Drop down list for User ID's and SAP List viewer format

Question

Couple of quick questions. Any help will be greatly appreciated.
1) I need to put User ID on the selection criteria screen. And also, I need to build a dropdown list for user ID selection by finding all user IDs in the Finance department and put it on the list.
2) I need to display the report in the SAP List viewer format, which enable these functions including sorting, hiding fields, filtering, exporting to an excel file as necessary. My output is currently plain vanilla as follows
loop at ibkpf where belnr = ibseg-belnr.
       read table iskat with key saknr = ibseg-hkont.
       read table icepct with key prctr = ibseg-prctr.
       read table icskt with key kostl = ibseg-kostl.
       write:/
       iBKPF-BELNR,     " Accounting document number
       iBKPF-BUKRS,    " Company code
       iBKPF-GJAHR,     " Fiscal Year Range
       iBKPF-MONAT,     " Period
       iBKPF-USNAM,     " Username
       iBSEG-BELNR,      "Document #
       iBSEG-BUZEI,      "Item #
       iBSEG-BSCHL,      "Posting Key
       iBSEG-SHKZG,      "Debit/credit indicator
       iBSEG-PRCTR,      "Profit Center
       icepct-ktext,
       iBSEG-KOSTL,      "Cost Center
       icskt-ltext,
       iBSEG-HKONT,      "G/L Account
       iskat-TXT20,
       iBSEG-DMBTR,      "Local currency
       iBSEG-WRBTR,      "Document currency
       iBSEG-SGTXT,      "Explanation
       iBSEG-KOART.      "Account type

Answer 1

Hello Syed
Here is a sample coding for a dropdown listbox:
*& Report  ZUS_SDN_DROPDOWN_LIST
REPORT  zus_sdn_dropdown_list.
TYPE-POOLS: vrm. " Value Request Manager: Typen und Konstanten
DATA:
  gt_values   TYPE vrm_values.
PARAMETERS:
  p_usrid    TYPE xubname AS LISTBOX VISIBLE LENGTH 13.
INITIALIZATION.
* Select the allowed values for dropdown listbox
  SELECT bname AS key FROM  usr02 INTO TABLE gt_values
         WHERE  bname  LIKE 'S%'.
  CALL FUNCTION 'VRM_SET_VALUES'
    EXPORTING
      id              = 'P_USRID'
      values          = gt_values
    EXCEPTIONS
      id_illegal_name = 1
      OTHERS          = 2.
  IF sy-subrc <> 0.
* MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
*         WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
  ENDIF.
START-OF-SELECTION.
END-OF-SELECTION.
You have two fields for the listbox available:
- KEY (obligatory)
- TEXT (optional)
Regards
  Uwe