title: Way to check hardware buttons in background service
body: <p>I am making SOS app that sends emails/SMSs to contacts you add if you hit combination of hardware buttons even if app is not running (for example volumeUp volumeDown volumeUp) and sends your location to contacts you added. For as much as I found out that is Impossible because </p>
  
  <ol>
  <li>It is impossible to listen for hardware buttons in background service</li>
  <li>You cant check for combination of buttons only for 1 even if you are in Activity</li>
  </ol>