3 * Navigation Menu template functions
6 * @subpackage Nav_Menus
11 * Create HTML list of nav menu items.
16 class Walker_Nav_Menu extends Walker {
18 * What the class handles.
20 * @see Walker::$tree_type
24 public $tree_type = array( 'post_type', 'taxonomy', 'custom' );
27 * Database fields to use.
29 * @see Walker::$db_fields
31 * @todo Decouple this.
34 public $db_fields = array( 'parent' => 'menu_item_parent', 'id' => 'db_id' );
37 * Starts the list before the elements are added.
39 * @see Walker::start_lvl()
43 * @param string $output Passed by reference. Used to append additional content.
44 * @param int $depth Depth of menu item. Used for padding.
45 * @param array $args An array of arguments. @see wp_nav_menu()
47 public function start_lvl( &$output, $depth = 0, $args = array() ) {
48 $indent = str_repeat("\t", $depth);
49 $output .= "\n$indent<ul class=\"sub-menu\">\n";
53 * Ends the list of after the elements are added.
55 * @see Walker::end_lvl()
59 * @param string $output Passed by reference. Used to append additional content.
60 * @param int $depth Depth of menu item. Used for padding.
61 * @param array $args An array of arguments. @see wp_nav_menu()
63 public function end_lvl( &$output, $depth = 0, $args = array() ) {
64 $indent = str_repeat("\t", $depth);
65 $output .= "$indent</ul>\n";
69 * Start the element output.
71 * @see Walker::start_el()
74 * @since 4.4.0 'nav_menu_item_args' filter was added.
76 * @param string $output Passed by reference. Used to append additional content.
77 * @param object $item Menu item data object.
78 * @param int $depth Depth of menu item. Used for padding.
79 * @param array $args An array of arguments. @see wp_nav_menu()
80 * @param int $id Current item ID.
82 public function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {
83 $indent = ( $depth ) ? str_repeat( "\t", $depth ) : '';
85 $classes = empty( $item->classes ) ? array() : (array) $item->classes;
86 $classes[] = 'menu-item-' . $item->ID;
89 * Filter the arguments for a single nav menu item.
93 * @param array $args An array of arguments.
94 * @param object $item Menu item data object.
95 * @param int $depth Depth of menu item. Used for padding.
97 $args = apply_filters( 'nav_menu_item_args', $args, $item, $depth );
100 * Filter the CSS class(es) applied to a menu item's list item element.
103 * @since 4.1.0 The `$depth` parameter was added.
105 * @param array $classes The CSS classes that are applied to the menu item's `<li>` element.
106 * @param object $item The current menu item.
107 * @param array $args An array of {@see wp_nav_menu()} arguments.
108 * @param int $depth Depth of menu item. Used for padding.
110 $class_names = join( ' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item, $args, $depth ) );
111 $class_names = $class_names ? ' class="' . esc_attr( $class_names ) . '"' : '';
114 * Filter the ID applied to a menu item's list item element.
117 * @since 4.1.0 The `$depth` parameter was added.
119 * @param string $menu_id The ID that is applied to the menu item's `<li>` element.
120 * @param object $item The current menu item.
121 * @param array $args An array of {@see wp_nav_menu()} arguments.
122 * @param int $depth Depth of menu item. Used for padding.
124 $id = apply_filters( 'nav_menu_item_id', 'menu-item-'. $item->ID, $item, $args, $depth );
125 $id = $id ? ' id="' . esc_attr( $id ) . '"' : '';
127 $output .= $indent . '<li' . $id . $class_names .'>';
130 $atts['title'] = ! empty( $item->attr_title ) ? $item->attr_title : '';
131 $atts['target'] = ! empty( $item->target ) ? $item->target : '';
132 $atts['rel'] = ! empty( $item->xfn ) ? $item->xfn : '';
133 $atts['href'] = ! empty( $item->url ) ? $item->url : '';
136 * Filter the HTML attributes applied to a menu item's anchor element.
139 * @since 4.1.0 The `$depth` parameter was added.
141 * @param array $atts {
142 * The HTML attributes applied to the menu item's `<a>` element, empty strings are ignored.
144 * @type string $title Title attribute.
145 * @type string $target Target attribute.
146 * @type string $rel The rel attribute.
147 * @type string $href The href attribute.
149 * @param object $item The current menu item.
