Bootstrap navbar menu with dropdowns in WP

Hello, I want to have a Bootstrap navbar with dropdowns. I read here that “Smart menu only work with single level menus” and “One of the most noticeable functionality change in Bootstrap 3.0.0+ is that it only supports a single dropdown level.”

My question: is there a way to use Bootstrap navbar with dropdown for WP in PG?
And if so, what is the way? Many thanks

Ok, I’m too much a newbie I believe.
I try to have a walker as Matjazt recommends . As I realized that my navbar menu as one single dropdown level.
I did add wp_smart_navwalker.php to root, then I add a PHP in the tree. But now I’m lost with what to do next? And I don’t understand Tell the walker which layout to use for menu items by assigning the template to PG_Smart_Walker_Nav_Menu::$options[‘template’] before calling wp_nav_menu.
In short I will appreciate some help or guidance, if you know how to do it. Many thanks

and I add the line ```
require_once “wp_smart_navwalker.php”;