Flash AS3: How to Make scroll bar react to dynamic textfield movement?

Question

I've been looking for a tutorial and answer to this for a while but can't find what I'm looking for. I am loading html text into a dynamic textfield, and I have a scrollbar controlling the scroll using the code below. What I want to do is also add scroll up/down buttons and have the scroll bar move in relation to the text scroll. I was just going to use "tracklistingtext.scrollV -- " for the scroll buttons, but right now the scroll bar doesn't recognize the text movement. What do I need to do to get the scroll bar to listen to the text scroll position?

var listTextreq:URLRequest=new URLRequest("tracklist.txt");
var listTextLoader:URLLoader = new URLLoader();
var bounds:Rectangle=new Rectangle(scrollMC.x,scrollMC.y,0,300);
var scrolling:Boolean=false;

function fileLoaded(event:Event):void {
 tracklistingtext.htmlText=listTextLoader.data;
 tracklistingtext.multiline=true;
 tracklistingtext.wordWrap=true;
 scrollMC.addEventListener(MouseEvent.MOUSE_DOWN, startScroll);
 stage.addEventListener(MouseEvent.MOUSE_UP, stopScroll);
 addEventListener (Event.ENTER_FRAME, enterHandler);

}

listTextLoader.addEventListener(Event.COMPLETE, fileLoaded);
listTextLoader.load(listTextreq);

function startScroll(e:Event):void {
 scrolling=true;
 scrollMC.startDrag(false,bounds);
}

function stopScroll(e:Event):void {
 scrolling=false;
 scrollMC.stopDrag();
}

function enterHandler (e:Event):void {
 if (scrolling == true) {
  tracklistingtext.scrollV = Math.round(((scrollMC.y - bounds.y)/300)*tracklistingtext.maxScrollV);
 }
}

Any help is greatly appreciated.

Answer 1

Replace the scrollHandler calculations with yours.

//...

function fileLoaded(event:Event):void {
    tracklistingtext.htmlText=listTextLoader.data;
    tracklistingtext.multiline=true;
    tracklistingtext.wordWrap=true;
    scrollMC.addEventListener(MouseEvent.MOUSE_DOWN, startScroll);
    stage.addEventListener(MouseEvent.MOUSE_UP, stopScroll);
    addEventListener (Event.ENTER_FRAME, enterHandler);
    /* !!! */ tracklistingtext.addEventListener(Event.SCROLL, scrollHandler);
}

//...

function scrollHandler(event:Event):void {
    scrollMC.y = (tracklistingtext.scrollV / tracklistingtext.maxScrollV) * bounds.height + bounds.y;
}