var intervallo = null;
var layerAttivo = null;

function mostra_submenu(id){
	if(layerAttivo!=null){
		if(layerAttivo!=id){
			nascondi_submenu_submit("submenu_"+layerAttivo);
		}else{
			clearInterval(intervallo);
		}
	}
	var obj = document.getElementById("mainmenu_"+id);

	document.getElementById("submenu_"+id).style.visibility = "visible";
	//document.getElementById("submenu_"+id).style.left = (getX(obj)-((251-obj.offsetWidth)/2))+'px';
	layerAttivo = id;

	document.getElementById("mainmenu_"+id).className = 'mainmenuover';
}





//----------------------------------------------------------------------------//





function nascondi_submenu(id){
	intervallo = setInterval("nascondi_submenu_submit()", 250);
}





//----------------------------------------------------------------------------//





function nascondi_submenu_submit(){
		document.getElementById("submenu_"+layerAttivo).style.visibility = "hidden";
		document.getElementById("mainmenu_"+layerAttivo).className = 'mainmenulink';
		clearInterval(intervallo);
}





//----------------------------------------------------------------------------//





function getX(obj){
	var x = 0;
	do
	{
		x += obj.offsetLeft;
		obj = obj.offsetParent;
	}
	while (obj);
	return x;
}





//----------------------------------------------------------------------------//





function getY(obj){
	var y = 0;
	do
	{
		y += obj.offsetTop;
		obj = obj.offsetParent;
	}
	while (obj);
	return y;
}





//----------------------------------------------------------------------------//





function getElementWidth(Elem) {
	if (ns4) {
		var elem = getObjNN4(document, Elem);
		return elem.clip.width;
	} else {
		if(document.getElementById) {
			var elem = document.getElementById(Elem);
		} else if (document.all){
			var elem = document.all[Elem];
		}
		if (op5) {
			xPos = elem.style.pixelWidth;
		} else {
			xPos = elem.offsetWidth;
		}
		return xPos;
	}
}