关于类型的symfony的动态形式

Question

I am trying to do a dynamic Form on two choiceList and i've tried to follow the documentation about SYmfony: http://symfony.com/doc/current/form/dynamic_form_modification.html#dynamic-generation-for-submitted-forms but the are using two entities and i have to work with choiceList Can anyone help me about that here is my UserTYpe:

$

builder
    ->add('at', ChoiceType::class, array(
        'label' => ' ',
        'choices' =>array(
            "42consulting.fr" => "42consulting.fr",
            "42consulting.lu" => "42consulting.lu",
            "42mediatvcom.fr" => "42mediatvcom.fr",
            "42consulting.ma" => "42consulting.ma",
            "42consulting.nl" => "42consulting.nl",
        ),
        'attr' => array(
            'class' => 'form-control',
            'placeholder' => 'service',
        ),
    )
);

$formModifier = function (FormInterface $form, User $at= null) {
    $services = null === $at ? array() :$at->getService();

    $form->add('service', ChoiceType::class, array(
                'label' => 'Service',
                'choices' => array(
                    "42Consulting Paris" => "Saint-Mandé",
                    "42Consulting Lux" => "Luxembourg",
                    "42MediaTelecom" => "Issy-Les-Moulineaux",
                    "42Consulting Maroc" => "Casablanca"
                ),
                'attr' => array(
                    'class' => 'form-control service',
                    'placeholder' => 'service',
                ),
            )
    );

};

$builder->addEventListener(
    FormEvents::PRE_SET_DATA,
    function (FormEvent $event) use ($formModifier) {
        $data = $event->getData();

        $formModifier($event->getForm(), $data->getAt());
    }
);

$builder->get('at')->addEventListener(
    FormEvents::POST_SUBMIT,
    function (FormEvent $event) use ($formModifier) {
        $at = $event->getForm()->getData();

        $formModifier($event->getForm()->getParent(), $at);
    }
);

and the error that i'm getting is : Type error: Argument 2 passed to BackBundle\Form\UserType::BackBundle\Form{closure}() must be an instance of BackBundle\Entity\User, string given, called in /home/work/Sites/backoffice-ad/src/BackBundle/Form/UserType.php on line 263 (on this line: $formModifier($event->getForm()->getParent(), $at);)

Answer 1

On the line

$formModifier = function (FormInterface $form, User $at= null) {

Your $at, as declare, this parameter must be an instance of User entity. But when you call this function, you passed a string:

$builder->addEventListener(
    FormEvents::PRE_SET_DATA,
    function (FormEvent $event) use ($formModifier) {
        $data = $event->getData();
        $formModifier($event->getForm(), $data->getAt());
    }
);

Have you tried:

$formModifier($event->getForm(), $data);

I'm not sure, but I think this is the problem when you call getAt(), this method return string. And $data variable is probably an instance of User entity.