3 * Navigation Menu template functions
6 * @subpackage Nav_Menus
11 * Create HTML list of nav menu items.
17 class Walker_Nav_Menu extends Walker {
19 * What the class handles.
21 * @see Walker::$tree_type
25 var $tree_type = array( 'post_type', 'taxonomy', 'custom' );
28 * Database fields to use.
30 * @see Walker::$db_fields
32 * @todo Decouple this.
35 var $db_fields = array( 'parent' => 'menu_item_parent', 'id' => 'db_id' );
38 * Starts the list before the elements are added.
40 * @see Walker::start_lvl()
44 * @param string $output Passed by reference. Used to append additional content.
45 * @param int $depth Depth of menu item. Used for padding.
46 * @param array $args An array of arguments. @see wp_nav_menu()
48 function start_lvl( &$output, $depth = 0, $args = array() ) {
49 $indent = str_repeat("\t", $depth);
50 $output .= "\n$indent<ul class=\"sub-menu\">\n";
54 * Ends the list of after the elements are added.
56 * @see Walker::end_lvl()
60 * @param string $output Passed by reference. Used to append additional content.
61 * @param int $depth Depth of menu item. Used for padding.
62 * @param array $args An array of arguments. @see wp_nav_menu()
64 function end_lvl( &$output, $depth = 0, $args = array() ) {
65 $indent = str_repeat("\t", $depth);
66 $output .= "$indent</ul>\n";
70 * Start the element output.
72 * @see Walker::start_el()
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 $id Current item ID.
82 function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {
83 $indent = ( $depth ) ? str_repeat( "\t", $depth ) : '';
85 $class_names = $value = '';
87 $classes = empty( $item->classes ) ? array() : (array) $item->classes;
88 $classes[] = 'menu-item-' . $item->ID;
91 * Filter the CSS class(es) applied to a menu item's <li>.
95 * @param array $classes The CSS classes that are applied to the menu item's <li>.
96 * @param object $item The current menu item.
97 * @param array $args An array of arguments. @see wp_nav_menu()
99 $class_names = join( ' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item, $args ) );
100 $class_names = $class_names ? ' class="' . esc_attr( $class_names ) . '"' : '';
103 * Filter the ID applied to a menu item's <li>.
107 * @param string The ID that is applied to the menu item's <li>.
108 * @param object $item The current menu item.
109 * @param array $args An array of arguments. @see wp_nav_menu()
111 $id = apply_filters( 'nav_menu_item_id', 'menu-item-'. $item->ID, $item, $args );
112 $id = $id ? ' id="' . esc_attr( $id ) . '"' : '';
114 $output .= $indent . '<li' . $id . $value . $class_names .'>';
117 $atts['title'] = ! empty( $item->attr_title ) ? $item->attr_title : '';
118 $atts['target'] = ! empty( $item->target ) ? $item->target : '';
119 $atts['rel'] = ! empty( $item->xfn ) ? $item->xfn : '';
120 $atts['href'] = ! empty( $item->url ) ? $item->url : '';
123 * Filter the HTML attributes applied to a menu item's <a>.
127 * @param array $atts {
128 * The HTML attributes applied to the menu item's <a>, empty strings are ignored.
130 * @type string $title The title attribute.
131 * @type string $target The target attribute.
132 * @type string $rel The rel attribute.
133 * @type string $href The href attribute.
135 * @param object $item The current menu item.
136 * @param array $args An array of arguments. @see wp_nav_menu()
138 $atts = apply_filters( 'nav_menu_link_attributes', $atts, $item, $args );
141 foreach ( $atts as $attr => $value ) {
142 if ( ! empty( $value ) ) {
143 $value = ( 'href' === $attr ) ? esc_url( $value ) : esc_attr( $value );
144 $attributes .= ' ' . $attr . '="' . $value . '"';
148 $item_output = $args->before;
149 $item_output .= '<a'. $attributes .'>';
150 /** This filter is documented in wp-includes/post-template.php */
151 $item_output .= $args->link_before . apply_filters( 'the_title', $item->title, $item->ID ) . $args->link_after;
152 $item_output .= '</a>';
153 $item_output .= $args->after;
156 * Filter a menu item's starting output.
