Boolean values and choice symfony type

Question

Using the choice type of Symfony framwork, we can decide de display lists, radio buttons or checkboxes playing with those two keys:

'multiple' => false,
'expanded' => true,  //example for radio buttons

Let's say that instead of strings the value of the different choices given as an array in the 'choices' key are booleans :

$builder->add('myproperty', 'choice', array(
    'choices' => array(
        'Yes' => true,
        'No' => false
     ),
     'label' => 'My Property',
     'required' => true,
     'empty_value' => false,
     'choices_as_values' => true
 )); 

Using a list (select) to display the differnet choices there is no problem and when the form is displayed the right choice in the list is selected.

If I add the two keys(multiple and expanded) I talked about before to replace the list by radio buttons, there is no selected button for my field (though it worked with the select).

Somebody knows why ?

How to easily make it work ?

Thank you

Note : in fact I thought it would not works with any of then as the values are booleans and finally become strings but as it works for the list, I wonder why it does not work for the others.

Answer 1

I add a data transformer;

$builder->add('myproperty', 'choice', array(
    'choices' => array(
        'Yes' => '1',
        'No' => '0'
     ),
     'label' => 'My Property',
     'required' => true,
     'empty_value' => false,
     'choices_as_values' => true
 )); 

 $builder->get('myProperty')
    ->addModelTransformer(new CallbackTransformer(
        function ($property) {
            return (string) $property;
        },
        function ($property) {
            return (bool) $property;
        }
  ));

It is magical : Now I have the right radio button checked and the right values in the entity.

Answer 2

Another solution is to use Doctrine Lifecycle Callbacks and php Type Casting.

With this FormType:

use Symfony\Component\Form\Extension\Core\Type\ChoiceType;

//...

$builder->add('active', ChoiceType::class, [
    'choices' => [
        'active' => true,
        'inactive' => false
    ]
])

And Entity like this :

//...
use Doctrine\ORM\Mapping as ORM;

/**
 * ...
 * @ORM\HasLifecycleCallbacks()                      /!\ Don't forget this!
 * ...
 */
class MyEntity {

    //..

    /**
     * @var bool
     *
     * @ORM\Column(name="active", type="boolean")
     */
    private $active;

    //...

    /**
     * @ORM\PrePersist()
     */
    public function prePersist()
    {
        $this->active = (bool) $this->active; //Force using boolean value of $this->active
    }

    /**
     * @ORM\PreUpdate()
     */
    public function preUpdate()
    {
        $this->active = (bool) $this->active;
    }    

    //...
}

Answer 3

My solution:

/**
 * @var BooleanToStringTransformer $transformer
*/
private $transformer;

/**
  * @param BooleanToStringTransformer $transformer
 */
public function __construct(BooleanToStringTransformer $transformer) {
   $this->transformer = $transformer;
}


public function buildForm(FormBuilderInterface $builder, array $options)
{
    $builder
        ->add('myProperty', TextType::class, [
            'empty_data' => false,
        ])
    ;

    $builder->get('myProperty')->addModelTransformer($this->transformer);
}

<?php

namespace App\DataTransformer;

use Symfony\Component\Form\DataTransformerInterface;

/**
 * Class BooleanToStringTransformer
 *
 * @package App\DataTransformer
 */
class BooleanToStringTransformer implements DataTransformerInterface
{
    /**
     * @param bool $boolean
     *
     * @return string
     */
    public function transform($boolean): string
    {
        // transform the boolean to a string
        return $boolean ? 'true' : 'false';
    }

    /**
     * @param string $string
     *
     * @return bool
     */
    public function reverseTransform($string): bool
    {
        // transform the string back to a boolean
        return filter_var($string, FILTER_VALIDATE_BOOL);
    }
}