视频不能在MPMoviePlayerController上播放

如何解决视频不能在MPMoviePlayerController上播放

| 我想获取iPhone中视频的总时长。我正在使用以下代码来获取持续时间

videoPath = [videoPath stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSURL *url = [NSURL URLWithString:videoPath];
MPMoviePlayerController *mpPlayer = [[[MPMoviePlayerController alloc] initWithContentURL:url] autorelease]; 
mpPlayer.view.frame = CGRectMake(0,320,100);
[self.view addSubview:mpPlayer.view];
NSLog(@\"duration = %f\",mpPlayer.duration);
[mpPlayer play];

但我不知道为什么我无法获取视频的时长，也无法播放视频。 谁能帮助我找到解决此问题的方法。 提前致谢。

解决方法

提示： 持续时间可能在实际播放之前不可用->收到

MPMoviePlayerPlaybackStateDidChangeNotification

（出于安全考虑，the2ѭ）时，请再次检查持续时间。,请检查视频路径是否正确，并检查播放器是否分配了正确的文件网址,

    videoPath = [videoPath stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
    NSURL *url = [NSURL URLWithString:videoPath];
    MPMoviePlayerController *mpPlayer = [[[MPMoviePlayerController alloc] initWithContentURL:url] autorelease]; 
    mpPlayer.view.frame = CGRectMake(0,320,100);
    [self.view addSubview:mpPlayer.view];
    NSLog(@\"duration = %f\",mpPlayer.duration);
    [mpPlayer play];

//add notifications


  [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(MPMoviePlayerLoadStateDidChange:) name:MPMoviePlayerLoadStateDidChangeNotification object:nil];

- (void)MPMoviePlayerLoadStateDidChange:(NSNotification *)notification {

    if ((moviePlayer.loadState & MPMovieLoadStatePlaythroughOK) == MPMovieLoadStatePlaythroughOK) {
duration = mpPlayer.duration;
NSLog(@\"duration = %f\",mpPlayer.duration);
}
}