3 * Nav Menu API: Template functions
6 * @subpackage Nav_Menus
10 /** Walker_Nav_Menu class */
11 require_once ABSPATH . WPINC . '/class-walker-nav-menu.php';
14 * Displays a navigation menu.
17 * @since 4.7.0 Added the `item_spacing` argument.
19 * @staticvar array $menu_id_slugs
21 * @param array $args {
22 * Optional. Array of nav menu arguments.
24 * @type int|string|WP_Term $menu Desired menu. Accepts (matching in order) id, slug, name, menu object. Default empty.
25 * @type string $menu_class CSS class to use for the ul element which forms the menu. Default 'menu'.
26 * @type string $menu_id The ID that is applied to the ul element which forms the menu.
27 * Default is the menu slug, incremented.
28 * @type string $container Whether to wrap the ul, and what to wrap it with. Default 'div'.
29 * @type string $container_class Class that is applied to the container. Default 'menu-{menu slug}-container'.
30 * @type string $container_id The ID that is applied to the container. Default empty.
31 * @type callable|bool $fallback_cb If the menu doesn't exists, a callback function will fire.
32 * Default is 'wp_page_menu'. Set to false for no fallback.
33 * @type string $before Text before the link markup. Default empty.
34 * @type string $after Text after the link markup. Default empty.
35 * @type string $link_before Text before the link text. Default empty.
36 * @type string $link_after Text after the link text. Default empty.
37 * @type bool $echo Whether to echo the menu or return it. Default true.
38 * @type int $depth How many levels of the hierarchy are to be included. 0 means all. Default 0.
39 * @type object $walker Instance of a custom walker class. Default empty.
40 * @type string $theme_location Theme location to be used. Must be registered with register_nav_menu()
41 * in order to be selectable by the user.
42 * @type string $items_wrap How the list items should be wrapped. Default is a ul with an id and class.
43 * Uses printf() format with numbered placeholders.
44 * @type string $item_spacing Whether to preserve whitespace within the menu's HTML. Accepts 'preserve' or 'discard'. Default 'preserve'.
46 * @return object|false|void Menu output if $echo is false, false if there are no items or no menu was found.
48 function wp_nav_menu( $args = array() ) {
49 static $menu_id_slugs = array();
51 $defaults = array( 'menu' => '', 'container' => 'div', 'container_class' => '', 'container_id' => '', 'menu_class' => 'menu', 'menu_id' => '',
52 'echo' => true, 'fallback_cb' => 'wp_page_menu', 'before' => '', 'after' => '', 'link_before' => '', 'link_after' => '', 'items_wrap' => '<ul id="%1$s" class="%2$s">%3$s</ul>', 'item_spacing' => 'preserve',
53 'depth' => 0, 'walker' => '', 'theme_location' => '' );
55 $args = wp_parse_args( $args, $defaults );
57 if ( ! in_array( $args['item_spacing'], array( 'preserve', 'discard' ), true ) ) {
58 // invalid value, fall back to default.
59 $args['item_spacing'] = $defaults['item_spacing'];
63 * Filters the arguments used to display a navigation menu.
69 * @param array $args Array of wp_nav_menu() arguments.
71 $args = apply_filters( 'wp_nav_menu_args', $args );
72 $args = (object) $args;
75 * Filters whether to short-circuit the wp_nav_menu() output.
77 * Returning a non-null value to the filter will short-circuit
78 * wp_nav_menu(), echoing that value if $args->echo is true,
79 * returning that value otherwise.
85 * @param string|null $output Nav menu output to short-circuit with. Default null.
86 * @param stdClass $args An object containing wp_nav_menu() arguments.
88 $nav_menu = apply_filters( 'pre_wp_nav_menu', null, $args );
90 if ( null !== $nav_menu ) {
99 // Get the nav menu based on the requested menu
100 $menu = wp_get_nav_menu_object( $args->menu );
102 // Get the nav menu based on the theme_location
103 if ( ! $menu && $args->theme_location && ( $locations = get_nav_menu_locations() ) && isset( $locations[ $args->theme_location ] ) )
104 $menu = wp_get_nav_menu_object( $locations[ $args->theme_location ] );
106 // get the first menu that has items if we still can't find a menu
107 if ( ! $menu && !$args->theme_location ) {
108 $menus = wp_get_nav_menus();
109 foreach ( $menus as $menu_maybe ) {
110 if ( $menu_items = wp_get_nav_menu_items( $menu_maybe->term_id, array( 'update_post_term_cache' => false ) ) ) {
117 if ( empty( $args->menu ) ) {
121 // If the menu exists, get its items.
