private static extern void toggl_on_sync_state( IntPtr context, TogglDisplaySyncState cb);
private static extern void toggl_on_sync_state( IntPtr context, TogglDisplaySyncState cb);
private static extern void toggl_on_sync_state( IntPtr context, TogglDisplaySyncState cb);
private static extern void toggl_on_sync_state( IntPtr context, TogglDisplaySyncState cb);