class EntityReference in Drupal 8

Defines an 'entity_reference' data type.

This serves as 'entity' property of entity reference field items and gets its value set from the parent, i.e. LanguageItem.

The plain value of this reference is the entity object, i.e. an instance of \Drupal\Core\Entity\EntityInterface. For setting the value the entity object or the entity ID may be passed.

Note that the definition of the referenced entity's type is required, whereas defining referenceable entity bundle(s) is optional. A reference defining the type and bundle of the referenced entity can be created as following:

$definition = \Drupal\Core\Entity\EntityDefinition::create($entity_type)
  ->addConstraint('Bundle', $bundle);
\Drupal\Core\TypedData\DataReferenceDefinition::create('entity')
  ->setTargetDefinition($definition);

Plugin annotation

@DataType(
  id = "entity_reference",
  label = @Translation("Entity reference"),
  definition_class = "\Drupal\Core\TypedData\DataReferenceDefinition"
)

Hierarchy

• class \Drupal\Core\TypedData\TypedData implements PluginInspectionInterface, TypedDataInterface uses DependencySerializationTrait, StringTranslationTrait, TypedDataTrait
  • class \Drupal\Core\TypedData\DataReferenceBase implements DataReferenceInterface
    • class \Drupal\Core\Entity\Plugin\DataType\EntityReference

1 file declares its use of EntityReference

ContentEntityBase.php in core/lib/Drupal/Core/Entity/ContentEntityBase.php

2 string references to 'EntityReference'

views.view.test_entity_reference.yml in core/modules/system/tests/modules/entity_reference_test/config/install/views.view.test_entity_reference.yml

core/modules/system/tests/modules/entity_reference_test/config/install/views.view.test_entity_reference.yml

views.view.test_entity_reference_entity_test.yml in core/modules/system/tests/modules/entity_reference_test/config/install/views.view.test_entity_reference_entity_test.yml

core/modules/system/tests/modules/entity_reference_test/config/install/views.view.test_entity_reference_entity_test.yml

File

core/lib/Drupal/Core/Entity/Plugin/DataType/EntityReference.php, line 34

Namespace

Drupal\Core\Entity\Plugin\DataType

class EntityReference extends DataReferenceBase {

  /**
   * The entity ID.
   *
   * @var int|string
   */
  protected $id;

  /**
   * Gets the definition of the referenced entity.
   *
   * @return \Drupal\Core\Entity\TypedData\EntityDataDefinitionInterface
   *   The reference target's definition.
   */
  public function getTargetDefinition() {
    return $this->definition
      ->getTargetDefinition();
  }

  /**
   * Checks whether the target entity has not been saved yet.
   *
   * @return bool
   *   TRUE if the entity is new, FALSE otherwise.
   */
  public function isTargetNew() {

    // If only an ID is given, the reference cannot be a new entity.
    return !isset($this->id) && isset($this->target) && $this->target
      ->getValue()
      ->isNew();
  }

  /**
   * {@inheritdoc}
   */
  public function getTarget() {
    if (!isset($this->target) && isset($this->id)) {

      // If we have a valid reference, return the entity's TypedData adapter.
      $entity = \Drupal::entityTypeManager()
        ->getStorage($this
        ->getTargetDefinition()
        ->getEntityTypeId())
        ->load($this->id);
      $this->target = isset($entity) ? $entity
        ->getTypedData() : NULL;
    }
    return $this->target;
  }

  /**
   * {@inheritdoc}
   */
  public function getTargetIdentifier() {
    if (isset($this->id)) {
      return $this->id;
    }
    elseif ($entity = $this
      ->getValue()) {
      return $entity
        ->id();
    }
  }

  /**
   * {@inheritdoc}
   */
  public function setValue($value, $notify = TRUE) {
    unset($this->target);
    unset($this->id);

    // Both the entity ID and the entity object may be passed as value. The
    // reference may also be unset by passing NULL as value.
    if (!isset($value)) {
      $this->target = NULL;
    }
    elseif ($value instanceof EntityInterface) {
      $this->target = $value
        ->getTypedData();
    }
    elseif (!is_scalar($value) || $this
      ->getTargetDefinition()
      ->getEntityTypeId() === NULL) {
      throw new \InvalidArgumentException('Value is not a valid entity.');
    }
    else {
      $this->id = $value;
    }