158 * The menu item's starting output only includes $args->before, the opening <a>,
159 * the menu item's title, the closing </a>, and $args->after. Currently, there is
160 * no filter for modifying the opening and closing <li> for a menu item.
164 * @param string $item_output The menu item's starting HTML output.
165 * @param object $item Menu item data object.
166 * @param int $depth Depth of menu item. Used for padding.
167 * @param array $args An array of arguments. @see wp_nav_menu()
169 $output .= apply_filters( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );
173 * Ends the element output, if needed.
175 * @see Walker::end_el()
179 * @param string $output Passed by reference. Used to append additional content.
180 * @param object $item Page data object. Not used.
181 * @param int $depth Depth of page. Not Used.
182 * @param array $args An array of arguments. @see wp_nav_menu()
184 function end_el( &$output, $item, $depth = 0, $args = array() ) {
185 $output .= "</li>\n";
191 * Displays a navigation menu.
193 * Optional $args contents:
195 * menu - The menu that is desired. Accepts (matching in order) id, slug, name. Defaults to blank.
196 * menu_class - CSS class to use for the ul element which forms the menu. Defaults to 'menu'.
197 * menu_id - The ID that is applied to the ul element which forms the menu. Defaults to the menu slug, incremented.
198 * container - Whether to wrap the ul, and what to wrap it with. Defaults to 'div'.
199 * container_class - the class that is applied to the container. Defaults to 'menu-{menu slug}-container'.
200 * container_id - The ID that is applied to the container. Defaults to blank.
201 * fallback_cb - If the menu doesn't exists, a callback function will fire. Defaults to 'wp_page_menu'. Set to false for no fallback.
202 * before - Text before the link text.
203 * after - Text after the link text.
204 * link_before - Text before the link.
205 * link_after - Text after the link.
206 * echo - Whether to echo the menu or return it. Defaults to echo.
207 * depth - how many levels of the hierarchy are to be included. 0 means all. Defaults to 0.
208 * walker - allows a custom walker to be specified.
209 * theme_location - the location in the theme to be used. Must be registered with register_nav_menu() in order to be selectable by the user.
210 * items_wrap - How the list items should be wrapped. Defaults to a ul with an id and class. Uses printf() format with numbered placeholders.
214 * @param array $args Arguments
216 function wp_nav_menu( $args = array() ) {
217 static $menu_id_slugs = array();
219 $defaults = array( 'menu' => '', 'container' => 'div', 'container_class' => '', 'container_id' => '', 'menu_class' => 'menu', 'menu_id' => '',
220 'echo' => true, 'fallback_cb' => 'wp_page_menu', 'before' => '', 'after' => '', 'link_before' => '', 'link_after' => '', 'items_wrap' => '<ul id="%1$s" class="%2$s">%3$s</ul>',
221 'depth' => 0, 'walker' => '', 'theme_location' => '' );
223 $args = wp_parse_args( $args, $defaults );
225 * Filter the arguments used to display a navigation menu.
229 * @param array $args Arguments from {@see wp_nav_menu()}.
231 $args = apply_filters( 'wp_nav_menu_args', $args );
232 $args = (object) $args;
234 // Get the nav menu based on the requested menu
235 $menu = wp_get_nav_menu_object( $args->menu );
237 // Get the nav menu based on the theme_location
238 if ( ! $menu && $args->theme_location && ( $locations = get_nav_menu_locations() ) && isset( $locations[ $args->theme_location ] ) )
239 $menu = wp_get_nav_menu_object( $locations[ $args->theme_location ] );
241 // get the first menu that has items if we still can't find a menu
242 if ( ! $menu && !$args->theme_location ) {
243 $menus = wp_get_nav_menus();
244 foreach ( $menus as $menu_maybe ) {
245 if ( $menu_items = wp_get_nav_menu_items( $menu_maybe->term_id, array( 'update_post_term_cache' => false ) ) ) {
252 // If the menu exists, get its items.
