WordPress/wp-includes/nav-menu-template.php

<?php
/**
 * Displays a navigation menu.
 *
 * Optional $args contents:
 *
 * id - The menu id. Defaults to blank.
 * slug - The menu slug. Defaults to blank.
 * menu_class - CSS class to use for the div container of the menu list. Defaults to 'menu'.
 * format - Whether to format the ul. Defaults to 'div'.
 * fallback_cb - If the menu doesn't exists, a callback function will fire. Defaults to 'wp_page_menu'.
 * before_link - Output text before the link.
 * after_link - Output text after the link.
 * before_title - Output text before the link text.
 * before_title - Output text after the link text.
 * echo - Whether to echo the menu or return it. Defaults to echo.
 *
 * TODO:
 * show_home - If you set this argument, then it will display the link to the home page. The show_home argument really just needs to be set to the value of the text of the link.
 *
 * @since 3.0.0
 *
 * @param array $args Arguments
 */
function wp_nav_menu( $args = array() ) {
	$defaults = array( 'menu' => '', 'container' => 'div', 'container_class' => '', 'menu_class' => 'menu', 'echo' => true,
	'fallback_cb' => 'wp_page_menu', 'before_link' => '', 'after_link' => '', 'before_title' => '', 'after_title' => '', );

	$args = wp_parse_args( $args, $defaults );
	$args = apply_filters( 'wp_nav_menu_args', $args );
	$args = (object) $args;

	// Get the nav menu
	$menu = wp_get_nav_menu_object( $args->menu );

	// If we couldn't find a menu based off the name, id or slug,
	// get the first menu that has items.
	if ( !$menu ) {
		$menus = wp_get_nav_menus();
		foreach ( $menus as $menu_maybe ) {
			if ( wp_get_nav_menu_items($menu_maybe->term_id) ) {
				$menu = $menu_maybe;
				break;
			}
		}
	}

	if ( !is_wp_error($menu) )
		$args->menu = $menu->term_id;
	$nav_menu = '';

	if ( 'div' == $args->container ) {
		$class = $args->container_class ? ' class="' . esc_attr($args->container_class) . '"' : '';

		if ( is_nav_menu($menu) ) {
			$nav_menu .= '<div id="menu-' . $menu->slug . '"'. $class .'>';
		} else {
			$nav_menu .= '<div'. $class .'>';
		}
	}

	$nav_menu .= wp_get_nav_menu( $args );

	if ( 'div' == $args->container )
		$nav_menu .= '</div>';

	$nav_menu = apply_filters( 'wp_nav_menu', $nav_menu, $args );

	if ( $args->echo )
		echo $nav_menu;
	else
		return $nav_menu;
}

/**
 * Returns a Navigation Menu.
 *
 * See wp_nav_menu() for args.
 *
 * @since 3.0.0
 *
 * @param array $args Arguments
 * @return mixed $output False if menu doesn't exists, else, returns the menu.
 **/
function wp_get_nav_menu( $args = array() ) {
	$defaults = array( 'menu' => '', 'menu_class' => 'menu', 'context' => 'frontend',
	'fallback_cb' => '', 'before_link' => '', 'after_link' => '', 'before_title' => '', 'after_title' => '', );

	$args = wp_parse_args( $args, $defaults );
	$args = apply_filters( 'wp_get_nav_menu_args', $args );
	$args = (object) $args;

	// Variable setup
	$nav_menu = '';
	$items = '';
	$current_parent = 0;
	$parent_stack = array();
	$parent_menu_order = array();

	// Get the menu object
	$menu = wp_get_nav_menu_object( $args->menu );

	// If the menu exists, get it's items.
	if ( $menu && !is_wp_error($menu) )
		$menu_items = wp_get_nav_menu_items( $menu->term_id, 'backend' );

	// If no menu was found or if the menu has no items, call the fallback_cb
	if ( !$menu || is_wp_error($menu) || ( isset($menu_items) && empty($menu_items) ) ) {
		if ( function_exists($args->fallback_cb) ) {
			$_args = array_merge( (array)$args, array('echo' => false) );
			return call_user_func( $args->fallback_cb, $_args );
		}
	}

	foreach ( $menu_items as $key => $menu_item ) {
		// Set up the $menu_item variables
		$menu_item = wp_setup_nav_menu_item( $menu_item, 'frontend' );

		$type = $menu_item->append;
		$maybe_value = 'frontend' == $args->context ? '' : ' value="'. $menu_item->ID .'"';
		$classes = 'frontend' == $args->context ? ' class="menu-item-type-'. $type . $menu_item->li_class .'"' : '';

		$items .= '<li id="menu-item-'. $menu_item->ID .'"'. $maybe_value . $classes .'>';
		$items .= wp_get_nav_menu_item( $menu_item, $args->context, $args );

