How to set allow_empty on a form element using a factory in ZF2?

Question

Zend Framework

There is an element that has by default (allow_empty == true):

namespace Application\Form\Element\Text;

use Zend\Form\Element\Text;
use Zend\InputFilter\InputProviderInterface;
use Zend\Validator\NotEmpty;

class Login extends Text implements InputProviderInterface
{
    public function getInputSpecification()
    {
        return array(
            'name' => 'login',
            'required' => true,
            'allow_empty' => true,
            'validators' => array(
                array(
                    'name' => 'notEmpty',
                ),
            ),
        );
    }
}

When creating a form with this element using a factory, you need to set (allow_empty == false). The only way I've found requires you to know the name of the element, and that doesn't work:

$form = $factory->createForm(array(
    'elements' => array(
        array(
            'spec' => array(
                'type' => 'Application\Form\Element\Text\Login',
            ),
        ),
    ),
    'input_filter' => array(
        array(
            'name' => 'login',
            'allow_empty' => false,
        ),
    ),
));

For some reason, this method does not work as intended:

$form = $factory->createForm(array(
    'elements' => array(
        array(
            'spec' => array(
                'type' => 'Application\Form\Element\Text\Login',
                'allow_empty' => false,
            ),
        ),
    ),
));

Answer 1

The form element does not have the allow_empty property, it is the Input property (which is stored in the image and likeness of the form in the InputFilter), and is used there.