SELECTION-SCREEN 组成
0. INITIALIZATION：可以将界面的按钮在此定义。
1. AT SELECTION-SCREEN：进行用户数据合法性的检查，发现Fehler 给出Meldung, 直到正确
2. START-OF-SELECTION： 在此事件中队业务需求进行系统数据查询
3. END-OF-SELECTION：结果清单输出
4. TOP-OF-PAGE/END-OF-PAGE：设计清单头，页脚

SELECTION-SCREEN 页面中添加Button，Checkbox und Eingabefelde
* -----------------------------------------------
*  Button
* -----------------------------------------------
SELECTION-SCREEN: FUNKTION KEY 1, FUNKTION KEY 2.
* -----------------------------------------------
*  Eingabefelde
* -----------------------------------------------
DATA: LP_YEAR TYPE n LENGTH 4.

SELECTION-SCREEN BEGIN OF BLOCK selection WITH FRAM TITLE TEXT-001.
    * Eingabe
    PARAMETERS P_NAME LIKE P_TYPE DEFAULT ' C1'.
    * Checkbox
    SELECT-OPTIONS: P_YEAR FOR LP_YEAR DEFAULT 2000 OBLIGATORY.
    SELECT-OPTIONS: ...
SELECTION-SCREEN END OF BOLCK selection.
* -----------------------------------------------
*  Checkbox
* -----------------------------------------------
SELECTION-SCREEN BEGIN OF BLOCK flags WITH FRAM TITLE TEXT-002.
    PARAMETERS: P_DEL AS CHECKBOX DEFAULT ' '.
    PARAMETERS: ...
SELECTION-SCREEN END OF BOLCK flags.
* -----------------------------------------------
*  Main Programm
* -----------------------------------------------
TABLES: sscrfields.

INITIALIZATION.
   CLEAR gs_pushbutton.
   gs_pushbutton-text := ' ....'.
   gs_pushbutton-icon_id := icon_display_note.
   gs_pushbutton-quickinfo := ' show ....'.
   sscrfieds-functxt_01: gs_pushbutton.

* Button Drücken ist unabhängig vom Eingabefeld.
AT SELECTION-SCREEN.
    CASE sscrfieds-ucomm.
     WENN 'FC01'.
       d_butt = 'FC01'.
       sscrfields-ucomm = 'ONLI'.

START-OF-SELECTION.
    IF d_butt EQ 'FC01'.
       ........... * Was passiert, wenn man FC01drückt.
       EXIT.
    ENDIF.