Flex4 preloader: cannot change stageWidth and stageHeight to anything but defaults?

Question

I've made a class to extend SparkDownloadProgressBar and added it to the the preloader="" mxml in the <s:Application> tag. the flash object width and height in the html is set to 100%, as well as in the <s:Application> tag. No matter what i set in the application, i can't get the stageWidth and srtageHeight set to anything but the defauts: 500x375. any ideas? here's my code for the SparkDownloadProgressBar class:
package components
    import com.greensock.TweenMax;
    import com.greensock.plugins.TransformAroundCenterPlugin;
    import com.greensock.plugins.TweenPlugin;  
    import flash.display.Sprite;
    import flash.events.Event;
    import flash.events.ProgressEvent; 
    import mx.events.FlexEvent;
    import mx.preloaders.SparkDownloadProgressBar;
    public class TJProgressBar extends SparkDownloadProgressBar
        private var PreloaderSymbol:Class = TJPreloader; ///from libs/TJProgressBar.swc
        private var _preloaderSymbol:TJPreloader;
        private var _preloader:Sprite;
        public function TJProgressBar()
            super();
               TweenPlugin.activate([TransformAroundCenterPlugin])
            _preloaderSymbol = new PreloaderSymbol(); //in libs TJProgressBar.swc
            _preloaderSymbol.does_he.visible = false;              
             addChild(_preloaderSymbol); 
             centerPreloader()
             TweenMax.from(_preloaderSymbol,4,{rotationY:12, onComplete:preloaderComplete})
        private function centerPreloader():void{
             trace('centering: '+stageWidth+" "+stageHeight)
              _preloaderSymbol.x = stageWidth/2;
             _preloaderSymbol.y = stageHeight/2; 
        override public function set preloader(preloader:Sprite):void{
            _preloader = preloader;
            _preloader.addEventListener(ProgressEvent.PROGRESS, onDownloadProgress);
            _preloader.addEventListener(FlexEvent.INIT_COMPLETE, onFlexInitComplete);
        private function onDownloadProgress(event:ProgressEvent):void{
            var percent:Number = (100 * (event.bytesLoaded / event.bytesTotal)) >> 0;
            _preloaderSymbol.updatePreloader(percent);
        private function onFlexInitComplete(event:FlexEvent):void{
             _preloaderSymbol.does_he.visible = true
             TweenMax.killTweensOf(_preloaderSymbol)
             TweenMax.to(_preloaderSymbol,.5,{transformAroundCenter:{rotationY:0}, onComplete:preloaderDelay})
        private function preloaderDelay():void{
            TweenMax.delayedCall(.5,preloaderComplete);
          private function preloaderComplete():void{
            TweenMax.killTweensOf(_preloaderSymbol)
            removeChild(_preloaderSymbol);
            killEventListeners();
            killObjects();
            dispatchEvent(new Event(Event.COMPLETE));
        private function killEventListeners():void{
            _preloader.removeEventListener(ProgressEvent.PROGRESS, onDownloadProgress);
            _preloader.removeEventListener(FlexEvent.INIT_COMPLETE, onFlexInitComplete);
        private function killObjects():void{
             _preloader = null;
            _preloaderSymbol = null;
            PreloaderSymbol = null;
        // Override to return true so progress bar appears
        // during initialization.      
        override protected function showDisplayForInit(elapsedTime:int,
            count:int):Boolean {
                return true;
        // Override to return true so progress bar appears during download.    
        override protected function showDisplayForDownloading(
            elapsedTime:int, event:ProgressEvent):Boolean {
                return true;

Answer 1

i figured it out! it turns out the stageWidth and stageHeight is not set until the preloader is set. so i moved the centerPreloader() from the constructor to the preloader setter:
        override public function set preloader(preloader:Sprite):void{
              _preloader = preloader;
             centerPreloader();
                _preloader.addEventListener(ProgressEvent.PROGRESS, onDownloadProgress);
            _preloader.addEventListener(FlexEvent.INIT_COMPLETE, onFlexInitComplete);
worked perfect! Thanks for the help. -b