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()
75 * @param string $output Passed by reference. Used to append additional content.
76 * @param object $item Menu item data object.
77 * @param int $depth Depth of menu item. Used for padding.
78 * @param array $args An array of arguments. @see wp_nav_menu()
79 * @param int $id Current item ID.
81 public function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {
82 $indent = ( $depth ) ? str_repeat( "\t", $depth ) : '';
84 $classes = empty( $item->classes ) ? array() : (array) $item->classes;
85 $classes[] = 'menu-item-' . $item->ID;
88 * Filter the CSS class(es) applied to a menu item's <li>.
94 * @param array $classes The CSS classes that are applied to the menu item's <li>.
95 * @param object $item The current menu item.
96 * @param array $args An array of wp_nav_menu() arguments.
98 $class_names = join( ' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item, $args ) );
99 $class_names = $class_names ? ' class="' . esc_attr( $class_names ) . '"' : '';
102 * Filter the ID applied to a menu item's <li>.
108 * @param string $menu_id The ID that is applied to the menu item's <li>.
109 * @param object $item The current menu item.
110 * @param array $args An array of wp_nav_menu() arguments.
112 $id = apply_filters( 'nav_menu_item_id', 'menu-item-'. $item->ID, $item, $args );
113 $id = $id ? ' id="' . esc_attr( $id ) . '"' : '';
115 $output .= $indent . '<li' . $id . $class_names .'>';
118 $atts['title'] = ! empty( $item->attr_title ) ? $item->attr_title : '';
119 $atts['target'] = ! empty( $item->target ) ? $item->target : '';
120 $atts['rel'] = ! empty( $item->xfn ) ? $item->xfn : '';
121 $atts['href'] = ! empty( $item->url ) ? $item->url : '';
124 * Filter the HTML attributes applied to a menu item's <a>.
130 * @param array $atts {
131 * The HTML attributes applied to the menu item's <a>, empty strings are ignored.
133 * @type string $title Title attribute.
134 * @type string $target Target attribute.
135 * @type string $rel The rel attribute.
136 * @type string $href The href attribute.
138 * @param object $item The current menu item.
139 * @param array $args An array of wp_nav_menu() arguments.
141 $atts = apply_filters( 'nav_menu_link_attributes', $atts, $item, $args );
144 foreach ( $atts as $attr => $value ) {
145 if ( ! empty( $value ) ) {
146 $value = ( 'href' === $attr ) ? esc_url( $value ) : esc_attr( $value );
147 $attributes .= ' ' . $attr . '="' . $value . '"';
151 $item_output = $args->before;
152 $item_output .= '<a'. $attributes .'>';
153 /** This filter is documented in wp-includes/post-template.php */
154 $item_output .= $args->link_before . apply_filters( 'the_title', $item->title, $item->ID ) . $args->link_after;
155 $item_output .= '</a>';
156 $item_output .= $args->after;
159 * Filter a menu item's starting output.
161 * The menu item's starting output only includes $args->before, the opening <a>,
162 * the menu item's title, the closing </a>, and $args->after. Currently, there is
163 * no filter for modifying the opening and closing <li> for a menu item.
169 * @param string $item_output The menu item's starting HTML output.
170 * @param object $item Menu item data object.
171 * @param int $depth Depth of menu item. Used for padding.
172 * @param array $args An array of wp_nav_menu() arguments.
174 $output .= apply_filters( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );
178 * Ends the element output, if needed.
180 * @see Walker::end_el()
184 * @param string $output Passed by reference. Used to append additional content.
185 * @param object $item Page data object. Not used.
186 * @param int $depth Depth of page. Not Used.
187 * @param array $args An array of arguments. @see wp_nav_menu()
189 public function end_el( &$output, $item, $depth = 0, $args = array() ) {
190 $output .= "</li>\n";
196 * Displays a navigation menu.
200 * @param array $args {
201 * Optional. Array of nav menu arguments.
203 * @type string $menu Desired menu. Accepts (matching in order) id, slug, name. Default empty.
204 * @type string $menu_class CSS class to use for the ul element which forms the menu. Default 'menu'.
205 * @type string $menu_id The ID that is applied to the ul element which forms the menu.
206 * Default is the menu slug, incremented.
207 * @type string $container Whether to wrap the ul, and what to wrap it with. Default 'div'.
208 * @type string $container_class Class that is applied to the container. Default 'menu-{menu slug}-container'.
209 * @type string $container_id The ID that is applied to the container. Default empty.
210 * @type callback|bool $fallback_cb If the menu doesn't exists, a callback function will fire.
