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Q129402: PRB: ERROR "<formname> not an object" When Accessing Form

Article: Q129402
Product(s): Microsoft FoxPro
Version(s): WINDOWS:3.0
Operating System(s): 
Keyword(s): kberrmsg
Last Modified: 12-FEB-2000

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 3.0 
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SYMPTOMS
========

Accessing a form causes the error message "Unknown member <formname>" to
be displayed.

CAUSE
=====

If a form is modal, the program pauses when it's displayed. A common reaction is
for the user is to close the form to allow the program to continue execution.
However, if the code that subsequently runs refers to any properties of the
form, the error message is displayed because the form is out of scope (closed).

WORKAROUND
==========

The WindowType property controls whether the form is modeless (the default) or
modal. Setting the WindowType property for the form or formset in the DEFINE
CLASS code to 0 (zero - modeless), or not including the WindowType property
(causing a default of 0) resolves the problem.

STATUS
======

This behavior is by design.

MORE INFORMATION
================

Because they are modal, the program below pauses after the two forms appear.
When the forms are closed, the program will continue after the FrsMyset.show
command. However, because the forms are closed, the error "Unknown member
FRMMYFORM1" is displayed.

       PUBLIC FrsMyset, FrmMyform1
     FrsMyset = CREATEOBJECT("myformset")
     FrsMyset.show

     FrsMyset.FrmMyform1.addobject("MyButton","commandbutton")
     FrsMyset.FrmMyform1.MyButton.left=40
     FrsMyset.FrmMyform1.MyButton.visible=.t.

     DEFINE CLASS myformset AS formset
        windowtype = 1    && this is the offending statement
        ADD OBJECT FrmMyform1 AS form
        FrmMyform1.caption="Form 1"
        add object FrmMyform2 as form
        FrmMyform2.caption="Form 2"
        FrmMyform2.autocenter=.t.

        PROCEDURE show
           =MESSAGEBOX("Show Method")
        ENDPROC
     ENDDEFINE

The WindowType property controls whether the form is modeless (the default) or
modal. If the form is modal, the user must close the form before accessing any
other elements of your application's user interface (see below).

WindowType
setting    Description
-----------------------------------------------------------------

0           Modeless.
1           Modal. No other Form objects can become active and
           the menu is inactive. All Form objects in the FormSet
           are active.
2           Read. The FormSet behaves as if it were activated by
           the READ command. Execution stops on the Show method
           or DO FORM command. When the Form is deactivated,
           execution continues. (Included for backward compatibility.)
3           Read Modal. The FormSet behaves as if it were activated
           by a READ command's   MODAL clause. Program execution stops
           at the Show method or the DO FORM command. Any Form objects
           specified in the WindowList property are available, but other
           Form objects and the menu are not available. (Included for
           backward compatibility.)

Removal of the WindowType property (or setting it to 0) in the class definition
allow the windows to be modeless and thus allow program execution to continue
after the windows are displayed.

Additional query words: VFoxWin model errmsg window 3.00

======================================================================
Keywords          : kberrmsg 
Technology        : kbVFPsearch kbAudDeveloper kbVFP300
Version           : WINDOWS:3.0

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