253 if ( $menu && ! is_wp_error($menu) && !isset($menu_items) )
254 $menu_items = wp_get_nav_menu_items( $menu->term_id, array( 'update_post_term_cache' => false ) );
257 * If no menu was found:
258 * - Fall back (if one was specified), or bail.
260 * If no menu items were found:
261 * - Fall back, but only if no theme location was specified.
264 if ( ( !$menu || is_wp_error($menu) || ( isset($menu_items) && empty($menu_items) && !$args->theme_location ) )
265 && $args->fallback_cb && is_callable( $args->fallback_cb ) )
266 return call_user_func( $args->fallback_cb, (array) $args );
268 if ( ! $menu || is_wp_error( $menu ) )
271 $nav_menu = $items = '';
273 $show_container = false;
274 if ( $args->container ) {
276 * Filter the list of HTML tags that are valid for use as menu containers.
280 * @param array The acceptable HTML tags for use as menu containers, defaults as 'div' and 'nav'.
282 $allowed_tags = apply_filters( 'wp_nav_menu_container_allowedtags', array( 'div', 'nav' ) );
283 if ( in_array( $args->container, $allowed_tags ) ) {
284 $show_container = true;
285 $class = $args->container_class ? ' class="' . esc_attr( $args->container_class ) . '"' : ' class="menu-'. $menu->slug .'-container"';
286 $id = $args->container_id ? ' id="' . esc_attr( $args->container_id ) . '"' : '';
287 $nav_menu .= '<'. $args->container . $id . $class . '>';
291 // Set up the $menu_item variables
292 _wp_menu_item_classes_by_context( $menu_items );
294 $sorted_menu_items = $menu_items_with_children = array();
295 foreach ( (array) $menu_items as $menu_item ) {
296 $sorted_menu_items[ $menu_item->menu_order ] = $menu_item;
297 if ( $menu_item->menu_item_parent )
298 $menu_items_with_children[ $menu_item->menu_item_parent ] = true;
301 // Add the menu-item-has-children class where applicable
302 if ( $menu_items_with_children ) {
303 foreach ( $sorted_menu_items as &$menu_item ) {
304 if ( isset( $menu_items_with_children[ $menu_item->ID ] ) )
305 $menu_item->classes[] = 'menu-item-has-children';
309 unset( $menu_items, $menu_item );
312 * Filter the sorted list of menu item objects before generating the menu's HTML.
316 * @param array $sorted_menu_items The menu items, sorted by each menu item's menu order.
318 $sorted_menu_items = apply_filters( 'wp_nav_menu_objects', $sorted_menu_items, $args );
320 $items .= walk_nav_menu_tree( $sorted_menu_items, $args->depth, $args );
321 unset($sorted_menu_items);
324 if ( ! empty( $args->menu_id ) ) {
325 $wrap_id = $args->menu_id;
327 $wrap_id = 'menu-' . $menu->slug;
328 while ( in_array( $wrap_id, $menu_id_slugs ) ) {
329 if ( preg_match( '#-(\d+)$#', $wrap_id, $matches ) )
330 $wrap_id = preg_replace('#-(\d+)$#', '-' . ++$matches[1], $wrap_id );
332 $wrap_id = $wrap_id . '-1';
335 $menu_id_slugs[] = $wrap_id;
337 $wrap_class = $args->menu_class ? $args->menu_class : '';
340 * Filter the HTML list content for navigation menus.
344 * @param string $items The HTML list content for the menu items.
345 * @param array $args Arguments from {@see wp_nav_menu()}.
