以某种型号SYLIUS的表单类型显示图像

Question

我创建了一个具有属性“image”的新模型，我使用SyliusResourcesBundle生成了CRUD， 我想要实现的是在编辑表单类型中显示图像，我该怎么做？ thx提前

我的表单类型：

<?php

namespace AppBundle\Form\Type;

use Sylius\Bundle\ResourceBundle\Form\Type\DefaultResourceType as BaseSliderType;
use Symfony\Component\Form\Extension\Core\Type\FileType;
use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;


class SliderType extends AbstractType
{
    /**
     * {@inheritdoc}
     */
    public function buildForm(FormBuilderInterface $builder, array $options)
    {

    parent::buildForm($builder, $options);


    $builder->add('lib','text'
    );$builder->add('title','text'
    );
    $builder->add('description','text'
    );
    $builder->add('file',FileType::class
    );

}
public function getName()
{
    return 'app_slider';
}
}
?>

我的模特：

<?php

namespace AppBundle\Entity;
use Sylius\Component\Resource\Model\ResourceInterface;
use Doctrine\ORM\Mapping as ORM;

/**
 * Slider
 */
class Slider implements ResourceInterface, \Serializable
{
    /**
     * @var int
     */
    private $id;
/**
 * @var string
 */
private $lib;

/**
 * @var string
 */
private $title;

/**
 * @var string
 */
private $description;
private $file;

/**
 * @return mixed
 */
public function getFile()
{
    return $this->file;
}

/**
 * @param mixed $file
 */
public function setFile($file)
{
    $this->file = $file;
}


/**
 * Get id
 *
 * @return integer 
 */
public function getId()
{
    return $this->id;
}

/**
 * Set lib
 *
 * @param string $lib
 * @return Slider
 */
public function setLib($lib)
{
    $this->lib = $lib;

    return $this;
}

/**
 * Get lib
 *
 * @return string
 */
public function getLib()
{
    return $this->lib;
}

/**
 * Set title
 *
 * @param string $title
 * @return Slider
 */
public function setTitle($title)
{
    $this->title = $title;

    return $this;
}

/**
 * Get title
 *
 * @return string 
 */
public function getTitle()
{
    return $this->title;
}

/**
 * Set description
 *
 * @param string $description
 * @return Slider
 */
public function setDescription($description)
{
    $this->description = $description;

    return $this;
}

/**
 * Get description
 *
 * @return string 
 */
public function getDescription()
{
    return $this->description;
}
/**
 * @var string
 */
private $condition;


/**
 * Set condition
 *
 * @param string $condition
 * @return Slider
 */
public function setCondition($condition)
{
    $this->condition = $condition;

    return $this;
}

/**
 * Get condition
 *
 * @return string 
 */
public function getCondition()
{
    return $this->condition;
}

/** @see \Serializable::serialize() */
public function serialize()
{
    return serialize(array(
        $this->id,
        $this->lib,
        $this->title,
        $this->description,
        // see section on salt below
        // $this->salt,
    ));
}

/** @see \Serializable::unserialize() */
public function unserialize($serialized)
{
    list (
        $this->id,
        $this->lib,
        $this->title,
        $this->description,
        // see section on salt below
        // $this->salt
        ) = unserialize($serialized);
}
}