var menu = new Array;
menu[0] = "Layer1";
menu[1] = "Layer2";
menu[2] = "Layer3";
menu[3] = "Layer4";
menu[4] = "Layer5";
menu[5] = "Layer6";
menu[6] = "Layer7";
menu[7] = "Layer8";
menu[8] = "Layer9";
menu[9] = "Layer10";
menu[10] = "Layer11";

function showMenu(n){
	var obj = eval(menu[n]);
	
	if(obj.style.visibility=="visible") return;

	obj.style.visibility="visible";

	for (i=0;i<10;i++){
		mObj = eval(menu[i]);
		if (i!=n) mObj.style.visibility="hidden";
}}

function hideMenu(n) {
	var obj = eval(menu[n]);
	obj.style.visibility="hidden";
}