when i debug my code nothing appears on screen. I've rechecked the code and consulted with others yet nothing appears. my html template is fine.

Question

package { import flash.display.Sprite; import flash.events.*;

public class asgnv2 extends Sprite
{ 
    var lineY = 0;
    public function asgnv2()
    {
        stage.addEventListener(Event.ENTER_FRAME, update);
        graphics.lineStyle(1);
    }
    function update(e){
        graphics.clear();
        graphics.moveTo(0 ,lineY);
        graphics.lineTo(100, lineY);
        lineY+=0.5;

        }

    }
}