150 * @param array $args An array of {@see wp_nav_menu()} arguments.
151 * @param int $depth Depth of menu item. Used for padding.
153 $atts = apply_filters( 'nav_menu_link_attributes', $atts, $item, $args, $depth );
156 foreach ( $atts as $attr => $value ) {
157 if ( ! empty( $value ) ) {
158 $value = ( 'href' === $attr ) ? esc_url( $value ) : esc_attr( $value );
159 $attributes .= ' ' . $attr . '="' . $value . '"';
163 /** This filter is documented in wp-includes/post-template.php */
164 $title = apply_filters( 'the_title', $item->title, $item->ID );
167 * Filter a menu item's title.
171 * @param string $title The menu item's title.
172 * @param object $item The current menu item.
173 * @param array $args An array of {@see wp_nav_menu()} arguments.
174 * @param int $depth Depth of menu item. Used for padding.
176 $title = apply_filters( 'nav_menu_item_title', $title, $item, $args, $depth );
178 $item_output = $args->before;
179 $item_output .= '<a'. $attributes .'>';
180 $item_output .= $args->link_before . $title . $args->link_after;
181 $item_output .= '</a>';
182 $item_output .= $args->after;
185 * Filter a menu item's starting output.
187 * The menu item's starting output only includes `$args->before`, the opening `<a>`,
188 * the menu item's title, the closing `</a>`, and `$args->after`. Currently, there is
189 * no filter for modifying the opening and closing `<li>` for a menu item.
193 * @param string $item_output The menu item's starting HTML output.
194 * @param object $item Menu item data object.
195 * @param int $depth Depth of menu item. Used for padding.
196 * @param array $args An array of {@see wp_nav_menu()} arguments.
198 $output .= apply_filters( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );
202 * Ends the element output, if needed.
204 * @see Walker::end_el()
208 * @param string $output Passed by reference. Used to append additional content.
209 * @param object $item Page data object. Not used.
210 * @param int $depth Depth of page. Not Used.
211 * @param array $args An array of arguments. @see wp_nav_menu()
213 public function end_el( &$output, $item, $depth = 0, $args = array() ) {
214 $output .= "</li>\n";
220 * Displays a navigation menu.
224 * @staticvar array $menu_id_slugs
226 * @param array $args {
227 * Optional. Array of nav menu arguments.
229 * @type string $menu Desired menu. Accepts (matching in order) id, slug, name. Default empty.
230 * @type string $menu_class CSS class to use for the ul element which forms the menu. Default 'menu'.
231 * @type string $menu_id The ID that is applied to the ul element which forms the menu.
232 * Default is the menu slug, incremented.
233 * @type string $container Whether to wrap the ul, and what to wrap it with. Default 'div'.
234 * @type string $container_class Class that is applied to the container. Default 'menu-{menu slug}-container'.
235 * @type string $container_id The ID that is applied to the container. Default empty.
236 * @type callable|bool $fallback_cb If the menu doesn't exists, a callback function will fire.
237 * Default is 'wp_page_menu'. Set to false for no fallback.
238 * @type string $before Text before the link text. Default empty.
239 * @type string $after Text after the link text. Default empty.
240 * @type string $link_before Text before the link. Default empty.
241 * @type string $link_after Text after the link. Default empty.
242 * @type bool $echo Whether to echo the menu or return it. Default true.
243 * @type int $depth How many levels of the hierarchy are to be included. 0 means all. Default 0.
244 * @type object $walker Instance of a custom walker class. Default empty.
245 * @type string $theme_location Theme location to be used. Must be registered with register_nav_menu()
246 * in order to be selectable by the user.
247 * @type string $items_wrap How the list items should be wrapped. Default is a ul with an id and class.
248 * Uses printf() format with numbered placeholders.
250 * @return object|false|void Menu output if $echo is false, false if there are no items or no menu was found.
252 function wp_nav_menu( $args = array() ) {
253 static $menu_id_slugs = array();
255 $defaults = array( 'menu' => '', 'container' => 'div', 'container_class' => '', 'container_id' => '', 'menu_class' => 'menu', 'menu_id' => '',
256 'echo' => true, 'fallback_cb' => 'wp_page_menu', 'before' => '', 'after' => '', 'link_before' => '', 'link_after' => '', 'items_wrap' => '<ul id="%1$s" class="%2$s">%3$s</ul>',
257 'depth' => 0, 'walker' => '', 'theme_location' => '' );
259 $args = wp_parse_args( $args, $defaults );
261 * Filter the arguments used to display a navigation menu.
