View display plugin "entity reference" not using translation

Question

UPDATE: This bug was just fixed in Issue 2174633 and Drupal v8.7.9 will no longer have this problem.

For some of my entity reference fields I'm using "Views: Filter by an entity reference views" as reference method. I've configured those views to use the current interface language for rendering (with fallback to default lang).

The interface language selection basically works (in other view blocks, or when previewing in /admin/structure/views), but it does not work when used as source for an entity reference field:

• In my admin interface I'm using I've got a paragraph with an ER field using such a view as source. The paragraph always shows the title in default lang
• On the frontend I've got a webform select field using the same view as source. The select options are always rendering in default lang.
• When using the default reference method I do get translated titles in both use cases.
• As stated above, the correct language is used in preview on /admin/structure/views

How can I select the correct language for my view-filtered ER fields?

(Please note that I can not use the interface language as filter criteria, because this would disable the language fallback.)

Answer 1

I have created a patch for @4k4's answer that also uses dependency injection.

To apply this patch:

Take the code snippet below and paste it into a new file e.g test.patch.

Then run git apply /path-to-file/test.patch.

For a UI only solution, see my other answer.

diff --git a/core/modules/views/src/Plugin/EntityReferenceSelection/ViewsSelection.php b/core/modules/views/src/Plugin/EntityReferenceSelection/ViewsSelection.php
index 79707af..e092ba9 100644
--- a/core/modules/views/src/Plugin/EntityReferenceSelection/ViewsSelection.php
+++ b/core/modules/views/src/Plugin/EntityReferenceSelection/ViewsSelection.php
@@ -4,6 +4,7 @@

 use Drupal\Core\DependencyInjection\DeprecatedServicePropertyTrait;
 use Drupal\Core\Entity\EntityReferenceSelection\SelectionPluginBase;
+use Drupal\Core\Entity\EntityRepositoryInterface;
 use Drupal\Core\Entity\EntityTypeManagerInterface;
 use Drupal\Core\Extension\ModuleHandlerInterface;
 use Drupal\Core\Form\FormStateInterface;
@@ -59,6 +60,13 @@ class ViewsSelection extends SelectionPluginBase implements ContainerFactoryPlug
    */
   protected $currentUser;

+  /**
+   * The entity repository.
+   *
+   * @var EntityRepositoryInterface
+   */
+  protected $entityRepository;
+
   /**
    * Constructs a new ViewsSelection object.
    *
@@ -74,13 +82,16 @@ class ViewsSelection extends SelectionPluginBase implements ContainerFactoryPlug
    *   The module handler service.
    * @param \Drupal\Core\Session\AccountInterface $current_user
    *   The current user.
+   * @param \Drupal\Core\Entity\EntityRepositoryInterface $entityRepository
+   *   The entity repository.
    */
-  public function __construct(array $configuration, $plugin_id, $plugin_definition, EntityTypeManagerInterface $entity_type_manager, ModuleHandlerInterface $module_handler, AccountInterface $current_user) {
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, EntityTypeManagerInterface $entity_type_manager, ModuleHandlerInterface $module_handler, AccountInterface $current_user, EntityRepositoryInterface $entityRepository) {
     parent::__construct($configuration, $plugin_id, $plugin_definition);

     $this->entityTypeManager = $entity_type_manager;
     $this->moduleHandler = $module_handler;
     $this->currentUser = $current_user;
+    $this->entityRepository = $entityRepository;
   }

   /**
@@ -93,7 +104,8 @@ public static function create(ContainerInterface $container, array $configuratio
       $plugin_definition,
       $container->get('entity_type.manager'),
       $container->get('module_handler'),
-      $container->get('current_user')
+      $container->get('current_user'),
+      $container->get('entity.repository')
     );
   }

@@ -231,6 +243,7 @@ public function getReferenceableEntities($match = NULL, $match_operator = 'CONTA
     if ($result) {
       foreach ($this->view->result as $row) {
         $entity = $row->_entity;
+        $entity = $this->entityRepository->getTranslationFromContext($entity);
         $return[$entity->bundle()][$entity->id()] = $entity->label();
       }
     }

Answer 2

Comparing TermSelection::getReferenceableEntities and ViewsSelection::getReferenceableEntities it seems like the Views entity reference selection plugin doesn't translate the entity before returning the entity labels. It should work with a core patch adding one line:

/core/modules/views/src/Plugin/EntityReferenceSelection/ViewsSelection.php:

public function getReferenceableEntities($match = NULL, $match_operator = 'CONTAINS', $limit = 0) {
  $display_name = $this->getConfiguration()['view']['display_name'];
  $arguments = $this->getConfiguration()['view']['arguments'];
  $result = [];
  if ($this->initializeView($match, $match_operator, $limit)) {
    // Get the results.
    $result = $this->view->executeDisplay($display_name, $arguments);
  }

  $return = [];
  if ($result) {
    foreach ($this->view->result as $row) {
      $entity = $row->_entity;
      // add this line to translate the entity
      $entity = \Drupal::service('entity.repository')->getTranslationFromContext($entity);
      $return[$entity->bundle()][$entity->id()] = $entity->label();
    }
  }
  return $return;
}

Edit:

This won't be necessary anymore, when https://www.drupal.org/project/drupal/issues/2174633 is fixed, then resolving the underlying problem, that the selection plugin ignores the views output.

Answer 3

Here's a UI solution if you don't want to apple a core patch.

You'll need to use the translation_views module.

Here's a screenshot of the needed filter configuration:

The logic is simple, if the node has no translations then show the original language, otherwise show the translation language.

I use the translation_views module to get the Translation counter filter.