Swf to swf loading

1

Im working on learning AS3 and I have come up with a button that when clicked begins a preloader animation that once completed will import a swf onto the stage. What im needing to know is how can I use this functionality but once the preloader has loaded it plays the exit animation of the current swf im in then loads the new swf that the button was targeted to? example link of what im trying to accomplish is here…costumize.me…my code is below: Im also attaching the file for you to view. Thanks in advance!

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import flash.events.*;
import flash.display.Loader;
import flash.net.URLRequest;
import flash.display.MovieClip;

function btn1Over(event:MouseEvent):void
{
btn1.gotoAndPlay(“over”);
}

function btn1Out(event:MouseEvent):void
{
btn1.gotoAndPlay(“out”);
}

function btn1Click(event:MouseEvent):void
{
loader.load(new URLRequest(“section1.swf”));
}

function trackProgress(event:ProgressEvent):void
{
var perLoaded:Number = Math.round(event.bytesLoaded / event.bytesTotal * 100);
prog_mc.gotoAndStop(perLoaded);
}

var loader:Loader = new Loader();
addChild(loader);
loader.mask = mask_mc;
btn1.buttonMode = true;
btn1.addEventListener(MouseEvent.ROLL_OVER, btn1Over);
btn1.addEventListener(MouseEvent.ROLL_OUT, btn1Out);
btn1.addEventListener(MouseEvent.CLICK, btn1Click);
loader.contentLoaderInfo.addEventListener(Progress Event.PROGRESS, trackProgress);

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