Knowledge Base

BUG: Control Repaint Problems When ClipControls Set to False

Article ID: 194908

Article Last Modified on 5/12/2003

Microsoft Visual Basic 6.0 Learning Edition
Microsoft Visual Basic 5.0 Learning Edition
Microsoft Visual Basic 6.0 Professional Edition
Microsoft Visual Basic 5.0 Professional Edition
Microsoft Visual Basic 6.0 Enterprise Edition
Microsoft Visual Basic 5.0 Enterprise Edition
Microsoft Visual Basic 5.0 Control Creation Edition

This article was previously published under Q194908

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:

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

Create a Standard EXE project in Visual Basic. Form1 is created by default.
Add a Frame Control to Form1.
Place an OptionButton within the Frame.
Place an OptionButton directly on the form.
Set the form's "ClipControls" property to "False."
Add a CommandButton to Form1.

Paste the following code into Form1's code window:

       Private Sub Command1_Click()
          Form2.Show vbModal
       End Sub

From the Project menu, add a second form, Form2, to the Project.
Run the Project.
Click the CommandButton.
Position the forms such that they are both visible.
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

Keywords: kbbug kbctrl kbpending KB194908