122 if ( $menu && ! is_wp_error($menu) && !isset($menu_items) )
123 $menu_items = wp_get_nav_menu_items( $menu->term_id, array( 'update_post_term_cache' => false ) );
126 * If no menu was found:
127 * - Fall back (if one was specified), or bail.
129 * If no menu items were found:
130 * - Fall back, but only if no theme location was specified.
133 if ( ( !$menu || is_wp_error($menu) || ( isset($menu_items) && empty($menu_items) && !$args->theme_location ) )
134 && isset( $args->fallback_cb ) && $args->fallback_cb && is_callable( $args->fallback_cb ) )
135 return call_user_func( $args->fallback_cb, (array) $args );
137 if ( ! $menu || is_wp_error( $menu ) )
140 $nav_menu = $items = '';
142 $show_container = false;
143 if ( $args->container ) {
145 * Filters the list of HTML tags that are valid for use as menu containers.
149 * @param array $tags The acceptable HTML tags for use as menu containers.
150 * Default is array containing 'div' and 'nav'.
152 $allowed_tags = apply_filters( 'wp_nav_menu_container_allowedtags', array( 'div', 'nav' ) );
153 if ( is_string( $args->container ) && in_array( $args->container, $allowed_tags ) ) {
154 $show_container = true;
155 $class = $args->container_class ? ' class="' . esc_attr( $args->container_class ) . '"' : ' class="menu-'. $menu->slug .'-container"';
156 $id = $args->container_id ? ' id="' . esc_attr( $args->container_id ) . '"' : '';
157 $nav_menu .= '<'. $args->container . $id . $class . '>';
161 // Set up the $menu_item variables
162 _wp_menu_item_classes_by_context( $menu_items );
164 $sorted_menu_items = $menu_items_with_children = array();
165 foreach ( (array) $menu_items as $menu_item ) {
166 $sorted_menu_items[ $menu_item->menu_order ] = $menu_item;
167 if ( $menu_item->menu_item_parent )
168 $menu_items_with_children[ $menu_item->menu_item_parent ] = true;
171 // Add the menu-item-has-children class where applicable
172 if ( $menu_items_with_children ) {
173 foreach ( $sorted_menu_items as &$menu_item ) {
174 if ( isset( $menu_items_with_children[ $menu_item->ID ] ) )
175 $menu_item->classes[] = 'menu-item-has-children';
179 unset( $menu_items, $menu_item );
182 * Filters the sorted list of menu item objects before generating the menu's HTML.
186 * @param array $sorted_menu_items The menu items, sorted by each menu item's menu order.
187 * @param stdClass $args An object containing wp_nav_menu() arguments.
189 $sorted_menu_items = apply_filters( 'wp_nav_menu_objects', $sorted_menu_items, $args );
191 $items .= walk_nav_menu_tree( $sorted_menu_items, $args->depth, $args );
192 unset($sorted_menu_items);
195 if ( ! empty( $args->menu_id ) ) {
196 $wrap_id = $args->menu_id;
198 $wrap_id = 'menu-' . $menu->slug;
199 while ( in_array( $wrap_id, $menu_id_slugs ) ) {
200 if ( preg_match( '#-(\d+)$#', $wrap_id, $matches ) )
201 $wrap_id = preg_replace('#-(\d+)$#', '-' . ++$matches[1], $wrap_id );
203 $wrap_id = $wrap_id . '-1';
206 $menu_id_slugs[] = $wrap_id;
208 $wrap_class = $args->menu_class ? $args->menu_class : '';
211 * Filters the HTML list content for navigation menus.
217 * @param string $items The HTML list content for the menu items.
218 * @param stdClass $args An object containing wp_nav_menu() arguments.
