var http_request = false;
var URL
function makeRequest(URL, alertFunction) {
    if (window.XMLHttpRequest) { // Mozilla, Safari, ...
        http_request = new XMLHttpRequest()
    } else if (window.ActiveXObject) { // IE
        try {
            http_request = new ActiveXObject("Msxml2.XMLHTTP")
        } catch (e) {
            try {
                http_request = new ActiveXObject("Microsoft.XMLHTTP")
            } catch (e) {}
        }
    }
    if (!http_request) {
        alert('Giving up :( Cannot create an XMLHTTP instance')
        return false
    }
    http_request.onreadystatechange = function() {alertFunction(http_request)}
    http_request.open('GET', URL, true)
    http_request.send(null)
    return true
}

var alertContents = function (http_local_request) {
    if ( (http_local_request.readyState == 4)||(http_local_request.readyState=="complete") ) {
        if (http_local_request.status == 200) {
    		document.getElementById('liste_comment').innerHTML = http_local_request.responseText
        } else {
            alert('There was a problem with the request: '+URL+', '+http_local_request.status)
    	}
    }
}
function listeComment(video_id,cat) {
	var theliste_listeComment = document.getElementById('liste_comment'); // the UL
	
	// switch UL with a loading div
	theliste_listeComment.innerHTML = '<div class="loading"></div>';
	x = makeRequest('ajax_liste_comment.php?video_id='+escape(video_id)+'&cat='+escape(cat), alertContents)
	// On return, call alertContent() to display returned value
}