External http request in fiori Custom Applications

Hello,

I am facing issues in calling external http request from custom fiori application.

Code written for calling external service is as follows.

var url = "any external url";
var xmlhttp = new XMLHttpRequest();
xmlhttp.open("GET", url , true);
xmlhttp.send();
xmlhttp.onreadystatechange=function() {     if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {          alert("success")     }
};

Help is appreciated.

Thanks and Regards

Roshan Jalgaonkar