211 * Default is 'wp_page_menu'. Set to false for no fallback.
212 * @type string $before Text before the link text. Default empty.
213 * @type string $after Text after the link text. Default empty.
214 * @type string $link_before Text before the link. Default empty.
215 * @type string $link_after Text after the link. Default empty.
216 * @type bool $echo Whether to echo the menu or return it. Default true.
217 * @type int $depth How many levels of the hierarchy are to be included. 0 means all. Default 0.
218 * @type object $walker Instance of a custom walker class. Default empty.
219 * @type string $theme_location Theme location to be used. Must be registered with register_nav_menu()
220 * in order to be selectable by the user.
221 * @type string $items_wrap How the list items should be wrapped. Default is a ul with an id and class.
222 * Uses printf() format with numbered placeholders.
224 * @return mixed Menu output if $echo is false, false if there are no items or no menu was found.
226 function wp_nav_menu( $args = array() ) {
227 static $menu_id_slugs = array();
229 $defaults = array( 'menu' => '', 'container' => 'div', 'container_class' => '', 'container_id' => '', 'menu_class' => 'menu', 'menu_id' => '',
230 'echo' => true, 'fallback_cb' => 'wp_page_menu', 'before' => '', 'after' => '', 'link_before' => '', 'link_after' => '', 'items_wrap' => '<ul id="%1$s" class="%2$s">%3$s</ul>',
231 'depth' => 0, 'walker' => '', 'theme_location' => '' );
233 $args = wp_parse_args( $args, $defaults );
235 * Filter the arguments used to display a navigation menu.
241 * @param array $args Array of wp_nav_menu() arguments.
243 $args = apply_filters( 'wp_nav_menu_args', $args );
244 $args = (object) $args;
247 * Filter whether to short-circuit the wp_nav_menu() output.
249 * Returning a non-null value to the filter will short-circuit
250 * wp_nav_menu(), echoing that value if $args->echo is true,
251 * returning that value otherwise.
257 * @param string|null $output Nav menu output to short-circuit with. Default null.
258 * @param object $args An object containing wp_nav_menu() arguments.
260 $nav_menu = apply_filters( 'pre_wp_nav_menu', null, $args );
262 if ( null !== $nav_menu ) {
271 // Get the nav menu based on the requested menu
272 $menu = wp_get_nav_menu_object( $args->menu );
274 // Get the nav menu based on the theme_location
275 if ( ! $menu && $args->theme_location && ( $locations = get_nav_menu_locations() ) && isset( $locations[ $args->theme_location ] ) )
276 $menu = wp_get_nav_menu_object( $locations[ $args->theme_location ] );
278 // get the first menu that has items if we still can't find a menu
279 if ( ! $menu && !$args->theme_location ) {
280 $menus = wp_get_nav_menus( array( 'orderby' => 'name' ) );
281 foreach ( $menus as $menu_maybe ) {
282 if ( $menu_items = wp_get_nav_menu_items( $menu_maybe->term_id, array( 'update_post_term_cache' => false ) ) ) {
289 // If the menu exists, get its items.
290 if ( $menu && ! is_wp_error($menu) && !isset($menu_items) )
291 $menu_items = wp_get_nav_menu_items( $menu->term_id, array( 'update_post_term_cache' => false ) );
294 * If no menu was found:
295 * - Fall back (if one was specified), or bail.
297 * If no menu items were found:
298 * - Fall back, but only if no theme location was specified.
301 if ( ( !$menu || is_wp_error($menu) || ( isset($menu_items) && empty($menu_items) && !$args->theme_location ) )
302 && $args->fallback_cb && is_callable( $args->fallback_cb ) )
303 return call_user_func( $args->fallback_cb, (array) $args );
305 if ( ! $menu || is_wp_error( $menu ) )
308 $nav_menu = $items = '';
310 $show_container = false;
311 if ( $args->container ) {
313 * Filter the list of HTML tags that are valid for use as menu containers.
317 * @param array $tags The acceptable HTML tags for use as menu containers.
318 * Default is array containing 'div' and 'nav'.
