private void JoystickViewer_FormClosed(object sender, FormClosedEventArgs e)
{
// dispose of GDI resources
jsOn.Dispose(); jsOn = null;
jsOff.Dispose(); jsOff = null;
crosshairs.Dispose(); crosshairs = null;
menuFont.Dispose();
// tell the background thread to terminate
done = true;
// dispose of the device object
dev.Dispose();
}