Before and after question

[joenowhere]

I'm new in Flash, now I want to make a before and after photo gallery, and each set of photo have a bar in it, so user can click on the bar and slide left and right to see the effect before and after, but the problem is I only know the AC for moving the bar but not with the mask, so did any one know how to make the mask move with the bar? Thanks a lot!

Below is the code I have and the SWF file, please help and thanks!

slider_mc.addEventListener(MouseEvent.MOUSE_DOWN, drag);
stage.addEventListener(MouseEvent.MOUSE_UP, drop);

function drag(e:MouseEvent):void
{
     e.target.startDrag(false, new Rectangle(0,300,800,0));
}

function drop(e:MouseEvent):void
{
     stopDrag();
}

http://www.4shared.com/document/HgJS...and_After.html

[dougcollins02]

I think that perhaps an easy way to do this would be to place the "before" graphic over the "after" graphic and just have the slider control the "before" image alpha. Here's a good example of how that works: http://www.flashandmath.com/howtos/sliderstepper/