How do I monitor which widget was last selected?

[Stevie Griffiths <stevie craig griffiths gmail com>]

I've been trying to monitor a group of widgets (2 combo boxes, 1
togglebutton) and know when a widget not in this group is clicked / tabbed
into.

I was trying to use the "focus-out-event" to determine when to check.
However combo-boxes don't focus.  And I've been trying with grabs, to no
avail.

I feel I must be missing some concept or vocabulory as I am having trouble
asking google what to do in searchable terms. (also 5 times the pain using
a phone to do it xD)

Stevie.