Symfony 4 测验样式形式，嵌入式集合类型

Question

I'm trying to display a quiz style form where end-user gets presented with questions that can have one or multiple correct answers.

Entities:

Exam Question

<?php

namespace App\Entity;

use Doctrine\Common\Collections\ArrayCollection;
use Doctrine\Common\Collections\Collection;
use Doctrine\ORM\Mapping as ORM;
use Gedmo\Timestampable\Traits\TimestampableEntity;
use Ramsey\Uuid\UuidInterface;

/**
 * @ORM\Entity(repositoryClass="App\Repository\ExamQuestionRepository")
 */
class ExamQuestion
{
    use TimestampableEntity;

    /**
     * @var UuidInterface
     *
     * @ORM\Id
     * @ORM\Column(type="uuid", unique=true)
     * @ORM\GeneratedValue(strategy="CUSTOM")
     * @ORM\CustomIdGenerator(class="Ramsey\Uuid\Doctrine\UuidGenerator")
     */
    private $id;

    /**
     * @ORM\ManyToOne(targetEntity="App\Entity\Module", inversedBy="questions")
     * @ORM\JoinColumn(nullable=false)
     */
    private $module;

    /**
     * @ORM\Column(type="text")
     */
    private $text;

    /**
     * @ORM\OneToMany(targetEntity="App\Entity\ExamQuestionAnswer", mappedBy="question", orphanRemoval=true, cascade={"persist"})
     */
    private $examQuestionAnswers;

    /**
     * @ORM\Column(type="boolean")
     */
    private $hasMultipleAnswers;

    public function __construct()
    {
        $this->examQuestionAnswers = new ArrayCollection();
    }

    public function __toString()
    {
        return $this->text;
    }

    public function getId(): ?UuidInterface
    {
        return $this->id;
    }

    public function getModule(): ?Module
    {
        return $this->module;
    }

    public function setModule(?Module $module): self
    {
        $this->module = $module;

        return $this;
    }

    public function getText(): ?string
    {
        return $this->text;
    }

    public function setText(string $text): self
    {
        $this->text = $text;

        return $this;
    }

    /**
     * @return Collection|ExamQuestionAnswer[]
     */
    public function getExamQuestionAnswers(): Collection
    {
        return $this->examQuestionAnswers;
    }

    public function addExamQuestionAnswer(ExamQuestionAnswer $examQuestionAnswer): self
    {
        if (!$this->examQuestionAnswers->contains($examQuestionAnswer)) {
            $this->examQuestionAnswers[] = $examQuestionAnswer;
            $examQuestionAnswer->setQuestion($this);
        }

        return $this;
    }

    public function removeExamQuestionAnswer(ExamQuestionAnswer $examQuestionAnswer): self
    {
        if ($this->examQuestionAnswers->contains($examQuestionAnswer)) {
            $this->examQuestionAnswers->removeElement($examQuestionAnswer);
            // set the owning side to null (unless already changed)
            if ($examQuestionAnswer->getQuestion() === $this) {
                $examQuestionAnswer->setQuestion(null);
            }
        }

        return $this;
    }

    public function getHasMultipleAnswers(): ?bool
    {
        return $this->hasMultipleAnswers;
    }

    public function setHasMultipleAnswers(bool $hasMultipleAnswers): self
    {
        $this->hasMultipleAnswers = $hasMultipleAnswers;

        return $this;
    }
}

Exam Question Answer

<?php

namespace App\Entity;

use Doctrine\ORM\Mapping as ORM;
use Gedmo\Timestampable\Traits\TimestampableEntity;
use Ramsey\Uuid\UuidInterface;

/**
 * @ORM\Entity(repositoryClass="App\Repository\ExamQuestionRepository")
 */
class ExamQuestionAnswer
{
    use TimestampableEntity;

    /**
     * @var UuidInterface
     *
     * @ORM\Id
     * @ORM\Column(type="uuid", unique=true)
     * @ORM\GeneratedValue(strategy="CUSTOM")
     * @ORM\CustomIdGenerator(class="Ramsey\Uuid\Doctrine\UuidGenerator")
     */
    private $id;

