function displayLayer(id, show){
	obj = document.getElementById(id);
	if(show){
		obj.style.display = "";
	} else {
		obj.style.display = "none";	
	}
}

if(top.location != location) {
	top.location.href = document.location.href;
}

// geef in de functie togglebox de naam van de id van het element wat je wilt laten zien/verdwijnen
function toggleBox(obj){
	xObj = document.getElementById(obj);
	if(xObj.style.display == "none"){
	   xObj.style.display = "";
	} else {
	   xObj.style.display = "none";		
	}
}

// select menu locatie switcher - zet op onchange changeLocation(this) - zet in de value's de uri waar je naar linkt
function changeLocation(menuObj){
	var i = menuObj.selectedIndex;
	window.location = menuObj.options[i].value;
}

if (top.location != location)
	top.location.href = document.location.href;

function toggle(id){
	obj = document.getElementById(id);
	if (obj.style.display == 'none')
		obj.style.display = '';
	else
		obj.style.display = 'none';
}

// dit is een stukje javascript van erik
function closeMessage(){
	document.getElementById("message_container").style.display  = "none";
}
function closeError(){
	document.getElementById("error_container").style.display  = "none";
}
function getImageWidth() {
	return document.getElementById("image").offsetWidth;
}

function imageLoaded() {
	document.getElementById("image").onload=null;	
	
	document.getElementById("image_content").style.width  = getImageWidth()+"px";	
	document.getElementById("message").style.width  = getImageWidth()+"px";
	
//	var outerBox = document.getElementById("error_w");
//	var innerBox = document.getElementById("error_w2");

	var outerBox = document.getElementById("image_w");
	var innerBox = document.getElementById("image_w2");

	var initialHeight = outerBox.offsetHeight;
	var documentHeight = document.body.offsetHeight;
	var windowHeight = document.body.clientHeight;
	var minimumHeight = (documentHeight > windowHeight) ? documentHeight : windowHeight;
	if(initialHeight < minimumHeight) {
		outerBox.style.height = minimumHeight;
		innerBox.style.height = minimumHeight;
	}
}

function openImage(imageUrl/*,imageNumber*/){

	document.getElementById("image_content").style.width  = "640px";	
	document.getElementById("message").style.width  = "640px";

	document.getElementById("image_container").style.display  	= "";
	document.getElementById("image").onload = imageLoaded;
	document.getElementById("image").src  = imageUrl;
}

function closeImage(){
	document.getElementById("image_container").style.display  = "none";
	document.getElementById("image").src  = "/image/studentstyle/spacer.gif";
	document.getElementById("image_content").style.width  = "640px";	
	document.getElementById("message").style.width  = "640px";	
}