TOP-OF-PAGE [DURING LINE-SELECTION].
This statement defines an event block whose event is triggered by the
ABAP runtime environment
during the creation of a list. This occurs when a new page is started - that is, immediately before
the first line in a new page is to be output. All list outputs that take place in the event block are
placed below the standard page header of the list. You cannot output more lines than are available in
the page within the event block. The
NEW-PAGE statement is ignored within this event block.
The entire output written to the list in the event block belongs to the page header of the current list page. The top page header cannot be moved when you scroll vertically in a list displayed on the screen.
TOP-OF-PAGE event, the placeholders "&1" - "&9" are replaced
with the contents of system fields
in the standard heading and the column headings of the standard page header during creation of a basic list. You can assign values to these system fields in the program.
... DURING LINE-SELECTION
If you do not use an addition, an event block is triggered for event
during the creation of a basic list. If you use the addition
an event block is triggered for the corresponding events during the creation of details lists. You have to use system fields like
sy-lsind to distinguish between the individual details lists.