Scroller service for Angular

Scroller.js

(function() {
  'use strict';
  angular.module('ngExtensionsApp')
  .factory('Scroll', function($window, $timeout) {
    var wait = 100,
      callbacks = [],
      timeout_identifier = null;

    function onScroll(event) {
      $timeout.cancel(timeout_identifier);
      timeout_identifier = $timeout(function() {
        callbacks.forEach(function(cb) {
          cb(event);
        });
      }, wait);
    };

    $window.onscroll = onScroll;

    return function(cb) {
      callbacks.push(cb);
    };
  });

}());