Based on http://jsfiddle.net/niden/86L5p/

angular_loading_indicator.js

angular.module('LoadingIndicator', [])
.config(['$httpProvider', function ($httpProvider) {

  var startLoadingIndicator = function() {
    angular.element('.loading').text('Loading ...');
  };

  $httpProvider.responseInterceptors.push('HttpLoadingInterceptor');
  $httpProvider.defaults.transformRequest.push(function (data, headersGetter) {
    // On request start
    startLoadingIndicator();
    return data;
  });
}])

.factory('HttpLoadingInterceptor', ['$q', '$window', function ($q, $window) {

  var stopLoadingIndicator = function() {
    angular.element('.loading').text('Done ...');
  };

  return function (promise) {
    return promise.then(function (response) {
      // On success
      stopLoadingIndicator();
      return response;
    }, function (response) {
      // On error
      stopLoadingIndicator();
      return $q.reject(response);
    });
  };
}]);