private static void RegisterEvent (int eventId, Delegate managedHandler, UnmanagedEventHandler nativeHandler)
{
if (managedHandler == null)
return;
IntPtr t = NativeMethods.surface_get_time_manager (Deployment.Current.Surface.Native);
int token = Events.AddHandler (t, eventId, nativeHandler);
EventList.AddHandler (eventId, token, managedHandler, nativeHandler);
}