Nav Menu section for adding links to other blogs on network

blog-home-links.php

<?php
/*
 * Plugin Name: Site Home Links
 * Plugin URI:
 * Description:
 * Version:
 * Author: Kailey Lampert
 * Author URI: kaileylampert.com
 * License: GPLv2 or later
 * License URI: http://www.gnu.org/licenses/gpl-2.0.html
 * TextDomain: site-home-links
 * DomainPath:
 * Network:
 */

$site_home_links = new Site_Home_Links();

class Site_Home_Links {

	function __construct() {
		if ( ! is_multisite() ) return;
		add_action( 'admin_init', array( &$this, 'admin_init' ) );
		add_action( 'admin_footer-nav-menus.php', array( &$this, 'admin_footer' ) );
	}

	function admin_init() {
		add_meta_box( 'site_home_links', __( 'Site Links', 'site-home-links' ), array( &$this, 'add_meta_box' ), 'nav-menus', 'side', 'low' );
	}

	function add_meta_box() {
			echo '<ul id="site_home_links">';

			$list_key = 'site_list_cache';
			if ( false === ( $list = get_site_transient( $list_key ) ) ) {
				$list = '';
				foreach( wp_get_sites() as $site ) {
					switch_to_blog( $site['blog_id'] );
					$home = home_url();
					$title = get_bloginfo();
					$list .= "<li><label><input class='site-home-link' type='checkbox' value='$home' /><input type='hidden' value='{$title}' /> {$title}</label></li>";
					restore_current_blog();
				}
				set_site_transient( $list_key, $list, 60*60*24*7 );
			}
			echo $list;

			echo '</ul>';
			?><p class="button-controls">
				<span class="list-controls">
					<a href="#" class="select-all-site-home-links"><?php _e('Select All', 'site-home-links' ); ?></a>
				</span>
				<span class="add-to-menu">
					<input type="submit" class="button-secondary submit-add-to-menu right" value="<?php esc_attr_e('Add to Menu', 'site-home-links' ); ?>" id="submit-site-home-links" />
					<span class="spinner"></span>
				</span>
			</p><?php
	}

	function admin_footer() {
		?><script>
		jQuery('.select-all-site-home-links').click( function(ev) {
			ev.preventDefault();
			checked = jQuery('.site-home-link:checked');
			all = jQuery('.site-home-link');
			//if all are checked, uncheck
			if ( checked.length == all.length )
				jQuery('.site-home-link').click();
			//otherwise just check the unchecked
			else
				jQuery('.site-home-link:not(:checked)').click();
		});
		jQuery('#submit-site-home-links').click( function(ev) {
			ev.preventDefault();
			jQuery('.site-home-link:checked').each( function() {
				url = jQuery(this).val();
				label = jQuery(this).next().val();
				wpNavMenu.addLinkToMenu( url, label, wpNavMenu.addMenuItemToBottom, function() {} );
			});
		});
		</script><?php
	}

}