how to add MPMediaItem to MPMediaItemCollection
<p>I hope to play MPMediaItemcollection using MPMusicPlayerController</p>

<pre><code>musicPlayer = [MPMusicPlayerController applicationMusicPlayer];
</code></pre>

<p>I have got the handler of MPMediaItem *mediaItem</p>

<p>How can I add MPMediaItem to MPMediaItemCollection?
I try addObject but no function.</p>

<p>Thanks</p>
