<?php
$defaults = array(
‘theme_location’ => ”,
‘menu’ => ‘Header Menu’,
‘menu_id’ => ”,
‘echo’ => true,
‘fallback_cb’ => ”,
‘items_wrap’ => ‘<ul class=”list-inline”>%3$s</ul>’,
‘depth’ => 0,
‘walker’ => new inner_sub_menu
);
wp_nav_menu( $defaults );
?>
<?php
class inner_sub_menu extends Walker_Nav_Menu {

// add classes to ul sub-menus
function start_lvl( &$output, $depth ) {
// depth dependent classes
$indent = ( $depth > 0 ? str_repeat( “\t”, $depth ) : ” ); // code indent
$display_depth = ( $depth + 1); // because it counts the first submenu as 0
$classes = array(‘sub-menu list-unstyled’);
$class_names = implode( ‘ ‘, $classes );
// build html
$output .= “\n” . $indent . ‘<div class=”dropdown-menu”><ul class=”‘ . $class_names . ‘”>’ . “\n”;
}
// add main/sub classes to li’s and links
function start_el( &$output, $item, $depth, $args ) {
global $wp_query;
$indent = ( $depth > 0 ? str_repeat( “\t”, $depth ) : ” ); // code indent

// depth dependent classes
$depth_classes = array(
( $depth == 0 ? ‘main-menu-item’ : ‘sub-menu-item’ ),
( $depth >=2 ? ‘sub-sub-menu-item’ : ” ),
( $depth % 2 ? ‘menu-item-odd’ : ‘menu-item-even’ ),
‘menu-item-depth-‘ . $depth
);
$depth_class_names = esc_attr( implode( ‘ ‘, $depth_classes ) );

// passed classes
$classes = empty( $item->classes ) ? array() : (array) $item->classes;
$class_names = esc_attr( implode( ‘ ‘, apply_filters( ‘nav_menu_css_class’, array_filter( $classes ), $item ) ) );

// build html
$output .= $indent . ‘<li id=”nav-menu-item-‘. $item->ID . ‘” class=”‘ . $depth_class_names . ‘ ‘ . $class_names . ‘”>’;

// link 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 .= ‘ class=”menu-link ‘ . ( $depth > 0 ? ‘sub-menu-link’ : ‘main-menu-link’ ) . ‘”‘;

$item_output = sprintf( ‘%1$s<a%2$s>%3$s%4$s%5$s</a>%6$s’,
$args->before,
$attributes,
$args->link_before,
apply_filters( ‘the_title’, $item->title, $item->ID ),
$args->link_after,
$args->after
);
$output .= apply_filters( ‘walker_nav_menu_start_el’, $item_output, $item, $depth, $args );
}
}
?>