MouseEvents not responding within a class

Question

Hi
I have some code that draws a line that follows the mouse and fades away over time,
until now it was in the main file of my program but i want to make a class out of it for later use in other programs
i edited the code into a singleton MouseHandler class with one function that registers the mouse up and down events;
with trace and 'hasEventListener' i found out that the events are registered but nothing happenes when i press my mouse buttons
here is the class
package 
     import adobe.utils.ProductManager;
     import flash.display.DisplayObject;
     import flash.display.DisplayObjectContainer;
     import flash.display.MovieClip;
     import flash.display.Sprite;
     import flash.events.Event;
     import flash.events.MouseEvent;
     import flash.geom.Point;
      * @author Gadi G
     public class MouseHandler extends Sprite
          private  var _stage:DisplayObjectContainer;
          private var _bDraw:Boolean = false;
          private var _arrLine:Array = new Array();;
          private var _angle;
          private var _p1:Point =  new Point();
          private var _p2:Point = new Point();
          private var cos:Number;
          private var sin:Number;
          private var lineDrawing:Line;
          private var angle;
          private var distance:uint;
          private static var instance:MouseHandler;
          public function MouseHandler()
          public static function getInstance():MouseHandler
               if (instance == null)
                    instance = new MouseHandler();
               return instance;
          public function startListening(prnt:DisplayObjectContainer)
               _stage = prnt;
               _stage.addEventListener(MouseEvent.MOUSE_DOWN, mouseDownHandler);
               _stage.addEventListener(MouseEvent.MOUSE_UP, mouseUpHandler);
          private function mouseDownHandler(e:MouseEvent):void
               trace('down');
               _bDraw = true;
               _p2.x = mouseX;
               _p2.y = mouseY;
               _stage.addEventListener(Event.ENTER_FRAME, enterFrameHandler);
               _stage.addEventListener(MouseEvent.MOUSE_MOVE, drawMouseLine);
          private function mouseUpHandler(e:MouseEvent):void
               trace('up');
               _bDraw = false;
               _stage.removeEventListener(MouseEvent.MOUSE_MOVE, drawMouseLine);
          private function enterFrameHandler(e:Event):void
               for each (var s:Line in _arrLine)
                    s.scaleX = s.scaleY *=  .79;
                    // the lowest possile value is one twip which is 0.05
                    if (s.width < .7)
                         _arrLine.splice(_arrLine.indexOf(s), 1);
                         removeChild(s);
                         s = null;
               if (! _bDraw && _arrLine.length == 0)
                    _stage.removeEventListener(Event.ENTER_FRAME, enterFrameHandler);
          private function drawMouseLine(e:MouseEvent):void
               _p1.x = mouseX;
               _p1.y = mouseY;
               _angle = Math.atan2(_p1.y - _p2.y,_p1.x - _p2.x);
               var rot:Number = (180 / Math.PI ) * _angle + 180;
               cos = Math.cos(_angle);
               sin = Math.sin(_angle);
               distance = Math.round(Point.distance(_p1,_p2)) + 1;
               while (--distance)
                    lineDrawing = new Line();
                    lineDrawing.x = _p2.x;
                    lineDrawing.y = _p2.y;
                    lineDrawing.rotation = rot;
                    _arrLine.push(addChild(lineDrawing));
                    lineDrawing = null;
                    _p2.x +=  cos;
                    _p2.y +=  sin;
               _p2.x = _p1.x;
               _p2.y = _p1.y;
in my main class i just use
MouseHandler.getInstance().startListening(this);
Thanks

Answer 1

1. If you want to use "this" as a parameter - you need to place objects on display list of "this" scope so that mouse interaction can occur. Otherwise - pass Stage instance.
2. How does instance of Line know how to draw base on mouse coordinates? From your code it doesn't seem it draws anything.
3. You don't add Line instance to display list.
4. Why do you set lineDrawing instance to null in the loop?