protected function PictureBackgroundFormatter::build_element in Picture Background Formatter 8

Build the inline css style based on a set of files and a selector.

Parameters

\Drupal\Core\Entity\EntityInterface[] $files: The array of referenced files to display, keyed by delta.

\Drupal\Core\Entity\EntityInterface $entity: The parent entity the field belongs to. Used for token replacement in the selector.

Return value

array

2 calls to PictureBackgroundFormatter::build_element()

PictureBackgroundFormatter::viewElements in src/Plugin/Field/FieldFormatter/PictureBackgroundFormatter.php

Builds a renderable array for a field value.

PictureBackgroundFormatterMedia::viewElements in src/Plugin/Field/FieldFormatter/PictureBackgroundFormatterMedia.php

Builds a renderable array for a field value.

File

src/Plugin/Field/FieldFormatter/PictureBackgroundFormatter.php, line 114

Class

PictureBackgroundFormatter

Plugin implementation of the 'picture_background_formatter' formatter.

Namespace

Drupal\picture_background_formatter\Plugin\Field\FieldFormatter

Code

protected function build_element($files, $entity) {
  $elements = [];
  $css = "";
  $selector = $this
    ->getSetting('selector');
  $selector = \Drupal::token()
    ->replace($selector, [
    $entity
      ->getEntityTypeId() => $entity,
  ], [
    'clear' => TRUE,
  ]);

  // Collect cache tags to be added for each item in the field.
  $responsive_image_style = $this->responsiveImageStyleStorage
    ->load($this
    ->getSetting('responsive_image_style'));
  $image_styles_to_load = [];
  $cache_tags = [];
  if ($responsive_image_style) {
    $cache_tags = Cache::mergeTags($cache_tags, $responsive_image_style
      ->getCacheTags());
    $image_styles_to_load = $responsive_image_style
      ->getImageStyleIds();
  }
  $image_styles = $this->imageStyleStorage
    ->loadMultiple($image_styles_to_load);
  foreach ($image_styles as $image_style) {
    $cache_tags = Cache::mergeTags($cache_tags, $image_style
      ->getCacheTags());
  }
  foreach ($files as $file) {
    $css .= $this
      ->generate_background_css($file, $responsive_image_style, $selector);
  }
  if (!empty($css)) {

    // Use the selector in the id to avoid collisions with multiple background
    // formatters on the same page.
    $id = 'picture-background-formatter-' . $selector;
    $elements['#attached']['html_head'][] = [
      [
        '#tag' => 'style',
        '#value' => new CSSSnippet($css),
      ],
      $id,
    ];
  }
  return $elements;
}