function showMenu(objectID){
	var menu = "menu_" + objectID.substring(9);
	var i = 1;
	while(document.getElementById('hoofdcat_' + i) != null) {
		document.getElementById('hoofdcat_' + i).style.visibility="hidden";
		document.getElementById('menu_' + i).style.background="#DCEEBB";
		i++;
	}
	document.getElementById(menu).style.background="#BBDD99";
	document.getElementById(objectID).style.visibility="visible";

}

function showBottomMenu(objectID){
	bottomHideAll();
	document.getElementById(objectID).style.visibility="visible";
	document.getElementById("popupmenu_spacer").style.visibility="visible";
}
function bottomHideAll(){
	document.getElementById('a').style.visibility="hidden";
	document.getElementById('b').style.visibility="hidden";
	
	document.getElementById("popupmenu_spacer").style.visibility="hidden";
}

function openVenster(pagina) {
	mywindow = window.open (pagina, "mywindow","location=0,status=0,scrollbars=1,resizable=1,height=550,width=750");
	mywindow.focus();
}

function openKleinVenster(pagina) {
	smallwindow = window.open (pagina, "smallwindow","location=0,status=0,scrollbars=1,width=450,height=400");
	smallwindow.focus();
}