Le 02/10/2014 09:22, Ulrike Fischer a écrit :

> Beside this there is also the timing problem Joseph mentioned: when
> should be tested if a key has been used? It is obviously not the key
> code of the key that can do it. So imho you are not looking for a
> .required property but a .enableifsettest property which adds and
> sets some boolean which you can later check.

Or better yet, use an initial value for your property that unambiguously 
represents "not set", and validate that at the beginning.

Since you need to have an extra step to check if the required properties 
have been set, you can as well use a token list to store the value 
instead of directly an int for instance, and first check if it is your 
special "not set" value, then cast it to integer yourself.

Julien "_FrnchFrgg_" Rivaud