WordPress Version: 1.1
/**
* Displays a navigation menu.
*
* @since 3.0.0
* @since 4.7.0 Added the `item_spacing` argument.
* @since 5.5.0 Added the `container_aria_label` argument.
*
* @param array $args {
* Optional. Array of nav menu arguments.
*
* @type int|string|WP_Term $menu Desired menu. Accepts a menu ID, slug, name, or object.
* Default empty.
* @type string $menu_class CSS class to use for the ul element which forms the menu.
* Default 'menu'.
* @type string $menu_id The ID that is applied to the ul element which forms the menu.
* Default is the menu slug, incremented.
* @type string $container Whether to wrap the ul, and what to wrap it with.
* Default 'div'.
* @type string $container_class Class that is applied to the container.
* Default 'menu-{menu slug}-container'.
* @type string $container_id The ID that is applied to the container. Default empty.
* @type string $container_aria_label The aria-label attribute that is applied to the container
* when it's a nav element. Default empty.
* @type callable|false $fallback_cb If the menu doesn't exist, a callback function will fire.
* Default is 'wp_page_menu'. Set to false for no fallback.
* @type string $before Text before the link markup. Default empty.
* @type string $after Text after the link markup. Default empty.
* @type string $link_before Text before the link text. Default empty.
* @type string $link_after Text after the link text. Default empty.
* @type bool $echo Whether to echo the menu or return it. Default true.
* @type int $depth How many levels of the hierarchy are to be included.
* 0 means all. Default 0.
* Default 0.
* @type object $walker Instance of a custom walker class. Default empty.
* @type string $theme_location Theme location to be used. Must be registered with
* register_nav_menu() in order to be selectable by the user.
* @type string $items_wrap How the list items should be wrapped. Uses printf() format with
* numbered placeholders. Default is a ul with an id and class.
* @type string $item_spacing Whether to preserve whitespace within the menu's HTML.
* Accepts 'preserve' or 'discard'. Default 'preserve'.
* }
* @return void|string|false Void if 'echo' argument is true, menu output if 'echo' is false.
* False if there are no items or no menu was found.
*/
function wp_nav_menu($args = array())
{
static $menu_id_slugs = array();
$defaults = array('menu' => '', 'container' => 'div', 'container_class' => '', 'container_id' => '', 'container_aria_label' => '', 'menu_class' => 'menu', 'menu_id' => '', 'echo' => true, 'fallback_cb' => 'wp_page_menu', 'before' => '', 'after' => '', 'link_before' => '', 'link_after' => '', 'items_wrap' => '<ul id="%1$s" class="%2$s">%3$s</ul>', 'item_spacing' => 'preserve', 'depth' => 0, 'walker' => '', 'theme_location' => '');
$args = wp_parse_args($args, $defaults);
if (!in_array($args['item_spacing'], array('preserve', 'discard'), true)) {
// Invalid value, fall back to default.
$args['item_spacing'] = $defaults['item_spacing'];
}
/**
* Filters the arguments used to display a navigation menu.
*
* @since 3.0.0
*
* @see wp_nav_menu()
*
* @param array $args Array of wp_nav_menu() arguments.
*/
$args = apply_filters('wp_nav_menu_args', $args);
$args = (object) $args;
/**
* Filters whether to short-circuit the wp_nav_menu() output.
*
* Returning a non-null value from the filter will short-circuit wp_nav_menu(),
* echoing that value if $args->echo is true, returning that value otherwise.
*
* @since 3.9.0
*
* @see wp_nav_menu()
*
* @param string|null $output Nav menu output to short-circuit with. Default null.
* @param stdClass $args An object containing wp_nav_menu() arguments.
*/
$nav_menu = apply_filters('pre_wp_nav_menu', null, $args);
if (null !== $nav_menu) {
if ($args->echo) {
echo $nav_menu;
return;
}
return $nav_menu;
}
// Get the nav menu based on the requested menu.
$menu = wp_get_nav_menu_object($args->menu);
// Get the nav menu based on the theme_location.
$locations = get_nav_menu_locations();
if (!$menu && $args->theme_location && $locations && isset($locations[$args->theme_location])) {
$menu = wp_get_nav_menu_object($locations[$args->theme_location]);
}
// Get the first menu that has items if we still can't find a menu.
if (!$menu && !$args->theme_location) {
$menus = wp_get_nav_menus();
foreach ($menus as $menu_maybe) {
$menu_items = wp_get_nav_menu_items($menu_maybe->term_id, array('update_post_term_cache' => false));
if ($menu_items) {
$menu = $menu_maybe;
break;
}
}
}
if (empty($args->menu)) {
$args->menu = $menu;
}
// If the menu exists, get its items.
if ($menu && !is_wp_error($menu) && !isset($menu_items)) {
$menu_items = wp_get_nav_menu_items($menu->term_id, array('update_post_term_cache' => false));
}
/*
* If no menu was found:
* - Fall back (if one was specified), or bail.
*
* If no menu items were found:
* - Fall back, but only if no theme location was specified.
* - Otherwise, bail.
