In that previous article I talked about adding an image to the library and instantiating it as a BitmapData object.  Then I talked about creating a Bitmap object, but there’s a problem; in the AS3 reference, on the Bitmap page, there’s this nugget of information:

Note: The Bitmap class is not a subclass of the InteractiveObject class, so it cannot dispatch mouse events. However, you can use the addEventListener() method of the display object container that contains the Bitmap object.

This makes it impossible to turn a Bitmap into, say, a button.  However, there is hope!

Instead of making a Bitmap object, make a Sprite object.  Then fill the Sprite’s graphics member with the bitmap.  Specifically, use the beginBitmapFill(), drawRect() and endFill functions.  Here’s some basic code to get you started:

var t_IconClass:Class = getDefinitionByName("picture0.png") as Class;
var t_BitmapData:BitmapData = new t_IconClass(0, 0);
var t_Sprite:Sprite = new Sprite();
t_Sprite.x = 64;  // Position it wherever you want
t_Sprite.y = 128;
t_Sprite.graphics.beginBitmapFill(t_BitmapData);
t_Sprite.graphics.drawRect(0, 0, t_BitmapData.width, t_BitmapData.height);
t_Sprite.graphics.endFill();
t_Sprite.addEventListener(MouseEvent.MOUSE_DOWN, SpriteClickFunc);
addChild(t_Sprite);


Here’s something interesting I’ve discovered:

When you add an image to a Flash file in the library, it becomes an “embedded asset”. In AS3, you can use the getDefinitionByName() function to find the embedded asset class based on its filename (well, its linkage name, which is by default its filename). Then you can instantiate the class and get a BitmapData class; you can use this to construct a Bitmap class, then use addChild or addChildAt to display it. The really interesting thing is that the documentation says the BitmapData constructor takes a height and width…but this doesn’t seem to matter in the case of embedded assets. Pass the constructor anything you want, even 0,0, and it should still instantiate and display correctly.

EDIT: The followup post has more about this and a better way to pull it off.

Also, I’ve started on an interactive fiction game called “The Duel” for TIGSource’s Commonplace Book Competition (horror-themed for the Halloween season!).  Check it out and make suggestions!