public function SubtitleFormatter::viewInstantArticle in Facebook Instant Articles 8.2

Same name and namespace in other branches

1. 3.x src/Plugin/Field/FieldFormatter/SubtitleFormatter.php \Drupal\fb_instant_articles\Plugin\Field\FieldFormatter\SubtitleFormatter::viewInstantArticle()

Modifies the given instant article with the contents of this field.

Parameters

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

\Facebook\InstantArticles\Elements\InstantArticle $article: Instant article object to modify, rendering the contents of this field into it.

string $region: The Instant Article region name that the contents of this field should be rendered into.

\Symfony\Component\Serializer\Normalizer\NormalizerInterface $normalizer: Normalizer in case the formatter needs to recursively normalize, eg. in the case of a entity reference field.

string $langcode: (optional) The language that should be used to render the field. Defaults to the current content language.

Overrides InstantArticleFormatterInterface::viewInstantArticle

File

src/Plugin/Field/FieldFormatter/SubtitleFormatter.php, line 123

Class

SubtitleFormatter

Plugin implementation of the 'fbia_subtitle' formatter.

Namespace

Drupal\fb_instant_articles\Plugin\Field\FieldFormatter

Code

public function viewInstantArticle(FieldItemListInterface $items, InstantArticle $article, $region, NormalizerInterface $normalizer, $langcode = NULL) {

  // Subtitles only go in the header. Create one if it doesn't exist yet and
  // ignore the given $region.
  $header = $article
    ->getHeader();
  if (!$header) {
    $header = Header::create();
    $article
      ->withHeader($header);
  }

  // Note that there can only be one subtitle. We use the first value as the
  // subtitle.
  if (!$items
    ->isEmpty()) {
    $item = $items
      ->get(0);

    // For formatted text, pass the text through the filters and then through
    // the FBIA transformer, before adding it to the article.
    // in the subtitle.
    if (in_array($items
      ->getFieldDefinition()
      ->getType(), [
      'text',
      'text_long',
      'text_with_summary',
    ])) {
      $subtitle_render_array = [
        '#type' => 'processed_text',
        '#text' => $item->value,
        '#format' => $item->format,
        '#langcode' => $item
          ->getLangcode(),
      ];
      $subtitle_string = (string) $this->renderer
        ->renderPlain($subtitle_render_array);

      // Here we create a Facebook H2 element, passing it as context to the
      // transformer. It will therefore append any allowed elements, per the
      // rules defined in the constructor (only a, i, b, em and strong tags),
      // to the header. What that means is that tags will be stripped from the
      // input string except a, i, b, em and strong.
      $subtitle = H2::create();
      $this->transformer
        ->transformString($subtitle, $subtitle_string);
    }
    else {
      $subtitle = $item
        ->getString();
    }
    $header
      ->withSubTitle($subtitle);
  }
}