347 $items = apply_filters( 'wp_nav_menu_items', $items, $args );
349 * Filter the HTML list content for a specific navigation menu.
353 * @param string $items The HTML list content for the menu items.
354 * @param array $args Arguments from {@see wp_nav_menu()}.
356 $items = apply_filters( "wp_nav_menu_{$menu->slug}_items", $items, $args );
358 // Don't print any markup if there are no items at this point.
359 if ( empty( $items ) )
362 $nav_menu .= sprintf( $args->items_wrap, esc_attr( $wrap_id ), esc_attr( $wrap_class ), $items );
365 if ( $show_container )
366 $nav_menu .= '</' . $args->container . '>';
369 * Filter the HTML content for navigation menus.
373 * @param string $nav_menu The HTML content for the navigation menu.
374 * @param array $args Arguments from {@see wp_nav_menu()}.
376 $nav_menu = apply_filters( 'wp_nav_menu', $nav_menu, $args );
385 * Add the class property classes for the current context, if applicable.
390 * @param array $menu_items The current menu item objects to which to add the class property information.
392 function _wp_menu_item_classes_by_context( &$menu_items ) {
393 global $wp_query, $wp_rewrite;
395 $queried_object = $wp_query->get_queried_object();
396 $queried_object_id = (int) $wp_query->queried_object_id;
399 $active_ancestor_item_ids = array();
400 $active_parent_item_ids = array();
401 $active_parent_object_ids = array();
402 $possible_taxonomy_ancestors = array();
403 $possible_object_parents = array();
404 $home_page_id = (int) get_option( 'page_for_posts' );
406 if ( $wp_query->is_singular && ! empty( $queried_object->post_type ) && ! is_post_type_hierarchical( $queried_object->post_type ) ) {
407 foreach ( (array) get_object_taxonomies( $queried_object->post_type ) as $taxonomy ) {
408 if ( is_taxonomy_hierarchical( $taxonomy ) ) {
409 $term_hierarchy = _get_term_hierarchy( $taxonomy );
410 $terms = wp_get_object_terms( $queried_object_id, $taxonomy, array( 'fields' => 'ids' ) );
411 if ( is_array( $terms ) ) {
412 $possible_object_parents = array_merge( $possible_object_parents, $terms );
413 $term_to_ancestor = array();
414 foreach ( (array) $term_hierarchy as $anc => $descs ) {
415 foreach ( (array) $descs as $desc )
416 $term_to_ancestor[ $desc ] = $anc;
419 foreach ( $terms as $desc ) {
421 $possible_taxonomy_ancestors[ $taxonomy ][] = $desc;
422 if ( isset( $term_to_ancestor[ $desc ] ) ) {
423 $_desc = $term_to_ancestor[ $desc ];
424 unset( $term_to_ancestor[ $desc ] );
429 } while ( ! empty( $desc ) );
434 } elseif ( ! empty( $queried_object->taxonomy ) && is_taxonomy_hierarchical( $queried_object->taxonomy ) ) {
435 $term_hierarchy = _get_term_hierarchy( $queried_object->taxonomy );
436 $term_to_ancestor = array();
437 foreach ( (array) $term_hierarchy as $anc => $descs ) {
438 foreach ( (array) $descs as $desc )
439 $term_to_ancestor[ $desc ] = $anc;
441 $desc = $queried_object->term_id;
443 $possible_taxonomy_ancestors[ $queried_object->taxonomy ][] = $desc;
444 if ( isset( $term_to_ancestor[ $desc ] ) ) {
445 $_desc = $term_to_ancestor[ $desc ];
446 unset( $term_to_ancestor[ $desc ] );
451 } while ( ! empty( $desc ) );
454 $possible_object_parents = array_filter( $possible_object_parents );
456 $front_page_url = home_url();
458 foreach ( (array) $menu_items as $key => $menu_item ) {
460 $menu_items[$key]->current = false;
462 $classes = (array) $menu_item->classes;
