Q194908: BUG: Control Repaint Problems When ClipControls Set to False

Article: Q194908
Product(s): Microsoft Visual Basic for Windows
Version(s): 5.0,6.0
Operating System(s): 
Keyword(s): kbCtrl kbVBp kbVBp500bug kbVBp600bug kbOSWin95 kbOSWin98 kbGrpDSVB kbOSWinME
Last Modified: 28-JAN-2001

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The information in this article applies to:

- Microsoft Visual Basic Learning Edition for Windows, versions 6.0, 5.0 
- Microsoft Visual Basic Professional Edition for Windows, versions 6.0, 5.0 
- Microsoft Visual Basic Enterprise Edition for Windows, versions 6.0, 5.0 
- Microsoft Visual Basic Control Creation Edition for Windows, version 5.0 
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SYMPTOMS
========

Clicking on an application's icon on the operating system's taskbar causes some
controls to disappear.

CAUSE
=====

This problem occurs when a modal form is displayed while a second form in this
application is visible in the background and the background form consists of all
of the following:

1. Its "ClipControls" property is set to "False."

2. The controls not displaying correctly are child controls of another control
  rather than placed directly on the form (such as option buttons within a
  Frame control).

This problem will occur with any type of control as long as the conditions above
are met.

RESOLUTION
==========

There are two potential workarounds for this issue:

- Avoid setting ClipControls to False when a second modal form will be
  displayed.

- Leave the ClipControls property set to False but only display non-modal
  forms.

STATUS
======

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

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

The following example uses a Frame with OptionButtons to demonstrate this
behavior.

Steps To Reproduce
------------------

1. Create a Standard EXE project in Visual Basic. Form1 is created by default.

2. Add a Frame Control to Form1.

3. Place an OptionButton within the Frame.

4. Place an OptionButton directly on the form.

5. Set the form's "ClipControls" property to "False."

6. Add a CommandButton to Form1.

7. Paste the following code into Form1's code window:

         Private Sub Command1_Click()
            Form2.Show vbModal
         End Sub

8. From the Project menu, add a second form, Form2, to the Project.

9. Run the Project.

10. Click the CommandButton.

11. Position the forms such that they are both visible.

12. Click the Win95/Win98/WinMe/NT4/Win2000 Taskbar item labeled "Form1." Note
  that the OptionButton within the Frame control disappears. The OptionButton
  and CommandButton located directly on Form1 continue to display correctly.

Additional query words: paint

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Keywords          : kbCtrl kbVBp kbVBp500bug kbVBp600bug kbOSWin95 kbOSWin98 kbGrpDSVB kbOSWinME 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVB600Search kbVBA500Search kbVBA500 kbVBA600 kbVB500 kbVB600 kbZNotKeyword3
Version           : :5.0,6.0
Issue type        : kbbug
Solution Type     : kbpending

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