Question

in symfony 1.4 it was possible to parameterize a form class definition, via the options of the form. Is there any way to pass custom options to my custom form type??? i’ve tried to use the options parameter of the buildForm method, but i’m not very sure what this array is, and apparently it is not for what i want… Thanks!

Answer 1

The solution is simple, if you want your custom option to be available also in Twig template, you must use
$builder->setAttribute() in buildForm method
and
$view->set() method in buildView() method, too.

<?php

namespace Acme\DemoBundle\Form\Type;

use Symfony\Component\Form\AbstractType as FormAbstractType;
use Symfony\Component\Form\FormBuilder;
use Symfony\Component\Form\FormView;
use Symfony\Component\Form\FormInterface;

// For Symfony 2.1 and higher:
use Symfony\Component\OptionsResolver\OptionsResolverInterface;

/**
 * ImagePreviewType
 *
 */
class ImagePreviewType extends FormAbstractType
{

    /**
     * {@inheritDoc}
     * For Symfony 2.0
     */
    //public function getDefaultOptions(array $options)
    //{
    //    $options = parent::getDefaultOptions($options);
    //    $options['base_path'] = 'path/to/default/dir/';
    //
    //    return $options;
    //}

    /**
     * {@inheritDoc}
     * For Symfony 2.1 and higher
     */
    public function setDefaultOptions(OptionsResolverInterface $resolver)
    {
        $resolver->setDefaults(array(
            'base_path'         => '',
        ));
    }

    /**
     * {@inheritDoc}
     */
    public function buildView(FormView $view, FormInterface $form, array $options)
    {
        // For Symfony 2.0:
        // $view->set('base_path', $form->getAttribute('base_path'));

        // For Symfony 2.1 and higher:
        $view->vars['base_path'] = $options['base_path'];
    }

    /**
     * {@inheritDoc}
     */
    public function buildForm(FormBuilder $builder, array $options)
    {
        $builder
            ->setAttribute('base_path', $options['base_path'])
        ;
    }

    /**
     * {@inheritDoc}
     */
    public function getName()
    {
        return 'image_preview';
    }

    public function getParent(array $options)
    {
        // for Symfony 2.0:
        // return 'field';

        // for Symfony 2.1 and higher:
        return 'form';
    }
}

Template for custom form type (file …Acme/DemoBundle/Resources/views/Form/fields.html.twig):

{% block image_preview_widget %}
{% spaceless %}
<img src="{{ base_path ~ value }}" alt=""  {{ block('widget_container_attributes') }} />
{% endspaceless %}
{% endblock %}

Register your template for custom form types in app/config/config.yml

twig:
    debug:            %kernel.debug%
    strict_variables: %kernel.debug%
    form:
        resources:
            - 'AcmeDemoAdminBundle:Form:fields.html.twig'

Usage: Display preview of user’s image while editing his profile:

// src/Acme/DemoBundle/Form/Type/UserType.php
namespace Acme\DemoBundle\Form\Type;

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilder;

class UserType extends AbstractType
{
    public function buildForm(FormBuilder $builder, array $options)
    {
        $builder->add('user_profile_image_file_name', new ImagePreviewType(), array(
            'base_path' => 'some/other/dir',
        ));
    }
}

2014-08-18: Updated for Symfony 2.1 or higher