Hello George,

Thank you so much for your help .

You are right when you say to get a working example and do some changes.
That is what i'm trying to get...a working example.

All the examples i get here do not compile and i dont know why.
The one i posted ( descriptor ) is from this forum and it was suposed to be working but it does not compile

If someone would explain me why this does not compile maybe i would be able to fix it and move to the next stage.

Regards
Rui