Ionicframework: return status 0 calling http get service

I'm calling a simple method on click simple button. My alert print status 0 (i think that it is a cors problem, but if i run the app on Ionic-View it works fine, and if i run it con browser using ionic serve command it works fine).

this is my call:

$http.get(url, {
  headers: {
    'Content-Type': 'application/x-www-form-urlencoded'
  }
}).success(function(data) {
  alert(data);
}).error(function(data, status) {
  alert(data + status);
});

Any ideas?