iPhone SDK 4: weird compilation error, MPMoviePlayerController
<p>I have a viewController containing the following method:</p>

<pre><code>- (IBAction) playMovie {
    NSURL *url = [NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"test" ofType:@"m4v"]];

    MPMoviePlayerController *moviePlayer = [[MPMoviePlayerController alloc] initWithContentURL:url];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(moviePlayBackDidFinish:)
                                       name:MPMoviePlayerPlaybackDidFinishNotification
                                       object:moviePlayer];

    moviePlayer.controlStyle = MPMovieControlStyleNone;
    moviePlayer.shouldAutoplay = YES;

    [self.view addSubview:moviePlayer.view];
    [moviePlayer setFullscreen:YES animated:YES];
}
</code></pre>

<p>I can't compile the code because of the error:</p>

<p>Undefined symbols:
  "_MPMoviePlayerPlaybackDidFinishNotification", referenced from:
      _MPMoviePlayerPlaybackDidFinishNotification$non_lazy_ptr in AnotherViewController.o
     (maybe you meant: _MPMoviePlayerPlaybackDidFinishNotification$non_lazy_ptr)
  "_OBJC_CLASS_$_MPMoviePlayerController", referenced from:
      objc-class-ref-to-MPMoviePlayerController in AnotherViewController.o
ld: symbol(s) not found
collect2: ld returned 1 exit status</p>

<p>This message doesn't make sense to me.</p>

<p>I was intended to use this method as a part of a view controller. Do I have to create a separate view controller for the player or it's not the case?</p>

<p>I worked with SDK 3.1.2 when I created this project but the playMovie method was completely rewritten according to new API rules. The current SDK version is 4.0.1</p>
