Tip 211: Changing or Removing the Desktop Wallpaper in Visual Basic 4.0

February 28, 1996

Abstract

Using the Microsoft® Windows® application programming interface (API) SystemParametersInfo function, you can remove or change the default desktop wallpaper from within your Microsoft Visual Basic® 4.0 application.

Using SystemParametersInfo to Remove/Select Wallpaper

In a Microsoft® Visual Basic® application, the Microsoft Windows® application programming interface (API) SystemParametersInfo function can be used to set many different system-wide parameters. One of these parameters is the desktop wallpaper. Normally, a user would select a new desktop wallpaper by using Control Panel.

As shown in the example program below, the SystemParametersInfo function can be called with the SPI_SETDESKWALLPAPER value and the name of the wallpaper you want to select. The Windows 95 operating system will then make this the new default wallpaper.

The SPIF_SENDWININICHANGE value tells Windows 95 that it should notify all top-level windows of the new change to the system-wide parameters.

Example Program

This program shows how to remove and select a new desktop wallpaper from within a Visual Basic application.

1. Create a new project in Visual Basic. Form1 is created by default.
   
   
2. Add the following Constant and Declare statements to the General Declarations section of Form1 (note that the Declare statement must be typed as a single line of code):

   Private Declare Function SystemParametersInfo Lib "user32" Alias 
      "SystemParametersInfoA" (ByVal uAction As Long, ByVal uParam As Long, 
      ByVal lpvParam As String, ByVal fuWinIni As Long) As Long
   Const SPIF_UPDATEINIFILE = &H1
   Const SPI_SETDESKWALLPAPER = 20
   Const SPIF_SENDWININICHANGE = &H2
   

3. Add a Command Button control to Form1. Command1 is created by default. Set its Caption property to "Remove Wallpaper".
   
   
4. Add the following code to the Click event for Command1 (note that the "X =" statement must be typed as a single line of code):

   Private Sub Command1_Click()
       Dim X As Long
       X = SystemParametersInfo(SPI_SETDESKWALLPAPER, 0&, "(None)", 
          SPIF_UPDATEINIFILE Or SPIF_SENDWININICHANGE)
       MsgBox "Wallpaper was removed"
   End Sub
   

5. Add a second Command Button control to Form1. Command2 is created by default. Set its Caption property to "Change Wallpaper".
   
   
6. Add the following code to the Click event for Command2 (note that the "X =" statement must be typed as a single line of code):

   Private Sub Command2_Click()
       Dim FileName As String
       Dim X As Long
   
       FileName = "c:\windows\pinstripe.bmp"
   
       X = SystemParametersInfo(SPI_SETDESKWALLPAPER, 0&, FileName, 
          SPIF_UPDATEINIFILE Or SPIF_SENDWININICHANGE)
       MsgBox "Wallpaper was changed"
   End Sub
   

Run the example program by pressing F5. To remove the wallpaper, click the "Remove Wallpaper" command button. Windows 95 displays a black background with no graphics whatsoever. Click the "Change Wallpaper" command button to change the wallpaper to the PINSTRIPE.BMP image.

Additional References

"Desktop Window." (MSDN Library, Platform, SDK, and DDK Documentation)

Knowledge Base Q97142. "How to Use SystemParametersInfo API for Control Panel Settings."

"SystemParametersInfo QuickInfo Overview Group." (MSDN Library, Platform, SDK, and DDK Documentation)

"Tip 5: Removing the Desktop Wallpaper."