WordPress multisite sharing menu having working current_menu_item class

Have fixed this problem by added a new class “current-site” on the menu.

<?php
            $blogs = get_sites();
            $current_site = get_current_blog_id();
            foreach( $blogs as $b ){
                //$b->blog_id)
                switch_to_blog($b->blog_id);
                if($current_site == $b->blog_id){
                    wp_nav_menu(array(
                        'theme_location'=>'primary_menu',
                        'menu_class'=>'navbar current-site',
                        'container' => false,
                        'link_before' => '<span class="menu-wrap">',
                        'link_after'=>'</span>',
                        'fallback_cb'    => false,
                        'walker' => new Walker_Nav_Pointers(),
                    )); 
                } else {
                    wp_nav_menu(array(
                        'theme_location'=>'primary_menu',
                        'menu_class'=>'navbar',
                        'container' => false,
                        'link_before' => '<span class="menu-wrap">',
                        'link_after'=>'</span>',
                        'fallback_cb'    => false,
                        'walker' => new Walker_Nav_Pointers(),
                    )); 
                }
                restore_current_blog();
            }  

        ?>