MPMoviePlayerViewController播放在线视频的时候为啥总是加载不出来？

#import <MediaPlayer/MediaPlayer.h>
@interface ViewController (){
    MPMoviePlayerViewController *_moviePlayerController;
}

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    UIButton * btn = [UIButton buttonWithType:UIButtonTypeCustom];
    btn.frame = CGRectMake(100, 100, 100, 100);
    btn.backgroundColor = [UIColor redColor];
    [btn addTarget:self action:@selector(pressBtn) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:btn];

}
-(void)pressBtn
{
    NSURL *url = [NSURL URLWithString:@"http://221.229.165.31:80/play/274CF5C996AFCE2C751D315B5D1BF131B8C08208/298088%5Fstandard.mp4"];
 
    _moviePlayerController = [[MPMoviePlayerViewController alloc] initWithContentURL:url];
    
    _moviePlayerController.moviePlayer.controlStyle = MPMovieControlStyleFullscreen;

    [_moviePlayerController.moviePlayer prepareToPlay];
  
    [_moviePlayerController.moviePlayer play];
    _moviePlayerController.moviePlayer.backgroundView.backgroundColor=[UIColor whiteColor];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(my:) name:MPMoviePlayerLoadStateDidChangeNotification object:nil];
    
    [self presentMoviePlayerViewControllerAnimated:_moviePlayerController];
}
-(void)my:(NSNotification *)noti
{
    NSLog(@"%lu",(unsigned long)_moviePlayerController.moviePlayer.loadState);
}

每次都是加载一点然后就不加载了，也不是网速的问题，直接在模拟器的浏览器输入网址就可以播放。这是什么原因

---

我用AVPlayer很正常：

/// setup player
NSURL *url = [NSURL URLWithString:@"http://221.229.165.31:80/play/274CF5C996AFCE2C751D315B5D1BF131B8C08208/298088%5Fstandard.mp4"];

AVPlayerItem *item = [AVPlayerItem playerItemWithURL:url];
AVPlayer *player = [AVPlayer playerWithPlayerItem:item];
    
_player = player;
AVPlayerLayer *layer = [AVPlayerLayer playerLayerWithPlayer:player];
layer.frame = _playerView.bounds;
layer.videoGravity = AVLayerVideoGravityResizeAspect;
    
[_playerView.layer addSublayer:layer];


/// play video
[_player play];

---

MPMoviePlayerViewController下的self·view在arc下被提前释放了，将self.view 设置为全局的就可以播放出来了，试一下吧！可以的话点?