		// Indent children
		$last_item = ( count( $menu_items ) == $menu_item->menu_order );
		if ( $last_item || $current_parent != $menu_items[$key + 1]->post_parent ) {
			if ( $last_item || in_array( $menu_items[$key + 1]->post_parent, $parent_stack ) ) {
				$items .= '</li>';
				while ( !empty( $parent_stack ) && ($last_item || $menu_items[$key + 1]->post_parent != $current_parent ) ) {
					$items .= '</ul></li>';
					$current_parent = array_pop( $parent_stack );
				}
			} else {
				array_push( $parent_stack, $current_parent );
				$current_parent = $menu_item->ID;
				$items .= '<ul class="sub-menu">';
			}
		} else {
			$items .= '</li>';
		}
	}

	// CSS class
	$ul_class = $args->menu_class ? ' class="'. $args->menu_class .'"' : '';
	$nav_menu .= '<ul'. $ul_class .'>';

	// Allow plugins to hook into the menu to add their own <li>'s
	if ( 'frontend' == $args->context ) {
		$items = apply_filters( 'wp_nav_menu_items', $items, $args );
		$items = apply_filters( "wp_nav_menu_{$menu->slug}_items", $items, $args );
		$nav_menu .= $items;
	} else {
		$nav_menu .= $items;
	}

	$nav_menu .= '</ul>';

	return apply_filters( 'wp_get_nav_menu', $nav_menu );
}

/**
 * Returns the menu item formatted based on it's context.
 *
 * @since 3.0.0
 *
 * @param string $menu_item The menu item to format.
 * @param string $context The context to which the menu item will be formatted to.
 * @param string $args Optional. Args used for the 'template' context.
 * @return string $output The menu formatted menu item.
 */
function wp_get_nav_menu_item( $menu_item, $context = 'frontend', $args = array() ) {
	$output = '';
	switch ( $context ) {
		case 'frontend':
			$attributes  = ( isset($menu_item->anchor_title) && '' != $menu_item->anchor_title ) ? ' title="'. esc_attr($menu_item->anchor_title) .'"' : '';
			$attributes .= ( isset($menu_item->target) && '' != $menu_item->target ) ? ' target="'. esc_attr($menu_item->target) .'"' : '';
			$attributes .= ( isset($menu_item->classes) && '' != $menu_item->classes ) ? ' class="'. esc_attr($menu_item->classes) .'"' : '';
			$attributes .= ( isset($menu_item->xfn) && '' != $menu_item->xfn ) ? ' rel="'. esc_attr($menu_item->xfn) .'"' : '';
			$attributes .= ( isset($menu_item->url) && '' != $menu_item->url ) ? ' href="'. esc_attr($menu_item->url) .'"' : '';

			$output .= esc_html( $args->before_link );
			$output .= '<a'. $attributes .'>';
			$output .= esc_html( $args->before_title . $menu_item->title . $args->after_title );
			$output .= '</a>';
			$output .= esc_html( $args->after_link );

			break;

		case 'backend':
			$output .= '<dl><dt>';
			$output .= '<span class="item-title">'. esc_html($menu_item->title) .'</span>';
			$output .= '<span class="item-controls">';
			if ( 'custom' == $menu_item->type ) {
				$label = __('Custom');
			} elseif ( 'post_type' == $menu_item->type ) {
				$type_obj = get_post_type_object($menu_item->append);
				$label = $type_obj->singular_label;
			} elseif ( 'taxonomy' == $menu_item->type ) {
				$taxonomy = get_taxonomy($menu_item->append);
				$label = $taxonomy->singular_label;
			} else {
				$label = $menu_item->append;
			}
			$output .= '<span class="item-type">'. esc_html($label) .'</span>';

			// Actions
			$output .= '<a class="item-edit thickbox" id="edit'. esc_attr( $menu_item->menu_order ) .'" value="'. esc_attr( $menu_item->menu_order ) .'" title="'. __('Edit Menu Item') .'" href="#TB_inline?height=540&width=300&inlineId=menu-item-settings">'. __('Edit') .'</a> | ';
			$output .= '<a class="item-delete" id="delete'. esc_attr( $menu_item->menu_order ) .'" value="'. esc_attr( $menu_item->menu_order ) .'">'. __('Delete') .'</a>';

			$output .= '</dt></dl>';

