title: Xamarin Native equivalent of Xamarin.Forms App OnSleep and OnResume
body: <p>I'm working with a Xamarin Native application, and would like to perform some logic when the application is focused / out of focused in android - similar to Xamarin.Forms <code>Application.OnSleep()</code>, and <code>Application.OnResume()</code> (not to be confused with <code>Activity.OnResume</code>, and <code>Activity.OnPause</code>)</p>
  
  <p>Just wondering what solution others have used to solve this scenario (besides migrating to Xamarin.Forms).</p>