Window Overlay Adorner Overrides

gistfile1.cs

private static readonly Brush screenBrush_ = new SolidColorBrush(Color.FromArgb(0x7f, 0x7f, 0x7f, 0x7f));

protected override void OnRender(DrawingContext drawingContext)
{
    drawingContext.DrawRectangle(screenBrush_, null, WindowRect());
    base.OnRender(drawingContext);
}

protected override Geometry GetLayoutClip(Size layoutSlotSize)
{
    // Add a group that includes the whole window except the adorned control
    GeometryGroup grp = new GeometryGroup();
    grp.Children.Add(new RectangleGeometry(WindowRect()));
    grp.Children.Add(new RectangleGeometry(new Rect(layoutSlotSize)));

    return grp;
}