Error #2025: addChaild and removeChild

Question

hello all
I have the app but I got a problem
ArgumentError: Error # 2025: The supplied DisplayObject must be a child of the caller.
at flash.display :: DisplayObjectContainer / removeChild ()
at xxxxx_fla :: MainTimeline / hitPoint ()
my code
import flash.events.Event;
import flash.events.MouseEvent;
var pencilta:Shape = new Shape();
var activeColor:uint = 0x000000;
var aaa:a = new a();
aaa.x = 0;
aaa.y = 0;
addChild(aaa);
var bbb:c1 = new c1();
bbb.x = 308;
bbb.y = 108;
addChild(bbb);
var ccc:c2 =new c2();
ccc.x = 265;
ccc.y = 175;
addChild(ccc);
var ddd:c2 = new c2();
ddd.x = 235;
ddd.y = 260;
var eee:c2 =new c2();
eee.x = 200;
eee.y = 355;
bbb.addEventListener(MouseEvent.MOUSE_DOWN, hta1drag);
bbb.addEventListener(MouseEvent.MOUSE_UP, hta1drop);
bbb.addEventListener(Event.ENTER_FRAME, hitPoint);
function drawingta()
          addChild(pencilta);
          pencilta.graphics.lineStyle(10, activeColor);
function drawPencilta(e:MouseEvent):void
          pencilta.graphics.lineTo(bbb.x, bbb.y);
          e.updateAfterEvent();
function hta1drag(e:MouseEvent):void
          e.target.startDrag();
          pencilta.graphics.moveTo(bbb.x, bbb.y);
          stage.addEventListener(MouseEvent.MOUSE_MOVE, drawPencilta);
          drawingta();
function hta1drop(e:MouseEvent):void
          stopDrag();
          stage.removeEventListener(MouseEvent.MOUSE_MOVE, drawPencilta);
function hitPoint(e:Event)
          if(bbb.hitTestPoint(ccc.x,ccc.y, true))
                    removeChild(ccc);
                    addChild(ddd);
          else if (bbb.hitTestPoint(ddd.x,ddd.y,true))
                    removeChild(ddd);
                    addChild(eee);
          else
                    trace ('mbuh lah');
thank's

Answer 1

use:
import flash.events.Event;
import flash.events.MouseEvent;
var pencilta:Shape = new Shape();
var activeColor:uint = 0x000000;
var aaa:a = new a();
aaa.x = 0;
aaa.y = 0;
addChild(aaa);
var bbb:c1 = new c1();
bbb.x = 308;
bbb.y = 108;
addChild(bbb);
var ccc:c2 =new c2();
ccc.x = 265;
ccc.y = 175;
addChild(ccc);
var ddd:c2 = new c2();
ddd.x = 235;
ddd.y = 260;
var eee:c2 =new c2();
eee.x = 200;
eee.y = 355;
bbb.addEventListener(MouseEvent.MOUSE_DOWN, hta1drag);
bbb.addEventListener(MouseEvent.MOUSE_UP, hta1drop);
bbb.addEventListener(Event.ENTER_FRAME, hitPoint);
function drawingta()
          addChild(pencilta);
          pencilta.graphics.lineStyle(10, activeColor);
function drawPencilta(e:MouseEvent):void
          pencilta.graphics.lineTo(bbb.x, bbb.y);
          e.updateAfterEvent();
function hta1drag(e:MouseEvent):void
          e.target.startDrag();
          pencilta.graphics.moveTo(bbb.x, bbb.y);
          stage.addEventListener(MouseEvent.MOUSE_MOVE, drawPencilta);
          drawingta();
function hta1drop(e:MouseEvent):void
          stopDrag();
          stage.removeEventListener(MouseEvent.MOUSE_MOVE, drawPencilta);
function hitPoint(e:Event)
          if(bbb.hitTestPoint(ccc.x,ccc.y, true))
if(ccc.stage){
                    ccc.parent.removeChild(ccc);
// ccc=null; ??
                    addChild(ddd);
          else if (bbb.hitTestPoint(ddd.x,ddd.y,true))
if(ddd.stage){
                    ddd.parent.removeChild(ddd);
// ddd = null; ??
                    addChild(eee);
          else
                    trace ('mbuh lah');
thank's