PHP FieldItemListInterface::isEmpty方法代码示例

 /**
  * Helper function to normalize field items.
  *
  * @param \Drupal\Core\Field\FieldItemListInterface $field
  *   The field object.
  * @param string $format
  *   The format.
  * @param array $context
  *   The context array.
  *
  * @return array
  *   The array of normalized field items.
  */
 protected function normalizeFieldItems($field, $format, $context)
 {
     $normalized_field_items = array();
     if (!$field->isEmpty()) {
         foreach ($field as $field_item) {
             $normalized_field_items[] = $this->serializer->normalize($field_item, $format, $context);
         }
     }
     return $normalized_field_items;
 }

 /**
  * {@inheritdoc}
  */
 public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, FormStateInterface $form_state)
 {
     /** @var \Drupal\plugin\Plugin\Field\FieldType\PluginCollectionItemInterface $item */
     $item = $items[$delta];
     /** @var \Drupal\plugin\PluginType\PluginTypeInterface $plugin_type */
     $plugin_type = $item->getPluginType();
     $element = ['#delta' => $delta, '#field_definition' => $this->fieldDefinition, '#element_validate' => [[get_class(), 'validateFormElement']], '#plugin_type_id' => $plugin_type->getId(), '#plugin_selector_id' => $this->pluginDefinition['plugin_selector_id'], '#process' => [[get_class(), 'processFormElement']], '#selected_plugin' => $items->isEmpty() ? NULL : $items->get($delta)->getContainedPluginInstance()];
     $element['plugin_selector'] = static::getPluginSelector($form_state, $element)->buildSelectorForm([], $form_state);
     return $element;
 }

 /**
  * {@inheritdoc}
  */
 public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, FormStateInterface $form_state)
 {
     $tags = array();
     if (!$items->isEmpty()) {
         foreach ($items as $item) {
             $tags[] = isset($item->entity) ? $item->entity : entity_load('taxonomy_term', $item->target_id);
         }
     }
     $element += array('#type' => 'textfield', '#default_value' => taxonomy_implode_tags($tags), '#autocomplete_route_name' => $this->getSetting('autocomplete_route_name'), '#autocomplete_route_parameters' => array('entity_type' => $items->getEntity()->getEntityTypeId(), 'field_name' => $this->fieldDefinition->getName()), '#size' => $this->getSetting('size'), '#placeholder' => $this->getSetting('placeholder'), '#maxlength' => 1024, '#element_validate' => array('taxonomy_autocomplete_validate'));
     return $element;
 }

 /**
  * {@inheritdoc}
  */
 public function viewElements(FieldItemListInterface $items)
 {
     $elements = array();
     if ($items->isEmpty()) {
         // For fields with no value, just add the configured "empty" value.
         $elements[0] = array('#markup' => $this->getSetting('test_empty_string'));
     } else {
         foreach ($items as $delta => $item) {
             // This formatter only needs to output raw for testing.
             $elements[$delta] = array('#markup' => $item->value);
         }
     }
     return $elements;
 }

 /**
  * Gets the entity labels.
  */
 protected function getLabels(FieldItemListInterface $items, $delta)
 {
     if ($items->isEmpty()) {
         return array();
     }
     $entity_labels = array();
     // Load those entities and loop through them to extract their labels.
     $entities = entity_load_multiple($this->getFieldSetting('target_type'), $this->getEntityIds($items, $delta));
     foreach ($entities as $entity_id => $entity_item) {
         $label = $entity_item->label();
         $key = "{$label} ({$entity_id})";
         // Labels containing commas or quotes must be wrapped in quotes.
         $key = Tags::encode($key);
         $entity_labels[] = $key;
     }
     return $entity_labels;
 }

 /**
  * {@inheritdoc}
  */
 public function viewElements(FieldItemListInterface $items)
 {
     $elements = array();
     if (!$items->isEmpty()) {
         $header = array(t('Attachment'), t('Size'));
         $rows = array();
         foreach ($items as $delta => $item) {
             if ($item->isDisplayed() && $item->entity) {
                 $rows[] = array(array('data' => array('#theme' => 'file_link', '#file' => $item->entity)), array('data' => format_size($item->entity->getSize())));
             }
         }
         $elements[0] = array();
         if (!empty($rows)) {
             $elements[0] = array('#theme' => 'table__file_formatter_table', '#header' => $header, '#rows' => $rows);
         }
     }
     return $elements;
 }

 /**
  * {@inheritdoc}
  */
 public function viewElements(FieldItemListInterface $items, $langcode)
 {
     $element = array();
     // If there are no images, don't do anything else.
     if ($items->isEmpty()) {
         return array();
     }
     $entity = $items->getEntity();
     $field_instance = $items->getFieldDefinition();
     $entity_type_id = $entity->getEntityTypeId();
     $entity_id = $entity->id();
     $field_name = $field_instance->getName();
     $display_name = $this->viewMode;
     $add_js = TRUE;
     // Check for incompatible view modes - see issue #2217791
     if ($display_name == 'search_result' || $display_name == 'search_index') {
         $add_js = FALSE;
     }
     // The gallery shown in preview view will only display field data from the
     // previously saved version (that is the only version the XML generation
     // methods will have access to). Display a warning because of this.
     if (!empty($entity->in_preview)) {
         drupal_set_message(t('Juicebox galleries may not display correctly in preview mode. Any edits made to gallery data will only be visible after all changes are saved.'), 'warning', FALSE);
     }
     // Generate xml details.
     $xml_route_info = array('route_name' => 'juicebox.xml_field', 'route_parameters' => array('entityType' => $entity_type_id, 'entityId' => $entity_id, 'fieldName' => $field_name, 'displayName' => $display_name), 'options' => array('query' => $this->request->query->all()));
     // Try building the gallery and its XML.
     try {
         // Initialize the gallery.
         $gallery = $this->juicebox->newGallery($xml_route_info['route_parameters']);
         // Build the gallery.
         $this->buildGallery($gallery, $items);
         // Build field-specific contextual links.
         $contextual = $this->buildContextualLinks($xml_route_info, $entity_type_id);
         // Create a render array with the gallery markup.
         $element[0] = $this->juicebox->buildEmbed($gallery, $this->getSettings(), $xml_route_info, $add_js, $this->isPseudoInstance(), $contextual);
     } catch (\Exception $e) {
         $message = 'Exception building Juicebox embed code for field: !message in %function (line %line of %file).';
         watchdog_exception('juicebox', $e, $message);
     }
     return $element;
 }