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Flow of an Executable Program
The SUBMIT statement loads the called program
in a separate internal session and starts a series of processes in the
ABAP runtime environment that
trigger events and actions in the called program in the following order:
Program constructor event
LOAD-OF-PROGRAM
The start values defined using the
DEFAULT addition in the statements PARAMETERS
and SELECT-OPTIONS are passed
to the relevant data objects. The start values of all other data objects
are set before LOAD-OF-PROGRAM .
Reporting event
INITIALIZATION
The selection screen specified in
selscreen_options is called if it
contains at least one input field or button. If no explicit selection
screen is specified, the standard selection screen is called. Complete
selection screen processing is
performed. After the selection screen processing, the program flow is
either continued or ended, depending on the last user action on the
selection screen. Before the first event of the selection screen
processing, AT SELECTION-SCREEN OUTPUT
, the values specified in selscreen_options are passed.
Reporting event
START-OF-SELECTION
Different GET events, if the called program is
associated with a logical database .
Reporting event
END-OF-SELECTION
The basic list is called.
If the basic list is empty, the program is exited..
If the basic list is a spool list, it is sent to the SAP spool system
and the program is exited.
If EXPORTING LIST TO MEMORY is
specified in list_options , the basic list is stored in the
ABAP Memory and the program is exited.
Otherwise, the basic list is a screen list and is displayed on the
screen. User actions on a displayed screen list trigger list events. The
program is exited when the user exits the list display.
If no selection screen is displayed in step 4, because processing is
performed in the background or not at all, the program flow is complete.
If a selection screen displayed in step 4, the runtime environment calls
the called program again after the basic list has been exited. During
this new call, the runtime environment supplies the parameters, the
selection criteria, and the free selections of the selection screen
between the events INITIALIZATION and
AT SELECTION-SCREEN OUTPUT
with the previous input values (other settings, such as whether the
tabstrip page was active, are not passed). The program call is not
complete until the user exits the selection screen processing by
choosing Back , Exit , or Cancel .
The called program can be exited in any of these steps by using the
LEAVE PROGRAM statement and
during list processing by using LEAVE
LIST-PROCESSING .
Note
If the called program is associated with a logical database, the system
calls the relevant subroutines of the
database program for the steps listed above. For information, see
Logical Databases - Associations with
Executable Programs .
Documentation extract taken from SAP system, � Copyright SAP AG. All rights reserved