Question

Is there any good solution for the following requirements:

• A form with one field for zip code and default validators like number, length, etc.
• After submission, the form is checked against a database.
• If the zip code is not unique we have to ask for an city.

Examples:

Case 1: Submited zip code is unique in database. Everything is okay. Process form

Case 2: Submited zip code is not unique. Add a second field for city to the form. Go back to form.

We want to handle this in an generic way (not inside an controller). We need this logic for
a lot of forms. First thought was to add it to isValid() to every form or write a
validator with logic to add fields to the form. Subforms are not possible for us, because we need this for different fields (e.g. name and street).

Answer 1

Currently I’m using isValid method inside my forms for an User Form to verify the password and confirm password field. Also, when the form is displayed in a New Action, there are no modifications, but when displayed in an Edit Action, a new field is added to the form.

I think that is a good option work on the isValid method and add the field when the validation return false, and if you want something more maintainable, you should write your own validatator for that purpose.

Take a look at my code:

class Admin_Form_User extends Zf_Form 
{
    public function __construct($options = NULL)
    {
        parent::__construct($options);
        $this->setName('user');

        $id = new Zend_Form_Element_Hidden('id');

        $user = new Zend_Form_Element_Text('user');
        $user->setLabel('User:')
        ->addFilter('stripTags')
        ->addFilter('StringTrim')
        ->setAllowEmpty(false)
        ->setRequired(true);

        $passwordChange = new Zend_Form_Element_Radio('changePassword');
        $passwordChange->setLabel('Would you like to change the password?')
        ->addMultiOptions(array(1 => 'Sim', 2 => 'Não'))
        ->setValue(2)
        ->setSeparator('');

        $password = new Zend_Form_Element_Password('password');
        $password->setLabel('Password:')
        ->addFilter('stripTags')
        ->addFilter('StringTrim')
        ->setRequired(true);

        $confirm_password = new Zend_Form_Element_Password('confirm_password');
        $confirm_password->setLabel('Confirm the password:')
        ->addFilter('stripTags')
        ->addFilter('StringTrim')
        ->addValidator('Identical')
        ->setRequired(true);

        $submit = new Zend_Form_Element_Submit('submit');
        $submit->setLabel('Save');

        $this->addElements(array($id,$name,$lastname,$group,$user,$passwordChange,$password,$confirm_password,$submit));

        $this->addDisplayGroup(array('password','confirm_password'),'passwordGroup');
        $this->submit->setOrder(8);

        $this->setDisplayGroupDecorators(array(
            'FormElements',
            array('HtmlTag', array('tag' => 'div','id' => 'div-password'))
            )
        );

        $passwordChange->clearDecorators();

    }

    public function addPasswordOption()
    {
        $this->changePassword->loadDefaultDecorators();

        $this->getDisplayGroup('passwordGroup')
        ->addDecorators(array(
            array('HtmlTag', array('tag' => 'div','id' => 'div-password'))
            )
        );

        $this->password->setRequired(false);
        $this->confirm_password->setRequired(false);
    }

    public function setPasswordRequired($flag = true)
    {
        $this->password->setRequired($flag);
        $this->confirm_password->setRequired($flag);
    }

    public function isValid($data)
    {
        $confirm = $this->getElement('confirm_password');
        $confirm->getValidator('Identical')->setToken($data['password']);
        return parent::isValid($data);
    }

}

So, in my controller:

public function newAction()
    {
        $this->view->title = "New user";
        $this->view->headTitle($this->view->title, 'PREPEND');

        $form = $this->getForm();

        if($this->getRequest()->isPost()) 
        {
            $formData = $this->_request->getPost();

            if($form->isValid($formData))
            {
                $Model = $this->getModel();
                $id = $Model->insert($formData);

                $this->_helper->flashMessenger('The user data has beed updated.');
                $this->_helper->redirector('list');
            }
        }

        $this->view->form = $form;
    }

    public function editAction()
    {       
        $this->view->title = "Edit user";
        $this->view->headTitle($this->view->title, 'PREPEND');

        $id = $this->getRequest()->getParam('id');

        $form = $this->getForm();

        // Add yes or no password change option
        $form->addPasswordOption();

        $Model = $this->getModel();

        if($this->getRequest()->isPost()) 
        {
            $formData = $this->getRequest()->getPost();

            // Change password?
            if($formData['changePassword'] == 2) $form->setPasswordRequired(false);

            if($form->isValid($formData)) 
            {
                $Model->update($formData);

                $this->_helper->flashMessenger('The user data has beed updated.');
                $this->_helper->redirector('list');
            } 

        }

        $data = $Model->getById($id)->toArray();

        $form->populate($data);

        $this->view->form = $form;
    }