public function PDFPreviewFormatter::viewElements in PDFPreview 8

Same name and namespace in other branches

1. 2.0.x src/Plugin/Field/FieldFormatter/PdfPreviewFormatter.php \Drupal\pdfpreview\Plugin\Field\FieldFormatter\PdfPreviewFormatter::viewElements()

Builds a renderable array for a field value.

Parameters

\Drupal\Core\Field\FieldItemListInterface $items: The field values to be rendered.

string $langcode: The language that should be used to render the field.

Return value

array A renderable array for $items, as an array of child elements keyed by consecutive numeric indexes starting from 0.

Overrides ImageFormatter::viewElements

File

src/Plugin/Field/FieldFormatter/PDFPreviewFormatter.php, line 150

Class

PDFPreviewFormatter

Plugin implementation of the 'pdfpreview' formatter.

Namespace

Drupal\pdfpreview\Plugin\Field\FieldFormatter

Code

public function viewElements(FieldItemListInterface $items, $langcode) {
  $elements = [];
  $files = $this
    ->getEntitiesToView($items, $langcode);

  // Early opt-out if the field is empty.
  if (empty($files)) {
    return $elements;
  }
  $url = NULL;
  $image_link_setting = $this
    ->getSetting('image_link');

  // Check if the formatter involves a link.
  if ($image_link_setting == 'content') {
    $entity = $items
      ->getEntity();
    if (!$entity
      ->isNew()) {
      $url = $entity
        ->toUrl();
    }
  }
  elseif ($image_link_setting == 'file') {
    $link_file = TRUE;
  }
  $image_style_setting = $this
    ->getSetting('image_style');

  // Collect cache tags to be added for each item in the field.
  $cache_tags = [];
  if (!empty($image_style_setting)) {
    $image_style = $this->imageStyleStorage
      ->load($image_style_setting);
    $cache_tags = $image_style
      ->getCacheTags();
  }

  /** @var \Drupal\file\Entity\File $file */
  foreach ($files as $delta => $file) {
    $cache_contexts = [];
    if (isset($link_file)) {
      $image_uri = $file
        ->getFileUri();

      // @todo Wrap in file_url_transform_relative(). This is currently
      // impossible. As a work-around, we currently add the 'url.site' cache
      // context to ensure different file URLs are generated for different
      // sites in a multisite setup, including HTTP and HTTPS versions of the
      // same site. Fix in https://www.drupal.org/node/2646744.
      $url = Url::fromUri(file_create_url($image_uri));
      $cache_contexts[] = 'url.site';
    }
    $cache_tags = Cache::mergeTags($cache_tags, $file
      ->getCacheTags());

    // Extract field item attributes for the theme function, and unset them
    // from the $item so that the field template does not re-render them.
    $item = $file->_referringItem;
    $item_attributes = $item->_attributes;
    unset($item->_attributes);
    if (isset($item->description)) {
      $item_attributes['alt'] = $item->description;
      $item_attributes['title'] = $item->description;
    }
    $item_attributes['class'][] = 'pdfpreview-file';

    // Separate the PDF previews from the other files.
    $show_preview = FALSE;
    if ($file
      ->getMimeType() == 'application/pdf') {
      $preview_uri = $this->pdfPreviewGenerator
        ->getPDFPreview($file);
      $preview = $this->imageFactory
        ->get($preview_uri);
      if ($preview
        ->isValid()) {
        $show_preview = TRUE;
        $item->uri = $preview_uri;
        $item->width = $preview
          ->getWidth();
        $item->height = $preview
          ->getHeight();
        $elements[$delta] = [
          '#theme' => 'image_formatter',
          '#item' => $item,
          '#item_attributes' => $item_attributes,
          '#image_style' => $image_style_setting,
          '#url' => $url,
          '#cache' => [
            'tags' => $cache_tags,
            'contexts' => $cache_contexts,
          ],
        ];
      }
    }
    if (!$show_preview) {
      $elements[$delta] = [
        '#theme' => 'file_link',
        '#file' => $file,
        '#cache' => [
          'tags' => $file
            ->getCacheTags(),
        ],
      ];
    }
    $elements[$delta]['#description'] = $item->description;
    $elements[$delta]['#theme_wrappers'][] = 'pdfpreview_formatter';
    $elements[$delta]['#settings'] = $this
      ->getSettings();
    $elements[$delta]['#fid'] = $file
      ->id();
  }
  return $elements;
}