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custom_nav.php

<?php

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

/**
 * Description of exp_menu
 *
 * @author oem
 */
class Own_Exp_Menu extends Walker_Nav_Menu {

	/**
	 * @see Walker::$tree_type
	 * @since 3.0.0
	 * @var string
	 */
	var $tree_type = array( 'post_type', 'taxonomy', 'custom' );

	/**
	 * @see Walker::$db_fields
	 * @since 3.0.0
	 * @todo Decouple this.
	 * @var array
	 */
	var $db_fields = array( 'parent' => 'menu_item_parent', 'id' => 'db_id' );

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

		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] );

		// Adds the 'parent' class to the current item if it has children		
		if ( !empty( $children_elements[$element->$id_field] ) ) {
			array_push( $element->classes, 'has-child' );
		}

		$cb_args = array_merge( array( &$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 );
	}

	// 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-nav',
			'nav',
			'stacked',
			'menu-depth-' . $display_depth
		);
		$class_names = implode( ' ', $classes );

		// build html
		$output .= "\n" . $indent . '<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 . ' ' . $depth . '">';
		if ( in_array( 'has-child', $item->classes ) ) {
			$output .= '<span class="sub-nav-toggle"></span>';
		}
		// 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
		);

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

}