How to set values in the listbox?

Question

I have defined a list box in my selection screen, as follows:

SELECTION-SCREEN BEGIN OF BLOCK B2 WITH FRAME TITLE ALTITLE1.
SELECTION-SCREEN BEGIN OF LINE.
SELECTION-SCREEN COMMENT (30) ALCONT4 FOR FIELD L1.
PARAMETERS: L1 AS LISTBOX VISIBLE LENGTH 20 MODIF ID AOD.
SELECTION-SCREEN END OF LINE.
SELECTION-SCREEN END OF BLOCK B2.

Now I need to propose possible values for that list box, how can I do it ?

Answer 1

During the PBO of your screen (for selection screens, the PBO code is defined inside the event block AT SELECTION-SCREEN OUTPUT), you must call the function module VRM_SET_VALUES, passing the name of the field and a list of values.

SELECTION-SCREEN BEGIN OF BLOCK b2 WITH FRAME TITLE altitle1.
SELECTION-SCREEN BEGIN OF LINE.
SELECTION-SCREEN COMMENT (30) alcont4 FOR FIELD l1.
PARAMETERS: l1 AS LISTBOX VISIBLE LENGTH 20 MODIF ID aod.
SELECTION-SCREEN END OF LINE.
SELECTION-SCREEN END OF BLOCK b2.

INITIALIZATION.
  alcont4 = 'Choose the country'(001).

AT SELECTION-SCREEN OUTPUT.
  DATA: lt_value TYPE vrm_values,
        ls_value TYPE vrm_value.
  ls_value-key = 'DE'.
  ls_value-text = 'Germany'.
  APPEND ls_value TO lt_value.
  ls_value-key = 'FR'.
  ls_value-text = 'France'.
  APPEND ls_value TO lt_value.
  CALL FUNCTION 'VRM_SET_VALUES'
    EXPORTING
      id              = 'L1'
      values          = lt_value
    EXCEPTIONS
      id_illegal_name = 1
      OTHERS          = 2.

Execution:

For information, you can achieve the same result from the database table of countries T005T, by transferring the entries to an intermediate internal table:

  DATA: lt_t005t TYPE TABLE OF t005t,
        ls_t005t TYPE t005t.
  SELECT * FROM t005t
      INTO TABLE lt_t005t
      WHERE spras = 'E' " English names of countries
        AND land1 IN ('FR','DE').
  LOOP AT lt_t005t INTO ls_t005t.
    ls_value-key = ls_t005t-land1.
    ls_value-text = ls_t005t-landx50.
    APPEND ls_value TO lt_value.
  ENDLOOP.

You may find more information in the SAP Library (the explanations are valid for all kind of screens, the examples are only for classic screens but they may be adapted easily to selection screens): http://help.sap.com/saphelp_470/helpdata/en/9f/dbabe435c111d1829f0000e829fbfe/frameset.htm