How to create symfony form in standalone case using form component?

Question

symfony

Есть класс формы

class SignInForm extends AbstractType
{
    public function 
buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder
            ->add('login')
            ->add('password')
            ->add('save', 'submit');
    }

    public function getName()
    {
        return 'signin';
    }
}

как его привязать к entity и отправить на рендер?

что-то вроде 
 $form = $formFactory->create(new SignupForm(), $user);
 $view->form = $form->createView();

P/S I'm interested in creating the form directly in the class not via $formFactory->createBuilder()->getForm()

Answer 1

Everything about forms is written in the documentation: symfony.com/doc/current/book/forms.html#book-form-...
In the controller, create a form right away:

$form = $this->createForm(new SignInForm(), null, array(
    'action' => $this->generateUrl('login_check'),
    'method' => 'POST',
));

As far as I understood, your form doesn't need to pass the $user object. If you still need, then specify it instead of null.
Form parameters (action and method) should also be specified in the form class. Then it will be even easier:
$form = $this->createForm(new SignInForm());