Show image at certain percentage

programming flash
1

Is there a way I can do it so at a certain percentage of the preloader a image shows up?

Like lets say from 0-49% the background is black
then once it hits 50% an image shows up as the background, and stays there until 100%

so basicly 0-49% = black background
and 50-100% = show an image as a background

Is that possible?

Also, here is my current code I would like to add that option to:

stop();

this.addEventListener(Event.ENTER_FRAME, loading);

function loading(e:Event):void {

    var total:Number = this.stage.loaderInfo.bytesTotal;
    var loaded:Number = this.stage.loaderInfo.bytesLoaded;

    bar_mc.scaleX = loaded/total;
    loader_txt.text = "Loading config - " + Math.floor((loaded/total)*100) + "%";

    if (total == loaded) {
        play();
        this.removeEventListener(Event.ENTER_FRAME, loading);
    }

}

Also, this is a preloader.