Angular.js autoscroll directive.

angular-autoscroll.js

angular.module("autoscroll", [])
  .service("scroller", function() {
    this.defaultTime = 500;
    
    this.scroll = function(element, height, time) {
      element.animate({
        scrollTop: height
      }, time || this.defaultTime);
    }
    
    this.scrollUp = function(element, time) {
      this.scroll(element, 0, time);
    }
    
    this.scrollDown = function(element, time) {
      this.scroll(element, element.prop("scrollHeight"), time);
    }
  })

  .directive("autoScroll", ["$timeout", "scroller", function($timeout, scroller) {
    return function(scope, element, attrs) {
      var direction = attrs.autoScroll;
      
      scope.$watch(function() {
        return element.children().length;
      }, function() {
        switch(direction) {
          case "up":
            scroller.scrollUp(element, 500); 
            break;
            
          case "down": 
            scroller.scrollDown(element, 500); 
            break;
            
          default: 
            throw "You must specify an 'up' or 'down' autoscroll direction.";
        }
      });
    }
  }]);