C#•2y ago

❔ problem changing the opacity of desktop icons via windows api

I have a code thath i made using information on internet and it works but some times the desktop get blacks depending on the opacity of the icons

31 Replies

maria 🌟•2y ago

code in peaces

  private const int GWL_EXSTYLE = -20;
        const int WS_EX_LAYERED = 0x00080000;    // Creates a layered window. 
        const int WS_EX_TRANSPARENT = 0x00000020;    // Not painted until after siblings beneath the window 
        const int WS_EX_TOOLWINDOW = 0x00000080;    // Creates a floating toolbar window, does not appear in the taskba
        private const int LWA_ALPHA = 0x2;


        public static int CurrentAlpha = GetDesktopIconOpacity();
        public static void SetDesktopIconsOpacity(int Alpha)
        {
            IntPtr hWnd = GetDesktopHwnd();

            IntPtr exStyle = NativeMethods.GetWindowLong(hWnd, GWL_EXSTYLE);

            // 
            NativeMethods.SetWindowLong(hWnd, GWL_EXSTYLE, (IntPtr)(exStyle.ToInt64() | WS_EX_LAYERED | WS_EX_TOOLWINDOW));


            int CoreAlpha = (int)(255 * (double)Alpha / 100);

            if (Alpha != 100 & Alpha != 0)
            {
                CoreAlpha += 1;
            }

            NativeMethods.SetLayeredWindowAttributes(hWnd, 0, (byte)CoreAlpha, LWA_ALPHA);
            //NativeMethods.SendMessage(hWnd, (0x1000 + 38), IntPtr.Zero, (IntPtr)ColorTranslator.ToWin32(Color.Transparent));

            //NativeMethods.UpdateWindow(hWnd);

            CurrentAlpha = Alpha;
        }

  private const int GWL_EXSTYLE = -20;
        const int WS_EX_LAYERED = 0x00080000;    // Creates a layered window. 
        const int WS_EX_TRANSPARENT = 0x00000020;    // Not painted until after siblings beneath the window 
        const int WS_EX_TOOLWINDOW = 0x00000080;    // Creates a floating toolbar window, does not appear in the taskba
        private const int LWA_ALPHA = 0x2;


        public static int CurrentAlpha = GetDesktopIconOpacity();
        public static void SetDesktopIconsOpacity(int Alpha)
        {
            IntPtr hWnd = GetDesktopHwnd();

            IntPtr exStyle = NativeMethods.GetWindowLong(hWnd, GWL_EXSTYLE);

            // 
            NativeMethods.SetWindowLong(hWnd, GWL_EXSTYLE, (IntPtr)(exStyle.ToInt64() | WS_EX_LAYERED | WS_EX_TOOLWINDOW));


            int CoreAlpha = (int)(255 * (double)Alpha / 100);

            if (Alpha != 100 & Alpha != 0)
            {
                CoreAlpha += 1;
            }

            NativeMethods.SetLayeredWindowAttributes(hWnd, 0, (byte)CoreAlpha, LWA_ALPHA);
            //NativeMethods.SendMessage(hWnd, (0x1000 + 38), IntPtr.Zero, (IntPtr)ColorTranslator.ToWin32(Color.Transparent));

            //NativeMethods.UpdateWindow(hWnd);

            CurrentAlpha = Alpha;
        }

        public static int GetDesktopIconOpacity() => NativeMethods.GetLayeredWindowAttributes(GetDesktopHwnd(), out uint crKey, out byte bAlpha, out uint dwFlags) ? (100 * bAlpha) / 255 : 255;

        private static Process ExplorerProcess;
        private static IntPtr LastExplorerIconsHandle;
        private static IntPtr GetDesktopHwnd()
        {
            if (ExplorerProcess != null)
            {
                if (ExplorerProcess.HasExited)
                {
                    ExplorerProcess = null;

                    return GetDesktopHwnd();
                }
                else
                {
                    return LastExplorerIconsHandle;
                }
            }

            ExplorerProcess = Process.GetProcessesByName("explorer").FirstOrDefault();