    /**
     * @ORM\ManyToOne(targetEntity="App\Entity\ExamQuestion", inversedBy="examQuestionAnswers")
     * @ORM\JoinColumn(nullable=false)
     */
    private $question;

    /**
     * @ORM\Column(type="boolean")
     */
    private $isCorrect;

    /**
     * @ORM\Column(type="text")
     */
    private $text;

    /**
     * @ORM\Column(type="boolean", nullable=true)
     */
    private $selected;

    public function __toString()
    {
        return $this->text;
    }

    public function getId(): ?UuidInterface
    {
        return $this->id;
    }

    public function getQuestion(): ExamQuestion
    {
        return $this->question;
    }

    public function setQuestion(ExamQuestion $question): self
    {
        $this->question = $question;

        return $this;
    }

    public function getIsCorrect(): ?bool
    {
        return $this->isCorrect;
    }

    public function setIsCorrect(bool $isCorrect): self
    {
        $this->isCorrect = $isCorrect;

        return $this;
    }

    public function getText(): ?string
    {
        return $this->text;
    }

    public function setText(string $text): self
    {
        $this->text = $text;

        return $this;
    }

    public function getSelected(): ?bool
    {
        return $this->selected;
    }

    public function setSelected(?bool $selected): self
    {
        $this->selected = $selected;

        return $this;
    }
}

Exam Take

<?php

namespace App\Entity;

use Doctrine\Common\Collections\ArrayCollection;
use Doctrine\Common\Collections\Collection;
use Doctrine\ORM\Mapping as ORM;
use Gedmo\Timestampable\Traits\TimestampableEntity;
use Ramsey\Uuid\UuidInterface;

/**
 * @ORM\Entity(repositoryClass="App\Repository\ExamTakeRepository")
 */
class ExamTake
{
    use TimestampableEntity;

    /**
     * @var UuidInterface
     *
     * @ORM\Id
     * @ORM\Column(type="uuid", unique=true)
     * @ORM\GeneratedValue(strategy="CUSTOM")
     * @ORM\CustomIdGenerator(class="Ramsey\Uuid\Doctrine\UuidGenerator")
     */
    private $id;

    /**
     * @ORM\ManyToMany(targetEntity="App\Entity\ExamQuestion")
     */
    private $questions;

    /**
     * @ORM\ManyToOne(targetEntity="App\Entity\Module", inversedBy="examTakes")
     * @ORM\JoinColumn(nullable=false)
     */
    private $module;

    /**
     * @ORM\ManyToOne(targetEntity="App\Entity\Student", inversedBy="examTakes")
     * @ORM\JoinColumn(nullable=false)
     */
    private $student;

    /**
     * @ORM\Column(type="boolean", nullable=true)
     */
    private $passed;

    /**
     * @ORM\OneToMany(targetEntity="App\Entity\ExamQuestionStudentAnswer", mappedBy="examTake", orphanRemoval=true)
     */
    private $examQuestionStudentAnswers;

    public function __construct()
    {
        $this->questions = new ArrayCollection();
        $this->examQuestionStudentAnswers = new ArrayCollection();
    }

    public function getId(): ?UuidInterface
    {
        return $this->id;
    }

    /**
     * @return Collection|ExamQuestion[]
     */
    public function getQuestions(): Collection
    {
        return $this->questions;
    }

    public function addQuestion(ExamQuestion $question): self
    {
        if (!$this->questions->contains($question)) {
            $this->questions[] = $question;
        }

        return $this;
    }

    public function removeQuestion(ExamQuestion $question): self
    {
        if ($this->questions->contains($question)) {
            $this->questions->removeElement($question);
        }

        return $this;
    }

    public function getModule(): ?Module
    {
        return $this->module;
    }

    public function setModule(?Module $module): self
    {
        $this->module = $module;

        return $this;
    }

    public function getStudent(): ?Student
    {
        return $this->student;
    }

    public function setStudent(?Student $student): self
    {
        $this->student = $student;

        return $this;
    }

    public function getPassed(): ?bool
    {
        return $this->passed;
    }

    public function setPassed(?bool $passed): self
    {
        $this->passed = $passed;