267 * @param array $args Array of wp_nav_menu() arguments.
269 $args = apply_filters( 'wp_nav_menu_args', $args );
270 $args = (object) $args;
273 * Filter whether to short-circuit the wp_nav_menu() output.
275 * Returning a non-null value to the filter will short-circuit
276 * wp_nav_menu(), echoing that value if $args->echo is true,
277 * returning that value otherwise.
283 * @param string|null $output Nav menu output to short-circuit with. Default null.
284 * @param object $args An object containing wp_nav_menu() arguments.
286 $nav_menu = apply_filters( 'pre_wp_nav_menu', null, $args );
288 if ( null !== $nav_menu ) {
297 // Get the nav menu based on the requested menu
298 $menu = wp_get_nav_menu_object( $args->menu );
300 // Get the nav menu based on the theme_location
301 if ( ! $menu && $args->theme_location && ( $locations = get_nav_menu_locations() ) && isset( $locations[ $args->theme_location ] ) )
302 $menu = wp_get_nav_menu_object( $locations[ $args->theme_location ] );
304 // get the first menu that has items if we still can't find a menu
305 if ( ! $menu && !$args->theme_location ) {
306 $menus = wp_get_nav_menus();
307 foreach ( $menus as $menu_maybe ) {
308 if ( $menu_items = wp_get_nav_menu_items( $menu_maybe->term_id, array( 'update_post_term_cache' => false ) ) ) {
315 if ( empty( $args->menu ) ) {
319 // If the menu exists, get its items.
320 if ( $menu && ! is_wp_error($menu) && !isset($menu_items) )
321 $menu_items = wp_get_nav_menu_items( $menu->term_id, array( 'update_post_term_cache' => false ) );
324 * If no menu was found:
325 * - Fall back (if one was specified), or bail.
327 * If no menu items were found:
328 * - Fall back, but only if no theme location was specified.
331 if ( ( !$menu || is_wp_error($menu) || ( isset($menu_items) && empty($menu_items) && !$args->theme_location ) )
332 && isset( $args->fallback_cb ) && $args->fallback_cb && is_callable( $args->fallback_cb ) )
333 return call_user_func( $args->fallback_cb, (array) $args );
335 if ( ! $menu || is_wp_error( $menu ) )
338 $nav_menu = $items = '';
340 $show_container = false;
341 if ( $args->container ) {
343 * Filter the list of HTML tags that are valid for use as menu containers.
347 * @param array $tags The acceptable HTML tags for use as menu containers.
348 * Default is array containing 'div' and 'nav'.
350 $allowed_tags = apply_filters( 'wp_nav_menu_container_allowedtags', array( 'div', 'nav' ) );
351 if ( is_string( $args->container ) && in_array( $args->container, $allowed_tags ) ) {
352 $show_container = true;
353 $class = $args->container_class ? ' class="' . esc_attr( $args->container_class ) . '"' : ' class="menu-'. $menu->slug .'-container"';
354 $id = $args->container_id ? ' id="' . esc_attr( $args->container_id ) . '"' : '';
355 $nav_menu .= '<'. $args->container . $id . $class . '>';
359 // Set up the $menu_item variables
360 _wp_menu_item_classes_by_context( $menu_items );
362 $sorted_menu_items = $menu_items_with_children = array();
363 foreach ( (array) $menu_items as $menu_item ) {
364 $sorted_menu_items[ $menu_item->menu_order ] = $menu_item;
365 if ( $menu_item->menu_item_parent )
366 $menu_items_with_children[ $menu_item->menu_item_parent ] = true;
369 // Add the menu-item-has-children class where applicable
370 if ( $menu_items_with_children ) {
371 foreach ( $sorted_menu_items as &$menu_item ) {
372 if ( isset( $menu_items_with_children[ $menu_item->ID ] ) )
373 $menu_item->classes[] = 'menu-item-has-children';
377 unset( $menu_items, $menu_item );
380 * Filter the sorted list of menu item objects before generating the menu's HTML.
384 * @param array $sorted_menu_items The menu items, sorted by each menu item's menu order.
385 * @param object $args An object containing wp_nav_menu() arguments.
