__construct() must implement interface Doctrine\\Common\\Persistence\\ObjectManager, null given any one had this problem ?

EDIT

namespace griffin\CoreBundle\Form;

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;
use griffin\CoreBundle\Form\DataTransformer\DateTimeToStringTransformer;
use Doctrine\Common\Persistence\ObjectManager;
use Symfony\Component\OptionsResolver\OptionsResolverInterface;
/**
 * Description of DateTimeType
 *
 * @author skowron-line
 */
class DateTimeType extends AbstractType {

    private $om;

    public function __construnct(ObjectManager $om) {
        $this->om = $om;
    }

    public function buildForm(FormBuilderInterface $builder, array $options) {
        var_dump($this->om);
        $transformer = new DateTimeToStringTransformer($this->om);
        $builder->addModelTransformer($transformer);
    }

    public function setDefaultOptions(OptionsResolverInterface $resolver) {
        $resolver->setDefaults(array(
            'invalid_message' => 'err',
        ));
    }

    public function getParent() {
        return 'text';
    }

    public function getName() {
        return 'datetime_to_string';
    }
}

and in my controller

$form = $this->createForm(new KlientType(), $klient);

Answer 1

If you want to use a custom FormType as a service ( because you need to have services or parameters injected ) you must add the field to your builder with it's service name (or alias) and not with new CustomFormType().

$builder->add('date', 'datetime_to_string', array(
    // ...
))

DateTime to string conversion is already provided by Symfony since 2.0.

Have a look at Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToStringTransformer

You can transform the date field into a text input with the "widget" option set to "single_text" and the format option set to your desired text-representation.

$builder->add('publishedAt', 'date', array(
    'widget' => 'single_text',
    'format' => 'yyyy-MM-dd',
));

Transformed into a text input this field can easily be integrated with common JavaScript Datepickers. Consider using that one instead of your own implementation.

Tip:

You don't have to surround the injected service with " in yml.

services:
    griffin.type.datetime_to_string:
        class: griffin\CoreBundle\Form\DateTimeType
        arguments: [@doctrine.orm.entity_manager]
        tags:
            - { name: form.type, alias: datetime_to_string }

This often leads to errors when copy/pasting from tutorials on the net where symbols are auto-converted into something different than "real" question marks.