Showing field dynamically based on dropdown value

[kwiznix90]

Goodmorning,

I am new to SAP and ABAP programming and I am trying to make field visible dynamically, but only when a dropdown menu has a certain value, but I cant get it to work.

So first i set the field inactive in the PBO:

LOOP AT SCREEN.
  CASE SCREEN-NAME.
     WHEN 'FIELD A'.
        SCREEN-INPUT = 0.
        MODIFY SCREEN.
     WHEN 'FIELD B'.
       SCREEN-ACTIVE = 0.
       MODIFY SCREEN.
    ENDCASE.
  ENDLOOP.

And then in the PAI i read the value of the dropdown and if its the correct value, set them to active again.

IF dropdown-field = 1.
    LOOP AT SCREEN.
      CASE SCREEN-NAME.
        WHEN 'FIELD A'.
          SCREEN-INPUT = 1.
          MODIFY SCREEN.
        WHEN 'FIELD B'.
          SCREEN-ACTIVE = 1.
          MODIFY SCREEN.
      ENDCASE.
    ENDLOOP.
  ENDIF.

I tried with a error message, and that shows perfectly, but the fields just won't show up, what am I doing wrong??

Thanks in advance!

[Sandra_Rossi]

Let's start with a reproducible example, you can see that FIELD_A is changed into an input field:

PARAMETERS p_number TYPE i.
PARAMETERS field_a TYPE i.
PARAMETERS field_b TYPE i.

AT SELECTION-SCREEN OUTPUT.
  LOOP AT SCREEN.
    CASE screen-name.
      WHEN 'FIELD_A'.
        screen-input = 0.
        MODIFY SCREEN.
      WHEN 'FIELD_B'.
        screen-active = 0.
        MODIFY SCREEN.
    ENDCASE.
  ENDLOOP.

AT SELECTION-SCREEN.
  IF p_number = 1.
    LOOP AT SCREEN.
      CASE screen-name.
        WHEN 'FIELD_A'.
          screen-input = 1.
          MODIFY SCREEN.
        WHEN 'FIELD_B'.
          screen-active = 1.
          MODIFY SCREEN.
      ENDCASE.
    ENDLOOP.
    MESSAGE 'error' TYPE 'E'.
  ENDIF.

[former_member793384]

Hi,

kwiznix

1. So first you need to add your code(which you have written in PBO) in AT SELECTION-SCREEN OUTPUT event. This will help you see FIELD_A read only and FIELD_B as active on selection screen.2. When you want to modify the screen dynamically you will write your code(written by you in PAI) into AT SELECTION-SCREEN event. Here you can dynamically show fields based on whatever your dropdown value is.Regards,Anurag