Video Clip does not play correctly

I am trying to play a video in one of my screens. It seems to run but when the file opens, the fullscreen loads up and closes right after. The video is a few seconds long, and is m4v format. I added the framework and import开发者_高级运维ed the class. How can I make it so that the video plays properly?

My header:

-(IBAction)playMedia:(id)sender {

NSString *movieFile;
MPMoviePlayerController *moviePlayer;

movieFile = [[NSBundle mainBundle]
             pathForResource:@"movie" ofType:@"m4v"];
moviePlayer = [[MPMoviePlayerController alloc]
               initWithContentURL: [NSURL fileURLWithPath: movieFile]];

[moviePlayer.view setFrame:CGRectMake(145.0, 20.0, 155.0 , 100.0)];
[self.view addSubview:moviePlayer.view ];

[[NSNotificationCenter defaultCenter] addObserver:self
                                selector:@selector(playMediaFinished:)
                                name:MPMoviePlayerPlaybackDidFinishNotification
                                object:moviePlayer];
[moviePlayer play];

if ([toggleFullscreen isOn]) {
    [moviePlayer setFullscreen:YES animated:YES];
}
}

My implementation file is:

-(void)playMediaFinished: (NSNotification*)theNotfication {

MPMoviePlayerController *moviePlayer=[theNotfication object];

[[NSNotificationCenter defaultCenter] removeObserver:self
                            name:MPMoviePlayerPlaybackDidFinishNotification
                            object:moviePlayer];

[moviePlayer.view removeFromSuperview];
[moviePlayer release];

}

thanks