title: continue playing music when app closes
body: <p>I am developing an app in wp7 and in some part.</p>
  
  <p>I start a mediaelement to play my music file from isolated storage, with available functions(play, pause, next, previous, seek) and all goes perfect!</p>
  
  <p>Now i want to make the app continue playing on user-exit or page-unload or something like that when mediaelement already playing!</p>
  
  <p>Notice in the abobe try the</p>
  
  <pre>
  list.playlist: is a list with audiotracks
  num_input: is the number of music file in list that will play, (get: from mediaelement)
  time_input: is the timespan from mediaelement before stop, (set: backgroundaudioplayer to start)
  play: is boolean variable, true if mediaelement plays
  Stop(): is function that stops mediaelement from playing
  </pre>
  
  <p>Thats i am trying is:</p>
  
  <pre><code>private void PhoneApplicationPage_Unloaded(object sender, RoutedEventArgs e)
  {
      if (play == true)
      {
          TimeSpan time_input = med.Position;
          Stop();
  
          BackgroundAudioPlayer.Instance.Close();
          BackgroundAudioPlayer.Instance.Track = list.playlist[num_input];
          BackgroundAudioPlayer.Instance.Position = time_input;
          if (PlayState.Playing == BackgroundAudioPlayer.Instance.PlayerState) {       BackgroundAudioPlayer.Instance.Pause(); }
          else { BackgroundAudioPlayer.Instance.Play(); }
          }
  }
  
  void Instance_PlayStateChanged(object sender, EventArgs e)
  {
      switch (BackgroundAudioPlayer.Instance.PlayerState)
      {
          case PlayState.Playing:
              break;
  
          case PlayState.Paused:
          case PlayState.Stopped:
              break;
       }
  }
  </code></pre>
  
  <p>The problem is that when the app page-unload (not on user exit, the first problem)
  the backgroundaudioplayer gets the name and the EnabledControls and all staff but it isn't playing even I press the play button(so buttons not working, second problem)!</p>
  
  <p>Also i want to control the list of my app beside that player(previous, next, play, pause) even the app is closed!</p>
  
  <p>All the songs are located in isolated and i have the song-name and file-name in database. The audio track looks like:</p>
  
  <pre><code>AudioTrack audiotrack1 = new AudioTrack(new Uri(emp.EmployeeFile + ".mp3", UriKind.Relative), emp.EmployeeName, null, null, null, null, EnabledPlayerControls.All);
  </code></pre>
  
  <p>Thanks!</p>