Symfony Choice type with disabled options - forms

Question

Is there any way with Symfony to render a <select> form type with disabled options, based on the truthyness of the given choices options ?
I saw this thread (thanks to DonCallisto) about disabling choice expanded options ;
However I do not want to have an expanded choice.
I would like to keep a select element, with disabled options.
$builder->add('list', 'choice', array(
'choices' => array(
array(
'value' => 1,
'label' => '1',
'disabled' => false
),
array(
'value' => 2,
'label' => '2',
'disabled' => false
),
array(
'value' => 3,
'label' => '3',
'disabled' => true
)
),
// Instead of
// 'choices' => array(
// 1 => 'Option 1',
// 2 => 'Option 2',
// 3 => 'Option 3'
// )
);
# Which would render to the following element
<select [...]>
<option value='1'>1</value>
<option value='2'>2</value>
<option value='3' disabled='disabled'>3</value>
</select>
I just can't find the way...
Is it necessary to build its own field type ?

Answer 1

Since version 2.7, Symfony has introduced a way to set choice attributes using a callable, this is just what you need.
this code is taken from official Symfony documentation
$builder->add('attending', ChoiceType::class, array(
'choices' => array(
'Yes' => true,
'No' => false,
'Maybe' => null,
),
'choices_as_values' => true,
'choice_attr' => function($val, $key, $index) {
// adds a class like attending_yes, attending_no, etc
return ['class' => 'attending_'.strtolower($key)];
},
));
you can use the 'choice_attr' and pass a function that will decide wether to add a disabled attribute or not depending on the value, key or index of the choice.
...
'choice_attr' => function($key, $val, $index) {
$disabled = false;
// set disabled to true based on the value, key or index of the choice...
return $disabled ? ['disabled' => 'disabled'] : [];
},
...

Answer 2

According to the forms layout :
https://github.com/symfony/symfony/blob/2.7/src/Symfony/Bridge/Twig/Resources/views/Form/form_div_layout.html.twig
and the choice_widget_collapsed and choice_widget_options,i don't think it's possible directly with the default Choice form of Symfony.
You can try :
to build your own Choice form (by extending the existing one and adding parameters to option list, i think it's the best way)
to use javascript/jquery to modify the options parameters at load time with the existing Symfony's Choice from

Answer 3

This is another way to load options from Entity.
You can create a new Entity Attending and use it with EntityType.
->add('attending', EntityType::class, [
'class' => Attending::class,
'choice_attr' => function($key, $val, $index) {
if ($key->getId() == StaticVal) {
return ['disabled' => 'disabled'];
}
return [];
}]
Here StaticVal can be any value that you want to disable it.
$key will give you an object value
$val will give you a value starting from 0 if you are using the placeholder option.