document.getById = function(strid) {
	if (document.getElementById)
		return document.getElementById(strid);
	else if (document.all)
		return document.all[strid];
	else if (document[strid])
		return document[strid];
	else if (document.layers && document.layers[strid])
		return document.layers[strid];
	return null;
}

var arr_menus = new Array('menu0', 'menu1');

function showMenu(menuId) {
	for (var i = 0; i < arr_menus.length; ++i) {
		if (menuId != arr_menus[i]) {
			hideMenu(arr_menus[i]);
		}
	}
	
	var obMenu = document.getById(menuId);
	if (obMenu) {
		if (obMenu.timer) {
			clearTimeout(obMenu.timer);
			obMenu.timer = null;
		}
		
		obMenu.style.visibility = 'visible';
	}
}

function hideMenu(menuId) {
	
	var obMenu = document.getById(menuId);
	if (obMenu) {
		if (obMenu.timer) {
			obMenu.timer = null;
		}
		obMenu.style.visibility = 'hidden';
	}
}

function timeoutHideMenu(menuId) {
	var obMenu = document.getById(menuId);
	if (obMenu) {
		obMenu.timer = setTimeout("hideMenu('" + menuId + "');", 200);
	}
}