320 $allowed_tags = apply_filters( 'wp_nav_menu_container_allowedtags', array( 'div', 'nav' ) );
321 if ( in_array( $args->container, $allowed_tags ) ) {
322 $show_container = true;
323 $class = $args->container_class ? ' class="' . esc_attr( $args->container_class ) . '"' : ' class="menu-'. $menu->slug .'-container"';
324 $id = $args->container_id ? ' id="' . esc_attr( $args->container_id ) . '"' : '';
325 $nav_menu .= '<'. $args->container . $id . $class . '>';
329 // Set up the $menu_item variables
330 _wp_menu_item_classes_by_context( $menu_items );
332 $sorted_menu_items = $menu_items_with_children = array();
333 foreach ( (array) $menu_items as $menu_item ) {
334 $sorted_menu_items[ $menu_item->menu_order ] = $menu_item;
335 if ( $menu_item->menu_item_parent )
336 $menu_items_with_children[ $menu_item->menu_item_parent ] = true;
339 // Add the menu-item-has-children class where applicable
340 if ( $menu_items_with_children ) {
341 foreach ( $sorted_menu_items as &$menu_item ) {
342 if ( isset( $menu_items_with_children[ $menu_item->ID ] ) )
343 $menu_item->classes[] = 'menu-item-has-children';
347 unset( $menu_items, $menu_item );
350 * Filter the sorted list of menu item objects before generating the menu's HTML.
354 * @param array $sorted_menu_items The menu items, sorted by each menu item's menu order.
355 * @param object $args An object containing wp_nav_menu() arguments.
357 $sorted_menu_items = apply_filters( 'wp_nav_menu_objects', $sorted_menu_items, $args );
359 $items .= walk_nav_menu_tree( $sorted_menu_items, $args->depth, $args );
360 unset($sorted_menu_items);
363 if ( ! empty( $args->menu_id ) ) {
364 $wrap_id = $args->menu_id;
366 $wrap_id = 'menu-' . $menu->slug;
367 while ( in_array( $wrap_id, $menu_id_slugs ) ) {
368 if ( preg_match( '#-(\d+)$#', $wrap_id, $matches ) )
369 $wrap_id = preg_replace('#-(\d+)$#', '-' . ++$matches[1], $wrap_id );
371 $wrap_id = $wrap_id . '-1';
374 $menu_id_slugs[] = $wrap_id;
376 $wrap_class = $args->menu_class ? $args->menu_class : '';
379 * Filter the HTML list content for navigation menus.
385 * @param string $items The HTML list content for the menu items.
386 * @param object $args An object containing wp_nav_menu() arguments.
388 $items = apply_filters( 'wp_nav_menu_items', $items, $args );
390 * Filter the HTML list content for a specific navigation menu.
396 * @param string $items The HTML list content for the menu items.
397 * @param object $args An object containing wp_nav_menu() arguments.
399 $items = apply_filters( "wp_nav_menu_{$menu->slug}_items", $items, $args );
401 // Don't print any markup if there are no items at this point.
402 if ( empty( $items ) )
405 $nav_menu .= sprintf( $args->items_wrap, esc_attr( $wrap_id ), esc_attr( $wrap_class ), $items );
408 if ( $show_container )
409 $nav_menu .= '</' . $args->container . '>';
412 * Filter the HTML content for navigation menus.
418 * @param string $nav_menu The HTML content for the navigation menu.
419 * @param object $args An object containing wp_nav_menu() arguments.
421 $nav_menu = apply_filters( 'wp_nav_menu', $nav_menu, $args );
430 * Add the class property classes for the current context, if applicable.
435 * @param array $menu_items The current menu item objects to which to add the class property information.
437 function _wp_menu_item_classes_by_context( &$menu_items ) {
438 global $wp_query, $wp_rewrite;
440 $queried_object = $wp_query->get_queried_object();
441 $queried_object_id = (int) $wp_query->queried_object_id;
444 $active_ancestor_item_ids = array();
445 $active_parent_item_ids = array();
446 $active_parent_object_ids = array();
447 $possible_taxonomy_ancestors = array();
448 $possible_object_parents = array();
449 $home_page_id = (int) get_option( 'page_for_posts' );
451 if ( $wp_query->is_singular && ! empty( $queried_object->post_type ) && ! is_post_type_hierarchical( $queried_object->post_type ) ) {
452 foreach ( (array) get_object_taxonomies( $queried_object->post_type ) as $taxonomy ) {
453 if ( is_taxonomy_hierarchical( $taxonomy ) ) {
454 $term_hierarchy = _get_term_hierarchy( $taxonomy );
