OO方式实现ALV： cl_salv_table

这里总结最近用cl_salv_table实现ALV遇到问题和解决办法

FORM set_alv2 .
DATA: lv_syrepid TYPE syrepid.
      lv_syrepid  = sy-cprog.
      cl_salv_table=>factory(
        EXPORTING
        list_display = abap_false
        r_container = cl_gui_container=>screen0
        IMPORTING
          r_salv_table = gr_alv
        CHANGING t_table = gt_doc ). “传输需要显示的内表

      gr_functions = gr_alv->get_functions( ).        "获取常用的ALV功能按钮

DATA lv_icon TYPE string.
lv_icon = icon_refresh.
gr_functions->add_function(       "添加自定义按钮
 EXPORTING
   name = 'DOWNLOAD'
   icon = '@M9@'
   text = '下载文档'
   tooltip = '下载文档'
   position = if_salv_c_function_position=>right_of_salv_functions ). "往右边排

gr_functions->add_function(
 EXPORTING
   name = 'SELECT_ALL'
   icon = '@4B@'
   text = '全选'
   tooltip = '全选'
   position = if_salv_c_function_position=>left_of_salv_functions ). "往右边排

gr_functions->add_function(
 EXPORTING
   name = 'DESELECT_ALL'
   icon = '@4D@'
   text = '取消全选'
   tooltip = '取消全选'
   position = if_salv_c_function_position=>left_of_salv_functions ). "往右边排

gr_functions->set_all( abap_true ). ”设置所有alv按钮（自带的+自定义的）
"=====获取事件对象
DATA: gr_event TYPE REF TO cl_salv_events_table.
gr_event = gr_alv->get_event( ).

"=====事件注册
DATA: gr_handle_event TYPE REF TO cl_handle_events.
CREATE OBJECT gr_handle_event.
SET HANDLER gr_handle_event->on_user_command FOR gr_event.
SET HANDLER gr_handle_event->on_checkbox     FOR gr_event.
DATA: gr_column_list TYPE REF TO cl_salv_column_list.

      gr_columns = gr_alv->get_columns( ).               "获取列的class
      gr_column  = gr_columns->get_column('ACTION_NO').  "获取该列
      gr_column->set_short_text('需求号').　　　　　　　　"调用修改列名称的方法
      gr_columns->set_optimize( abap_true ).　　　　　 "调用设置列最优化设置方法这边用到列实例是gr_colums不是gr_colum

      gr_column = gr_columns->get_column('FLAG').  

      gr_column->set_short_text('选择').
      gr_columnt ?= gr_column.                      "这边很重要
      gr_columnt->set_cell_type(  ).　　　　　　　　　　"设置选择列为checkbox，6代表checkbox

      gr_display = gr_alv->get_display_settings( ).  "alv设置
      gr_display->set_list_header('需求号&文档编号报表'). "alv抬头设置
      gr_alv->display( )."调用实例方法显示表报　　　　　　　　"调用显示alv方法展示ALV报表
ENDFORM.                    " SET_ALV2

下面是是事件的class的定义
CLASS cl_handle_events DEFINITION.
  PUBLIC SECTION.
    METHODS: on_user_command FOR EVENT added_function OF cl_salv_events_table
                  IMPORTING e_salv_function,
             on_checkbox     FOR EVENT link_click OF cl_salv_events_table
                  IMPORTING row   column.

ENDCLASS.

CLASS cl_handle_events IMPLEMENTATION.
  METHOD on_user_command.
    PERFORM handle_user_command USING e_salv_function.
  ENDMETHOD.
  METHOD on_checkbox.
    PERFORM handle_clickbox USING row column.
  ENDMETHOD.
ENDCLASS.

事件的方法定义
FORM handle_user_command  USING p_function TYPE salv_de_function.

    CASE p_function.
    WHEN 'DOWNLOAD'.
       PERFORM down_doc.
    WHEN 'DESELECT_ALL'.
         gs_doc-flag = ' '.
         MODIFY gt_doc FROM gs_doc TRANSPORTING flag  WHERE flag = 'X'.
    WHEN 'SELECT_ALL'.
         gs_doc-flag = 'X'.
         MODIFY  gt_doc FROM gs_doc TRANSPORTING flag WHERE flag = ' '.

  ENDCASE.
     gr_alv->refresh( ).
ENDFORM.