Symfony Advent Calendar 2025 の17日目の記事です🎄

タイトルの通り、Symfony7.4からAbstractFlowTypeを使って簡単にマルチステップフォームを作成できるようになったようなので、使ってみました🤶
その方法と感想をまとめます！

参考記事はこちら👇
https://symfony.com/blog/new-in-symfony-7-4-multi-step-forms

動作環境

PHP 8.2.25
Symfony 7.4.2

実装してみる！

$ symfony new multi-step-form --version=7.4 webapp

Symfony7.4からAbstractFlowTypが使用可能となっています。

DTO

<?php
declare(strict_types=1);

namespace App\Form\Data;

use Symfony\Component\Validator\Constraints as Assert;

class MultiStepDto
{
    // Step 1:
    #[Assert\NotBlank(groups: ['step1'])]
    public ?string $username = null;

    #[Assert\NotBlank(groups: ['step1'])]
    #[Assert\Length(min: 3, groups: ['step1'])]
    #[Assert\Email(groups: ['step1'])]
    public ?string $email = null;

    // Step 2:
    #[Assert\NotBlank(groups: ['step2'])]
    public ?int $age = null;

    #[Assert\NotBlank(groups: ['step2'])]
    public ?string $pref = null;

    // Step 3:
    #[Assert\NotBlank(groups: ['step3'])]
    #[Assert\Length(min: 3, groups: ['step3'])]
    public ?string $freeText = null;

    #[Assert\IsTrue(groups: ['step3'])]
    public ?bool $cookieUse = false;

    // Current step value:
    public ?string $currentStep = null;
}

FormType

<?php
declare(strict_types=1);

namespace App\Form\Type;

use App\Form\Data\MultiStepDto;
use App\Form\Type\Step\Step1Type;
use App\Form\Type\Step\Step2Type;
use App\Form\Type\Step\Step3Type;
use Symfony\Component\Form\Flow\AbstractFlowType;
use Symfony\Component\Form\Flow\FormFlowBuilderInterface;
use Symfony\Component\Form\Flow\Type\NavigatorFlowType;
use Symfony\Component\Form\Flow\Type\NextFlowType;
use Symfony\Component\Form\Flow\Type\PreviousFlowType;
use Symfony\Component\OptionsResolver\OptionsResolver;

class MultiStepType extends AbstractFlowType
{
    public function buildFormFlow(FormFlowBuilderInterface $builder, array $options): void
    {
        $builder->addStep('step1', Step1Type::class);
        $builder->addStep('step2', Step2Type::class);
        $builder->addStep('step3', Step3Type::class);

        $builder->add('navigator', OriginalNavigatorFlowType::class);
        
        // ボタン等がデフォルトのままで良い場合は以下でok
        // $builder->add('navigator', NavigatorFlowType::class);
    }

    public function configureOptions(OptionsResolver $resolver): void
    {
        $resolver->setDefaults([
            'data_class' => MultiStepDto::class,
            'step_property_path' => 'currentStep',
            'translation_domain' => false,
        ]);
    }
}

（Step2Type, Step3Typeは省略してます）

<?php
declare(strict_types=1);

namespace App\Form\Type\Step;

use App\Form\Data\MultiStepDto;
use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\Extension\Core\Type\TextareaType;
use Symfony\Component\Form\FormBuilderInterface;
use Symfony\Component\OptionsResolver\OptionsResolver;

class Step1Type extends AbstractType
{
    public function buildForm(FormBuilderInterface $builder, array $options): void
    {
        $builder
            ->add('username')
            ->add('email')
        ;
    }

    public function configureOptions(OptionsResolver $resolver): void
    {
        $resolver->setDefaults([
            'data_class' => MultiStepDto::class,
            'inherit_data' => true,
            'label' => 'step1',
        ]);
    }
}

ボタンのテキストを変更したり、装飾する場合はこんな感じ。

<?php

declare(strict_types=1);

namespace App\Form\Type;

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\Flow\FormFlowCursor;
use Symfony\Component\Form\Flow\Type\FinishFlowType;
use Symfony\Component\Form\Flow\Type\NextFlowType;
use Symfony\Component\Form\Flow\Type\PreviousFlowType;
use Symfony\Component\Form\FormBuilderInterface;
use Symfony\Component\OptionsResolver\OptionsResolver;

class OriginalNavigatorFlowType extends AbstractType
{
    public function buildForm(FormBuilderInterface $builder, array $options): void
    {
        $builder
            ->add('back', PreviousFlowType::class, [
                'label' => 'Back',
                'attr' => ['class' => 'btn btn-secondary'],
            ])
            ->add('next', NextFlowType::class, [
                'label' => 'Next',
                'include_if' => fn (FormFlowCursor $cursor): bool => $cursor->getCurrentStep() !== 'documents' && $cursor->canMoveNext(),
                'attr' => ['class' => 'btn btn-primary'],
            ])
            ->add('finish', FinishFlowType::class, [
                'label' => 'Submit',
                'attr' => ['class' => 'btn btn-success'],
            ]);
    }

    public function configureOptions(OptionsResolver $resolver): void
    {
        $resolver->setDefaults([
            'label' => false,
            'mapped' => false,
            'priority' => -100,
        ]);
    }
}

Controller

<?php
declare(strict_types=1);

namespace App\Controller;

use App\Form\Data\MultiStepDto;
use App\Form\Type\MultiStepType;
use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
use Symfony\Component\Form\Flow\FormFlowInterface;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\Routing\Attribute\Route;

class MultiStepFormController extends AbstractController
{
    #[Route('/form', name: 'app_form')]
    public function __invoke(Request $request): Response
    {
        /** @var FormFlowInterface $flow */
        $flow = $this->createForm(MultiStepType::class, new MultiStepDto())
            ->handleRequest($request);

        if ($flow->isSubmitted() && $flow->isValid() && $flow->isFinished()) {
            return $this->redirectToRoute('app_success');
        }

        return $this->render('form.html.twig', [
            'form' => $flow->getStepForm(),
        ], new Response(null, $flow->isSubmitted() ? 422 : 200));
    }

    #[Route('/success', name: 'app_success')]
    public function success(): Response
    {
        return new Response('Success!');
    }
}

Template

{% extends 'base.html.twig' %}

{% block body %}
    <div class="container">
        <h2>Multi Step Form</h2>
        <div class="row text-center align-items-center">
            {% for step in form.vars.visible_steps %}
                {% if not loop.first and not loop.last %}<div class="col">➖</div>{% endif %}
                <div class="col">
                    {% if step.is_current_step %}
                        🔵
                    {% elseif step.index > form.vars.cursor.stepIndex %}
                        ⚪️
                    {% else %}
                        ☑️
                    {% endif %}
                    <div>
                        {{ step.name|title }}
                    </div>
                </div>
                {% if not loop.first and not loop.last %}<div class="col">➖</div>{% endif %}
            {% endfor %}
        </div>
        
        <div>
            {{ form(form) }}  //基本、これだけでok
        </div>
    </div>
{% endblock %}

実際の動き

感想

詰まったところとしては、Turbo Driveを使ったフォーム送信のようで、
data-turbo="false"にするか、以下のようにしないと次のステップへ進めない事象がありました。
ただSymfony6.2以降では以下のコード変更は不要とのことだったので、原因追及中です🤔

         return $this->render('form.html.twig', [
            'form' => $flow->getStepForm(),
-        ]);
+        ], new Response(null, $flow->isSubmitted() ? 422 : 200));

参考記事:
http://symfony.com/bundles/ux-turbo/current/index.html#3-form-response-code-changes

目次