field_multiple_limit.module in Field multiple limit 8

Provides field formatter settings to limit the number of values to display on multi-value fields.

File

field_multiple_limit.module

<?php

/**
 * @file
 * Provides field formatter settings to limit the number of values to display on
 * multi-value fields.
 */

/**
 * @todo how will this work with HTML5 number inputs?
 *  can we deprecate it?
 */
define('FIELD_MULTIPLE_LIMIT_ALL', -1);

/**
 * Implements hook_field_formatter_settings_summary_alter().
 */
function field_multiple_limit_field_formatter_settings_summary_alter(&$summary, $context) {
  if ($context['field_definition']
    ->getFieldStorageDefinition()
    ->isMultiple()) {

    // Only display count + offset if the limit_values is TRUE
    if ($context['formatter']
      ->getThirdPartySetting('field_multiple_limit', 'limit_values')) {
      $count = $context['formatter']
        ->getThirdPartySetting('field_multiple_limit', 'count');
      if (!empty($count)) {
        $summary[] = \Drupal::translation()
          ->formatPlural($count, 'Display 1 value', 'Display @count values');
      }
      $offset = $context['formatter']
        ->getThirdPartySetting('field_multiple_limit', 'offset');
      if (!empty($offset)) {
        $summary[] = \Drupal::translation()
          ->formatPlural($offset, 'Skip 1 value', 'Skip @count values');
      }
    }
  }
}

/**
 * Implements hook_field_formatter_third_party_settings_form().
 * 
 * Targets multivalued fields only.
 *
 * @todo #states property for the limit + offset, depending on the new boolean.
 *
 */
function field_multiple_limit_field_formatter_third_party_settings_form(\Drupal\Core\Field\FormatterInterface $plugin, \Drupal\Core\Field\FieldDefinitionInterface $field_definition, $view_mode, $form, \Drupal\Core\Form\FormStateInterface $form_state) {
  if ($field_definition
    ->getFieldStorageDefinition()
    ->isMultiple()) {
    $element['limit_values'] = array(
      '#type' => 'checkbox',
      '#title' => t('Limit the number of values to display'),
      '#default_value' => $plugin
        ->getThirdPartySetting('field_multiple_limit', 'limit_values'),
    );
    $element['count'] = array(
      '#type' => 'number',
      '#title' => t('Number of values to display'),
      '#min' => 1,
      '#default_value' => $plugin
        ->getThirdPartySetting('field_multiple_limit', 'count'),
    );
    $element['offset'] = array(
      '#type' => 'number',
      '#title' => t('Number of values to skip'),
      '#min' => 0,
      '#default_value' => $plugin
        ->getThirdPartySetting('field_multiple_limit', 'offset'),
    );
    return $element;
  }
}

/**
 * Implements hook_field_attach_view_alter().
 */
function field_multiple_limit_field_attach_view_alter(&$output, $context) {
  foreach (element_children($output) as $field_name) {
    $entity_type = $output[$field_name]['#entity_type'];
    $bundle = $output[$field_name]['#bundle'];
    $info = field_formatter_settings_get_instance_display_settings($entity_type, $field_name, $bundle, $context['view_mode']);
    $limit = empty($info['field_multiple_limit']) ? FIELD_MULTIPLE_LIMIT_ALL : $info['field_multiple_limit'];
    $offset = empty($info['field_multiple_limit_offset']) ? 0 : $info['field_multiple_limit_offset'];
    if ($offset > 0 || $limit != FIELD_MULTIPLE_LIMIT_ALL && $output[$field_name]['#items'] > $limit) {
      $element =& $output[$field_name];
      $count = 1;
      foreach ($element['#items'] as $delta => $item) {
        if ($delta < $offset) {
          $element[$delta]['#access'] = FALSE;
          continue;
        }
        if ($limit != FIELD_MULTIPLE_LIMIT_ALL && $count > $limit) {

          // @todo This is definitely not the best way to do that. Ideally we
          // should alter the data in such way that no unwanted results are
          // returned.
          $element[$delta]['#access'] = FALSE;
        }
        $count++;
      }
    }
  }
}

Functions

Name	Description
field_multiple_limit_field_attach_view_alter	Implements hook_field_attach_view_alter().
field_multiple_limit_field_formatter_settings_summary_alter	Implements hook_field_formatter_settings_summary_alter().
field_multiple_limit_field_formatter_third_party_settings_form	Implements hook_field_formatter_third_party_settings_form().

Constants

Name	Description
FIELD_MULTIPLE_LIMIT_ALL	@todo how will this work with HTML5 number inputs? can we deprecate it?