            IntPtr hWnd = NativeMethods.FindWindow("Progman", "Program Manager");
            hWnd = NativeMethods.FindWindowEx(hWnd, IntPtr.Zero, "SHELLDLL_DefView", null);
            hWnd = NativeMethods.FindWindowEx(hWnd, IntPtr.Zero, "SysListView32", "FolderView");

            if (hWnd == IntPtr.Zero)
            {
                IntPtr hDesktop = NativeMethods.GetDesktopWindow();

                foreach (var handle in GetChildWindows(hDesktop))
                {
                    hWnd = NativeMethods.FindWindowEx(handle, IntPtr.Zero, "SHELLDLL_DefView", null);

                    if (hWnd == IntPtr.Zero)
                    {
                        continue;
                    }

                    hWnd = NativeMethods.FindWindowEx(hWnd, IntPtr.Zero, "SysListView32", "FolderView");

                    if (hWnd != IntPtr.Zero)
                    {
                        break;
                    }
                }
            }

            LastExplorerIconsHandle = hWnd;

            return hWnd;
        }

        public static int GetDesktopIconOpacity() => NativeMethods.GetLayeredWindowAttributes(GetDesktopHwnd(), out uint crKey, out byte bAlpha, out uint dwFlags) ? (100 * bAlpha) / 255 : 255;

        private static Process ExplorerProcess;
        private static IntPtr LastExplorerIconsHandle;
        private static IntPtr GetDesktopHwnd()
        {
            if (ExplorerProcess != null)
            {
                if (ExplorerProcess.HasExited)
                {
                    ExplorerProcess = null;

                    return GetDesktopHwnd();
                }
                else
                {
                    return LastExplorerIconsHandle;
                }
            }

            ExplorerProcess = Process.GetProcessesByName("explorer").FirstOrDefault();

            IntPtr hWnd = NativeMethods.FindWindow("Progman", "Program Manager");
            hWnd = NativeMethods.FindWindowEx(hWnd, IntPtr.Zero, "SHELLDLL_DefView", null);
            hWnd = NativeMethods.FindWindowEx(hWnd, IntPtr.Zero, "SysListView32", "FolderView");

            if (hWnd == IntPtr.Zero)
            {
                IntPtr hDesktop = NativeMethods.GetDesktopWindow();

                foreach (var handle in GetChildWindows(hDesktop))
                {
                    hWnd = NativeMethods.FindWindowEx(handle, IntPtr.Zero, "SHELLDLL_DefView", null);

                    if (hWnd == IntPtr.Zero)
                    {
                        continue;
                    }

                    hWnd = NativeMethods.FindWindowEx(hWnd, IntPtr.Zero, "SysListView32", "FolderView");

                    if (hWnd != IntPtr.Zero)
                    {
                        break;
                    }
                }
            }

            LastExplorerIconsHandle = hWnd;

            return hWnd;
        }

 [DllImport("user32.dll")]
        public static extern uint GetWindowThreadProcessId(IntPtr hWnd, out uint lpdwProcessId);

        [DllImport("user32.Dll")]
        [return: MarshalAs(UnmanagedType.Bool)]
        public static extern bool EnumChildWindows(IntPtr parentHandle, Win32Callback callback, IntPtr lParam);

        public delegate bool Win32Callback(IntPtr hwnd, IntPtr lParam);

        List<IntPtr> GetRootWindowsOfProcess(int pid)
        {
            List<IntPtr> rootWindows = GetChildWindows(IntPtr.Zero);
            List<IntPtr> dsProcRootWindows = new List<IntPtr>();
            foreach (IntPtr hWnd in rootWindows)
            {
                uint lpdwProcessId;
                GetWindowThreadProcessId(hWnd, out lpdwProcessId);
                if (lpdwProcessId == pid)
                    dsProcRootWindows.Add(hWnd);
            }
            return dsProcRootWindows;
        }

        public static List<IntPtr> GetChildWindows(IntPtr parent)
        {
            List<IntPtr> result = new List<IntPtr>();
            GCHandle listHandle = GCHandle.Alloc(result);
            try
            {
                Win32Callback childProc = new Win32Callback(EnumWindow);

                EnumChildWindows(parent, childProc, GCHandle.ToIntPtr(listHandle));
            }
            finally
            {
                if (listHandle.IsAllocated)
                    listHandle.Free();
            }
            return result;
        }

        private static bool EnumWindow(IntPtr handle, IntPtr pointer)
        {
            GCHandle gch = GCHandle.FromIntPtr(pointer);
            List<IntPtr> list = gch.Target as List<IntPtr>;
            if (list == null)
            {
                throw new InvalidCastException("GCHandle Target could not be cast as List<IntPtr>");
            }
            list.Add(handle);

            return true;
        }

 [DllImport("user32.dll")]
        public static extern uint GetWindowThreadProcessId(IntPtr hWnd, out uint lpdwProcessId);

