class PictureBackgroundFormatter in Picture Background Formatter 8

Plugin implementation of the 'picture_background_formatter' formatter.

Plugin annotation


@FieldFormatter(
  id = "picture_background_formatter",
  label = @Translation("Picture background formatter"),
  field_types = {
    "image"
  }
)

Hierarchy

class \Drupal\Component\Plugin\PluginBase implements DerivativeInspectionInterface, PluginInspectionInterface
- class \Drupal\Core\Plugin\PluginBase uses DependencySerializationTrait, MessengerTrait, StringTranslationTrait
  - class \Drupal\Core\Field\PluginSettingsBase implements DependentPluginInterface, PluginSettingsInterface
    class \Drupal\Core\Field\FormatterBase implements FormatterInterface, ContainerFactoryPluginInterface
    class \Drupal\Core\Field\Plugin\Field\FieldFormatter\EntityReferenceFormatterBase
    class \Drupal\file\Plugin\Field\FieldFormatter\FileFormatterBase
    class \Drupal\image\Plugin\Field\FieldFormatter\ImageFormatterBase
    class \Drupal\responsive_image\Plugin\Field\FieldFormatter\ResponsiveImageFormatter implements ContainerFactoryPluginInterface
    class \Drupal\picture_background_formatter\Plugin\Field\FieldFormatter\PictureBackgroundFormatter implements ContainerFactoryPluginInterface

Expanded class hierarchy of PictureBackgroundFormatter

File

src/Plugin/Field/FieldFormatter/PictureBackgroundFormatter.php, line 28

Namespace

Drupal\picture_background_formatter\Plugin\Field\FieldFormatter

View source

class PictureBackgroundFormatter extends ResponsiveImageFormatter implements ContainerFactoryPluginInterface {

  /**
   * {@inheritdoc}
   */
  public static function defaultSettings() {
    return [
      'selector' => '',
    ] + parent::defaultSettings();
  }

  /**
   * {@inheritdoc}
   */
  public function settingsForm(array $form, FormStateInterface $form_state) {
    $elements = parent::settingsForm($form, $form_state);
    unset($elements['image_link']);
    $token_types = [
      $this->fieldDefinition
        ->getTargetEntityTypeId(),
    ];
    $elements['selector'] = array(
      '#type' => 'textfield',
      '#title' => t('Selector'),
      '#required' => TRUE,
      '#description' => t('CSS Selector for background image.'),
      '#default_value' => $this
        ->getSetting('selector'),
      '#token_types' => $token_types,
      '#element_validate' => 'token_element_validate',
    );
    $elements['tokens'] = [
      '#theme' => 'token_tree_link',
      '#token_types' => $token_types,
      '#global_types' => TRUE,
      '#show_nested' => FALSE,
    ];
    return $elements;
  }

  /**
   * {@inheritdoc}
   */
  public function settingsSummary() {
    $summary = [];
    $responsive_image_style = $this->responsiveImageStyleStorage
      ->load($this
      ->getSetting('responsive_image_style'));
    if ($responsive_image_style) {
      $summary[] = t('Responsive image style: @responsive_image_style', [
        '@responsive_image_style' => $responsive_image_style
          ->label(),
      ]);
    }
    else {
      $summary[] = t('Select a responsive image style.');
    }
    return $summary;
  }

  /**
   * {@inheritdoc}
   */
  public function viewElements(FieldItemListInterface $items, $langcode) {
    $elements = [];
    $entity = $items
      ->getEntity();

    // Load the files to render.
    $files = $this
      ->getEntitiesToView($items, $langcode);

    // Early opt-out if the field is empty.
    if (empty($files)) {
      return $elements;
    }
    return $this
      ->build_element($files, $entity);
  }

  /**
   * Build the inline css style based on a set of files and a selector.
   *
   * @param \Drupal\Core\Entity\EntityInterface[] $files
   *   The array of referenced files to display, keyed by delta.
   * @param \Drupal\Core\Entity\EntityInterface $entity
   *   The parent entity the field belongs to. Used for token replacement in the
   *   selector.
   *
   * @return array
   */
  protected function build_element($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;
  }

