Widget event-handler scope

Widget event-handler scope

Hello,
I am creating a custom widget and would like to know what is considered by others as a good practice for the following situation:
My widget has buttons in it, and the buttons need to change the state of the widget according to it's 'options' that it is configured with.  However, if I use an internal function that I created within my widget's "factory" (I think that's the right term?) as an event handler, I cannot get a reference to the widget's 'options' from within that handler.  I've created a dummy example to help explain my situation...

In this page there are two div's which I turn into instances of my "box-and-button" widget.  This widget has a parameter/option of "newColour" which is supposed to be the colour that the box changes to when its button is clicked.  However, I cannot get a reference to the widget's options within the _handleButtonClick function. Am I binding the 'click' handler incorrectly?  Is there a way I can pass a reference to the widget within the 'click' handler function?  Or can I get a reference to the widget from the passed event object perhaps?

Thanks for any help with this