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Q136848: PRB: Class Browser: "Unable to Display Class Hierarchy" Error

Article: Q136848
Product(s): Microsoft FoxPro
Version(s): WINDOWS:3.0
Operating System(s): 
Keyword(s): 
Last Modified: 15-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
========

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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