getContextualLinkGroup example

/** * {@inheritdoc} */
  public function getDerivativeDefinitions($base_plugin_definition) {
    // Create contextual links for all mappers.     $mappers = $this->mapperManager->getMappers();
    foreach ($mappers as $plugin_id => $mapper) {
      // @todo Contextual groups do not map to entity types in a predictable       // way. See https://www.drupal.org/node/2134841 to make them       // predictable.       $group_name = $mapper->getContextualLinkGroup();
      if (empty($group_name)) {
        continue;
      }

      /** @var \Drupal\config_translation\ConfigMapperInterface $mapper */
      $route_name = $mapper->getOverviewRouteName();
      $this->derivatives[$route_name] = $base_plugin_definition;
      $this->derivatives[$route_name]['config_translation_plugin_id'] = $plugin_id;
      $this->derivatives[$route_name]['class'] = '\Drupal\config_translation\Plugin\Menu\ContextualLink\ConfigTranslationContextualLink';
      $this->derivatives[$route_name]['route_name'] = $route_name;
      $this->derivatives[$route_name]['group'] = $group_name;
    }