function template_preprocess_book_navigation in Drupal 7

Same name and namespace in other branches

1. 8 core/modules/book/book.module \template_preprocess_book_navigation()
2. 6 modules/book/book.module \template_preprocess_book_navigation()
3. 9 core/modules/book/book.module \template_preprocess_book_navigation()

Processes variables for book-navigation.tpl.php.

Parameters

$variables: An associative array containing the following key:

• book_link

See also

book-navigation.tpl.php

File

modules/book/book.module, line 1095

Allows users to create and organize related content in an outline.

Code

function template_preprocess_book_navigation(&$variables) {
  $book_link = $variables['book_link'];

  // Provide extra variables for themers. Not needed by default.
  $variables['book_id'] = $book_link['bid'];
  $variables['book_title'] = check_plain($book_link['link_title']);
  $variables['book_url'] = 'node/' . $book_link['bid'];
  $variables['current_depth'] = $book_link['depth'];
  $variables['tree'] = '';
  if ($book_link['mlid']) {
    $variables['tree'] = book_children($book_link);
    if ($prev = book_prev($book_link)) {
      $prev_href = url($prev['href']);
      drupal_add_html_head_link(array(
        'rel' => 'prev',
        'href' => $prev_href,
      ));
      $variables['prev_url'] = $prev_href;
      $variables['prev_title'] = check_plain($prev['title']);
    }
    if ($book_link['plid'] && ($parent = book_link_load($book_link['plid']))) {
      $parent_href = url($parent['href']);
      drupal_add_html_head_link(array(
        'rel' => 'up',
        'href' => $parent_href,
      ));
      $variables['parent_url'] = $parent_href;
      $variables['parent_title'] = check_plain($parent['title']);
    }
    if ($next = book_next($book_link)) {
      $next_href = url($next['href']);
      drupal_add_html_head_link(array(
        'rel' => 'next',
        'href' => $next_href,
      ));
      $variables['next_url'] = $next_href;
      $variables['next_title'] = check_plain($next['title']);
    }
  }
  $variables['has_links'] = FALSE;

  // Link variables to filter for values and set state of the flag variable.
  $links = array(
    'prev_url',
    'prev_title',
    'parent_url',
    'parent_title',
    'next_url',
    'next_title',
  );
  foreach ($links as $link) {
    if (isset($variables[$link])) {

      // Flag when there is a value.
      $variables['has_links'] = TRUE;
    }
    else {

      // Set empty to prevent notices.
      $variables[$link] = '';
    }
  }
}