DOCUMENT:Q185626  18-MAY-1998  [vbwin]
TITLE   :BUG: PictureBox Cannot be Made Transparent Using SetWindowLong
PRODUCT :Microsoft Visual Basic for Windows
PROD/VER:WINDOWS:5.0
OPER/SYS:WINDOWS
KEYWORDS:

======================================================================
---------------------------------------------------------------------
The information in this article applies to:

 - Microsoft Visual Basic Control Creation, Learning, Professional, and
   Enterprise Editions for Windows, version 5.0
---------------------------------------------------------------------

SYMPTOMS
========

Attempting to use the Windows SetWindowLong API function to set the window
style of a Visual Basic Picturebox to transparent does not work. However,
this method was successful with earlier versions of Visual Basic.

RESOLUTION
==========

There is not a solution that allows the API to work in this manner on the
intrinsic Visual Basic 5.0 PictureBox control. To workaround this problem,
you can replace the PictureBox control with a custom or third party control
that offers the same basic functionality as the PictureBox control but does
not exhibit the same SetWindowLong limitation.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed
at the beginning of this article. We are researching this bug and will post
new information here in the Microsoft Knowledge Base as it becomes
available.

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

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

1. Create a new Standard EXE project. Form1 is created by default.

2. Add two PictureBox controls, named Picture1 and Picture2, to Form1.

3. Set the BackColor property of Picture1 to red.

4. Position Picture2 so that it partially overlaps the Picture1 control.

5. Place the following code in the code module of Form1:

      Option Explicit
      Const GWL_EXSTYLE = (-20)
      Const WS_EX_TRANSPARENT = &H20&

      Private Declare Function SetWindowLong Lib "user32" Alias _
          "SetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long, _
          ByVal dwNewLong As Long) As Long

      Private Sub Form_Load()
          Dim result As Long
          Picture2.ZOrder
          result = SetWindowLong(Picture2.hwnd, GWL_EXSTYLE, _
             WS_EX_TRANSPARENT)
      End Sub

6. Run the sample project.

   RESULT: The Picture2 control is not made transparent so Picture1 is not
   completely revealed. In earlier versions of Visual Basic this code
   allowed Picture1 to be completely revealed.

Additional query words: kbSDKWin32 kbAPI
======================================================================
Version           : WINDOWS:5.0
Platform          : WINDOWS
Issue type        : kbbug
Solution Type     : kbnofix

=============================================================================

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Copyright Microsoft Corporation 1998.