ZF2 Dependent Form Fields - forms

Question

How can i set a input filter which is dependent from another input field.
I want to set a form field as required only when the othe form field (checkbox) is selected.
How can i handle this in zf2 ?

Answer 1

I use the same idea as Crisp but I prefer to do it in the Form classes instead of the controller. I think it's better to have all validators defined all together in the same place. I do it this way:
1 - All Form classes inherits from a custom BaseForm:
class BaseForm extends ProvidesEventsForm
{
private $postData;
protected function getPostData() {
return $this->postData;
}
public function __construct( $name = null, $serviceManager ) {
parent::__construct( $name );
$this->serviceManager = $serviceManager;
$this->request = $serviceManager->get( 'Application' )->getMvcEvent()->getRequest();
$this->postData = get_object_vars( $this->request->getPost() );
}
}
This way you can easily pick any value from the post, like your checkbox (you can do the same approach with the route parameters, so you'll have all the view data in your Form).
2 - In the FormEdit class that inherits from BaseForm, you pass the getPostData() value to the SomeFilter this way:
class FormEdit extends BaseForm
{
public function __construct( $name = null, $serviceManager ) {
parent::__construct( $name, $serviceManager );
$filter = new SomeFilter( $this->getPostData() );
$this->setInputFilter( $filter );
}
3 - And now just use it in the SomeFilter:
class SomeFilter extends InputFilter
{
public function __construct( $postData ) {
if ( $postData[ 'checkbox' ] ) {
$this->add( array(
'name' => 'other_input',
'required' => true,
) );
}
}
}
This way you keep the Controller clean and all the validators in the same place.

Answer 2

You could test if the checkbox is populated and setValidationGroup accordingly on the form before validating it in your controller action...
public function someAction()
{
$form = new MyForm; // contains name, title, checkbox, required_if_checked fields
// usual form related setup
if ($request->isPost()) {
$form->setData($request->getPost());
// see if the checkbox is checked
$checked = $this->params()->fromPost('checkbox', false);
// not checked, set validation group, omitting the dependent field
if (!$checked) {
$form->setValidationGroup(array(
'name',
'title',
'checkbox', // could probably skip this too
));
}
if ($form->isValid()) {
// do stuff with valid data
}
}
}