wp-duckbehaviorjournal/class-wp-bootstrap-navwalker.php

<?php

/**
 * WP_Bootstrap_Navwalker class.
 *
 * @extends Walker_Nav_Menu
 */
class WP_Bootstrap_Navwalker extends Walker_Nav_Menu
{

    // Add classes to ul sub-menus
    function start_lvl(&$output, $depth = 0, $args = array())
    {
        $indent = str_repeat("\t", $depth);
        $output .= "\n$indent<ul class=\"dropdown-menu\">\n";
    }

    // Add main/sub classes to li's and links
    function start_el(&$output, $item, $depth = 0, $args = array(), $id = 0)
    {
        $indent = ($depth) ? str_repeat("\t", $depth) : '';
    
        $li_attributes = '';
        $class_names = $value = '';
    
        $classes = empty($item->classes) ? array() : (array) $item->classes;
        $classes[] = (isset($args->walker) && $args->walker->has_children) ? 'dropdown' : '';
        $classes[] = 'nav-item';
        $classes[] = 'nav-item-' . $item->ID;
        if ($depth && isset($args->walker) && $args->walker->has_children) {
            $classes[] = 'dropdown-submenu';
        }
    
        $class_names = join(' ', apply_filters('nav_menu_css_class', array_filter($classes), $item, $args));
        $class_names = ' class="' . esc_attr($class_names) . '"';
    
        $id = apply_filters('nav_menu_item_id', 'nav-menu-item-' . $item->ID, $item, $args);
        $id = $id ? ' id="' . esc_attr($id) . '"' : '';
    
        $output .= $indent . '<li' . $id . $value . $class_names . $li_attributes . '>';
    
        $attributes = !empty($item->attr_title) ? ' title="'  . esc_attr($item->attr_title) . '"' : '';
        $attributes .= !empty($item->target)     ? ' target="' . esc_attr($item->target) . '"' : '';
        $attributes .= !empty($item->xfn)        ? ' rel="'    . esc_attr($item->xfn) . '"' : '';
        $attributes .= !empty($item->url)        ? ' href="'   . esc_attr($item->url) . '"' : '';
    
        $attributes .= (isset($args->walker) && $args->walker->has_children) ? ' class="nav-link dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"' : ' class="nav-link"';
    
        $item_output = isset($args->before) ? $args->before : '';
        $item_output .= '<a' . $attributes . '>';
        $item_output .= (isset($args->link_before) ? $args->link_before : '') . apply_filters('the_title', $item->title, $item->ID) . (isset($args->link_after) ? $args->link_after : '');
        $item_output .= '</a>';
        $item_output .= isset($args->after) ? $args->after : '';
    
        $output .= apply_filters('walker_nav_menu_start_el', $item_output, $item, $depth, $args);
    }
}

/**
 * Register Custom Navigation Walker
 */
function register_navwalker()
{
    require_once get_template_directory() . '/class-wp-bootstrap-navwalker.php';
}
add_action('after_setup_theme', 'register_navwalker');