# Mouselisteners in classes

**URL:** <https://forum.kirupa.com/t/mouselisteners-in-classes/240743>\
**Category:** Uncategorized\
**Created:** [October 5, 2007, 4:45pm UTC](https://forum.kirupa.com/t/mouselisteners-in-classes/240743 "2007-10-05T16:45:52Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![ArmoredSandwich](https://avatars.discourse-cdn.com/v4/letter/a/3e96dc/32.png) [@ArmoredSandwich](https://forum.kirupa.com/u/ArmoredSandwich)\
**Post date:** [October 5, 2007, 4:45pm UTC](https://forum.kirupa.com/t/mouselisteners-in-classes/240743/1 "2007-10-05T16:45:52Z")

</div>

Im new at OOP, and just learning to program classes. However i am wondering whats wrong with this…

```auto

class MouseListener
    {
    private var thisMouse;
    private var lastMouse;
    private var theListener;
    
    public function MouseListener()
        {
        this.theListener = new Object();
        Mouse.addListener(this.theListener);
        }
    public function getMouse():String
        {
        this.theListener.onMouseDown = function ()
            {
            this.thisMouse = "down";
            this.lastMouse = "down";
            }            
        _root.onMouseUp = function ()
            {
            thisMouse = "up";
            this.lastMouse = "up";
            }
        _root.onMouseMove = function ()
            {
            this.thisMouse = "move";
            }
        trace (this.thisMouse);
        return thisMouse;
        }
        
    public function getLastMouse():String
        {
        return this.lastMouse;
        }
    }

```

Why would this trace undefined? Its probably just a newb mistake, but id like some help with finding it.

thx