Nested Button Problem

programming flash
1

Hi all

I have created an invisible button myButton_btn inside a moviclip with instance name supermarket_mc. The supermarket_mc is based on a class Supermarket, which has the following code and works fine.

[COLOR=red]public class Supermarket extends MovieClip
{
public function Supermarket()
{ this.addEventListener(MouseEvent.MOUSE_DOWN,go); }

private function go(event:MouseEvent):void
{ this.play();
this.addEventListener(MouseEvent.MOUSE_UP,hop);
}
private function hop(event:MouseEvent):void
{ this.stop(); } }[/COLOR]

Now, if I have a button on Stage they work fine when I add a listener to them. However, when I add a listener to myButton_btn ie:
[COLOR=red]supermarket_mc.**myButton_btn **.addEventListener(MouseEvent.CLICK, turn); [/COLOR]
**[COLOR=#ff0000][COLOR=black]myButton_btn[/COLOR] [COLOR=black]does not react to click events[/COLOR] [/COLOR]**and I get an additional error
[COLOR=red]Error #1009: Cannot access a property or method of a null object reference.[/COLOR]
[COLOR=#ff0000][/COLOR]
[COLOR=black]I suspect that the MouseEvent.CLICK in the class definition overrides the MouseEvent.CLICK on the nested button. [/COLOR]
[COLOR=black][/COLOR]
[COLOR=black]Any help would be appreciated [/COLOR]

Thanks
Hagop