<?php

/**

* Extended Walker class for use with the

* Twitter Bootstrap toolkit Dropdown menus in Wordpress.

* Edited to support n-levels submenu.

* @author johnmegahan https://gist.github.com/1597994, Emanuele 'Tex' Tessore https://gist.github.com/3765640

*/

class Bootstrap_Walker_Nav_Menu extends Walker_Nav_Menu {

function start_lvl( &$output, $depth ) {

$indent = str_repeat( "\t", $depth );

$submenu = ( $depth > 0 ) ? ' sub-menu' : '';

$output .= "\n$indent<ul class=\"dropdown-menu$submenu depth_$depth\">\n";

}

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;

// managing divider: add divider class to an element to get a divider before it.

$divider_class_position = array_search( 'divider', $classes );

if( $divider_class_position !== false ){

$output .= "<li class=\"divider\"></li>\n";

unset( $classes[$divider_class_position] );

}

$classes[] = ( is_object($args) && $args->has_children ) ? 'dropdown' : '';

$classes[] = ( $item->current || $item->current_item_ancestor ) ? 'active' : '';

$classes[] = 'menu-item-' . $item->ID;

if ( $depth && $args->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', '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 ) .'"' : '';

$attributes .= ( is_object($args) && $args->has_children ) ? ' class="disabled dropdown-toggle" data-toggle="dropdown"' : '';

$item_output = ( is_object($args) ) ? $args->before : '';

$item_output .= '<a'. $attributes .'>';

$link_before = ( is_object($args) ) ? $args->link_before : '';

$link_after = ( is_object($args) ) ? $args->link_after : '';

$item_output .= $link_before . apply_filters( 'the_title', $item->title, $item->ID ) . $link_after;

$item_output .= ( $depth == 0 && is_object($args) && $args->has_children ) ? ' <b class="caret"></b></a>' : '</a>';

$item_output .= ( is_object($args) ) ? $args->after : '';

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

}

function display_element( $element, &$children_elements, $max_depth, $depth=0, $args, &$output ) {

//v($element);

if ( !$element )

return;

$id_field = $this->db_fields['id'];

//display this element

if ( is_array( $args[0] ) )

$args[0]['has_children'] = ! empty( $children_elements[$element->$id_field] );

else if ( is_object( $args[0] ) )

$args[0]->has_children = ! empty( $children_elements[$element->$id_field] );

$cb_args = array_merge( array(&$output, $element, $depth), $args);

call_user_func_array(array(&$this, 'start_el'), $cb_args);

$id = $element->$id_field;

// descend only when the depth is right and there are childrens for this element

if ( ($max_depth == 0 || $max_depth > $depth+1 ) && isset( $children_elements[$id]) ) {

foreach( $children_elements[ $id ] as $child ){

if ( !isset($newlevel) ) {

$newlevel = true;

//start the child delimiter

$cb_args = array_merge( array(&$output, $depth), $args );

call_user_func_array( array(&$this, 'start_lvl'), $cb_args );

}

$this->display_element( $child, $children_elements, $max_depth, $depth + 1, $args, $output );

}

unset( $children_elements[ $id ] );

}

if ( isset($newlevel) && $newlevel ){

//end the child delimiter

$cb_args = array_merge( array(&$output, $depth), $args );

call_user_func_array( array(&$this, 'end_lvl'), $cb_args );

}

//end this element

$cb_args = array_merge( array(&$output, $element, $depth), $args );

call_user_func_array(array(&$this, 'end_el'), $cb_args );

}

}

?>