The OpenEdge Hive

Introduction

Author: Todd G. Nist, Protech Systems Inc.

The source code for the window as shown in the picture is attached: w-disablex.w.
When you want to disable the [X]-button in the title bar and also want to remove the 'Close'-option from the system menu, you only have to call this function from within the main block of the window:

{windows.i}
 
FUNCTION DisableWindowClose RETURNS LOGICAL
  ( /* parameter-definitions */ ) :
/*---------------------------------------
  Purpose:  
    Notes:  
-----------------------------------------*/
  DEFINE VARIABLE hSysMenu   AS  INTEGER NO-UNDO.
  DEFINE VARIABLE hParent    AS  INTEGER NO-UNDO.
  DEFINE VARIABLE hInstance  AS  INTEGER NO-UNDO.
  DEFINE VARIABLE iRetCode   AS  INTEGER NO-UNDO.
  DEFINE VARIABLE iCnt       AS  INTEGER NO-UNDO.
 
  RUN GetParent IN hpApi(INPUT {&window-name}:HWND,
                         OUTPUT hParent).
 
  /* Get handle to the window's system menu
     (Restore, Maximize, Move, close etc.) */
  RUN GetSystemMenu IN hpApi(INPUT  hParent, 
                             INPUT  0,
                             OUTPUT hSysMenu).
 
  IF hSysMenu NE 0 THEN
  DO:
    /* Get System menu's menu count */
    RUN GetMenuItemCount IN hpApi(INPUT hSysMenu,
                                  OUTPUT iCnt).
 
    IF iCnt NE 0 THEN
    DO:
      /* Menu count is based on 0 (0, 1, 2, 3...) */
 
      /* remove the "close option" */
      RUN RemoveMenu IN hpApi(INPUT hSysMenu, 
                              INPUT iCnt - 1, 
                              INPUT {&MF_BYPOSITION} + {&MF_REMOVE},
                              OUTPUT iRetCode).
 
      /* remove the seperator */
      RUN RemoveMenu IN hpApi(INPUT hSysMenu, 
                              INPUT iCnt - 2, 
                              INPUT {&MF_BYPOSITION} + {&MF_REMOVE},
                              OUTPUT iRetCode).
 
      /* Force caption bar's refresh which 
         will disable the window close ("X") button */
      RUN DrawMenuBar IN hpApi(INPUT  hParent,
                               OUTPUT iRetCode).
      {&window-name}:TITLE = "Try to close me!".
    END. /* if iCnt NE 0... */
  END. /* if hSysMenu NE 0... */  
 
  RETURN FALSE.   /* Function return value. */
 
END FUNCTION.

Notes

Because you now have restricted the user from closing the window you will have to close it yourself from within 4GL. This statement will do it:

  apply "window-close" to {&window-name}. 

There are many ways for doing things. To refresh the title bar, instead of running DrawMenuBar, you could also

 run FlashWindow in hpApi(hParent,0, output iRetCode).