  /**
   * CSS Generator Helper Function.
   *
   * @param ImageItem $image
   *   URI of the field image.
   * @param array $responsive_image_style
   *   Desired picture mapping to generate CSS.
   * @param string $selector
   *   CSS selector to target.
   *
   * @return string
   *   Generated background image CSS.
   *
   */
  protected function generate_background_css($image, $responsive_image_style, $selector) {
    $css = "";
    $breakpoints = \Drupal::service('breakpoint.manager')
      ->getBreakpointsByGroup($responsive_image_style
      ->getBreakpointGroup());
    foreach (array_reverse($responsive_image_style
      ->getKeyedImageStyleMappings()) as $breakpoint_id => $multipliers) {
      if (isset($breakpoints[$breakpoint_id])) {
        $multipliers = array_reverse($multipliers);
        $query = $breakpoints[$breakpoint_id]
          ->getMediaQuery();
        if ($query != "") {
          $css .= ' @media ' . $query . ' {';
        }
        foreach ($multipliers as $multiplier => $mapping) {
          $multiplier = rtrim($multiplier, "x");
          if ($mapping['image_mapping_type'] != 'image_style') {
            continue;
          }
          if ($mapping['image_mapping'] == "_original image_") {
            $url = file_create_url($image
              ->getFileUri());
          }
          else {
            $url = ImageStyle::load($mapping['image_mapping'])
              ->buildUrl($image
              ->getFileUri());
          }
          if ($multiplier != 1) {
            $css .= ' @media (-webkit-min-device-pixel-ratio: ' . $multiplier . '), (min-resolution: ' . $multiplier * 96 . 'dpi), (min-resolution: ' . $multiplier . 'dppx) {';
          }
          $css .= $selector . ' {background-image: url(' . $url . ');}';
          if ($multiplier != 1) {
            $css .= '}';
          }
        }
        if ($query != "") {
          $css .= '}';
        }
      }
    }
    return $css;
  }

