actionscript 3 - As3 AddChild() in a Class -

im in as3 , im trying add movieclip inside of class don't errors image not show up.

this class code, movieclip called woopa1

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] code in frame calling class

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

why doesn't image show up?

have added enemy instance display list?

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

also since create instance of woopa1 class , add koopa, koopa class should extend movieclip or sprite instead of woopa1 class.

on separate note, may want name classes names start uppercase character. koopa should koopa , woopa1 should woopa1.