DOCUMENT:Q251321  11-JAN-2001  [vbwin]
TITLE   :BUG: ScrollBar Controls Exhibit Paint Problems In Change Event
PRODUCT :Microsoft Visual Basic for Windows
PROD/VER:WINDOWS:4.0,5.0,6.0
OPER/SYS:
KEYWORDS:kbCtrl kbScrollBar kbVBp kbVBp400bug kbVBp500bug kbVBp600bug kbGrpDSVB kbDSupport

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The information in this article applies to:

 - Microsoft Visual Basic Standard Edition, 32-bit, for Windows, versions 5.0, 6.0 
 - Microsoft Visual Basic Professional Edition, 32-bit, for Windows, versions 5.0, 6.0 
 - Microsoft Visual Basic Enterprise Edition, 32-bit, for Windows, versions 5.0, 6.0 
 - Microsoft Visual Basic Standard Edition, 32-bit, for Windows, version 4.0 
 - Microsoft Visual Basic Professional Edition, 16-bit, for Windows, version 4.0 
 - Microsoft Visual Basic Professional Edition, 32-bit, for Windows, version 4.0 
 - Microsoft Visual Basic Enterprise Edition, 16-bit, for Windows, version 4.0 
 - Microsoft Visual Basic Enterprise Edition, 32-bit, for Windows, version 4.0 
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SYMPTOMS
========

In Microsoft Visual Basic, the intrinsic HScrollBar and VScrollBar controls
experience painting problems if the mouse is moved off the control prior to the
completion of code execution in the Change event.

RESOLUTION
==========

To work around this behavior, the scrollbar control can be disabled at the start
of the Change event. Once the code execution is complete, the control can then
be enabled again.

   Private Sub HScroll1_Change()
      HScroll1.Enabled = False

      ' place your code here 

      HScroll1.Enabled = True
   End Sub

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article.

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

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

1. Start a new Visual Basic Standard EXE project. Form1 is created by default.

2. Add an HScrollBar control to Form1.

3. Add the following code to the General Declarations section of Form1:

   Private Sub HScroll1_Change()
       t = Timer
       While Timer < (t + 2)  ' to give you time to move the mouse
           DoEvents
       Wend
   End Sub

4. Press the F5 key to run the program.

5. Click on the RIGHT ARROW of the HScrollBar control. Note that the RIGHT ARROW
   appears in a depressed state.

6. Before the RIGHT ARROW of the HScrollBar returns to the raised state, move
   the mouse off the HScrollBar control and position the mouse over any portion
   of the client area of Form1.

7. When the RIGHT ARROW of the HScrollBar returns to the raised state, click
   once on the HScrollBar thumb. Note that the thumb receives focus and begins
   flashing.

8. Drag the HScrollBar thumb to the the right side of the control. Note that
   both the RIGHT and LEFT ARROWs of the HScrollBar control are now selected and
   in a depressed state.

Additional query words:

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Keywords          : kbCtrl kbScrollBar kbVBp kbVBp400bug kbVBp500bug kbVBp600bug kbGrpDSVB kbDSupport 
Technology        : kbVBSearch kbAudDeveloper kbVB400Search kbVB400 kbVB16bitSearch
Version           : WINDOWS:4.0,5.0,6.0
Issue type        : kbbug
Solution Type     : kbnofix

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