387 $sorted_menu_items = apply_filters( 'wp_nav_menu_objects', $sorted_menu_items, $args );
389 $items .= walk_nav_menu_tree( $sorted_menu_items, $args->depth, $args );
390 unset($sorted_menu_items);
393 if ( ! empty( $args->menu_id ) ) {
394 $wrap_id = $args->menu_id;
396 $wrap_id = 'menu-' . $menu->slug;
397 while ( in_array( $wrap_id, $menu_id_slugs ) ) {
398 if ( preg_match( '#-(\d+)$#', $wrap_id, $matches ) )
399 $wrap_id = preg_replace('#-(\d+)$#', '-' . ++$matches[1], $wrap_id );
401 $wrap_id = $wrap_id . '-1';
404 $menu_id_slugs[] = $wrap_id;
406 $wrap_class = $args->menu_class ? $args->menu_class : '';
409 * Filter the HTML list content for navigation menus.
415 * @param string $items The HTML list content for the menu items.
416 * @param object $args An object containing wp_nav_menu() arguments.
418 $items = apply_filters( 'wp_nav_menu_items', $items, $args );
420 * Filter the HTML list content for a specific navigation menu.
426 * @param string $items The HTML list content for the menu items.
427 * @param object $args An object containing wp_nav_menu() arguments.
429 $items = apply_filters( "wp_nav_menu_{$menu->slug}_items", $items, $args );
431 // Don't print any markup if there are no items at this point.
432 if ( empty( $items ) )
435 $nav_menu .= sprintf( $args->items_wrap, esc_attr( $wrap_id ), esc_attr( $wrap_class ), $items );
438 if ( $show_container )
439 $nav_menu .= '</' . $args->container . '>';
442 * Filter the HTML content for navigation menus.
448 * @param string $nav_menu The HTML content for the navigation menu.
449 * @param object $args An object containing wp_nav_menu() arguments.
451 $nav_menu = apply_filters( 'wp_nav_menu', $nav_menu, $args );
460 * Add the class property classes for the current context, if applicable.
465 * @global WP_Query $wp_query
466 * @global WP_Rewrite $wp_rewrite
468 * @param array $menu_items The current menu item objects to which to add the class property information.
470 function _wp_menu_item_classes_by_context( &$menu_items ) {
471 global $wp_query, $wp_rewrite;
473 $queried_object = $wp_query->get_queried_object();
474 $queried_object_id = (int) $wp_query->queried_object_id;
477 $active_ancestor_item_ids = array();
478 $active_parent_item_ids = array();
479 $active_parent_object_ids = array();
480 $possible_taxonomy_ancestors = array();
481 $possible_object_parents = array();
482 $home_page_id = (int) get_option( 'page_for_posts' );
484 if ( $wp_query->is_singular && ! empty( $queried_object->post_type ) && ! is_post_type_hierarchical( $queried_object->post_type ) ) {
485 foreach ( (array) get_object_taxonomies( $queried_object->post_type ) as $taxonomy ) {
486 if ( is_taxonomy_hierarchical( $taxonomy ) ) {
487 $term_hierarchy = _get_term_hierarchy( $taxonomy );
488 $terms = wp_get_object_terms( $queried_object_id, $taxonomy, array( 'fields' => 'ids' ) );
489 if ( is_array( $terms ) ) {
490 $possible_object_parents = array_merge( $possible_object_parents, $terms );
491 $term_to_ancestor = array();
492 foreach ( (array) $term_hierarchy as $anc => $descs ) {
493 foreach ( (array) $descs as $desc )
494 $term_to_ancestor[ $desc ] = $anc;
497 foreach ( $terms as $desc ) {
499 $possible_taxonomy_ancestors[ $taxonomy ][] = $desc;
500 if ( isset( $term_to_ancestor[ $desc ] ) ) {
501 $_desc = $term_to_ancestor[ $desc ];
502 unset( $term_to_ancestor[ $desc ] );
507 } while ( ! empty( $desc ) );
512 } elseif ( ! empty( $queried_object->taxonomy ) && is_taxonomy_hierarchical( $queried_object->taxonomy ) ) {
513 $term_hierarchy = _get_term_hierarchy( $queried_object->taxonomy );
514 $term_to_ancestor = array();
515 foreach ( (array) $term_hierarchy as $anc => $descs ) {
516 foreach ( (array) $descs as $desc )
517 $term_to_ancestor[ $desc ] = $anc;
