ABAP OO与ALV结合方式探索(1)

用OO来开发,尤其是在复杂业务的开发过程中

从程序设计的角度而言,应该更简单一点

而ALV是二次开发中登场很高的一个控件

最近做了一些尝试,探索OO的代码和ALV的结合使用

 

使用控件型的ALV

ALV直接写在BO对象中

本质上,只是用OO的语法来重写了一下form的调用方式

初步实现了OO和ALV的使用

 

TYPES:

  BEGIN OF ts_bo,

    datum TYPE sy-datum,

    uzeit TYPE sy-uzeit,

    value TYPE string,

  END OF ts_bo,

  tt_bo TYPE ts_bo OCCURS 0.

CLASS lcl_bo DEFINITION.

  PUBLIC SECTION.

    METHODS:

      mock,"模拟业务操作

      alv_config," alv 显示参数

      alv_display."alv

  PRIVATE SECTION.

    DATA:

      gt_bo       TYPE        tt_bo,

      gt_fieldcat TYPE        lvc_t_fcat," 显示字段列表

      gs_layout   TYPE        lvc_s_layo , " 页面布局

      g_container TYPE REF TO cl_gui_custom_container, " 容器

      g_grid      TYPE REF TO cl_gui_alv_grid. "  显示Grid

ENDCLASS.

CLASS lcl_bo IMPLEMENTATION.

  METHOD mock.

    DATA: ls_bo TYPE ts_bo.

    DO 10 TIMES.

      ls_bo-datum = sy-datum + sy-index.

      ls_bo-uzeit = sy-uzeit.

      ls_bo-value = 'Times:' && sy-index.

      APPEND ls_bo TO gt_bo.CLEAR ls_bo.

    ENDDO.

  ENDMETHOD.

  METHOD alv_config.

    DATA:

      ls_fieldcat TYPE lvc_s_fcat.

    ls_fieldcat-fieldname = 'DATUM'.ls_fieldcat-coltext = '日期'. APPEND ls_fieldcat TO gt_fieldcat.CLEAR ls_fieldcat.

    ls_fieldcat-fieldname = 'UZEIT'.ls_fieldcat-coltext = '时间'. APPEND ls_fieldcat TO gt_fieldcat.CLEAR ls_fieldcat.

    ls_fieldcat-fieldname = 'VALUE'.ls_fieldcat-coltext = '内容'. APPEND ls_fieldcat TO gt_fieldcat.CLEAR ls_fieldcat.

    gs_layout-sel_mode = 'A'.

    gs_layout-zebra = 'X' .

    gs_layout-cwidth_opt = 'X'.

  ENDMETHOD.

  METHOD alv_display.

    IF g_grid IS INITIAL.

      CREATE OBJECT g_container

        EXPORTING

          container_name = 'C0100'.

      CREATE OBJECT g_grid

        EXPORTING

          i_parent = g_container.

      CALL METHOD g_grid->set_table_for_first_display

        EXPORTING

*         I_BUFFER_ACTIVE               =

*         I_CONSISTENCY_CHECK           =

*         I_STRUCTURE_NAME              =

*         is_variant                    = gs_variant

          i_save                        = 'A'

          i_default                     = 'X'

*         is_layout                     = gs_layout

*         IS_PRINT                      =

*         IT_SPECIAL_GROUPS             =

*         it_toolbar_excluding          = gt_exclude

*         IT_HYPERLINK                  =

        CHANGING

          it_outtab                     = gt_bo

          it_fieldcatalog               = gt_fieldcat

*         it_sort                       = gt_sort

*         IT_FILTER                     =

        EXCEPTIONS

          invalid_parameter_combination = 1

          program_error                 = 2

          too_many_lines                = 3

          OTHERS                        = 4.

    ELSE.

      CALL METHOD g_grid->refresh_table_display.

    ENDIF.

  ENDMETHOD.                    "display

ENDCLASS.

DATA:

  ok_code TYPE        sy-ucomm,

  go_bo   TYPE REF TO lcl_bo.

START-OF-SELECTION.

  CREATE OBJECT go_bo.

  go_bo->mock( ).

  go_bo->alv_config( ).

  CALL SCREEN 100.

MODULE status_0100 OUTPUT.

  SET PF-STATUS 'PS100'.

  go_bo->alv_display( ).

ENDMODULE.                 " STATUS_0100  OUTPUT

MODULE user_command_0100 INPUT.

  CASE ok_code.

    WHEN 'BACK'.

      SET SCREEN 0.

  ENDCASE.

ENDMODULE.                 " USER_COMMAND_0100  INPUT

 

效果如下:

从代码上也能体现

method仅仅是替代了form的作用

并没有体现出OO的什么特性

如果一个程序中有多个ALV  多个复杂的对象

唯一的好处就是每个对象的数据独立了出来

比一股脑的全局数据要好一点

 

一个BO对象既要关注取数逻辑

又要关注显示功能

从设计模式中类的角度而言

无法满足单一职责的要求

显然这种代码的组织方式还可以改进

 

未完待续…

下一篇 数据与显示的分离