        return $this;
    }

    /**
     * @return Collection|ExamQuestionStudentAnswer[]
     */
    public function getExamQuestionStudentAnswers(): Collection
    {
        return $this->examQuestionStudentAnswers;
    }

    public function addExamQuestionStudentAnswer(ExamQuestionStudentAnswer $examQuestionStudentAnswer): self
    {
        if (!$this->examQuestionStudentAnswers->contains($examQuestionStudentAnswer)) {
            $this->examQuestionStudentAnswers[] = $examQuestionStudentAnswer;
            $examQuestionStudentAnswer->setExamTake($this);
        }

        return $this;
    }

    public function removeExamQuestionStudentAnswer(ExamQuestionStudentAnswer $examQuestionStudentAnswer): self
    {
        if ($this->examQuestionStudentAnswers->contains($examQuestionStudentAnswer)) {
            $this->examQuestionStudentAnswers->removeElement($examQuestionStudentAnswer);
            // set the owning side to null (unless already changed)
            if ($examQuestionStudentAnswer->getExamTake() === $this) {
                $examQuestionStudentAnswer->setExamTake(null);
            }
        }

        return $this;
    }
}

And the forms:

class ExamTakeType extends AbstractType
{
    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder
            ->add('questions', CollectionType::class, [
                'entry_type' => ExamQuestionType::class,
                'allow_add' => false,
            ])
        ;
    }

    public function configureOptions(OptionsResolver $resolver)
    {
        $resolver->setDefaults([
            'data_class' => ExamTake::class,
        ]);
    }
}

class ExamQuestionType extends AbstractType
{
    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder
            ->add('text', TextType::class, [
                'attr' => ['readonly' => true],
            ])
            ->add('examQuestionAnswers', CollectionType::class, [
                'entry_type' => ExamQuestionAnswerType::class,
                'allow_add' => false,
            ])
        ;

    }

    public function configureOptions(OptionsResolver $resolver)
    {
        $resolver->setDefaults([
            'data_class' => ExamQuestion::class,
        ]);
    }
}

class ExamQuestionAnswerType extends AbstractType
{
    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder
            ->add('text');

        $builder->addEventListener(FormEvents::POST_SET_DATA, static function (FormEvent $event) {

            $form = $event->getForm();

            /** @var ExamQuestion $question */
            $question = $event->getData()->getQuestion();

            if ($question->getHasMultipleAnswers()) {
                $form
                    ->add('select', ChoiceType::class, [
                        'expanded' => true,
                        'multiple' => true,
                        'mapped' => false,
                    ]);
            } else {
                $form
                    ->add('select', ChoiceType::class, [
                        'expanded' => true,
                        'multiple' => false,
                        'mapped' => false,
                    ]);
            }
        });
    }

    public function configureOptions(OptionsResolver $resolver)
    {
        $resolver->setDefaults([
            'data_class' => ExamQuestionAnswer::class,
        ]);
    }
}

It seems i can't get the examQuestionAnswers field in collection displayed correctly. What i get is a collection of unrelated fields(inputs) if question has only one answer, and if question has multiple answers checkboxes are not shown. Any help is much appreciated!

Answer 1

The ChoiceType expects the choices attribute"

if ($question->getHasMultipleAnswers()) {
                $form
                    ->add('select', ChoiceType::class, [
                        'choices' => $question->getExamQuestionAnswers(),
                        'expanded' => true,
                        'multiple' => true,
                        'mapped' => false,
                    ]);
            } else {
                $form
                    ->add('select', ChoiceType::class, [
                        'choices' => $question->getExamQuestionAnswers(),
                        'expanded' => true,
                        'multiple' => false,
                        'mapped' => false,
                    ]);
            }

This will result in putting $examQuestionAnswers as choices to your ChoiceType. In case you get an exception change the type to EntityType(it inherits from ChoiceType) so choices should still work the same. You might also needed to implement either a __toString() method in your ExamQuestionAnswer entity or define choice_label attribute this should solve your problem in case it doesn't add a comment about what does not work and I'll implement it myself