/// <summary>
/// Sets glass background to custom margins in the window.
/// </summary>
/// <param name="win"></param>
public static void GlassBackground(this Window win, int left, int right, int top, int bottom)
{
// Why would you read the inner workings? Why? If you need to know why...
// DwmExtendFrameIntoClientArea http://msdn.microsoft.com/en-us/library/aa969512%28VS.85%29.aspx is the magical WINAPI call
// rest is just crap to get its parameters populated.
win.Loaded += delegate(object sender, RoutedEventArgs e)
{
try
{
// Obtain the window handle for WPF application
IntPtr mainWindowPtr = new WindowInteropHelper(win).Handle;
HwndSource mainWindowSrc = HwndSource.FromHwnd(mainWindowPtr);
// Transparent shall be glassed!
mainWindowSrc.CompositionTarget.BackgroundColor = System.Windows.Media.Colors.Transparent;
// Margin for the DwmExtendFrameIntoClientArea WINAPI call.
NonClientRegionAPI.MARGINS margins = new NonClientRegionAPI.MARGINS();
margins.cxLeftWidth = left;
margins.cxRightWidth = right;
margins.cyBottomHeight = bottom;
margins.cyTopHeight = top;
// Glass extend WINAPI thingie http://msdn.microsoft.com/en-us/library/aa969512%28VS.85%29.aspx form more details
int hr = NonClientRegionAPI.DwmExtendFrameIntoClientArea(mainWindowSrc.Handle, ref margins);
if (hr < 0)
{
//DwmExtendFrameIntoClientArea Failed
}
else
{
win.Background = System.Windows.Media.Brushes.Transparent;
}
}
// If not glassing capabilities (Windows XP...), paint background white.
catch (DllNotFoundException)
{
Application.Current.MainWindow.Background = System.Windows.Media.Brushes.White;
}
};
}
void OnLoaded(object sender, RoutedEventArgs e)
{
try
{
// Obtain the window handle for WPF application
IntPtr mainWindowPtr = new WindowInteropHelper(this).Handle;
HwndSource mainWindowSrc = HwndSource.FromHwnd(mainWindowPtr);
mainWindowSrc.CompositionTarget.BackgroundColor = Color.FromArgb(0, 0, 0, 0);
// Get System Dpi
System.Drawing.Graphics desktop = System.Drawing.Graphics.FromHwnd(mainWindowPtr);
float DesktopDpiX = desktop.DpiX;
float DesktopDpiY = desktop.DpiY;
// Set Margins
NonClientRegionAPI.MARGINS margins = new NonClientRegionAPI.MARGINS();
// Extend glass frame into client area
// Note that the default desktop Dpi is 96dpi. The margins are
// adjusted for the system Dpi.
margins.cxLeftWidth = Convert.ToInt32(5 * (DesktopDpiX / 96));
margins.cxRightWidth = Convert.ToInt32(5 * (DesktopDpiX / 96));
margins.cyTopHeight = Convert.ToInt32(((int)topBar.ActualHeight + 5) * (DesktopDpiX / 96));
margins.cyBottomHeight = Convert.ToInt32(5 * (DesktopDpiX / 96));
int hr = NonClientRegionAPI.DwmExtendFrameIntoClientArea(mainWindowSrc.Handle, ref margins);
//
if (hr < 0)
{
//DwmExtendFrameIntoClientArea Failed
}
}
// If not Vista, paint background white.
catch (DllNotFoundException)
{
Application.Current.MainWindow.Background = Brushes.White;
}
}