220 $items = apply_filters( 'wp_nav_menu_items', $items, $args );
222 * Filters the HTML list content for a specific navigation menu.
228 * @param string $items The HTML list content for the menu items.
229 * @param stdClass $args An object containing wp_nav_menu() arguments.
231 $items = apply_filters( "wp_nav_menu_{$menu->slug}_items", $items, $args );
233 // Don't print any markup if there are no items at this point.
234 if ( empty( $items ) )
237 $nav_menu .= sprintf( $args->items_wrap, esc_attr( $wrap_id ), esc_attr( $wrap_class ), $items );
240 if ( $show_container )
241 $nav_menu .= '</' . $args->container . '>';
244 * Filters the HTML content for navigation menus.
250 * @param string $nav_menu The HTML content for the navigation menu.
251 * @param stdClass $args An object containing wp_nav_menu() arguments.
253 $nav_menu = apply_filters( 'wp_nav_menu', $nav_menu, $args );
262 * Add the class property classes for the current context, if applicable.
267 * @global WP_Query $wp_query
268 * @global WP_Rewrite $wp_rewrite
270 * @param array $menu_items The current menu item objects to which to add the class property information.
272 function _wp_menu_item_classes_by_context( &$menu_items ) {
273 global $wp_query, $wp_rewrite;
275 $queried_object = $wp_query->get_queried_object();
276 $queried_object_id = (int) $wp_query->queried_object_id;
279 $active_ancestor_item_ids = array();
280 $active_parent_item_ids = array();
281 $active_parent_object_ids = array();
282 $possible_taxonomy_ancestors = array();
283 $possible_object_parents = array();
284 $home_page_id = (int) get_option( 'page_for_posts' );
286 if ( $wp_query->is_singular && ! empty( $queried_object->post_type ) && ! is_post_type_hierarchical( $queried_object->post_type ) ) {
287 foreach ( (array) get_object_taxonomies( $queried_object->post_type ) as $taxonomy ) {
288 if ( is_taxonomy_hierarchical( $taxonomy ) ) {
289 $term_hierarchy = _get_term_hierarchy( $taxonomy );
290 $terms = wp_get_object_terms( $queried_object_id, $taxonomy, array( 'fields' => 'ids' ) );
291 if ( is_array( $terms ) ) {
292 $possible_object_parents = array_merge( $possible_object_parents, $terms );
293 $term_to_ancestor = array();
294 foreach ( (array) $term_hierarchy as $anc => $descs ) {
295 foreach ( (array) $descs as $desc )
296 $term_to_ancestor[ $desc ] = $anc;
299 foreach ( $terms as $desc ) {
301 $possible_taxonomy_ancestors[ $taxonomy ][] = $desc;
302 if ( isset( $term_to_ancestor[ $desc ] ) ) {
303 $_desc = $term_to_ancestor[ $desc ];
304 unset( $term_to_ancestor[ $desc ] );
309 } while ( ! empty( $desc ) );
314 } elseif ( ! empty( $queried_object->taxonomy ) && is_taxonomy_hierarchical( $queried_object->taxonomy ) ) {
315 $term_hierarchy = _get_term_hierarchy( $queried_object->taxonomy );
316 $term_to_ancestor = array();
317 foreach ( (array) $term_hierarchy as $anc => $descs ) {
318 foreach ( (array) $descs as $desc )
319 $term_to_ancestor[ $desc ] = $anc;
321 $desc = $queried_object->term_id;
323 $possible_taxonomy_ancestors[ $queried_object->taxonomy ][] = $desc;
324 if ( isset( $term_to_ancestor[ $desc ] ) ) {
325 $_desc = $term_to_ancestor[ $desc ];
326 unset( $term_to_ancestor[ $desc ] );
331 } while ( ! empty( $desc ) );
334 $possible_object_parents = array_filter( $possible_object_parents );
336 $front_page_url = home_url();
337 $front_page_id = (int) get_option( 'page_on_front' );
339 foreach ( (array) $menu_items as $key => $menu_item ) {
341 $menu_items[$key]->current = false;
343 $classes = (array) $menu_item->classes;
344 $classes[] = 'menu-item';
345 $classes[] = 'menu-item-type-' . $menu_item->type;
346 $classes[] = 'menu-item-object-' . $menu_item->object;
348 // This menu item is set as the 'Front Page'.
