If you need something like variant and want to control it, the push button on the selection screen can be the right solution.
The a sample selection screen with an extra push button and simple logic:

Here the source code:
DATA:
gv_dummy_bukrs TYPE bukrs,
gv_dummy_saknr TYPE saknr.
SELECT-OPTIONS:
so_bukrs FOR gv_dummy_bukrs.
SELECTION-SCREEN BEGIN OF LINE.
SELECTION-SCREEN COMMENT 1(30) FOR FIELD so_saknr.
SELECT-OPTIONS:
so_saknr FOR gv_dummy_saknr.
SELECTION-SCREEN PUSHBUTTON 83(6) text-t01 USER-COMMAND saknr_upload. " set text-t01 as 'Upload'
SELECTION-SCREEN END OF LINE.
AT SELECTION-SCREEN.
IF sy-ucomm = 'SAKNR_UPLOAD'.
clear so_saknr[].
so_saknr-sign = 'I'. so_saknr-option = 'EQ'. so_saknr-low = '0011000000'. append so_saknr.
so_saknr-sign = 'I'. so_saknr-option = 'EQ'. so_saknr-low = '0012000000'. append so_saknr.
so_saknr-sign = 'I'. so_saknr-option = 'EQ'. so_saknr-low = '0013000000'. append so_saknr.
ENDIF.
START-OF-SELECTION.
SELECT saknr INTO gv_dummy_saknr
FROM ska1
WHERE
saknr IN so_saknr.
WRITE: / gv_dummy_saknr.
ENDSELECT.
See other related notes on my website: