Submenu Shortcode with Menu ID
##Purpose Allows admins to manually choose which submenu to display when using the [submenu] shortcode. Useful when combined with widget logic to display a sidebar menu on pages/archives/templates not in the main navigation.It's also helpful when you need to show a non-default sidebar menu for a specific template.
##Installation
The code is meant to completely replace the original submenu plugin code (dac-sidebar-menus.php
).It doesn't change the default behavior, it just allows the submenu shortcode to accept a menu_id
parameter.
##Use
Enter the ID of the submenu you want to display: [submenu menu_id='2789']
To find the menu ID, inspect the main menu. The menu ID is the four digit number following "menu-item-": <li id="menu-item-2345">About</li>
<?php
/*
Plugin Name: Design Action - Sidebar Menus
Description: Creates submenus (for use in sidebars) based on the primary menu, including active states, etc. Use with the shortcode [submenu] (within a widget) or theme function display_the_submenu();
Version: 0.0.1
Author: Design Action
Author URI: http://designaction.org
*/
defined( 'ABSPATH' ) or die( 'No script kiddies please!' );
// add hook
add_filter( 'wp_nav_menu_objects', 'my_wp_nav_menu_objects_sub_menu', 10, 2 );
// filter_hook function to react on sub_menu flag
function my_wp_nav_menu_objects_sub_menu( $sorted_menu_items, $args ) {
if ( isset( $args->sub_menu ) ) {
$root_id = 0;
// find the current menu item
foreach ( $sorted_menu_items as $menu_item ) {
if ( $menu_item->current ) {
// set the root id based on whether the current menu item has a parent or not
$root_id = ( $menu_item->menu_item_parent ) ? $menu_item->menu_item_parent : $menu_item->ID;
break;
}
}
//override menu id if 'menu_id' parameter is specified in shortcode
if ($args->manual_menu_id != '') {
$root_id = $args->manual_menu_id;
}
// find the top level parent
if ( ! isset( $args->direct_parent ) ) {
$prev_root_id = $root_id;
while ( $prev_root_id != 0 ) {
foreach ( $sorted_menu_items as $menu_item ) {
if ( $menu_item->ID == $prev_root_id ) {
$prev_root_id = $menu_item->menu_item_parent;
// don't set the root_id to 0 if we've reached the top of the menu
if ( $prev_root_id != 0 ) $root_id = $menu_item->menu_item_parent;
break;
}
}
}
}
$menu_item_parents = array();
foreach ( $sorted_menu_items as $key => $item ) {
// init menu_item_parents
if ( $item->ID == $root_id ) $menu_item_parents[] = $item->ID;
if ( in_array( $item->menu_item_parent, $menu_item_parents ) ) {
// part of sub-tree: keep!
$menu_item_parents[] = $item->ID;
} else if ( ! ( isset( $args->show_parent ) && in_array( $item->ID, $menu_item_parents ) ) ) {
// not part of sub-tree: away with it!
unset( $sorted_menu_items[$key] );
}
}
return $sorted_menu_items;
} else {
return $sorted_menu_items;
}
}
function display_the_submenu($atts) {
//set menu_id default
$a = shortcode_atts( array(
'menu_id' => ''
), $atts );
return wp_nav_menu( array(
'theme_location' => 'primary-menu',
'sub_menu' => true,
'show_parent' => true,
'direct_parent' => false,
'echo' => false,
'manual_menu_id' => $a['menu_id']
) );
}
// Register Shortcodes
function register_shortcodes(){
add_shortcode('submenu', 'display_the_submenu');
}
add_action( 'init', 'register_shortcodes');