Tile pattern

I want to tile a pattern acros the stage, but I want to load it with loader (png file).

I used to do it like that, **Tile **being bitmap in the library with export name Tile


var pattern:Sprite = new Sprite();
addChild(pattern);
var g:Graphics = pattern.graphics;
function resizeHandler(event:Event=null):void
{
    var sw:Number = stage.stageWidth;
    var sh:Number = stage.stageHeight;

    g.clear();
    g.beginBitmapFill(new **Tile**(0, 0));
    g.drawRect(0, 0, sw, sh);
    g.endFill();
}

but now i need to load that png first:

function completeHandler(event:Event):void {
       var image:Bitmap = Bitmap(loader.content);
       _bitmapData=new BitmapData(image.width, image.height);
       _bitmapData.draw(image);
}

what do i need to do actually to send this to beginBitmapFill ?