Declaring Symfony Form options (Sym 2.8/3.0) - symfony-forms

Question

I am looking for the best method for creating/adding dynamic options in a form. By options, I mean things like choice value pairs, or maybe even default values. I can see at least three options:
1) add the options to the $options array when adding the form type. For this, it appears that I must first declare a default value and then add them in the add method and in the controller:
controller:
$choices = [];
foreach ($pages as $page) {
$choices[$page->getId()] = $page->getTitle();
}
$options = ['pages' => $choices];
$form = $this->createForm('MyBundle\Form\Type\PageType', $data, $options);
FormType:
class PageType extends AbstractType
{
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder
->add('pid', 'Symfony\Component\Form\Extension\Core\Type\ChoiceType', [
'choices' => $options['pages'],
'label' => __('Page')
]);
}
...
public function configureOptions(OptionsResolver $resolver)
{
$resolver->setDefaults([
'pages' => []
]);
}
}
2) If the values are not dependent on controller values, it seems I could create them in the OptionsResolver (assuming access to the source data)
FormType:
class PageType extends AbstractType
{
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder
->add('pid', 'Symfony\Component\Form\Extension\Core\Type\ChoiceType', [
'choices' => $options['pages'],
'label' => __('Page')
]);
}
...
public function configureOptions(OptionsResolver $resolver)
{
$choices = [];
$pages = $this->getPages();
foreach ($pages as $page) {
$choices[$page->getId()] = $page->getTitle();
}
$resolver->setDefaults([
'pages' => $choices
]);
}
3) Finally, I can also add in the buildForm method (again assuming access to source data):
FormType:
public function buildForm(FormBuilderInterface $builder, array $options)
{
$choices = [];
$pages = $this->getPages();
foreach ($pages as $page) {
$choices[$page->getId()] = $page->getTitle();
}
$builder
->add('pid', 'Symfony\Component\Form\Extension\Core\Type\ChoiceType', [
'choices' => $choices,
'label' => __('Page')
]);
}
Obviously, there is the most flexibility in the first option, but If I do not require that flexibility, or do not want to manage the options in the controller for some reason, does it make more sense to do the work in the buildForm or configureOptions methods?

Answer 1

If you require flexibility you can't use solution 3. But if you want to avoid flexibility, solution 3 is the best.
Solution 1 and 2 are OK, it really depend of what you need :
If you use your form in several actions with different choices: use solution 1, but add a requirement on this option to prevent the form to be called without choices
If your choices are often the same, but you want to override them only sometimes: chose solution 2
Personally I prefer the solution 1, because it's always better if your form relies on the less possible external objects ($this->pages in your example).
Regards

Answer 2

If you work with Doctrine Entities, you should use this:
use Symfony\Bridge\Doctrine\Form\Type\EntityType;
// ...
$builder->add('pid', EntityType::class, array(
'class' => 'AppBundle:Page',
'choice_label' => 'title',
));
For working with another type of objects this one:
use Symfony\Component\Form\Extension\Core\Type\ChoiceType;
use AppBundle\Entity\Page;
// ...
$builder->add('pid', ChoiceType::class, [
'choices' => [
new Page('Page 1'),
new Page('Page 2'),
new Page('Page 3'),
new Page('Page 4'),
],
'choices_as_values' => true,
'choice_label' => function($page, $key, $index) {
/** #var Page $page */
return $page->getTitle();
}
]);
More information you can read in blog post here.