title: Error creating MediaPlayer with Uri or file in assets
body: <p>I copied song.mp3 to my project's assets directory and wrote this code:</p>
  
  <pre><code>private MediaPlayer mp;
  
  Uri uri = Uri.parse("file:///android_asset/song.mp3");
  
  mp=MediaPlayer.create(this, uri);
  </code></pre>
  
  <p>After running the create statement, the variable mp is null.  What is wrong?</p>
  
  <p>Thanks.</p>