title: Handle android listener events with RxJava 2
body: <p>I try to understand if it's possible to handle android listener events with RxJava 2. I guess, it is, but just couldn't find an answer.</p>
  
  <p>In my case I would like to handle speech recognition listener events.</p>
  
  <p>I only want to use RxJava 2 without any libraries.</p>
  
  <p>Thank you in adavance</p>