function show(){
var title = "new version"
, options = {
body: "user can download files from site!",
icon: "http://bootsnipp.com/img/avatars/80371038613994cd96537912756058cb63fd6adb.jpg"
};
if (!("Notification" in window)) {
alert("This browser does not support desktop notification");
}
else if (Notification.permission === "granted") {
var n = new Notification(title, options);
n.onshow=function(){
setTimeout(n.close.bind(n), 2000);
}
n.onclick = function () {
n.close();
};
}
else if (Notification.permission !== 'denied') {
Notification.requestPermission(function (permission) {
if (permission === "granted") {
var n = new Notification(title, options);
}
});
}
}