349 if ( 'post_type' === $menu_item->type && $front_page_id === (int) $menu_item->object_id ) {
350 $classes[] = 'menu-item-home';
353 // if the menu item corresponds to a taxonomy term for the currently-queried non-hierarchical post object
354 if ( $wp_query->is_singular && 'taxonomy' == $menu_item->type && in_array( $menu_item->object_id, $possible_object_parents ) ) {
355 $active_parent_object_ids[] = (int) $menu_item->object_id;
356 $active_parent_item_ids[] = (int) $menu_item->db_id;
357 $active_object = $queried_object->post_type;
359 // if the menu item corresponds to the currently-queried post or taxonomy object
361 $menu_item->object_id == $queried_object_id &&
363 ( ! empty( $home_page_id ) && 'post_type' == $menu_item->type && $wp_query->is_home && $home_page_id == $menu_item->object_id ) ||
364 ( 'post_type' == $menu_item->type && $wp_query->is_singular ) ||
365 ( 'taxonomy' == $menu_item->type && ( $wp_query->is_category || $wp_query->is_tag || $wp_query->is_tax ) && $queried_object->taxonomy == $menu_item->object )
368 $classes[] = 'current-menu-item';
369 $menu_items[$key]->current = true;
370 $_anc_id = (int) $menu_item->db_id;
373 ( $_anc_id = get_post_meta( $_anc_id, '_menu_item_menu_item_parent', true ) ) &&
374 ! in_array( $_anc_id, $active_ancestor_item_ids )
376 $active_ancestor_item_ids[] = $_anc_id;
379 if ( 'post_type' == $menu_item->type && 'page' == $menu_item->object ) {
380 // Back compat classes for pages to match wp_page_menu()
381 $classes[] = 'page_item';
382 $classes[] = 'page-item-' . $menu_item->object_id;
383 $classes[] = 'current_page_item';
386 $active_parent_item_ids[] = (int) $menu_item->menu_item_parent;
387 $active_parent_object_ids[] = (int) $menu_item->post_parent;
388 $active_object = $menu_item->object;
390 // if the menu item corresponds to the currently-queried post type archive
392 'post_type_archive' == $menu_item->type &&
393 is_post_type_archive( array( $menu_item->object ) )
395 $classes[] = 'current-menu-item';
396 $menu_items[$key]->current = true;
397 // if the menu item corresponds to the currently-requested URL
398 } elseif ( 'custom' == $menu_item->object && isset( $_SERVER['HTTP_HOST'] ) ) {
399 $_root_relative_current = untrailingslashit( $_SERVER['REQUEST_URI'] );
400 $current_url = set_url_scheme( 'http://' . $_SERVER['HTTP_HOST'] . $_root_relative_current );
401 $raw_item_url = strpos( $menu_item->url, '#' ) ? substr( $menu_item->url, 0, strpos( $menu_item->url, '#' ) ) : $menu_item->url;
402 $item_url = set_url_scheme( untrailingslashit( $raw_item_url ) );
403 $_indexless_current = untrailingslashit( preg_replace( '/' . preg_quote( $wp_rewrite->index, '/' ) . '$/', '', $current_url ) );
405 if ( $raw_item_url && in_array( $item_url, array( $current_url, $_indexless_current, $_root_relative_current ) ) ) {
406 $classes[] = 'current-menu-item';
407 $menu_items[$key]->current = true;
408 $_anc_id = (int) $menu_item->db_id;
411 ( $_anc_id = get_post_meta( $_anc_id, '_menu_item_menu_item_parent', true ) ) &&
412 ! in_array( $_anc_id, $active_ancestor_item_ids )
414 $active_ancestor_item_ids[] = $_anc_id;
417 if ( in_array( home_url(), array( untrailingslashit( $current_url ), untrailingslashit( $_indexless_current ) ) ) ) {
418 // Back compat for home link to match wp_page_menu()
419 $classes[] = 'current_page_item';
421 $active_parent_item_ids[] = (int) $menu_item->menu_item_parent;
422 $active_parent_object_ids[] = (int) $menu_item->post_parent;
423 $active_object = $menu_item->object;
425 // give front page item current-menu-item class when extra query arguments involved
