More Scrolling Function in Flash 5 - Page 11

Take a look at one of the cfb_logic loops and you'll see why:

Let's check out line 2 of the code first. All that this "setProperty" action does is change the _y (vertical) value of scroll_shape to its current value minus 1 pixel. Since the updated value will be 1 pixel less than the previous value, scroll_shape will move up along the _y axis (remember scrolling down increases the _y value of scroll_shape). Here's the trick though; all this action does is move scroll_shape, and it doesn't DIRECTLY affect var_mc. However, since the scroll button's "on (press)" handler triggers the (scroll_)logic loop in addition this cfb_logic, loop, the drag loop will move var_mc for us. This is what I meant by harnessing the power of the ActionScript we already have written.