455 $terms = wp_get_object_terms( $queried_object_id, $taxonomy, array( 'fields' => 'ids' ) );
456 if ( is_array( $terms ) ) {
457 $possible_object_parents = array_merge( $possible_object_parents, $terms );
458 $term_to_ancestor = array();
459 foreach ( (array) $term_hierarchy as $anc => $descs ) {
460 foreach ( (array) $descs as $desc )
461 $term_to_ancestor[ $desc ] = $anc;
464 foreach ( $terms as $desc ) {
466 $possible_taxonomy_ancestors[ $taxonomy ][] = $desc;
467 if ( isset( $term_to_ancestor[ $desc ] ) ) {
468 $_desc = $term_to_ancestor[ $desc ];
469 unset( $term_to_ancestor[ $desc ] );
474 } while ( ! empty( $desc ) );
479 } elseif ( ! empty( $queried_object->taxonomy ) && is_taxonomy_hierarchical( $queried_object->taxonomy ) ) {
480 $term_hierarchy = _get_term_hierarchy( $queried_object->taxonomy );
481 $term_to_ancestor = array();
482 foreach ( (array) $term_hierarchy as $anc => $descs ) {
483 foreach ( (array) $descs as $desc )
484 $term_to_ancestor[ $desc ] = $anc;
486 $desc = $queried_object->term_id;
488 $possible_taxonomy_ancestors[ $queried_object->taxonomy ][] = $desc;
489 if ( isset( $term_to_ancestor[ $desc ] ) ) {
490 $_desc = $term_to_ancestor[ $desc ];
491 unset( $term_to_ancestor[ $desc ] );
496 } while ( ! empty( $desc ) );
499 $possible_object_parents = array_filter( $possible_object_parents );
501 $front_page_url = home_url();
503 foreach ( (array) $menu_items as $key => $menu_item ) {
505 $menu_items[$key]->current = false;
507 $classes = (array) $menu_item->classes;
508 $classes[] = 'menu-item';
509 $classes[] = 'menu-item-type-' . $menu_item->type;
510 $classes[] = 'menu-item-object-' . $menu_item->object;
512 // if the menu item corresponds to a taxonomy term for the currently-queried non-hierarchical post object
513 if ( $wp_query->is_singular && 'taxonomy' == $menu_item->type && in_array( $menu_item->object_id, $possible_object_parents ) ) {
514 $active_parent_object_ids[] = (int) $menu_item->object_id;
515 $active_parent_item_ids[] = (int) $menu_item->db_id;
516 $active_object = $queried_object->post_type;
518 // if the menu item corresponds to the currently-queried post or taxonomy object
520 $menu_item->object_id == $queried_object_id &&
522 ( ! empty( $home_page_id ) && 'post_type' == $menu_item->type && $wp_query->is_home && $home_page_id == $menu_item->object_id ) ||
523 ( 'post_type' == $menu_item->type && $wp_query->is_singular ) ||
524 ( 'taxonomy' == $menu_item->type && ( $wp_query->is_category || $wp_query->is_tag || $wp_query->is_tax ) && $queried_object->taxonomy == $menu_item->object )
527 $classes[] = 'current-menu-item';
528 $menu_items[$key]->current = true;
529 $_anc_id = (int) $menu_item->db_id;
532 ( $_anc_id = get_post_meta( $_anc_id, '_menu_item_menu_item_parent', true ) ) &&
533 ! in_array( $_anc_id, $active_ancestor_item_ids )
535 $active_ancestor_item_ids[] = $_anc_id;
538 if ( 'post_type' == $menu_item->type && 'page' == $menu_item->object ) {
539 // Back compat classes for pages to match wp_page_menu()
540 $classes[] = 'page_item';
541 $classes[] = 'page-item-' . $menu_item->object_id;
542 $classes[] = 'current_page_item';
544 $active_parent_item_ids[] = (int) $menu_item->menu_item_parent;
545 $active_parent_object_ids[] = (int) $menu_item->post_parent;
546 $active_object = $menu_item->object;
548 // if the menu item corresponds to the currently-requested URL
549 } elseif ( 'custom' == $menu_item->object ) {
550 $_root_relative_current = untrailingslashit( $_SERVER['REQUEST_URI'] );
551 $current_url = set_url_scheme( 'http://' . $_SERVER['HTTP_HOST'] . $_root_relative_current );
552 $raw_item_url = strpos( $menu_item->url, '#' ) ? substr( $menu_item->url, 0, strpos( $menu_item->url, '#' ) ) : $menu_item->url;
553 $item_url = untrailingslashit( $raw_item_url );
554 $_indexless_current = untrailingslashit( preg_replace( '/' . preg_quote( $wp_rewrite->index, '/' ) . '$/', '', $current_url ) );
556 if ( $raw_item_url && in_array( $item_url, array( $current_url, $_indexless_current, $_root_relative_current ) ) ) {
557 $classes[] = 'current-menu-item';
558 $menu_items[$key]->current = true;