463 $classes[] = 'menu-item';
464 $classes[] = 'menu-item-type-' . $menu_item->type;
465 $classes[] = 'menu-item-object-' . $menu_item->object;
467 // if the menu item corresponds to a taxonomy term for the currently-queried non-hierarchical post object
468 if ( $wp_query->is_singular && 'taxonomy' == $menu_item->type && in_array( $menu_item->object_id, $possible_object_parents ) ) {
469 $active_parent_object_ids[] = (int) $menu_item->object_id;
470 $active_parent_item_ids[] = (int) $menu_item->db_id;
471 $active_object = $queried_object->post_type;
473 // if the menu item corresponds to the currently-queried post or taxonomy object
475 $menu_item->object_id == $queried_object_id &&
477 ( ! empty( $home_page_id ) && 'post_type' == $menu_item->type && $wp_query->is_home && $home_page_id == $menu_item->object_id ) ||
478 ( 'post_type' == $menu_item->type && $wp_query->is_singular ) ||
479 ( 'taxonomy' == $menu_item->type && ( $wp_query->is_category || $wp_query->is_tag || $wp_query->is_tax ) && $queried_object->taxonomy == $menu_item->object )
482 $classes[] = 'current-menu-item';
483 $menu_items[$key]->current = true;
484 $_anc_id = (int) $menu_item->db_id;
487 ( $_anc_id = get_post_meta( $_anc_id, '_menu_item_menu_item_parent', true ) ) &&
488 ! in_array( $_anc_id, $active_ancestor_item_ids )
490 $active_ancestor_item_ids[] = $_anc_id;
493 if ( 'post_type' == $menu_item->type && 'page' == $menu_item->object ) {
494 // Back compat classes for pages to match wp_page_menu()
495 $classes[] = 'page_item';
496 $classes[] = 'page-item-' . $menu_item->object_id;
497 $classes[] = 'current_page_item';
499 $active_parent_item_ids[] = (int) $menu_item->menu_item_parent;
500 $active_parent_object_ids[] = (int) $menu_item->post_parent;
501 $active_object = $menu_item->object;
503 // if the menu item corresponds to the currently-requested URL
504 } elseif ( 'custom' == $menu_item->object ) {
505 $_root_relative_current = untrailingslashit( $_SERVER['REQUEST_URI'] );
506 $current_url = set_url_scheme( 'http://' . $_SERVER['HTTP_HOST'] . $_root_relative_current );
507 $raw_item_url = strpos( $menu_item->url, '#' ) ? substr( $menu_item->url, 0, strpos( $menu_item->url, '#' ) ) : $menu_item->url;
508 $item_url = untrailingslashit( $raw_item_url );
509 $_indexless_current = untrailingslashit( preg_replace( '/' . preg_quote( $wp_rewrite->index, '/' ) . '$/', '', $current_url ) );
511 if ( $raw_item_url && in_array( $item_url, array( $current_url, $_indexless_current, $_root_relative_current ) ) ) {
512 $classes[] = 'current-menu-item';
513 $menu_items[$key]->current = true;
514 $_anc_id = (int) $menu_item->db_id;
517 ( $_anc_id = get_post_meta( $_anc_id, '_menu_item_menu_item_parent', true ) ) &&
518 ! in_array( $_anc_id, $active_ancestor_item_ids )
520 $active_ancestor_item_ids[] = $_anc_id;
523 if ( in_array( home_url(), array( untrailingslashit( $current_url ), untrailingslashit( $_indexless_current ) ) ) ) {
524 // Back compat for home link to match wp_page_menu()
525 $classes[] = 'current_page_item';
527 $active_parent_item_ids[] = (int) $menu_item->menu_item_parent;
528 $active_parent_object_ids[] = (int) $menu_item->post_parent;
529 $active_object = $menu_item->object;
531 // give front page item current-menu-item class when extra query arguments involved
532 } elseif ( $item_url == $front_page_url && is_front_page() ) {