}

Members

Name	Modifiers	Type	Description	Overrides
DependencySerializationTrait::$_entityStorages	protected	property	An array of entity type IDs keyed by the property name of their storages.
DependencySerializationTrait::$_serviceIds	protected	property	An array of service IDs keyed by property name used for serialization.
DependencySerializationTrait::__sleep	public	function		1
DependencySerializationTrait::__wakeup	public	function		2
EntityReferenceFormatterBase::prepareView	public	function	Loads the entities referenced in that field across all the entities being viewed. Overrides FormatterBase::prepareView
EntityReferenceFormatterBase::view	public	function	Overrides FormatterBase::view
FileFormatterBase::checkAccess	protected	function	Checks access to the given entity. Overrides EntityReferenceFormatterBase::checkAccess
FileFormatterBase::needsEntityLoad	protected	function	Returns whether the entity referenced by an item needs to be loaded. Overrides EntityReferenceFormatterBase::needsEntityLoad	1
FormatterBase::$fieldDefinition	protected	property	The field definition.
FormatterBase::$label	protected	property	The label display setting.
FormatterBase::$settings	protected	property	The formatter settings. Overrides PluginSettingsBase::$settings
FormatterBase::$viewMode	protected	property	The view mode.
FormatterBase::getFieldSetting	protected	function	Returns the value of a field setting.
FormatterBase::getFieldSettings	protected	function	Returns the array of field settings.
FormatterBase::isApplicable	public static	function	Returns if the formatter can be used for the provided field. Overrides FormatterInterface::isApplicable	14
ImageFormatterBase::getEntitiesToView	protected	function	Returns the referenced entities for display. Overrides EntityReferenceFormatterBase::getEntitiesToView
MessengerTrait::$messenger	protected	property	The messenger.	29
MessengerTrait::messenger	public	function	Gets the messenger.	29
MessengerTrait::setMessenger	public	function	Sets the messenger.
PictureBackgroundFormatter::build_element	protected	function	Build the inline css style based on a set of files and a selector.
PictureBackgroundFormatter::defaultSettings	public static	function	Defines the default settings for this plugin. Overrides ResponsiveImageFormatter::defaultSettings
PictureBackgroundFormatter::generate_background_css	protected	function	CSS Generator Helper Function.
PictureBackgroundFormatter::settingsForm	public	function	Returns a form to configure settings for the formatter. Overrides ResponsiveImageFormatter::settingsForm
PictureBackgroundFormatter::settingsSummary	public	function	Returns a short summary for the current formatter settings. Overrides ResponsiveImageFormatter::settingsSummary
PictureBackgroundFormatter::viewElements	public	function	Builds a renderable array for a field value. Overrides ResponsiveImageFormatter::viewElements	1
PluginBase::$configuration	protected	property	Configuration information passed into the plugin.	1
PluginBase::$pluginDefinition	protected	property	The plugin implementation definition.	1
PluginBase::$pluginId	protected	property	The plugin_id.
PluginBase::DERIVATIVE_SEPARATOR		constant	A string which is used to separate base plugin IDs from the derivative ID.
PluginBase::getBaseId	public	function	Gets the base_plugin_id of the plugin instance. Overrides DerivativeInspectionInterface::getBaseId
PluginBase::getDerivativeId	public	function	Gets the derivative_id of the plugin instance. Overrides DerivativeInspectionInterface::getDerivativeId
PluginBase::getPluginDefinition	public	function	Gets the definition of the plugin implementation. Overrides PluginInspectionInterface::getPluginDefinition	3
PluginBase::getPluginId	public	function	Gets the plugin_id of the plugin instance. Overrides PluginInspectionInterface::getPluginId
PluginBase::isConfigurable	public	function	Determines if the plugin is configurable.
PluginSettingsBase::$defaultSettingsMerged	protected	property	Whether default settings have been merged into the current $settings.
PluginSettingsBase::$thirdPartySettings	protected	property	The plugin settings injected by third party modules.
PluginSettingsBase::getSetting	public	function	Returns the value of a setting, or its default value if absent. Overrides PluginSettingsInterface::getSetting
PluginSettingsBase::getSettings	public	function	Returns the array of settings, including defaults for missing settings. Overrides PluginSettingsInterface::getSettings
PluginSettingsBase::getThirdPartyProviders	public	function	Gets the list of third parties that store information. Overrides ThirdPartySettingsInterface::getThirdPartyProviders
PluginSettingsBase::getThirdPartySetting	public	function	Gets the value of a third-party setting. Overrides ThirdPartySettingsInterface::getThirdPartySetting
PluginSettingsBase::getThirdPartySettings	public	function	Gets all third-party settings of a given module. Overrides ThirdPartySettingsInterface::getThirdPartySettings
PluginSettingsBase::mergeDefaults	protected	function	Merges default settings values into $settings.
PluginSettingsBase::onDependencyRemoval	public	function	Informs the plugin that some configuration it depends on will be deleted. Overrides PluginSettingsInterface::onDependencyRemoval	3
PluginSettingsBase::setSetting	public	function	Sets the value of a setting for the plugin. Overrides PluginSettingsInterface::setSetting
PluginSettingsBase::setSettings	public	function	Sets the settings for the plugin. Overrides PluginSettingsInterface::setSettings
PluginSettingsBase::setThirdPartySetting	public	function	Sets the value of a third-party setting. Overrides ThirdPartySettingsInterface::setThirdPartySetting
PluginSettingsBase::unsetThirdPartySetting	public	function	Unsets a third-party setting. Overrides ThirdPartySettingsInterface::unsetThirdPartySetting
ResponsiveImageFormatter::$currentUser	protected	property	The current user.
ResponsiveImageFormatter::$imageStyleStorage	protected	property
ResponsiveImageFormatter::$linkGenerator	protected	property	The link generator.
ResponsiveImageFormatter::$responsiveImageStyleStorage	protected	property
ResponsiveImageFormatter::calculateDependencies	public	function	Calculates dependencies for the configured plugin. Overrides PluginSettingsBase::calculateDependencies
ResponsiveImageFormatter::create	public static	function	Creates an instance of the plugin. Overrides FormatterBase::create
ResponsiveImageFormatter::__construct	public	function	Constructs a ResponsiveImageFormatter object. Overrides FormatterBase::__construct
StringTranslationTrait::$stringTranslation	protected	property	The string translation service.	1
StringTranslationTrait::formatPlural	protected	function	Formats a string containing a count of items.
StringTranslationTrait::getNumberOfPlurals	protected	function	Returns the number of plurals supported by a given language.
StringTranslationTrait::getStringTranslation	protected	function	Gets the string translation service.
StringTranslationTrait::setStringTranslation	public	function	Sets the string translation service to use.	2
StringTranslationTrait::t	protected	function	Translates a string to the current language or to a given language.

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class PictureBackgroundFormatter in Picture Background Formatter 8

Plugin annotation

Hierarchy

File

Namespace

Members

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