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Article: Q171821
Product(s): Microsoft Visual Basic for Windows
Version(s): 5.0
Operating System(s): 
Keyword(s): kbVBp500 kbVS97sp2fix kbGrpDSVB kbvbp500sp2fix
Last Modified: 11-JAN-2001

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The information in this article applies to:

- Microsoft Visual Basic Learning Edition for Windows, version 5.0 
- Microsoft Visual Basic Professional Edition for Windows, version 5.0 
- Microsoft Visual Basic Enterprise Edition for Windows, version 5.0 
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SYMPTOMS
========

When repeatedly changing the Width of one or more Toolbar Buttons at run- time,
you may experience a degradation in performance and/or a resource leak that is
not replenished until your application ends.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. This bug has been fixed in Visual Studio 97 Service
Pack 2.

For more information on the Visual Studio 97 Service Pack 2, please see the
following article in the Microsoft Knowledge Base:

  Q170365 INFO: Visual Studio 97 Service Packs - What, Where, and Why

For a list of the Visual Basic 5.0 bugs that were fixed in the Visual Studio 97
Service Pack 2, please see the following article in the Microsoft Knowledge
Base:

  Q171554 INFO: Visual Basic 5.0 Fixes in Visual Studio 97 Service Pack 2

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

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

1. Open a new "Standard EXE" project.

2. Click Components on the Project menu. Check "Microsoft Windows Common
  Controls 5.0".

3. Add an ImageList control, a ToolBar control and a CommandButton to Form1.

4. In the Custom property page for ImageList1, click the Images tab and insert
  one picture. Click OK.

5. In the Custom property page for Toolbar1, set the Imagelist property to
  "ImageList1." Insert one button and set the Image property to 1. Insert
  another button and set the style to 4-tbrPlaceholder. Click OK.

6. Add the following code to the Click event of Command1.

        For i = 1 To 100
             Toolbar1.Buttons(2).Width = 500
             Debug.Print i
             DoEvents
           Next

7. Click Immediate Window on the View menu.

8. Press the F5 key to run the application.

9. Click Command1. Notice that performance degrades after each iteration of
  changing the width of the Button Placeholder.

Additional query words: memory leak comctl32.ocx tool bar

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Keywords          : kbVBp500 kbVS97sp2fix kbGrpDSVB kbvbp500sp2fix 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVBA500 kbVB500
Version           : 5.0
Issue type        : kbbug
Solution Type     : kbfix

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Q171821: FIX: Memory Leak When Repeatedly Changing Toolbar Button Width