wp nav walker

header-navbar.php

<?php
/**
 * Top navigation and branding
 */
?>
<!-- <div class="utilsbar">
  <div class="container">
    some info here
  </div>
</div> -->
<header id="masthead" class="navbar navbar-default navbar-fixed-top">
  <div class="container">
    <div class="navbar-header">
      <button class="navbar-toggle collapsed" type="button" title="Rozwiń menu" data-toggle="collapse" data-target="#nav-main" aria-expanded="false" aria-controls="nav-main">
        <span class="sr-only">Menu</span>
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>
      </button>
      <h1>
        <a href="<?php echo esc_url( home_url( '/' ) ); ?>" class="navbar-brand" title="<?php bloginfo( 'name' ); ?>">
        <?php
          if ( has_custom_logo() ) {
            $custom_logo_id = get_theme_mod( 'custom_logo' );
            $custom_logo = wp_get_attachment_image_src( $custom_logo_id , 'full' );
            echo '<img src="'. esc_url( $custom_logo[0] ) .'" alt="'. get_bloginfo( 'name' ) .'" />';
          } else {
            bloginfo( 'name' );
          }
        ?>
        </a>
      </h1>
    </div>
    <?php wp_nav_menu( array(
      'menu'            => 'primary',
  		'theme_location'  => 'primary',
      'depth'           => 2,
  		'menu_id'         => 'nav-main-list',
      'menu_class'      => 'nav navbar-nav',
      'container'       => 'nav',
      'container_class' => 'navbar-collapse navbar-right collapse',
      'container_id'    => 'nav-main',
      'walker'          => new Startertheme_Primary_Nav_Walker()
      // 'fallback_cb'     => 'WP_Bootstrap_Navwalker::fallback',
      // 'walker'          => new WP_Bootstrap_Navwalker()
  	) ); ?>
  </div>
</header>

info.md

Classes used for various options:

1. .ni_<icon-prefix> - glyphicon/fa (first icon class)
2. .ni_<icon-name> - glyphicon-whatever (second icon class)
3. ni_hidetext - generate <span class="sr-only">Something</span>
4. ni_disabled

walker.php

<?php
/**
 * WP Custom Nav Walker
 */

if (!class_exists('Startertheme_Primary_Nav_Walker')) {

  class Startertheme_Primary_Nav_Walker extends Walker_Nav_Menu {

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

    function start_el(&$output, $item, $depth = 0, $args = array(), $id = 0) {
      $indent = ($depth) ? str_repeat("\t", $depth) : '';
      $li_attributes = '';
      $value = '';
      $class_names = $value;
      $classes = empty($item->classes) ? array() : (array) $item->classes;

      if (in_array("ni_hidetext", $classes)) {
        $srOpen = '<span class="sr-only">';
        $srClose = '</span>';
      } else {
        $srOpen = $srClose = '';
      }

      if (in_array("ni_disabled", $classes)) {
        $classes[] = 'disabled';
      }

      $navItemOptions = array_filter($classes, function($var) {
        $pat = '/^ni_/i';
        return preg_match($pat, $var);
      });

      $navItemIcon = '';
      if (!empty($navItemOptions)) {
        $classes = array_diff($classes, $navItemOptions); // remove unnecessary classes from `li`

        $navItemIconClasses = array_filter($navItemOptions, function($var) {
          $pat = '/^ni_(?!hidetext|disabled)/i';
          return preg_match($pat, $var);
        });

        if (!empty($navItemIconClasses)) {
          $navItemIcon = '<i class="' . str_replace('ni_', '', join(' ', $navItemIconClasses)) . '" aria-hidden="true"></i> ';
        }
      }

      $class_names = join(' ', apply_filters('nav_menu_css_class', array_filter($classes), $item, $args));
      if ($args->walker->has_children) {$class_names .= ' dropdown';}
      if ($item->current || $item->current_item_ancestor) {$class_names .= ' active';}

      $class_names = $class_names ? ' class="' . esc_attr($class_names) . '"' : '';
      $id = apply_filters('nav_menu_item_id', 'menu-item-'.$item->ID, $item, $args);
  		$id = strlen($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) . '"' : '';

      $attributes .= ($args->walker->has_children) ? ' class="dropdown-toggle" data-toggle="dropdown" aria-haspopup="true"' : '';

      $item_output = $args->before;
  		$item_output .= '<a' . $attributes . '>' . $navItemIcon . $srOpen;
  		$item_output .= $args->link_before . apply_filters('the_title', $item->title, $item->ID) . $args->link_after;
  		$item_output .= ($depth === 0 && $args->walker->has_children) ? $srClose . ' <i class="glyphicon glyphicon-menu-down" aria-hidden="true"></i></a>' : $srClose . '</a>';
  		$item_output .= $args->after;

  		$output .= apply_filters('walker_nav_menu_start_el', $item_output, $item, $depth, $args);
    }

    // function end_el() {
    //
    // }

    // function end_lvl() {
    //
    // }

  }

}