I am trying to send request to my server from tizen web app. But it always failed. I added jquery, angularjs, TAU and other required lib in the project. what is the problem ?

Code =>>>>

  var xhr = new XMLHttpRequest();
   xhr.open('get', url, true);
   xhr.responseType = 'json';
   xhr.onload = function() {
    var status = xhr.status;
    if (status == 200) {
     
    } else {
    
    }
   };
   xhr.send();
  };