How to create an "exit widget" button on iAd producer.

I am creating a widget for a children's book and would like to create a simple "exit button" (an X the reader can touch to close the widget). Thus far I have created the object, but i can't seem to find an an 'action' to associate with the "activated" event that will close the widget and return to the iBook. I realise that a widget can alternatively be closed with a two-finger gesture, but for simplicity in view of my target audience prefer to have the "exit button". Note: I am relatively new to iBooks Author, and totally new to iAd producer. Unfortunately I don't know how to script in Java or HTML yet, but am willing to learn. Can anyone please give me some pointers?