menu_item_parent && $item->menu_item_parent > 0 ) { $parents[] = $item->menu_item_parent; } } foreach ( $items as $item ) { if ( in_array( $item->ID, $parents ) ) { //Add "dropdown" class to parents $item->classes[] = 'dropdown'; } } return $items; } //add_menu_parent_class to menu add_filter( 'wp_nav_menu_objects', 'boston_business_pro_add_menu_parent_class' ); function boston_business_pro_new_submenu_class($menu) { $menu = preg_replace('/ class="sub-menu"/','/ class="dropdown-menu" /',$menu); return $menu; } add_filter('wp_nav_menu','boston_business_pro_new_submenu_class');