519 $desc = $queried_object->term_id;
521 $possible_taxonomy_ancestors[ $queried_object->taxonomy ][] = $desc;
522 if ( isset( $term_to_ancestor[ $desc ] ) ) {
523 $_desc = $term_to_ancestor[ $desc ];
524 unset( $term_to_ancestor[ $desc ] );
529 } while ( ! empty( $desc ) );
532 $possible_object_parents = array_filter( $possible_object_parents );
534 $front_page_url = home_url();
536 foreach ( (array) $menu_items as $key => $menu_item ) {
538 $menu_items[$key]->current = false;
540 $classes = (array) $menu_item->classes;
541 $classes[] = 'menu-item';
542 $classes[] = 'menu-item-type-' . $menu_item->type;
543 $classes[] = 'menu-item-object-' . $menu_item->object;
545 // if the menu item corresponds to a taxonomy term for the currently-queried non-hierarchical post object
546 if ( $wp_query->is_singular && 'taxonomy' == $menu_item->type && in_array( $menu_item->object_id, $possible_object_parents ) ) {
547 $active_parent_object_ids[] = (int) $menu_item->object_id;
548 $active_parent_item_ids[] = (int) $menu_item->db_id;
549 $active_object = $queried_object->post_type;
551 // if the menu item corresponds to the currently-queried post or taxonomy object
553 $menu_item->object_id == $queried_object_id &&
555 ( ! empty( $home_page_id ) && 'post_type' == $menu_item->type && $wp_query->is_home && $home_page_id == $menu_item->object_id ) ||
556 ( 'post_type' == $menu_item->type && $wp_query->is_singular ) ||
557 ( 'taxonomy' == $menu_item->type && ( $wp_query->is_category || $wp_query->is_tag || $wp_query->is_tax ) && $queried_object->taxonomy == $menu_item->object )
560 $classes[] = 'current-menu-item';
561 $menu_items[$key]->current = true;
562 $_anc_id = (int) $menu_item->db_id;
565 ( $_anc_id = get_post_meta( $_anc_id, '_menu_item_menu_item_parent', true ) ) &&
566 ! in_array( $_anc_id, $active_ancestor_item_ids )
568 $active_ancestor_item_ids[] = $_anc_id;
571 if ( 'post_type' == $menu_item->type && 'page' == $menu_item->object ) {
572 // Back compat classes for pages to match wp_page_menu()
573 $classes[] = 'page_item';
574 $classes[] = 'page-item-' . $menu_item->object_id;
575 $classes[] = 'current_page_item';
577 $active_parent_item_ids[] = (int) $menu_item->menu_item_parent;
578 $active_parent_object_ids[] = (int) $menu_item->post_parent;
579 $active_object = $menu_item->object;
581 // if the menu item corresponds to the currently-queried post type archive
583 'post_type_archive' == $menu_item->type &&
584 is_post_type_archive( array( $menu_item->object ) )
586 $classes[] = 'current-menu-item';
587 $menu_items[$key]->current = true;
588 // if the menu item corresponds to the currently-requested URL
589 } elseif ( 'custom' == $menu_item->object && isset( $_SERVER['HTTP_HOST'] ) ) {
590 $_root_relative_current = untrailingslashit( $_SERVER['REQUEST_URI'] );
591 $current_url = set_url_scheme( 'http://' . $_SERVER['HTTP_HOST'] . $_root_relative_current );
592 $raw_item_url = strpos( $menu_item->url, '#' ) ? substr( $menu_item->url, 0, strpos( $menu_item->url, '#' ) ) : $menu_item->url;
593 $item_url = set_url_scheme( untrailingslashit( $raw_item_url ) );
594 $_indexless_current = untrailingslashit( preg_replace( '/' . preg_quote( $wp_rewrite->index, '/' ) . '$/', '', $current_url ) );
596 if ( $raw_item_url && in_array( $item_url, array( $current_url, $_indexless_current, $_root_relative_current ) ) ) {
597 $classes[] = 'current-menu-item';
598 $menu_items[$key]->current = true;
599 $_anc_id = (int) $menu_item->db_id;
602 ( $_anc_id = get_post_meta( $_anc_id, '_menu_item_menu_item_parent', true ) ) &&
603 ! in_array( $_anc_id, $active_ancestor_item_ids )
605 $active_ancestor_item_ids[] = $_anc_id;
608 if ( in_array( home_url(), array( untrailingslashit( $current_url ), untrailingslashit( $_indexless_current ) ) ) ) {
