Question

I have a large C++ codebase with native Windows GUI that runs fullscreen.
A part of it shall be exchanged by a WPF window shown on top of it.
The window is set up like this:

<Window WindowState="Normal" 
        WindowStyle="None"
        ShowInTaskbar="False"
        AllowsTransparency="True"
/>

This blends the window seamless into the rest of the application.
The invocation of the window is done from C++/CLI like this:

Windows::Window^ w = window();
Windows::Interop::WindowInteropHelper iHelp(w);
iHelp.Owner = System::IntPtr(_parentHwnd);
w->Show();

The _parentHwnd is the HWND of the native application.
As said the application is always shown fullscreen.
When I now click on the WPF window the Windows taskbar will appear.
How do I prevent the taskbar from appearing?

Answer 1

I have used this class (an idea was found somewhere on the Net) to hide/show the taskbar:

public static class Taskbar
{
    [DllImport("user32.dll")]
    private static extern int FindWindow(string className, string windowText);
    [DllImport("user32.dll")]
    private static extern int ShowWindow(int hwnd, int command);

    private const int SW_HIDE = 0;
    private const int SW_SHOW = 1;

    public static int Handle
    {
        get
        {
            return FindWindow("Shell_TrayWnd", "");
        }
    }
    public static int StartHandle
    {
        get
        {
            return FindWindow("Button", "Start");
        }
    }

    public static void Show()
    {
        ShowWindow(Handle, SW_SHOW);
        ShowWindow(StartHandle, SW_SHOW);
    }

    public static void Hide()
    {
        ShowWindow(Handle, SW_HIDE);
        ShowWindow(StartHandle, SW_HIDE);
    }
}

Works on Windows XP/Vista/7.