LanguagesEvent($rootScope, LANG_EVENTS) {
  return {
    changeLanguage: function changeLanguage(langKey) {
      $rootScope.$emit(LANG_EVENTS.changeLanguage,langKey);
    },
    onChangeLanguage: function onChangeLanguage(scope, handler) {
      var deRegistration = $rootScope.$on(LANG_EVENTS.changeLanguage, function(event, langKey) {
        handler(langKey);
      });
      scope.$on('$destroy', function() {
         deRegistration();
      });
      return deRegistration;
    }
  };
}