559 $_anc_id = (int) $menu_item->db_id;
562 ( $_anc_id = get_post_meta( $_anc_id, '_menu_item_menu_item_parent', true ) ) &&
563 ! in_array( $_anc_id, $active_ancestor_item_ids )
565 $active_ancestor_item_ids[] = $_anc_id;
568 if ( in_array( home_url(), array( untrailingslashit( $current_url ), untrailingslashit( $_indexless_current ) ) ) ) {
569 // Back compat for home link to match wp_page_menu()
570 $classes[] = 'current_page_item';
572 $active_parent_item_ids[] = (int) $menu_item->menu_item_parent;
573 $active_parent_object_ids[] = (int) $menu_item->post_parent;
574 $active_object = $menu_item->object;
576 // give front page item current-menu-item class when extra query arguments involved
577 } elseif ( $item_url == $front_page_url && is_front_page() ) {
578 $classes[] = 'current-menu-item';
581 if ( untrailingslashit($item_url) == home_url() )
582 $classes[] = 'menu-item-home';
585 // back-compat with wp_page_menu: add "current_page_parent" to static home page link for any non-page query
586 if ( ! empty( $home_page_id ) && 'post_type' == $menu_item->type && empty( $wp_query->is_page ) && $home_page_id == $menu_item->object_id )
587 $classes[] = 'current_page_parent';
589 $menu_items[$key]->classes = array_unique( $classes );
591 $active_ancestor_item_ids = array_filter( array_unique( $active_ancestor_item_ids ) );
592 $active_parent_item_ids = array_filter( array_unique( $active_parent_item_ids ) );
593 $active_parent_object_ids = array_filter( array_unique( $active_parent_object_ids ) );
595 // set parent's class
596 foreach ( (array) $menu_items as $key => $parent_item ) {
597 $classes = (array) $parent_item->classes;
598 $menu_items[$key]->current_item_ancestor = false;
599 $menu_items[$key]->current_item_parent = false;
602 isset( $parent_item->type ) &&
604 // ancestral post object
606 'post_type' == $parent_item->type &&
607 ! empty( $queried_object->post_type ) &&
608 is_post_type_hierarchical( $queried_object->post_type ) &&
609 in_array( $parent_item->object_id, $queried_object->ancestors ) &&
610 $parent_item->object != $queried_object->ID
615 'taxonomy' == $parent_item->type &&
616 isset( $possible_taxonomy_ancestors[ $parent_item->object ] ) &&
617 in_array( $parent_item->object_id, $possible_taxonomy_ancestors[ $parent_item->object ] ) &&
619 ! isset( $queried_object->term_id ) ||
620 $parent_item->object_id != $queried_object->term_id
625 $classes[] = empty( $queried_object->taxonomy ) ? 'current-' . $queried_object->post_type . '-ancestor' : 'current-' . $queried_object->taxonomy . '-ancestor';
628 if ( in_array( intval( $parent_item->db_id ), $active_ancestor_item_ids ) ) {
629 $classes[] = 'current-menu-ancestor';
630 $menu_items[$key]->current_item_ancestor = true;
632 if ( in_array( $parent_item->db_id, $active_parent_item_ids ) ) {
633 $classes[] = 'current-menu-parent';
634 $menu_items[$key]->current_item_parent = true;
636 if ( in_array( $parent_item->object_id, $active_parent_object_ids ) )
637 $classes[] = 'current-' . $active_object . '-parent';
639 if ( 'post_type' == $parent_item->type && 'page' == $parent_item->object ) {
640 // Back compat classes for pages to match wp_page_menu()
641 if ( in_array('current-menu-parent', $classes) )
642 $classes[] = 'current_page_parent';
643 if ( in_array('current-menu-ancestor', $classes) )
644 $classes[] = 'current_page_ancestor';
647 $menu_items[$key]->classes = array_unique( $classes );
652 * Retrieve the HTML list content for nav menu items.
654 * @uses Walker_Nav_Menu to create HTML list content.
656 * @see Walker::walk() for parameters and return description.
658 function walk_nav_menu_tree( $items, $depth, $r ) {
659 $walker = ( empty($r->walker) ) ? new Walker_Nav_Menu : $r->walker;
660 $args = array( $items, $depth, $r );
662 return call_user_func_array( array($walker, 'walk'), $args );
666 * Prevents a menu item ID from being used more than once.
671 function _nav_menu_item_id_use_once( $id, $item ) {
672 static $_used_ids = array();
673 if ( in_array( $item->ID, $_used_ids ) )
675 $_used_ids[] = $item->ID;
678 add_filter( 'nav_menu_item_id', '_nav_menu_item_id_use_once', 10, 2 );