			// Menu Item Settings
			$output .= '<input type="hidden" name="menu-item-db-id[]" id="menu-item-db-id'. esc_attr( $menu_item->menu_order ) .'" value="'. esc_attr( $menu_item->ID ) .'" />';
			$output .= '<input type="hidden" name="menu-item-object-id[]" id="menu-item-object-id'. esc_attr( $menu_item->menu_order ) .'" value="'. esc_attr( $menu_item->object_id ) .'" />';
			$output .= '<input type="hidden" name="menu-item-parent-id[]" id="menu-item-parent-id'. esc_attr( $menu_item->menu_order ) .'" value="'. esc_attr( $menu_item->post_parent ) .'" />';
			$output .= '<input type="hidden" name="menu-item-position[]" id="menu-item-position'. esc_attr( $menu_item->menu_order ) .'" value="'. esc_attr( $menu_item->menu_order ) .'" />';
			$output .= '<input type="hidden" name="menu-item-type[]" id="menu-item-type'. esc_attr( $menu_item->menu_order ) .'" value="'. esc_attr( $menu_item->type ) .'" />';
			$output .= '<input type="hidden" name="menu-item-append[]" id="menu-item-append'. esc_attr( $menu_item->menu_order ) .'" value="'. esc_attr( $menu_item->append ) .'" />';
			$output .= '<input type="hidden" name="menu-item-title[]" id="menu-item-title'. esc_attr( $menu_item->menu_order ) .'" value="'. esc_attr( $menu_item->title ) .'" />';
			$output .= '<input type="hidden" name="menu-item-url[]" id="menu-item-url'. esc_attr( $menu_item->menu_order ) .'" value="'. esc_attr( $menu_item->url ) .'" />';
			$output .= '<input type="hidden" name="menu-item-description[]" id="menu-item-description'. esc_attr( $menu_item->menu_order ) .'" value="'. esc_attr( $menu_item->description ) .'" />';
			$output .= '<input type="hidden" name="menu-item-classes[]" id="menu-item-classes'. esc_attr( $menu_item->menu_order ) .'" value="'. esc_attr( $menu_item->classes ) .'" />';
			$output .= '<input type="hidden" name="menu-item-xfn[]" id="menu-item-xfn'. esc_attr( $menu_item->menu_order ) .'" value="'. esc_attr( $menu_item->xfn ) .'" />';
			$output .= '<input type="hidden" name="menu-item-attr-title[]" id="menu-item-attr-title'. esc_attr( $menu_item->menu_order ) .'" value="'.esc_attr( $menu_item->post_excerpt )  .'" />';
			$output .= '<input type="hidden" name="menu-item-target[]" id="menu-item-target'. esc_attr( $menu_item->menu_order ) .'" value="'. esc_attr( $menu_item->target ) .'" />';
			break;

		case 'custom':
			$menu_id = 'menu-item-' . $menu_item->db_id;
			$output .= '<label class="menu-item-title"><input type="checkbox" id="'. esc_attr( $menu_id ) .'" name="'. esc_attr( $menu_item->title ) .'" value="'. esc_attr( $menu_item->url ) .'" />'. $menu_item->title .'</label>';

			// Menu item hidden fields
			$output .= '<input type="hidden" class="menu-item-db-id" value="'. esc_attr( $menu_item->db_id ) .'" />';
			$output .= '<input type="hidden" class="menu-item-object-id" value="'. esc_attr( $menu_item->object_id ) .'" />';
			$output .= '<input type="hidden" class="menu-item-parent-id" value="'. esc_attr( $menu_item->parent_id ) .'" />';
			$output .= '<input type="hidden" class="menu-item-type" value="'. esc_attr( $menu_item->type ) .'" />';
			$output .= '<input type="hidden" class="menu-item-append" value="'. esc_attr( $menu_item->append ) .'" />';
			$output .= '<input type="hidden" class="menu-item-title" value="'. esc_attr( $menu_item->title ) .'" />';
			$output .= '<input type="hidden" class="menu-item-url" value="'. esc_attr( $menu_item->url ) .'" />';
			$output .= '<input type="hidden" class="menu-item-target" value="'. esc_attr( $menu_item->target ) .'" />';
			$output .= '<input type="hidden" class="menu-item-attr_title" value="'. esc_attr( $menu_item->attr_title ) .'" />';
			$output .= '<input type="hidden" class="menu-item-description" value="'. esc_attr( $menu_item->description ) .'" />';
			$output .= '<input type="hidden" class="menu-item-classes" value="'. esc_attr( $menu_item->classes ) .'" />';
			$output .= '<input type="hidden" class="menu-item-xfn" value="'. esc_attr( $menu_item->xfn ) .'" />';
			break;

		case 'taxonomy':
		case 'post_type':
			$menu_id = 'menu-item-' . $menu_item->db_id;
			$output .= '<label class="menu-item-title"><input type="checkbox" id="'. esc_attr( $menu_id ) .'" name="'. esc_attr( $menu_item->title ) .'" value="'. esc_attr( $menu_item->url ) .'" />'. $menu_item->title .'</label>';

			// Menu item hidden fields
			$output .= '<input type="hidden" class="menu-item-db-id" value="0" />';
			$output .= '<input type="hidden" class="menu-item-object-id" value="'. esc_attr( $menu_item->object_id ) .'" />';
			$output .= '<input type="hidden" class="menu-item-parent-id" value="'. esc_attr( $menu_item->parent_id ) .'" />';
			$output .= '<input type="hidden" class="menu-item-type" value="'. esc_attr( $menu_item->type ) .'" />';
			$output .= '<input type="hidden" class="menu-item-append" value="'. esc_attr( $menu_item->append ) .'" />';
			$output .= '<input type="hidden" class="menu-item-title" value="'. esc_attr( $menu_item->title ) .'" />';
			$output .= '<input type="hidden" class="menu-item-url" value="'. esc_attr( $menu_item->url ) .'" />';
			$output .= '<input type="hidden" class="menu-item-append" value="'. esc_attr( $menu_item->append ) .'" />';
			break;
	}

	return $output;
}
?>