title: How to play Youtube video in ExoPlayer in Android?
body: <p>I am trying to play youtube video in exoplayer but here is some confusion I don't know what is DASH url, 
   I have only real youtube url like "<a href="https://www.youtube.com/watch?v=v1uyQZNg2vE" rel="noreferrer">https://www.youtube.com/watch?v=v1uyQZNg2vE</a>" , I have no idea how to generate dash url form real url.</p>
  
  <p>Dash Url:</p>
  
  <pre><code>new Sample("Google Glass",
          "http://www.youtube.com/api/manifest/dash/id/bf5bb2419360daf1/source/youtube?"
          + "as=fmp4_audio_clear,fmp4_sd_hd_clear&amp;sparams=ip,ipbits,expire,as&amp;ip=0.0.0.0&amp;"
          + "ipbits=0&amp;expire=19000000000&amp;signature=255F6B3C07C753C88708C07EA31B7A1A10703C8D."
          + "2D6A28B21F921D0B245CDCF36F7EB54A2B5ABFC2&amp;key=ik0", DemoUtil.TYPE_DASH),
  </code></pre>
  
  <p>Real Url :</p>
  
  <pre><code> https://www.youtube.com/watch?v=v1uyQZNg2vE
  </code></pre>