Encargo Vigencia Form

<?php
namespace Cadastro\Form;

use Zend\Form\Form;
use Zend\InputFilter\InputFilterProviderInterface;
use Zend\Form\Element\Submit;
use Zend\Form\Element\Text;
use Application\Hydrator\ObjectHydrator;

/**
 * Cadastro de custas
 *
 * @author Alfredo Costa
 * @category Form
 * @package Cadastro/Form
 * @copyright 2014 P21 Sistemas
 * @version 1.0.0
 */
class EncargoVigenciaForm extends Form implements InputFilterProviderInterface
{

    /**
     */
    public function __construct($objectManager)
    {
        parent::__construct('custas');

        $this->setHydrator(new ObjectHydrator($objectManager))->setObject(new \Cadastro\Entity\EncargoVigencia());

        $this->add(array(
            'type' => 'Zend\Form\Element\Hidden',
            'name' => 'id'
        ));

        // COMBO
        $this->add(array(
            'type' => 'DoctrineModule\Form\Element\ObjectSelect',
            'name' => 'encargo',
            'options' => array(
                'label' => 'Encargo',
                'object_manager' => $objectManager,
                'target_class' => 'Cadastro\Entity\Encargo',
                'display_empty_item' => true,
                'label_generator' => function ($encargo)
                {
                    return $encargo->getNome();
                },
                'is_method' => true,
                'find_method' => array(
                    'name' => 'findBy',
                    'params' => array(
                        'criteria' => array(),
                        'orderBy' => array(
                            'nome' => 'ASC'
                        )
                    )
                )
            ),
            'attributes' => array(
                'class' => 'form-control',
                'id' => 'encargo'
            )
        ));

        $this->add(array(
            'type' => 'Zend\Form\Element\Collection',
            'name' => 'valores',
            'options' => array(
                 'label' => 'Valores',
                'count' => 1,
                'target_element' => new EncargoValorFieldset($objectManager)
            )
        ));

        $this->add(array(
            'type' => 'Zend\Form\Element\Date',
            'name' => 'dataVigencia',
            'options' => array(
                'label' => 'Data vigência',
                'format' => 'd/m/Y'
            ),
            'attributes' => array(
                'class' => 'form-control form-control-inline input-medium date-picker'
            )
        ));

        $this->add(array(
            'type' => 'Zend\Form\Element\Submit',
            'name' => 'confirmar',
            'attributes' => array(
                'class' => 'btn blue',
                'value' => 'Confirmar'
            )
        ));

        $this->add(array(
            'type' => 'Zend\Form\Element\Submit',
            'name' => 'cancelar',
            'attributes' => array(
                'class' => 'btn default',
                'value' => 'Cancelar'
            )
        ));
    }

    public function getInputFilterSpecification()
    {
        return array();
    }
}