This.variable (simple question)

Hi everyone,

I just started learning AS3, and I’m having a good time with it so far, but I stumbled upon something I have no idea how to fix. If I were more experienced, I probably could find a solution easily, but alas, I barely know any AS3. I can’t go on learning without figuring out exactly what’s wrong with this, since it’s going to bug me in the back of my mind until I do. That’s the way I work.

Here is the code:

package{
    import flash.display.*;
    import flash.text.*;
    import flash.events.*;
    
    public class sandBox extends MovieClip{
        
        public function sandBox(){
            var myText:TextField = new TextField();
            myText.text = "SUP."
            addChild(myText);
            for(var i:int=0;i<10;i++){
                var Circle:Sphere = new Sphere();
                Circle.x = 40*i+50;
                Circle.y = 200;
                Circle.scaleX = i*.4;
                Circle.scaleY = i*.4;
                Circle.buttonMode = true;
                Circle.addEventListener(MouseEvent.CLICK,clickCircle);
                function clickCircle(event:MouseEvent){
                    this.y += 10;
                }
                addChild(Circle);
            }
        }
        
    }
}

Specifically, my problem regards this:

                function clickCircle(event:MouseEvent){
                    this.y += 10;
                }

When I click any of the Circles, nothing happens. My intention is to make clicking a Circle move it down.

Thank you for your time.