533 $classes[] = 'current-menu-item';
536 if ( untrailingslashit($item_url) == home_url() )
537 $classes[] = 'menu-item-home';
540 // back-compat with wp_page_menu: add "current_page_parent" to static home page link for any non-page query
541 if ( ! empty( $home_page_id ) && 'post_type' == $menu_item->type && empty( $wp_query->is_page ) && $home_page_id == $menu_item->object_id )
542 $classes[] = 'current_page_parent';
544 $menu_items[$key]->classes = array_unique( $classes );
546 $active_ancestor_item_ids = array_filter( array_unique( $active_ancestor_item_ids ) );
547 $active_parent_item_ids = array_filter( array_unique( $active_parent_item_ids ) );
548 $active_parent_object_ids = array_filter( array_unique( $active_parent_object_ids ) );
550 // set parent's class
551 foreach ( (array) $menu_items as $key => $parent_item ) {
552 $classes = (array) $parent_item->classes;
553 $menu_items[$key]->current_item_ancestor = false;
554 $menu_items[$key]->current_item_parent = false;
557 isset( $parent_item->type ) &&
559 // ancestral post object
561 'post_type' == $parent_item->type &&
562 ! empty( $queried_object->post_type ) &&
563 is_post_type_hierarchical( $queried_object->post_type ) &&
564 in_array( $parent_item->object_id, $queried_object->ancestors ) &&
565 $parent_item->object != $queried_object->ID
570 'taxonomy' == $parent_item->type &&
571 isset( $possible_taxonomy_ancestors[ $parent_item->object ] ) &&
572 in_array( $parent_item->object_id, $possible_taxonomy_ancestors[ $parent_item->object ] ) &&
574 ! isset( $queried_object->term_id ) ||
575 $parent_item->object_id != $queried_object->term_id
580 $classes[] = empty( $queried_object->taxonomy ) ? 'current-' . $queried_object->post_type . '-ancestor' : 'current-' . $queried_object->taxonomy . '-ancestor';
583 if ( in_array( intval( $parent_item->db_id ), $active_ancestor_item_ids ) ) {
584 $classes[] = 'current-menu-ancestor';
585 $menu_items[$key]->current_item_ancestor = true;
587 if ( in_array( $parent_item->db_id, $active_parent_item_ids ) ) {
588 $classes[] = 'current-menu-parent';
589 $menu_items[$key]->current_item_parent = true;
591 if ( in_array( $parent_item->object_id, $active_parent_object_ids ) )
592 $classes[] = 'current-' . $active_object . '-parent';
594 if ( 'post_type' == $parent_item->type && 'page' == $parent_item->object ) {
595 // Back compat classes for pages to match wp_page_menu()
596 if ( in_array('current-menu-parent', $classes) )
597 $classes[] = 'current_page_parent';
598 if ( in_array('current-menu-ancestor', $classes) )
599 $classes[] = 'current_page_ancestor';
602 $menu_items[$key]->classes = array_unique( $classes );
607 * Retrieve the HTML list content for nav menu items.
609 * @uses Walker_Nav_Menu to create HTML list content.
611 * @see Walker::walk() for parameters and return description.
613 function walk_nav_menu_tree( $items, $depth, $r ) {
614 $walker = ( empty($r->walker) ) ? new Walker_Nav_Menu : $r->walker;
615 $args = array( $items, $depth, $r );
617 return call_user_func_array( array($walker, 'walk'), $args );
621 * Prevents a menu item ID from being used more than once.
626 function _nav_menu_item_id_use_once( $id, $item ) {
627 static $_used_ids = array();
628 if ( in_array( $item->ID, $_used_ids ) )
630 $_used_ids[] = $item->ID;
633 add_filter( 'nav_menu_item_id', '_nav_menu_item_id_use_once', 10, 2 );