Visual Event shows:
- Which elements have events attached to them
- The type of events attached to an element
- The code that will be run with the event is triggered
- The source file and line number for where the attached function was defined (Webkit browsers and Opera only)
(above text copied from Visual Event page.)
I use Yii 1.1.12 at the time of writing. Should work with earlier versions.
Drop this in your extension directory and then call the widget somewhere (in your layout, ...).