title: Closing scanner application/activity after a timeout
body: <p>I am using IntentIntegrator to initiate a scanner (QR/Barcode - zxing) application. I have a requirement to close the scanner application after 30 seconds of start.</p>
  
  <p>Scanner application is invoked through startActivityForResult. I am wondering if there is a way to get the reference of the activity started by "startActivityForResult", so that, I can use a timer and close the activity.</p>
  
  <p>Android experts, please help me here.</p>