Forms With Checkboxes For Each Entity in Symfony

Goal

To display a list of records, select the records with checkboxes, then apply a batch update to the records when the form is submitted.

Form class

// src/AppBundle/Form/Type/PendingTutorialOptionType.php

// ...

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;
use Symfony\Component\OptionsResolver\OptionsResolverInterface;

class PendingTutorialOptionType extends AbstractType
{
	public function buildForm(FormBuilderInterface $builder, array $options)
	{
		$builder->add('tutorialId', 'entity', array(
			'required' => false,
			'class' => 'AppBundle:TutorialTemp',
			'property' => 'id',
			'property_path' => '[id]',
			'multiple' => true,
			'expanded' => true
		));
		$builder->add('update', 'submit', array('label' => 'save selected'));
    }

    public function setDefaultOptions(OptionsResolverInterface $resolver)
    {
        $resolver->setDefaults(array(
            'data_class' => null
        ));
    }

    public function getName()
    {
        return 'pending_tutorials';
    }
}

• In the buildForm() routine,
  • Use entity as the field type.
  • Assign the entity type with the class option.
  • The property and property_path options assign the id field of the entity to the checkbox elements.
  • multiple and expanded options set to true cause the form to render with a series of checkboxes as opposed to text fields (or dropdowns if the field type was choice).
• Important to set data_class to null in setDefaultOptions().
• Value returned by getName() is used to identify the form in the Twig template and to collect the form data after it is submitted.

Controller

// src\AppBundle\Controller\DefaultController.php

//...
	public function pendingAction(Request $request)
	{
		// get all the available options
		$pending_options = $this->get('app.pending_tutorial_options')
			->getTutorialOptionsList();

		// get a form object, passing it the available options
		$form = $this->createForm(new PendingTutorialOptionType(), $pending_options);

		// process form submission
		$form->handleRequest($request);

		// check if form data was submitted
		if ($form->isValid()) {
			
			// collect selected entities from form data
			$data = $form['tutorialId']->getData();

			$selected_ids = array();
			foreach($data as $tutorial) {
				// $data is a collection of PendingTutorial objects with all their data
				array_push($selected_ids, $tutorial->getId();
			}

			// do something with the matching records...
// ...

$form->getData() returns a collection of all the available options in the form. $form['tutorialId']->getData() returns the selected options as entity objects.

There is a

N.B. I was having difficulty with isValid() because I was manually inserting the submit buttons in the form, with a name value of form[update]. The form class returns pending_options as its name; the correct value for the submit button's name should have been pending_options[update].

Template

{{ form_start(form) }}
{{ form_errors(form) }}
<button type="submit" class="btn btn-default" name="form[update]">save selected</button>
{% for tutorial in tutorials %}
{{ form_widget(form.tutorialId[loop.index0] ) }}
{% endfor %}
<button type="submit" class="btn btn-default" name="form[update]">save selected</button>
{% do form.update.setRendered %}{# compensates for manually inserting this multiple times in the form #}
{{ form_end(form) }}

1. The checkboxes are rendered with form_widget().
   1. tutorialId corresponds to the index of the checkbox collection added to the form builder object.
   2. The individual checkboxes in the collection are accessed through a numeric index. Twig provides the loop.index0 helper.
2. The html for the submit buttons are is manually inserted into the template. The Symfony helper functions will only render a form element once to avoid duplicate id values.
3. form_end() will render any fields that have not explicitly rendered in the form already. form.update.setRendered prevents this.

Processing the form data

After the call to $form->getData(), the submitted form data will be accessible through an array:

array (size=1)
  'tutorialID' => 
    array (size=3)
      0 => int 3
      1 => int 6
      2 => int 9

Examples

• Pending Tutorials, Tutorial Database