read file from xhr and write on system

gistfile1.js

var xhr = Titanium.Network.createHTTPClient();
xhr.open("GET","http://www.yourdomain.com/test.txt");
xhr.onload = function(){

    statusCode = xhr.status;
    if(statusCode == 200)
    {
        var doc = this.responseText;
        var f = Titanium.Filesystem.getFile(Titanium.Filesystem.applicationDataDirectory,'test.txt');
        f.write(doc);
    }
 
};
xhr.send();

var f = Titanium.Filesystem.getFile(Titanium.Filesystem.applicationDataDirectory, 'test.txt');
 
var contents = f.read();