/*************************/
function offset(elem) {
	if(!elem) elem = this;

	var x = elem.offsetLeft;
	var y = elem.offsetTop;

	while (elem = elem.offsetParent) {
		x += elem.offsetLeft;
		y += elem.offsetTop;
	}

	return { left: x, top: y };
}

/*************************/
function afficher_menu(id, action)
	{
	var menu = document.getElementById('Menu_'+id);
	var barre = document.getElementById('Barre_'+id);

	var x=offset(menu).left-17;
	var y=(offset(menu).top+menu.offsetHeight+2);
	
	if((offset(barre).left != offset(menu).left ) || (offset(barre).top != y))
		{
		barre.style.left = x+'px';
		barre.style.top = y+'px';
		}
		
	if(action==true)
		barre.style.visibility='visible';
	else
		barre.style.visibility='hidden';
	}