Hi
Whenever you want a user to get involve it is a dialog step.
For me you should use something like this in your transaction
IF iv_action = 'A'.
IV_DECISION = '0001'. "Approval Node
ELSEIF iv_action = 'R'.
IV_DECISION = '0002' ."Rejection Node
ENDIF.
call function 'SAP_WAPI_DECISION_COMPLETE'
exporting
workitem_id = ME->WIID
LANGUAGE = SY-LANGU
USER = IV_USER
decision_key = IV_DECISION
DO_COMMIT = 'X'
DECISION_NOTE = IO_NOTE
IMPORTING
* RETURN_CODE =
NEW_STATUS = RV_STATUS
* TABLES
* MESSAGE_LINES =
* MESSAGE_STRUCT =
.
This is just an example, but it means you don't need to use event as the decision complete will send the decision taken and complete the workitem.
For the approval of several workitem at the same time I am against this all time, if a user has to approve something he first need to check one by one what he is approving otherwise why do you need a workflow to ask him what he thinks...
Cheers
Stephane