How to load and access bitmaps?

Question

Hey there!
     After a few days of frustration and searching the web, I've finally come to understand how to make a sprite sheet and animate it.  I understand classes and how to import external actionscript files which contain them into my Flash project.  The problem is, I can't figure out how to properly name and load a bitmap file from the folder and pass it onto my functions as arguements.  >_<
How do I load and access an external bitmap in Actionscript 3.0?
I'm using a class I found online here:  http://www.bensilvis.com/?p=229
The problem comes around when I try to access pieces of my bitmap, as he attempts to do here:  http://www.bensilvis.com/?p=317
var currentSprite:SpriteSheet = new SpriteSheet(sheet, 20, 20);
This is the only line that is confusing me, becuase he uses a variable "sheet", which is a bitmap, and I'm not sure how to define/name my external bitmap image as such.
SpriteSheet(tileSheetBitmap:Bitmap, width:Number = 16, height:Number = 16)
tileSheetBitmap: the Bitmap of the sprite sheet we will use
width: the width of  tiles in the sheet
height: the height of tiles in the sheet
Thank you!  <3

Answer 1

Actually, nevermind.  I got rid of the "new" and it worked fine.  My bitmap was converted and displalys fine.    Thank you very much!
However, I keep getting one last error:
  "Call to a possibly undefined methond DrawTile through a reference with a static type SpriteSheet."
...I'm not sure what I'm doing wrong.  Here's the DrawTile part of the class:
public function drawTile(tileNumber:int):BitmapData
            tileRectangle.x = int((tileNumber % rowLength)) * tileWidth;
            tileRectangle.y = int((tileNumber / rowLength)) * tileHeight;
            canvasBitmapData.copyPixels(tileSheetBitmapData, tileRectangle, tilePoint);
            return canvasBitmapData.clone();
...and here's my trouble code:
  var sprites:Bitmap = Bitmap(my_loader.content);
                     var MySheet:SpriteSheet = new SpriteSheet(sprites, 32, 32);
                    sprites.bitmapData = MySheet.DrawTile(0);
                    addChild(sprites);