ABAP modify screen：修改屏幕，实现隐藏、禁止输入字段

Loop at screen会loop处理屏幕上的每一个组件，并对其做相应的处理。

SELECTION-SCREEN: BEGIN OF BLOCK B1 WITH FRAME.
PARAMETERS S_DATE TYPE DATUM DEFAULT SY-DATUM MODIF ID OO.
SELECTION-SCREEN: END OF BLOCK B1.

SELECTION-SCREEN: BEGIN OF BLOCK B2 WITH FRAME.
SELECT-OPTIONS: S_DATE2 FOR SY-DATUM MODIF ID PP.
SELECTION-SCREEN: END OF BLOCK B2.

SELECTION-SCREEN: BEGIN OF BLOCK B3 WITH FRAME.
PARAMETERS : R1 RADIOBUTTON GROUP D1 DEFAULT 'X' USER-COMMAND SINGLECLICK,

R2 RADIOBUTTON GROUP D1 .
SELECTION-SCREEN: END OF BLOCK B3.

选择r1 的时候只显示B1；r2时候只显示B2

AT SELECTION-SCREEN OUTPUT.
  IF R1 = 'X'.
    LOOP AT SCREEN.
      IF SCREEN-GROUP1 = 'PP'.
        SCREEN-ACTIVE = '0'.
      ENDIF.
      MODIFY SCREEN.
    ENDLOOP.
  ELSEIF R2 = 'X'.
    LOOP AT SCREEN.
      IF SCREEN-GROUP1 = 'OO'.
        SCREEN-ACTIVE = '0'.
      ENDIF.
      MODIFY SCREEN.
    ENDLOOP.
  ENDIF.

Modiy屏幕的时候，如果屏幕有必输字段则不能修改，只有把必输项输入值后才能修改屏幕，需要有所取舍；
注意：

PARAMETERS : R1 RADIOBUTTON GROUP D1 DEFAULT 'X' USER-COMMAND SINGLECLICK, 红色这一段话必须有，否则不能动态修改屏幕；选择一次单选框就会触发一次atselection-screen output，实现动态修改屏幕.

SCREEN结构解释：

在SAP屏幕中，一个字段就像.NET中的一个控件，这个字段对应一个SCREEN结构，就像控件的多个属性。

SE11可以查看SCREEN结构中的字段，只是没有备注。

名称长度说明

NAME 30 屏幕字段的名称

GROUP1 3 属于字段组1的字段

GROUP2 3 属于字段组2的字段

GROUP3 3 属于字段组3的字段

GROUP4 3 属于字段组4的字段

ACTIVE 1 可见并准备输入的字段

REQUIRED 1 字段输入是强制的，即该值为X是表示该字段必须输入

INPUT 1 字段准备输入

OUTPUT 1 字段仅用于显示

INTENSIFIED 1 高亮显示字段

INVISIBLE 1 禁用字段

LENGTH 1 减少字段输出长度

DISPLAY_3D 1 以三维框架显示字段

VALUE_HELP 1 显示有值帮助的字段

上述长度为1的字段，=1表示有效，=0则相反。

转自：https://blog.csdn.net/zhongguomao/article/details/52710924

可以参考以下

REPORT zlongtext_up_down NO STANDARD PAGE HEADING.

TABLES: crmc_text,stxh,qmel,qmsm,qmfe,qmma,qmur,stpo.

DATA: fldcat          TYPE slis_t_fieldcat_alv WITH HEADER LINE,
      slayt           TYPE slis_layout_alv,
      varnt           LIKE disvariant,
      repid           LIKE sy-repid,
      i_title         TYPE lvc_title,
      i_grid_settings TYPE lvc_s_glay.
DATA: slines TYPE string.

DATA: header LIKE thead .
DATA: it_lines TYPE STANDARD TABLE OF tline WITH HEADER LINE.
DATA: BEGIN OF istr ,
        tdobject LIKE stxh-tdobject,"文本: 应用程序对象
        tdid     LIKE stxh-tdid,"Text ID
        tdspras  LIKE stxh-tdspras,"语言代码
        tdname   LIKE stxh-tdname,"Name
        tdformat TYPE tdformat ,"标记列
        line     TYPE tdline ,"文本行
      END OF istr.

*ALV显示
DATA: BEGIN OF itab OCCURS 0.
        INCLUDE STRUCTURE istr.
DATA:END OF itab.
*文本下载
DATA:itab_d LIKE istr OCCURS  0 WITH HEADER LINE.
DATA: BEGIN OF it_head OCCURS 0,
        tdobject LIKE stxh-tdobject,"文本: 应用程序对象
        tdid     LIKE stxh-tdid,"Text ID
        tdspras  LIKE stxh-tdspras,"语言代码
        tdname   LIKE stxh-tdname,"Name
      END OF it_head.
DATA : catalog LIKE tcatalog OCCURS 0 WITH HEADER LINE.
DATA: filename TYPE string,
      lf_rc    TYPE c.