        [DllImport("user32.Dll")]
        [return: MarshalAs(UnmanagedType.Bool)]
        public static extern bool EnumChildWindows(IntPtr parentHandle, Win32Callback callback, IntPtr lParam);

        public delegate bool Win32Callback(IntPtr hwnd, IntPtr lParam);

        List<IntPtr> GetRootWindowsOfProcess(int pid)
        {
            List<IntPtr> rootWindows = GetChildWindows(IntPtr.Zero);
            List<IntPtr> dsProcRootWindows = new List<IntPtr>();
            foreach (IntPtr hWnd in rootWindows)
            {
                uint lpdwProcessId;
                GetWindowThreadProcessId(hWnd, out lpdwProcessId);
                if (lpdwProcessId == pid)
                    dsProcRootWindows.Add(hWnd);
            }
            return dsProcRootWindows;
        }

        public static List<IntPtr> GetChildWindows(IntPtr parent)
        {
            List<IntPtr> result = new List<IntPtr>();
            GCHandle listHandle = GCHandle.Alloc(result);
            try
            {
                Win32Callback childProc = new Win32Callback(EnumWindow);

                EnumChildWindows(parent, childProc, GCHandle.ToIntPtr(listHandle));
            }
            finally
            {
                if (listHandle.IsAllocated)
                    listHandle.Free();
            }
            return result;
        }

        private static bool EnumWindow(IntPtr handle, IntPtr pointer)
        {
            GCHandle gch = GCHandle.FromIntPtr(pointer);
            List<IntPtr> list = gch.Target as List<IntPtr>;
            if (list == null)
            {
                throw new InvalidCastException("GCHandle Target could not be cast as List<IntPtr>");
            }
            list.Add(handle);

            return true;
        }

im sory if its a bunch of code but idk what else can i do the error happends randomly on even win 10 or win 11 pls halp

Accord•2y ago

Looks like nothing has happened here. I will mark this as stale and this post will be archived until there is new activity.

maria 🌟•2y ago

ero•2y ago

what's the issue?

maria 🌟•2y ago

maria 🌟•2y ago

the windows desktop backgorunds turns black

ero•2y ago

in what circumstance

maria 🌟•2y ago

after a time i change the opacity of the icons

ero•2y ago

after what time, what do you change the opacity to come on provide even the least amount of info

maria 🌟•2y ago

the time i dont know more than 10 minutes maybie its random and its like a timer it starts when you change the opacity if you put the opacity to 50% it is 50% black and the other 50% the background if you put the opacity of the icons to 0% the desktop shows nice and if you put the opacity to 100% it just all black like if the desktop icons background becoming black instead of transparent for no reason aftrer x period of time very weird iusse

Jester•2y ago

i wouldnt have expected anyone to do this weird issue you have <:PES_Think:639363477458255874> i might take a better look at the code tmr

maria 🌟•2y ago

I sended the whole class if you want it on file i can send sory if the code is bad im not pro

maria 🌟•2y ago

ExplorerOpacity.cs

NativeMethods.cs

Jester•2y ago

id say make sure you are editing the correct window. does this have to be in c#? i think this would be easier to do in c

sibber•2y ago

so you just force explorer to be a layered window i cant imagine any world where that would work reliably

Jester•2y ago

yeah the desktop background is made up of a few windows and the icons is one of them you can pretty reliably make windows layered

sibber•2y ago

well, it depends on the app

Jester•2y ago

i think the issue might be that these windows are child windows and those dont always behave the same as normal windows

sibber•2y ago

but i imagine explorer assumes that no one will play around with the styles and it does some pretty not normal stuff with that assumption maybe for notepad or something, sure it could be reliable

Jester•2y ago

ive been messing with explorer windows, its probably "ok"

sibber•2y ago

but tbf ive never messed around with explorer

Jester•2y ago

it can also be that the explorer windows change their own styles now and then and thus overwrite your changes i have, bcuz im writing another program to modify my desktop

sibber•2y ago

well if it works it works

Jester•2y ago

i think this GetDesktopHwnd could maybe be improved

maria 🌟•2y ago

yea but it works for now but if you want to make some suggestions go ahead

maria 🌟•2y ago

this when desktop gets bugged and i put opacity to 100%