Example implementation of an AngularJS state service

nsfw.js

angular.module('app.services')
  .factory('Nsfw', function ($rootScope) {
    'use strict';
    var _nsfw = false;

    var broadcastNsfw = function (nsfw) {
      $rootScope.$broadcast('Nsfw.Update', nsfw);
    };

    var toggleNsfw = function () {
      _nsfw = !_nsfw;
      broadcastNsfw(_nsfw);
    };

    return {
      toggleNsfw: toggleNsfw,
      nsfw: _nsfw
    };
  });