ALV 自定义全选按钮，选择框自动打勾

REUSE_ALV_GRID_DISPLAY 的 i_callback_user_command 参数定义

form user_command using ucomm  like sy-ucomm   selfield type slis_selfield.
  selfield-refresh = 'X'.
  selfield-col_stable = 'X'.
  selfield-row_stable = 'X'.

  data: lo_guid type ref to cl_gui_alv_grid.

  case ucomm.
    when 'ZEXEC'.
*  取得当前alv的grid
      call function 'GET_GLOBALS_FROM_SLVC_FULLSCR'
        importing
          e_grid = lo_guid.
      call method lo_guid->check_changed_data.

      selfield-refresh = 'X'.
      perform frm_update.   "可以写更新代码

    when 'SELECT'."全选
*  取得当前alv的grid
      call function 'GET_GLOBALS_FROM_SLVC_FULLSCR'
        importing
          e_grid = lo_guid.
      call method lo_guid->check_changed_data.
      selfield-refresh = 'X'.
      loop at r3_data.    "BOX 用作复选框列
        r3_data-box = 'X'.
        modify r3_data.
      endloop.

    when 'UNSELECT'."全不选
*  取得当前alv的grid
      call function 'GET_GLOBALS_FROM_SLVC_FULLSCR'
        importing
          e_grid = lo_guid.
      call method lo_guid->check_changed_data.
      loop at r3_data.
        r3_data-box = ''.
        modify r3_data.
      endloop.
      selfield-refresh = 'X'.
    when others.
  endcase.

endform.                    "user_command