*/
if ((!$menu || is_wp_error($menu) || isset($menu_items) && empty($menu_items) && !$args->theme_location) && isset($args->fallback_cb) && $args->fallback_cb && is_callable($args->fallback_cb)) {
return call_user_func($args->fallback_cb, (array) $args);
}
if (!$menu || is_wp_error($menu)) {
return false;
}
$nav_menu = '';
$items = '';
$show_container = false;
if ($args->container) {
/**
* Filters the list of HTML tags that are valid for use as menu containers.
*
* @since 3.0.0
*
* @param string[] $tags The acceptable HTML tags for use as menu containers.
* Default is array containing 'div' and 'nav'.
*/
$allowed_tags = apply_filters('wp_nav_menu_container_allowedtags', array('div', 'nav'));
if (is_string($args->container) && in_array($args->container, $allowed_tags, true)) {
$show_container = true;
$class = $args->container_class ? ' class="' . esc_attr($args->container_class) . '"' : (' class="menu-' . $menu->slug . '-container"');
$id = $args->container_id ? ' id="' . esc_attr($args->container_id) . '"' : '';
$aria_label = ('nav' === $args->container && $args->container_aria_label) ? ' aria-label="' . esc_attr($args->container_aria_label) . '"' : '';
$nav_menu .= '<' . $args->container . $id . $class . $aria_label . '>';
}
}
// Set up the $menu_item variables.
_wp_menu_item_classes_by_context($menu_items);
$sorted_menu_items = array();
$menu_items_tree = array();
$menu_items_with_children = array();
foreach ((array) $menu_items as $menu_item) {
$sorted_menu_items[$menu_item->menu_order] = $menu_item;
$menu_items_tree[$menu_item->ID] = $menu_item->menu_item_parent;
if ($menu_item->menu_item_parent) {
$menu_items_with_children[$menu_item->menu_item_parent] = 1;
}
}
// Calculate the depth of each menu item with children.
foreach ($menu_items_with_children as $menu_item_key => &$menu_item_depth) {
$menu_item_parent = $menu_items_tree[$menu_item_key];
while ($menu_item_parent) {
$menu_item_depth = $menu_item_depth + 1;
$menu_item_parent = $menu_items_tree[$menu_item_parent];
}
}
// Add the menu-item-has-children class where applicable.
if ($menu_items_with_children) {
foreach ($sorted_menu_items as &$menu_item) {
if (isset($menu_items_with_children[$menu_item->ID]) && ($args->depth <= 0 || $menu_items_with_children[$menu_item->ID] < $args->depth)) {
$menu_item->classes[] = 'menu-item-has-children';
}
}
}
unset($menu_items_tree, $menu_items_with_children, $menu_items, $menu_item);
/**
* Filters the sorted list of menu item objects before generating the menu's HTML.
*
* @since 3.1.0
*
* @param array $sorted_menu_items The menu items, sorted by each menu item's menu order.
* @param stdClass $args An object containing wp_nav_menu() arguments.
*/
$sorted_menu_items = apply_filters('wp_nav_menu_objects', $sorted_menu_items, $args);
$items .= walk_nav_menu_tree($sorted_menu_items, $args->depth, $args);
unset($sorted_menu_items);
// Attributes.
if (!empty($args->menu_id)) {
$wrap_id = $args->menu_id;
} else {
$wrap_id = 'menu-' . $menu->slug;
while (in_array($wrap_id, $menu_id_slugs, true)) {
if (preg_match('#-(\d+)$#', $wrap_id, $matches)) {
$wrap_id = preg_replace('#-(\d+)$#', '-' . ++$matches[1], $wrap_id);
} else {
$wrap_id = $wrap_id . '-1';
}
}
}
$menu_id_slugs[] = $wrap_id;
$wrap_class = $args->menu_class ? $args->menu_class : '';
/**
* Filters the HTML list content for navigation menus.
*
* @since 3.0.0
*
* @see wp_nav_menu()
*
* @param string $items The HTML list content for the menu items.
* @param stdClass $args An object containing wp_nav_menu() arguments.
*/
$items = apply_filters('wp_nav_menu_items', $items, $args);
/**
* Filters the HTML list content for a specific navigation menu.
*
* @since 3.0.0
*
* @see wp_nav_menu()
*
* @param string $items The HTML list content for the menu items.
* @param stdClass $args An object containing wp_nav_menu() arguments.
*/
$items = apply_filters("wp_nav_menu_{$menu->slug}_items", $items, $args);
// Don't print any markup if there are no items at this point.
if (empty($items)) {
return false;
}
$nav_menu .= sprintf($args->items_wrap, esc_attr($wrap_id), esc_attr($wrap_class), $items);
unset($items);
if ($show_container) {
$nav_menu .= '</' . $args->container . '>';
}
/**
* Filters the HTML content for navigation menus.
*
* @since 3.0.0
*
* @see wp_nav_menu()
*
* @param string $nav_menu The HTML content for the navigation menu.
* @param stdClass $args An object containing wp_nav_menu() arguments.
*/
$nav_menu = apply_filters('wp_nav_menu', $nav_menu, $args);
if ($args->echo) {
echo $nav_menu;
} else {
return $nav_menu;
}
}