User Exit/BTE for F-26 for sequencing clearing open items

Question

Hi All,
Is there a BTE/User exit to identify the items selected for clearing in F-26? ( On line item double click)
Based on the open items displayed we need to enforce a check that they are selected in a proper sequence.
Thanks in advance,
Puneet

Answer 1

Thanks for the reply.
I succeded creating the validation with an user-exit. I made the following steps:
1) I created the validation in GGB0 (for document header), issuing a standard message (420 "Exchange rate not found") from message class (ZRSAU) - which is a copy of RSAU message class (in the beggining I put no pre-requisites, checks or rules, just the message).
2) In OB28 I attached the validation (with call point document header) and I made it active (without batch input).
3) I copied the RGGBR000 program (which is standard program with an example of validation) into ZRGGBR00 (it should be maximum 8 characters).
Then I changed the ZRGGBR00 program (form U100) comparing the translation date (from BKPF) with the date from table TCURR (and exchange rate type M, and documents currency other than local currency).
If the program doesn't find any exchange rate in TCURR in that date, it issues the error message (assigned in GGB0).
4) In GGB0, I put the U100 user exit as a check and rule
5)  In GCX2, I attached the ZRGGBR00 program to the GBLR application area (which is for user exits for validations / rules).
Now it's working fine!