var xmlhttp

function loadBarStatus() {

    xmlhttp = GetXmlHttpObject();
    if (xmlhttp == null) {
        document.getElementById("status_note").innerHTML = "Cannot update bar status. Your browser is not supported.";
        return;
    }
    var url = "StatusCurrent.xml";
    xmlhttp.onreadystatechange = stateChanged;
    xmlhttp.open("GET", url, true);
    xmlhttp.setRequestHeader("Content-Type","text/xml");
    xmlhttp.setRequestHeader("If-Modified-Since", "Sat, 1 Jan 2005 00:00:00 GMT");
    xmlhttp.send(null);
}

function stateChanged() {
    if (xmlhttp.readyState == 4) {
        var snode = xmlhttp.responseXML.getElementsByTagName("status")[0].childNodes[0];
        document.getElementById("status").className = "status_" + snode.nodeValue;
        if (xmlhttp.responseXML.getElementsByTagName("note")[0].childNodes.length > 0) {
            var nnode = xmlhttp.responseXML.getElementsByTagName("note")[0].childNodes[0];
            document.getElementById("status_note").innerHTML = nnode.nodeValue;
        }
        else
            document.getElementById("status_note").style.display = 'none';
    }
}

function GetXmlHttpObject() {
    if (window.XMLHttpRequest) {
        // code for IE7+, Firefox, Chrome, Opera, Safari
        return new XMLHttpRequest();
    }
    if (window.ActiveXObject) {
        // code for IE6, IE5
        return new ActiveXObject("Microsoft.XMLHTTP");
    }
    return null;
}