Q142194: FIX: Control Class in Control Not Shown in Control Array

Article: Q142194
Product(s): Microsoft FoxPro
Version(s): WINDOWS:3.0,3.0b
Operating System(s): 
Keyword(s): kbvfp kbvfp300bBUG kbvfp500fixkbbuglist kbfixlist
Last Modified: 24-MAR-2000

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, versions 3.0, 3.0b 
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SYMPTOMS
========

When one control class is added to another control class, the AMEMBERS()
function and the Controls array do not see the control class that was added.
This occurs whether the classes are created programmatically or visually.

STATUS
======

Microsoft has confirmed this to be a problem in the Microsoft products listed at
the beginning of this article. This problem has been fixed in Visual FoxPro 5.0
for Windows.

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

The following code creates two control classes: Ctl and Subcontrol. The program
adds the Subcontrol class to the Ctl class. The ADD OBJECT method also adds two
command buttons and a two-page pageframe to the Ctl class. Therefore, Ctl class
contains the Subcontrol class, two command buttons, and a pageframe.

The object positions referenced in the class definitions only apply if the class
is created visually.

The code example uses the AMEMBERS() function to place properties, procedures,
and member objects into a memory variable array named atest. Because the
Printmembers function is part of the Ctl class, it should have access to all the
objects within that class. However, the AMEMBERS() functions lists all the
objects in class except the subclass object. The AMEMBERS() function should have
to access to all the members of its own class.

Steps to Reproduce Problem
--------------------------

1. Create a program called Test.prg, and add the following code:

     ** Ctl Class Definition
     DEFINE CLASS ctl AS control

        ADD OBJECT command1 AS commandbutton WITH ;
           Top = 31
           Left = 23

        ADD OBJECT command2 AS commandbutton WITH ;
           Top = 81
           Left = 21

        ADD OBJECT pageframe1 AS pageframe WITH ;
           ErasePage = .T.
           PageCount = 2
           Top = 115
           Left = 37

        ADD OBJECT subcontrol1 AS subcontrol WITH ;
           Top = 6
           Left = 146

        PROCEDURE printmembers

           ACTIVATE SCREEN
           x=This.name
           ? AMEMBERS(atest,This,2)
           DISPLAY MEMORY LIKE atest

           FOR ii = 1 TO This.ControlCount
             ? This.controls[ii].Name
           ENDFOR

           ? This.SubControl1.Name
        ENDPROC

     ENDDEFINE

     *-- EndDefine: ctl

     ** Subcontrol Class Definition

     DEFINE CLASS subcontrol AS control
     ENDDEFINE

2. In the Command window, type each of the following commands on a separate
  line:

     SET LIBRARY TO TEST.PRG
     X=CREATEOBJECT('Ctl')
     X.Printmembers

The array atest contains elements representing the command buttons and the
pageframe objects that appear listed on the desktop. However, the Subcontrol
class object is not listed. The AMEMBERS() functions does not find the
Subcontrol object because it was added as a control. This causes the error
message "Property Controls is not found." If the "Ignore" button is pressed, an
"Unknown member SUBCONTOL1" message is displayed.

Additional query words:

======================================================================
Keywords          : kbvfp kbvfp300bBUG kbvfp500fix kbbuglist kbfixlist
Technology        : kbVFPsearch kbAudDeveloper kbVFP300 kbVFP300b
Version           : WINDOWS:3.0,3.0b
Issue type        : kbbug
Solution Type     : kbfix

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