Can eventlistener call a setter function?

Hi once again
I have a set function…

// AS3
 public function set toolName(thisTool:String)
   _theTool = thisTool;

and an eventlistener

newTool.addEventListener(MouseEvent.CLICK, clickTool);

The ClickTool function

private  function clickTool(event)
   thisTool = event.currentTarget + "";
   switch (thisTool)
    case "[object trowel]":

The problem is that when I use the get function I find that _theTool is not updated.

 public function get toolName():String
            return _theTool;

Could anyone help me with this please?