ChoiceList as service possible? - forms

Question

I have the following code:
namespace Acme\Demo\Form;
use Symfony\Component\Form\Extension\Core\ChoiceList\LazyChoiceList;
use Symfony\Component\Form\Extension\Core\ChoiceList\SimpleChoiceList;
class MyChoiceList extends LazyChoiceList
{
protected function loadChoiceList()
{
return SimpleChoiceList(array('t'=>'test'));
}
}
services.yml:
SMyChoiceList:
class: Acme\Demo\Form\MyChoiceList;
Then when I try to do:
$builder
->add('mychoice', 'choice', array('choice_list' => 'SMyChoiceList'
));
I get:
The option "choice_list" with value "SMyChoiceList" is expected to be of type "null", "Symfony\Component\Form\Extension\Core\ChoiceList\ChoiceListInterface"
LazyChoiceList already implements ChoiceListInterface... so I'm guessing Symfony2 choice_list parameter doesn't support services or am I missing something?
I assumed it worked similar to http://symfony.com/doc/current/cookbook/form/create_custom_field_type.html#form-cookbook-form-field-service
But I guess not.

Answer 1

With ..
'choice_list' => 'SMyChoiceList'
.. you are just using a string.
You can call it directly using ..
'choice_list' => new MyChoiceList()
Or if it has dependents you can inject it into your form constructor like..
your.form:
class: %your.form.class%
arguments:
- #SMyChoiceList
tags:
- { name: form.type, alias: your_form_alias }
.. and then use it in your form like..
protected $choiceList;
public function __construct(ChoiceListInterface $choiceList)
{
$this->choiceList = $choiceList;
}
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder
->add('mychoice', 'choice', array(
'choice_list' => $this->choiceList,
))
;
}
UPDATE
To use your choice list in a custom form type you would do the following (using the same services set up as above)...
protected $choiceList;
public function __construct(ChoiceListInterface $choiceList)
{
$this->choiceList = $choiceList;
}
public function setDefaultOptions(OptionsResolverInterface $resolver)
{
$resolver->setDefaults(array(
'choice_list' => $this->choiceList,
));
}
public function getParent()
{
return 'choice';
}
public function getName()
{
return 'your_form_alias';
}
Which you could then use instead of choice, like...
$builder
->add('something', 'your_form_alias', array(
// Your choice options (expanded, label, attr, etc)
))
;
It's all in the page that you added before, more specifically http://symfony.com/doc/current/cookbook/form/create_custom_field_type.html#defining-the-field-type