關於選擇螢幕function
REPORT報表的自定義工具欄按鈕。
SELECTION-SCREEN: FUNCTION KEY 是包含在選擇畫面（1000）的標準GUI的功能按鈕，最多隻能有5個，功能碼是FC1~FC5.也是系統預留好的。
然後，以上被定義的按鈕的圖示和文字描述都是可以設定的，在tables：sscrfields的functxt_01 ，functxt_02，functxt_03…
REPORT XXXX_report.
TABLES SSCRFIELDS.
DATA GS_KEY LIKE SMP_DYNTXT.
SELECTION-SCREEN FUNCTION KEY 1.
SELECTION-SCREEN FUNCTION KEY 2.
FORM FRM_SET_FUNCTION .
GS_KEY-ICON_ID = ICON_TOOLS.
GS_KEY-ICON_TEXT = ‘XXX’.
SSCRFIELDS-FUNCTXT_01 = GS_KEY .
ENDFORM.
下面有個例子：
REPORT demo_sel_screen_function_key.
TYPE-POOLS icon.
TABLES sscrfields.
DATA functxt TYPE smp_dyntxt.
PARAMETERS: p_carrid TYPE s_carr_id,
p_cityfr TYPE s_from_cit.
SELECTION-SCREEN: FUNCTION KEY 1,
FUNCTION KEY 2.
INITIALIZATION.
functxt-icon_id = icon_ws_plane.
functxt-quickinfo = ‘Preselected Carrier’.
functxt-icon_text = ‘LH’.
sscrfields-functxt_01 = functxt.
functxt-icon_text = ‘UA’.
sscrfields-functxt_02 = functxt.
AT SELECTION-SCREEN.
CASE sscrfields-ucomm.
WHEN ‘FC01’.
p_carrid = ‘LH’.
p_cityfr = ‘Frankfurt’.
WHEN ‘FC02’.
p_carrid = ‘UA’.
p_cityfr = ‘Chicago’.
WHEN OTHERS.
…
ENDCASE.
