DOCUMENT:Q136848  15-FEB-2000  [foxpro]
TITLE   :PRB: Class Browser: "Unable to Display Class Hierarchy" Error
PRODUCT :Microsoft FoxPro
PROD/VER:WINDOWS:3.0
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

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

When a Class library is browsed in the Class Browser and a class that has
subclasses is removed, the error "Unable to Display Class Hierarchy" is
displayed when the Class Browser form is refreshed.

CAUSE
=====

A class contains an explicit reference to its parent in a .vcx file. If the
parent class is removed, the derived class cannot find its parent, and the class
hierarchy is incorrect.

RESOLUTION
==========

Remove the child classes first, and then delete the parent class.

STATUS
======

This behavior is by design.

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

Steps to Reproduce Behavior
---------------------------

1. Start the Class Browser (On the Tools menu, click Class Browser).

2. Open a class that has some child classes. For example, open the Tsbase.vcx
   file located in the Vfp\Mainsamp\Libs directory.

3. Click the Remove button to delete a class that has derived classes. For
   example, delete TSBASEFORM. The error "Unable to Display class hierarchy" is
   displayed.

Additional query words: VFoxWin

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

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