public function PagerExamplePage::getContent in Examples for Developers 8

Same name and namespace in other branches

1. 3.x modules/pager_example/src/Controller/PagerExamplePage.php \Drupal\pager_example\Controller\PagerExamplePage::getContent()

Content callback for the pager_example.page route.

1 string reference to 'PagerExamplePage::getContent'

pager_example.routing.yml in pager_example/pager_example.routing.yml

pager_example/pager_example.routing.yml

File

pager_example/src/Controller/PagerExamplePage.php, line 62

Class

PagerExamplePage

Controller for pager_example.page route.

Namespace

Drupal\pager_example\Controller

Code

public function getContent() {

  // First we'll tell the user what's going on. This content can be found
  // in the twig template file: templates/description.html.twig. It will be
  // inserted by the theming function pager_example_description().
  $build = [
    'description' => [
      '#theme' => 'pager_example_description',
      '#description' => $this
        ->t('description'),
      '#attributes' => [],
    ],
  ];

  // Ensure that this page's cache is invalidated when nodes have been
  // published, unpublished, added or deleted; and when user permissions
  // change.
  $build['#cache']['tags'][] = 'node_list';
  $build['#cache']['contexts'][] = 'user.permissions';

  // Now we want to get our tabular data. We select nodes from node storage
  // limited by 2 per page and sort by nid DESC because we want to show newest
  // node first. Additionally, we check that the user has permission to
  // view the node.
  $query = $this->nodeStorage
    ->getQuery()
    ->sort('nid', 'DESC')
    ->addTag('node_access')
    ->pager(2);

  // The node_access tag does not trigger a check on whether a user has the
  // ability to view unpublished content. The 'bypass node access' permission
  // is really more than we need. But, there is no separate permission for
  // viewing unpublished content. There is a permission to 'view own
  // unpublished content', but we don't have a good way of using that in this
  // query. So, unfortunately this query will incorrectly eliminate even those
  // unpublished nodes that the user may, in fact, be allowed to view.
  if (!$this->currentUser
    ->hasPermission('bypass node access')) {
    $query
      ->condition('status', 1);
  }
  $entity_ids = $query
    ->execute();
  $nodes = $this->nodeStorage
    ->loadMultiple($entity_ids);

  // We are going to output the results in a table so we set up the rows.
  $rows = [];
  foreach ($nodes as $node) {

    // There are certain things (besides unpublished nodes) that the
    // node_access tag won't prevent from being seen. The only way to get at
    // those is by explicitly checking for (view) access on a node-by-node
    // basis. In order to prevent the pager from looking strange, we will
    // "mask" these nodes that should not be accessible. If we don't do this
    // masking, it's possible that we'd have lots of pages that don't show any
    // content.
    $rows[] = [
      'nid' => $node
        ->access('view') ? $node
        ->id() : $this
        ->t('XXXXXX'),
      'title' => $node
        ->access('view') ? $node
        ->getTitle() : $this
        ->t('Redacted'),
    ];
  }

  // Build a render array which will be themed as a table with a pager.
  $build['pager_example'] = [
    '#type' => 'table',
    '#header' => [
      $this
        ->t('NID'),
      $this
        ->t('Title'),
    ],
    '#rows' => $rows,
    '#empty' => $this
      ->t('There are no nodes to display. Please <a href=":url">create a node</a>.', [
      ':url' => Url::fromRoute('node.add', [
        'node_type' => 'page',
      ])
        ->toString(),
    ]),
  ];

  // Add our pager element so the user can choose which pagination to see.
  // This will add a '?page=1' fragment to the links to subsequent pages.
  $build['pager'] = [
    '#type' => 'pager',
    '#weight' => 10,
  ];
  return $build;
}