Still having problems with IActiveDesktop

[Wjousts]

Okay, I think I've almost cracked this one. I got some more help by looking at Carlos Perez's explorer tree control which also uses some interfaces from Shell32. This is what I now have: using System; using Microsoft; using Microsoft.Win32; using System.Runtime.InteropServices; namespace ShellTypeLib { // Component structure for IActiveDeskTop [StructLayout(LayoutKind.Sequential)] struct COMPONENT { uint dwSize; uint dwID; int iComponentType; bool fChecked; bool fDirty; bool fNoScroll; COMPPOS cpPos; char[] wszFriendlyName; char[] wszSource; } [StructLayout(LayoutKind.Sequential)] struct COMPPOS { uint dwSize; int iLeft; int iTop; uint dwWidth; uint dwHeight; int izIndex; bool fCanResize; bool fCanResizeX; bool fCanResizeY; int iPreferredLeftPercent; int iPreferredTopPercent; } [StructLayout(LayoutKind.Sequential)] struct COMPONENTSOPT { uint dwSize; bool fEnableComponents; bool fActiveDesktop; } [StructLayout(LayoutKind.Sequential)] struct WALLPAPEROPT { uint dwSize; uint dwStyle; } // Declare IActiveDesktop interface [Guid("F490EB00-1240-11D1-9888-006097DEACF9")] [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)] interface IActiveDesktop { [PreserveSig] uint ApplyChanges(uint dwFlags); [PreserveSig] uint GetWallpaper([MarshalAs(UnmanagedType.LPWStr)]out string pwszWallpaper, uint cchWallpaper, uint dwReserved); [PreserveSig] uint SetWallpaper([MarshalAs(UnmanagedType.LPWStr)] string pwszWallpaper, uint dwReserved); [PreserveSig] uint GetWallpaperOptions(ref WALLPAPEROPT pwpo,uint dwReserved); [PreserveSig] uint SetWallpaperOptions(ref WALLPAPEROPT pwpo, uint dwReserved); [PreserveSig] uint GetPattern([MarshalAs(UnmanagedType.LPWStr)] string pwszPattern, uint cchPattern, uint dwReserved); [PreserveSig] uint SetPattern([MarshalAs(UnmanagedType.LPWStr)] string pwszPattern, uint dwReserved); [PreserveSig] uint GetDesktopItemOptions(ref COMPONENTSOPT pco, uint dwReserved); [PreserveSig] uint SetDesktopItemOptions(ref COMPONENTSOPT pcomp, uint dwReserved); [PreserveSig] uint AddDesktopItem(ref COMPONENT pcomp, uint dwReserved); [PreserveSig] uint AddDesktopItemWithUI(IntPtr hwnd, ref COMPONENT pcomp, uint dwReserved); [PreserveSig] uint ModifyDesktopItem(ref COMPONENT pcomp, uint dwFlags); [PreserveSig] uint RemoveDesktopItem(ref COMPONENT pcomp, uint dwReserved); [P

[David Stone]

I have never, in any language, using any method, been able to successfully change the wallpaper. I tried to change the RegKey, I tried to use the Active Desktop interface, I tried everything. I've also never found any examples of this...I think it's impossible.:( Norm Almond: I seen some GUI's in my life but WTF is this mess ;-) Leppie: I made an app for my sister and she wouldnt use it till it was colorful enough:) Norm:good point leppie, from that statement I can only deduce that this GUI must be aimed at children:laugh: Leppie:My sister is 25:eek: -Norm on the MailMagic GUI

[Stephane Rodriguez]

Simulate pressing F5 while you are on the desktop (WM_KEYDOWN, VK_F5). This should do the trick.

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sometimes it helps to look at the IL generated code a MS guy on develop.com "answering" .NET issues

[Wjousts]

Actually this works: // Imported COM function [DllImport("User32.dll")] private static extern bool SystemParametersInfo(int uiAction,int uiParam, string pvParam,int fWinIni); // Changes desktop wallpaper // string containing filename and path public static void ChangeWP(string strFileName) { SystemParametersInfo(20,0,strFileName,1); } The reason I wanted to get IActiveDesktop working (apart from personal satisfaction) is that it also has methods for changing the wallpaper options (stretch, tile, center, etc).

[David Stone]

Ah. I see. I think I saw that someplace else. I was just trying to do it with ActiveDesktop too because I had ActiveDesktop on at the time. So it was a bit of an exaggeration for me to say that I had never been able to do it...:-D Norm Almond: I seen some GUI's in my life but WTF is this mess ;-) Leppie: I made an app for my sister and she wouldnt use it till it was colorful enough:) Norm:good point leppie, from that statement I can only deduce that this GUI must be aimed at children:laugh: Leppie:My sister is 25:eek: -Norm on the MailMagic GUI

[Nathan Tran]

Hi, I'm tackling the same IActiveDesktop problem and was wondering if you managed to work it out. I hope this gets through to your email. Nathan.