WPF: How do I make a custom modal dialog flash?

Question

Normally when you open a Modal Dialog and try to click on it\'s parent window the Modal Dialog\'s titlebar flashes. When creating a custom, borderless, chromeless, window in

Answer 1

private IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
    {
        var retVal = IntPtr.Zero;

        switch (msg)
        {
            case UnsafeNativeConstants.WM_NCACTIVATE:
                retVal = UnsafeNativeMethods.DefWindowProc(hwnd, UnsafeNativeConstants.WM_NCACTIVATE, new IntPtr(1), new IntPtr(-1));
                AssociatedObject.UpdateTitlebar((int)wParam == 1 ? true : false);
                handled = true;
                break;
        }

        return retVal;
    }

The WndProc I have hooked up in a custom behavior that's attached to my window. It calls an internal method on my window that will update the color of the Titlebar appropriately.

Thanks to @Hans Passant for pointing me in the right direction.