609 // Back compat for home link to match wp_page_menu()
610 $classes[] = 'current_page_item';
612 $active_parent_item_ids[] = (int) $menu_item->menu_item_parent;
613 $active_parent_object_ids[] = (int) $menu_item->post_parent;
614 $active_object = $menu_item->object;
616 // give front page item current-menu-item class when extra query arguments involved
617 } elseif ( $item_url == $front_page_url && is_front_page() ) {
618 $classes[] = 'current-menu-item';
621 if ( untrailingslashit($item_url) == home_url() )
622 $classes[] = 'menu-item-home';
625 // back-compat with wp_page_menu: add "current_page_parent" to static home page link for any non-page query
626 if ( ! empty( $home_page_id ) && 'post_type' == $menu_item->type && empty( $wp_query->is_page ) && $home_page_id == $menu_item->object_id )
627 $classes[] = 'current_page_parent';
629 $menu_items[$key]->classes = array_unique( $classes );
631 $active_ancestor_item_ids = array_filter( array_unique( $active_ancestor_item_ids ) );
632 $active_parent_item_ids = array_filter( array_unique( $active_parent_item_ids ) );
633 $active_parent_object_ids = array_filter( array_unique( $active_parent_object_ids ) );
635 // set parent's class
636 foreach ( (array) $menu_items as $key => $parent_item ) {
637 $classes = (array) $parent_item->classes;
638 $menu_items[$key]->current_item_ancestor = false;
639 $menu_items[$key]->current_item_parent = false;
642 isset( $parent_item->type ) &&
644 // ancestral post object
646 'post_type' == $parent_item->type &&
647 ! empty( $queried_object->post_type ) &&
648 is_post_type_hierarchical( $queried_object->post_type ) &&
649 in_array( $parent_item->object_id, $queried_object->ancestors ) &&
650 $parent_item->object != $queried_object->ID
655 'taxonomy' == $parent_item->type &&
656 isset( $possible_taxonomy_ancestors[ $parent_item->object ] ) &&
657 in_array( $parent_item->object_id, $possible_taxonomy_ancestors[ $parent_item->object ] ) &&
659 ! isset( $queried_object->term_id ) ||
660 $parent_item->object_id != $queried_object->term_id
665 $classes[] = empty( $queried_object->taxonomy ) ? 'current-' . $queried_object->post_type . '-ancestor' : 'current-' . $queried_object->taxonomy . '-ancestor';
668 if ( in_array( intval( $parent_item->db_id ), $active_ancestor_item_ids ) ) {
669 $classes[] = 'current-menu-ancestor';
670 $menu_items[$key]->current_item_ancestor = true;
672 if ( in_array( $parent_item->db_id, $active_parent_item_ids ) ) {
673 $classes[] = 'current-menu-parent';
674 $menu_items[$key]->current_item_parent = true;
676 if ( in_array( $parent_item->object_id, $active_parent_object_ids ) )
677 $classes[] = 'current-' . $active_object . '-parent';
679 if ( 'post_type' == $parent_item->type && 'page' == $parent_item->object ) {
680 // Back compat classes for pages to match wp_page_menu()
681 if ( in_array('current-menu-parent', $classes) )
682 $classes[] = 'current_page_parent';
683 if ( in_array('current-menu-ancestor', $classes) )
684 $classes[] = 'current_page_ancestor';
687 $menu_items[$key]->classes = array_unique( $classes );
692 * Retrieve the HTML list content for nav menu items.
694 * @uses Walker_Nav_Menu to create HTML list content.
697 * @param array $items
702 function walk_nav_menu_tree( $items, $depth, $r ) {
703 $walker = ( empty($r->walker) ) ? new Walker_Nav_Menu : $r->walker;
704 $args = array( $items, $depth, $r );
706 return call_user_func_array( array( $walker, 'walk' ), $args );
710 * Prevents a menu item ID from being used more than once.
715 * @staticvar array $used_ids
717 * @param object $item
720 function _nav_menu_item_id_use_once( $id, $item ) {
721 static $_used_ids = array();
722 if ( in_array( $item->ID, $_used_ids ) ) {
725 $_used_ids[] = $item->ID;