    // Notify the parent of any changes.
    if ($notify && isset($this->parent)) {
      $this->parent
        ->onChange($this->name);
    }
  }

  /**
   * {@inheritdoc}
   */
  public function getString() {
    if ($entity = $this
      ->getValue()) {
      return $entity
        ->label();
    }
    return '';
  }

}

Members

Name	Modifiers	Type	Description	Overrides
DataReferenceBase::$target	protected	property	The referenced data.
DataReferenceBase::getValue	public	function	Gets the data value. Overrides TypedData::getValue
DependencySerializationTrait::$_entityStorages	protected	property	An array of entity type IDs keyed by the property name of their storages.
DependencySerializationTrait::$_serviceIds	protected	property	An array of service IDs keyed by property name used for serialization.
DependencySerializationTrait::__sleep	public	function		1
DependencySerializationTrait::__wakeup	public	function		2
EntityReference::$id	protected	property	The entity ID.
EntityReference::getString	public	function	Returns a string representation of the data. Overrides DataReferenceBase::getString
EntityReference::getTarget	public	function	Gets the referenced data. Overrides DataReferenceBase::getTarget
EntityReference::getTargetDefinition	public	function	Gets the definition of the referenced entity.
EntityReference::getTargetIdentifier	public	function	Gets the identifier of the referenced data. Overrides DataReferenceInterface::getTargetIdentifier
EntityReference::isTargetNew	public	function	Checks whether the target entity has not been saved yet.
EntityReference::setValue	public	function	Sets the data value. Overrides DataReferenceBase::setValue
StringTranslationTrait::$stringTranslation	protected	property	The string translation service.	1
StringTranslationTrait::formatPlural	protected	function	Formats a string containing a count of items.
StringTranslationTrait::getNumberOfPlurals	protected	function	Returns the number of plurals supported by a given language.
StringTranslationTrait::getStringTranslation	protected	function	Gets the string translation service.
StringTranslationTrait::setStringTranslation	public	function	Sets the string translation service to use.	2
StringTranslationTrait::t	protected	function	Translates a string to the current language or to a given language.
TypedData::$definition	protected	property	The data definition.	1
TypedData::$name	protected	property	The property name.
TypedData::$parent	protected	property	The parent typed data object.
TypedData::applyDefaultValue	public	function	Applies the default value. Overrides TypedDataInterface::applyDefaultValue	3
TypedData::createInstance	public static	function	Constructs a TypedData object given its definition and context. Overrides TypedDataInterface::createInstance
TypedData::getConstraints	public	function	Gets a list of validation constraints. Overrides TypedDataInterface::getConstraints	9
TypedData::getDataDefinition	public	function	Gets the data definition. Overrides TypedDataInterface::getDataDefinition
TypedData::getName	public	function	Returns the name of a property or item. Overrides TypedDataInterface::getName
TypedData::getParent	public	function	Returns the parent data structure; i.e. either complex data or a list. Overrides TypedDataInterface::getParent
TypedData::getPluginDefinition	public	function	Gets the definition of the plugin implementation. Overrides PluginInspectionInterface::getPluginDefinition
TypedData::getPluginId	public	function	Gets the plugin_id of the plugin instance. Overrides PluginInspectionInterface::getPluginId
TypedData::getPropertyPath	public	function	Returns the property path of the data. Overrides TypedDataInterface::getPropertyPath
TypedData::getRoot	public	function	Returns the root of the typed data tree. Overrides TypedDataInterface::getRoot
TypedData::setContext	public	function	Sets the context of a property or item via a context aware parent. Overrides TypedDataInterface::setContext
TypedData::validate	public	function	Validates the currently set data value. Overrides TypedDataInterface::validate
TypedData::__construct	public	function	Constructs a TypedData object given its definition and context.	3
TypedDataTrait::$typedDataManager	protected	property	The typed data manager used for creating the data types.
TypedDataTrait::getTypedDataManager	public	function	Gets the typed data manager.	2
TypedDataTrait::setTypedDataManager	public	function	Sets the typed data manager.	2