426 } elseif ( $item_url == $front_page_url && is_front_page() ) {
427 $classes[] = 'current-menu-item';
430 if ( untrailingslashit($item_url) == home_url() )
431 $classes[] = 'menu-item-home';
434 // back-compat with wp_page_menu: add "current_page_parent" to static home page link for any non-page query
435 if ( ! empty( $home_page_id ) && 'post_type' == $menu_item->type && empty( $wp_query->is_page ) && $home_page_id == $menu_item->object_id )
436 $classes[] = 'current_page_parent';
438 $menu_items[$key]->classes = array_unique( $classes );
440 $active_ancestor_item_ids = array_filter( array_unique( $active_ancestor_item_ids ) );
441 $active_parent_item_ids = array_filter( array_unique( $active_parent_item_ids ) );
442 $active_parent_object_ids = array_filter( array_unique( $active_parent_object_ids ) );
444 // set parent's class
445 foreach ( (array) $menu_items as $key => $parent_item ) {
446 $classes = (array) $parent_item->classes;
447 $menu_items[$key]->current_item_ancestor = false;
448 $menu_items[$key]->current_item_parent = false;
451 isset( $parent_item->type ) &&
453 // ancestral post object
455 'post_type' == $parent_item->type &&
456 ! empty( $queried_object->post_type ) &&
457 is_post_type_hierarchical( $queried_object->post_type ) &&
458 in_array( $parent_item->object_id, $queried_object->ancestors ) &&
459 $parent_item->object != $queried_object->ID
464 'taxonomy' == $parent_item->type &&
465 isset( $possible_taxonomy_ancestors[ $parent_item->object ] ) &&
466 in_array( $parent_item->object_id, $possible_taxonomy_ancestors[ $parent_item->object ] ) &&
468 ! isset( $queried_object->term_id ) ||
469 $parent_item->object_id != $queried_object->term_id
474 $classes[] = empty( $queried_object->taxonomy ) ? 'current-' . $queried_object->post_type . '-ancestor' : 'current-' . $queried_object->taxonomy . '-ancestor';
477 if ( in_array( intval( $parent_item->db_id ), $active_ancestor_item_ids ) ) {
478 $classes[] = 'current-menu-ancestor';
479 $menu_items[$key]->current_item_ancestor = true;
481 if ( in_array( $parent_item->db_id, $active_parent_item_ids ) ) {
482 $classes[] = 'current-menu-parent';
483 $menu_items[$key]->current_item_parent = true;
485 if ( in_array( $parent_item->object_id, $active_parent_object_ids ) )
486 $classes[] = 'current-' . $active_object . '-parent';
488 if ( 'post_type' == $parent_item->type && 'page' == $parent_item->object ) {
489 // Back compat classes for pages to match wp_page_menu()
490 if ( in_array('current-menu-parent', $classes) )
491 $classes[] = 'current_page_parent';
492 if ( in_array('current-menu-ancestor', $classes) )
493 $classes[] = 'current_page_ancestor';
496 $menu_items[$key]->classes = array_unique( $classes );
501 * Retrieve the HTML list content for nav menu items.
503 * @uses Walker_Nav_Menu to create HTML list content.
506 * @param array $items The menu items, sorted by each menu item's menu order.
507 * @param int $depth Depth of the item in reference to parents.
508 * @param stdClass $r An object containing wp_nav_menu() arguments.
509 * @return string The HTML list content for the menu items.
511 function walk_nav_menu_tree( $items, $depth, $r ) {
512 $walker = ( empty($r->walker) ) ? new Walker_Nav_Menu : $r->walker;
513 $args = array( $items, $depth, $r );
515 return call_user_func_array( array( $walker, 'walk' ), $args );
519 * Prevents a menu item ID from being used more than once.
524 * @staticvar array $used_ids
526 * @param object $item
529 function _nav_menu_item_id_use_once( $id, $item ) {
530 static $_used_ids = array();
531 if ( in_array( $item->ID, $_used_ids ) ) {
534 $_used_ids[] = $item->ID;