As3 AddChild() in a Class

Im in as3 and Im trying to add a MovieClip inside of a Class I don't get any errors but my image does not show up.

This is my Class Code, my MovieClip is called woopa开发者_如何学JAVA1

package
{
    import flash.display.MovieClip;
    import woopa1;

    public class koopa extends woopa1
    {
        public function koopa()      
        {
            trace(woopa1);
            var woopa:woopa1 = new woopa1();
            addChild(woopa);
            woopa.x=100;
            woopa.y=100;
            woopa.height = 60;
            woopa.width = 38;
        }
    }
}

It traces [Class woopa1] this is my Code in the frame calling the class

function onenterEnemy(event:Event):void
{
   var enemy:koopa = new koopa();
}

Why doesn't my image show up?

Have you added your enemy instance to the display list?

var enemy:koopa = new koopa(); 
addChild(enemy);

Also since you create an instance of your woopa1 class and add it to koopa, your koopa class should probably extend MovieClip or Sprite instead of your woopa1 class.

On a separate note, you may also want to name your classes with names that start with an uppercase character. So koopa should be Koopa and woopa1 should be Woopa1.