gistfile1.txt

$this->add(array(
      'type' => 'Zend\Form\Element\Collection',
      'name' => 'properties',
      'options' => array(
        'label' => 'Please choose properties for this Asset',
        'count' => 2,
        'should_create_template' => true,
        'allow_add' => true,
        'target_element' => array(
          'type' => 'DoctrineORMModule\Form\Element\DoctrineEntity',
          'name' => 'property',
          'options' => array(
              'label' => 'Name of the Property',
              'object_manager' => $em,
              'target_class' => 'Asset\Entity\Property',
              'property' => 'name'
          ),
          'attributes' => array(
              'required' => 'required'
          )
    ));
        )
      )
    ));