combo entry changed signal?

[Todd Dukes <tdukes ibmoto com>]

I have a combo box where I want the value to have to be in the selection

list. But my rules for whether the value is contained or not are not
simple
text matching. The combo box can contain list, and ranges using my own
syntax. For example a range from 0 to 10 would be [0:10]. Legal values
could
be any sub-range of this, a single digit, or a list of any combination
of these.
If a illegal value is entered I would like to alert the user when the
combo
looses focus. This was done previously by changing the background of the

combo entry field to red.

I can't see any way to be notified when the focus has left the combo and

the entry has been changed. Am I missing something? Is there any way to
approximate the behavior I want?

thanks
Todd

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   | Todd Dukes                      E-MAIL:  tdukes@ibmoto.com |
   | Motorola Somerset                  Phone:   (512) 424-8008 |
   | MS OE70                                                    |
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   | Austin, Texas 78730                                        |
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