BAdi:BOM_UPDATE - Check update for BOM Save

需求：BOM中替代项目组要求同一组比率之和必须是100.

实现：BAdi:BOM_UPDATE

METHOD if_ex_bom_update~change_at_save.
  DATA:
        ls_wa   TYPE stpob,
        ls_str  TYPE string.

  TYPES:BEGIN OF ty_check,
    alpgr TYPE stpob-alpgr ,
    ewahr TYPE stpob-ewahr ,
    END OF ty_check.
  DATA:
        lt_check TYPE STANDARD TABLE OF ty_check,
        ls_check TYPE ty_check.

  LOOP AT delta_stpob INTO ls_wa WHERE selkz = 'X'.
    MOVE-CORRESPONDING ls_wa TO ls_check .
    COLLECT ls_check INTO lt_check .
  ENDLOOP.

  LOOP AT lt_check INTO ls_check.
    IF ls_check-ewahr <> .
      CONCATENATE 'The total number of Usage prob. of Group ' ls_check-alpgr ' must equal to 100.' INTO ls_str SEPARATED BY space.
      MESSAGE ls_str TYPE 'E' .
    ENDIF.
  ENDLOOP.
ENDMETHOD.