title: Android - Use the Activity callback in a standard java class
body: <p>I'm developing an .aar library and I really need to interact with the lifecycle of an activity (so the <code>callback</code> <code>onCreate()</code>, on <code>onResume()</code>, etc...) in a standard java class.
  I tried a lot of things but nothing works.
  Is there a way I can do that?</p>