Tracking the opening of an Overlay element

I'm using a Yahoo User Interface Overlay on a page and wondered if there is any way to track interaction with it, if only to just know how many times it's be开发者_StackOverflowen opened.

The overlay is triggered by clicking on an image.

Is there something I could add to this event?

You could subscribe to the event called showEvent on your Overlay: http://developer.yahoo.com/yui/docs/YAHOO.widget.Module.html#event_showEvent (Overlay inherits Module).