为什么视频在iPhone的MPMoviePlayer上没有声音播放

Question

我正在使用MPMoviePlayer在我的应用程序中播放本地视频文件。文件是.mov格式。当我在模拟器中运行我的应用程序时，它工作正常。但是当我在没有声音的iPhone视频中运行它时。这是我的代码，

self.currUrl = [NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"Gun_Shot" ofType:@"mov"]]; 
    if (self.mpc) 
    { 
     [self.mpc release]; 
     self.mpc = nil; 
    } 
    self.mpc = [[MPMoviePlayerController alloc] 
      initWithContentURL:self.currUrl]; 
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(moviePlayBackDidFinish:) name:MPMoviePlayerPlaybackDidFinishNotification object:self.mpc]; 
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(moviePlayBackLoadStateDidChange:) name:MPMoviePlayerLoadStateDidChangeNotification object:self.mpc]; 
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(moviePlayBackDidEnterFullScreen:) name:MPMoviePlayerDidEnterFullscreenNotification object:self.mpc];  
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(moviePlayBackDidExitFullScreen:) name:MPMoviePlayerDidExitFullscreenNotification object:self.mpc]; 
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(moviePlayBackNowPlayingContinues:) name:MPMoviePlayerNowPlayingMovieDidChangeNotification object:self.mpc]; 
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(moviePlayBackStateChanged:) name:MPMoviePlayerPlaybackStateDidChangeNotification object:self.mpc]; 

    self.mpc.controlStyle = MPMovieControlStyleNone; 
    self.mpc.shouldAutoplay = NO; 
    self.mpc.view.frame = CGRectMake(0, 0, self.mpView.frame.size.width, self.mpView.frame.size.height); 
    [self.mpView addSubview:self.mpc.view]; 
    [self.mpView bringSubviewToFront:self.topMainView]; 
    [self.mpView bringSubviewToFront:self.bottomMainView]; 
    [self.mpc prepareToPlay]; 
    self.timeLbl.text = [NSString stringWithFormat:@"%f Sec(s)", self.mpc.duration]; 

我不明白为什么视频在iPhone上运行应用程序时变为静音。任何帮助将不胜感激。

Answer 1

不看你的代码。其中一个原因可能是您的iPhone处于静音模式。

这个answer也可能帮助你。