How To Set Screen Elements Status.

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*
*  Company XXX Company Limited
*
*  ProgrameName:  ZZW_SCREEN_PROCESS
*
*  Author: Lilo.Zhu
*
*  Date: 08/28/2007
*
*  Description: Practice ABAP Screen Input / invisable / Active.
*
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REPORT  ZZW_SCREEN_PROCESS                      .

Selection-Screen Begin Of Block B1 With Frame Title Text-001.
  Parameters: P_str1(10),
              P_Str2(10),
              P_Str3(10).
Selection-Screen End Of Block B1.

At Selection-Screen Output.
  Loop at Screen.
    If Screen-Name = 'P_STR1'.
      Screen-Input  =  ''.  "Gray,Only Output
      EndIf.
    If Screen-Name  = 'P_STR2'.
      Screen-Invisible = '1'. "* Set Mask Code,Sometime use for Password
    Endif.
    If Screen-Name  = 'P_STR3'.
      Screen-Active = '0'.   " 0-Not Show, 1-Show
    EndIf.
    MODIFY SCREEN.
  EndLoop.