<script type="text/javascript" src="nav.js"></script>

<style>
/* Navigation Bar */
#menus {
	float:  left;
	width:  128px;
	padding: 	4px;
	padding-left: 24px;
	text-align: 	left;
}

.menu, #menuheader {
	margin-left: -16px;
	font-weight: bold;
}

.menuitems {
	display: 	none;
	margin-left: 24px;
	font-weight: normal;
}

.menuitem {
	text-indent: -8px;
}

.item {
	font-weight: bold;
}

.showhide {
	vertical-align: middle;
}

#naverror {
	text-align: 	left;
}
</style>

<?php
$file = 'nav.xml';
$currentMenu = '';
$currentItem = '';
$link = false;

function navStartElement($parser, $name, $attrs) {
	global $currentMenu;
	global $link;
	
	switch ($name) {
 case "MENU":
 	echo '<div id="'.$attrs['ID'].'" class="menu">';
 	echo '<img src="images/expand.gif" id="'.$attrs['ID'].'Button" width="12" height="12" onclick="toggleMenu(\''.$attrs['ID'].'\');" alt="" class="showhide" /> ';
 	
 	if ($attrs['LINK'])
  echo '<a href="'.$attrs['LINK'].'">'.$attrs['CAPTION'].'</a>';
 	else
  echo $attrs['CAPTION'];
 	
 	echo '<div id="'.$attrs['ID'].'Items" class="menuitems">';
 	
 	if ($currentMenu)
  $currentMenu = $currentMenu.';'.$attrs['ID'];
 	else
  $currentMenu = $attrs['ID'];
 	break;
 
 case "ITEM":
 	if ($currentMenu == '')
  echo '<div class="item">';
 	else
  echo '<div class="menuitem">';	
 	
 	if ($attrs['LINK']) {
  echo '<a href="'.$attrs['LINK'].'" class="menulink">';
  $link = true;
 	}
 	else
  $link = false;
 	break;
 
 case "BLANK":
 	echo '<br />';
 	break;
	}
}

function navEndElement($parser, $name) {
	global $currentMenu;
	global $link;
	
	switch ($name) {
 case "MENU":
 	echo '</div></div>';
 	$currentMenu = substr($currentMenu, 0, strpos($currentMenu, ';'));
 	break;
 case "ITEM":
 	if ($link)
  echo '</a>';
 	echo '</div>';
 	break;
	}
}

function navCharacterData($parser, $data) {
	global $currentItem;
	
	$currentItem = $data;
	echo $data;
}

$xml_parser = xml_parser_create();
xml_set_element_handler($xml_parser, "navStartElement", "navEndElement");
xml_set_character_data_handler($xml_parser, "navCharacterData");
@ $fp = fopen($file, "r");
if (!($fp))
	echo '<p id="naverror">We are unable to load the navigation menu. We apologise for the inconvenience.</p>';
else {
	while ($data = fread($fp, 4096)) {
 if (!xml_parse($xml_parser, $data, feof($fp))) {
 	printf('<p id="naverror">XML error: %s at line %d</p>',
    xml_error_string(xml_get_error_code($xml_parser)),
    xml_get_current_line_number($xml_parser));
 	break;
 }
	}
	xml_parser_free($xml_parser);
}
?>

function toggleMenu(mnu) {
	var menu = document.getElementById(mnu + "Items");
	var image = mnu + "Button";

	var expand = "images/expand.gif";
	var collapse = "images/collapse.gif";
	
	if (menu.style.display == "block") {
 menu.style.display = "none";
 swapImages(image, expand);
	}
	else {
 menu.style.display = "block";
 swapImages(image, collapse);
	}
	
	return true;
}

function swapImages(currentImage, newImagePath) {
	var image = new Image();
	image.src = newImagePath;
	
	document.getElementById(currentImage).src = image.src;
}

<?xml version="1.0" encoding="ISO-8859-1"?>

<navigation>

<item id="home" link="?">Home</item>

<menu id="mnuTest" caption="Test Menu" link="?page=test">
	<menu id="mnuTestSub" caption="Submenu">
 <item link="?">Submenu Item 1</item>
 <item>Submenu Item 2</item>
 <item>Submenu Item 3</item>
	</menu>
	<item>Menu Item 1</item>
	<item link="?page=boo">Menu Item 2</item>
	<item>Menu Item 3</item>
</menu>

</navigation>