Preloading loadMovie

Im loading images into flash with loadMovie(imageArray[ArrayPos], _root.ImageHolder)
imageArray is an array with the paths to the images.
Anyways. When you press the next button it adds one to ArrayPos and then…calls this function

function LoadNextImage() {
ImageHolderAlphaOut = new Tween(_root.ImageHolder, “_alpha”, mx.transitions.easing.None.easeOut, 100, 0, 1, true);
if (ArrayPos == 1) {
LastImageHeight = HeightArray[HeightArray.length-1];
} else {
LastImageHeight = HeightArray[ArrayPos-1];
if (ArrayPos == 1) {
LastImageWidth = WidthArray[WidthArray.length-1];
} else {
LastImageWidth = WidthArray[ArrayPos-1];
ImageHolderAlphaOut.onMotionFinished = function() {
NextImageHeightTween = new Tween(_root.PlaceHolder, “_height”, mx.transitions.easing.None.easeIn, LastImageHeight, HeightArray[ArrayPos], 1, true);
NextImageWidthTween = new Tween(_root.PlaceHolder, “_width”, mx.transitions.easing.None.easeIn, LastImageWidth, WidthArray[ArrayPos], 1, true);
NextImageWidthTween.onMotionFinished = function() {
loadMovie(imageArray[ArrayPos], _root.ImageHolder);

		_root.ImageHolder._x = _root.PlaceHolder._x-(_root.WidthArray[ArrayPos]/2);
		_root.ImageHolder._y = _root.PlaceHolder._y-(_root.HeightArray[ArrayPos]/2);
		ImageHolderAlphaIn = new Tween(_root.ImageHolder, "_alpha", mx.transitions.easing.None.easeIn, 0, 100, 1, true);
		ImageHolderAlphaIn.onMotionFinished = function() {
			_root.Next.enabled = true;
			_root.BackBtn.enabled = true;


The problem is, if the image hasn’t finished completely loading, the tween “ImageHolderAlphaIn” doesn’t work. Im guessing it “technically” is working, but you just cant see it because the image hasn’t loaded yet, so its fading in nothing essentially.

So I want to make a preloader for the image. But I have no clue how to go about it.

Im guessing it should be on the root. Right after i use the loadMovie() in the function, but how do i get it to do…

if(_root.ImageHolder.getBytesLoaded() != _root.ImageHolder.getBytesTotal()){
} else { execute as normally]

Any help is greatly appreciated