SELECTION-SCREEN BEGIN OF BLOCK b0   WITH FRAME TITLE t0.
PARAMETERS: pr1 RADIOBUTTON GROUP typ0 USER-COMMAND sele DEFAULT 'X' MODIF ID m0.
PARAMETERS: pr2 RADIOBUTTON GROUP typ0  MODIF ID m0.
SELECTION-SCREEN END OF BLOCK b0.

SELECTION-SCREEN BEGIN OF BLOCK b1 WITH FRAME TITLE t1.

SELECT-OPTIONS: s_object FOR crmc_text-r3object OBLIGATORY DEFAULT 'VBBK' MODIF ID m1 ,
                s_tdid   FOR crmc_text-r3id MODIF ID m1 ,
                s_tdname FOR stxh-tdname MODIF ID m1.
PARAMETERS incstr TYPE string MODIF ID m1.
SELECTION-SCREEN SKIP.
PARAMETERS: p_alv RADIOBUTTON GROUP typ USER-COMMAND sele DEFAULT 'X'  MODIF ID m1.
PARAMETERS: p_dc RADIOBUTTON GROUP typ  MODIF ID m1.
PARAMETERS: p_dn RADIOBUTTON GROUP typ  MODIF ID m1.
PARAMETERS: p_df RADIOBUTTON GROUP typ  MODIF ID m1.
SELECTION-SCREEN END OF BLOCK b1.

SELECTION-SCREEN BEGIN OF BLOCK b4 WITH FRAME TITLE t4.
PARAMETERS: p_upc RADIOBUTTON GROUP typ2 USER-COMMAND sele DEFAULT 'X' MODIF ID m2.
PARAMETERS: p_upa RADIOBUTTON GROUP typ2 MODIF ID m2.
PARAMETERS: p_file LIKE ibipparms-path OBLIGATORY DEFAULT 'C:longtext.txt' MODIF ID m3 ,
            p_kong AS CHECKBOX MODIF ID m3 .
SELECTION-SCREEN END OF BLOCK b4.


AT SELECTION-SCREEN OUTPUT.

  t0 = '功能选择'.

  %_pr1_%_app_%-text = '导出'.
  %_pr2_%_app_%-text = '导入'.

  t1 = '导出功能'.
  %_p_alv_%_app_%-text = 'ALV显示'.
  %_p_dc_%_app_%-text = '复制到剪贴板'.
  %_p_dn_%_app_%-text = '保存到本地文本文件'.
  %_p_df_%_app_%-text = '保存到服务器文件'.
  %_p_alv_%_app_%-text = 'ALV显示'.
  %_s_object_%_app_%-text = '文本对象'.
  %_s_tdid_%_app_%-text   = '标识'.
  %_s_tdname_%_app_%-text = 'KEY'.
  %_incstr_%_app_%-text = '长文本包含字符串'.

  t4 = '导入功能'.
  %_p_upc_%_app_%-text = '数据来自剪贴板(不要复制标题)'.
  %_p_upa_%_app_%-text = '数据来自文本文件'.
  %_p_file_%_app_%-text   = '文件名'.
  %_p_kong_%_app_%-text = '允许上载长文本为空'.

  CLEAR:fldcat,fldcat[].
  PERFORM catlg_set USING 'TDOBJECT' '应用程序对象'(101).
  PERFORM catlg_set USING 'TDID' 'TEXT ID'(102).
  PERFORM catlg_set USING 'TDSPRAS' '语言代码'(103).
  PERFORM catlg_set USING 'TDNAME' 'NAME'(104).
  PERFORM catlg_set USING 'TDFORMAT' '标记列'(105).
  PERFORM catlg_set USING 'LINE' '文本行'(106).

  LOOP AT SCREEN.
    IF pr1 = 'X'.
      IF screen-group1 = 'M2' OR  screen-group1 = 'M3' .
        screen-active = '0'.
      ELSE.
        screen-active = '1'.
      ENDIF.
    ENDIF.

    IF pr2 = 'X' AND p_upa <> 'X'.
      IF screen-group1 = 'M1' OR screen-group1 = 'M3' .
        screen-active = '0'.
      ELSE.
        screen-active = '1'.
      ENDIF.
    ENDIF.

    IF pr2 = 'X' AND p_upa = 'X'.
      IF screen-group1 = 'M1'  .
        screen-active = '0'.
      ELSE.
        screen-active = '1'.
      ENDIF.
    ENDIF.

    MODIFY SCREEN.
  ENDLOOP.

AT SELECTION-SCREEN ON VALUE-REQUEST FOR p_file .
  CALL FUNCTION 'F4_FILENAME'
    EXPORTING
      program_name  = syst-cprog
      dynpro_number = syst-dynnr
      field_name    = ' '
    IMPORTING
      file_name     = p_file.
  filename = p_file.



START-OF-SELECTION.