ALV, event DATA_CHANGED, avoid insert of duplicate key

Question

Hello,
I would like to implement edit functionality of an internal table with ALV based on class CL_GUI_ALV_GRID. Some fields of internal table are key fields and the combination of them should be unique. The user has a possibility to add a new record (all fields in new record are editable) or change values in an existing record (only non-key fields are editable). So far so good, it works.
I'm doing a validation of entered data in the event DATA_CHANGED. In this event I'm checking if the new record is a duplicate combination of existing key fields. If yes, then all fields of the new record are reported as error with ADD_PROTOCOL_ENTRY method. This removes all entries related to this row from MT_GOOD_CELLS table and this is ok for me.
My problem: after validation ALV inserts such empty row in my internal table and next time, when the user makes a correction, this record is an update and not a new record (there is no entry in MT_INSERTED_ROWS).
Question: Is there a possibility to avoid ALV inserting a new record when all its cells are bad?
Regards,
Annie

Answer 1

Hi,
As far as i have understood your problem,you can try the following to avoid the insertion of an empty row:
When you must be creating an empty row,just set a flag say flag_create = 'X'.
Then when you are performing the validation then if there is an error then check for this flag that is :
if flag_create = 'X'.
then delete from the internal table based on sy-tabix.
endif.
This way the new row that got appended with wrong values will get deleted and the code will not consider this as an updated row.
Kindly <<deleted> if useful.:)
Follow the rules of engagement
Edited by: Vijay Babu Dudla on Jan 9, 2012 7:07 AM