AVPlayer得到了元数据，但不打(AVPlayer got the metadata but n

我试图做一个非常简单的应用，目的是听音频流（AAC 64kbps的 ）。 要做到这一点我使用AVPlayer从Apple AVFoundation具有如下：

ViewController.m

#import "ViewController.h"
@interface ViewController ()
@end

@implementation ViewController
@synthesize playerItem, player;

- (void)viewDidLoad
{
    [super viewDidLoad];
}

- (void) viewWillAppear:(BOOL)animated{
    [super viewWillAppear:animated];
    playerItem = [AVPlayerItem playerItemWithURL:[NSURL URLWithString:@"http://stream.myjungly.fr/MYJUNGLY2"]];
    [playerItem addObserver:self forKeyPath:@"timedMetadata" options:NSKeyValueObservingOptionNew context:nil];

    player = [AVPlayer playerWithPlayerItem:playerItem];
    [player play];

    NSLog(@"player item error : %@", playerItem.error.description);
    NSLog(@"player error : %@", player.error.description);
}

- (void) observeValueForKeyPath:(NSString*)keyPath ofObject:(id)object
                     change:(NSDictionary*)change context:(void*)context {

    if ([keyPath isEqualToString:@"timedMetadata"])
    {
        AVPlayerItem* _playerItem = object;
        for (AVMetadataItem* metadata in _playerItem.timedMetadata)
        {
            NSLog(@"\nkey: %@\nkeySpace: %@\ncommonKey: %@\nvalue: %@", [metadata.key description], metadata.keySpace, metadata.commonKey, metadata.stringValue);
        }
    }
}

@end

我的目标player和playerItem都很强属性：

ViewController.h

@interface ViewController : UIViewController

@property (nonatomic, strong) AVPlayerItem* playerItem;
@property (nonatomic, strong) AVPlayer* player;

@end

键值观察是伟大的工作，这是我的日志：

2013-05-14 11:18:03.725 MusicAvPlayer[6494:907] player item error : (null)
2013-05-14 11:18:03.728 MusicAvPlayer[6494:907] player error : (null)
2013-05-14 11:18:08.140 MusicAvPlayer[6494:907] 
key: title
keySpace: comn
commonKey: title
value: Alabama Shakes - Be Mine

但音频不打，我有去没声音！ 任何想法，为什么？

编辑：我已经看这个问题：

没有声音从AVPlayer未来

AVAudioPlayer，无声音

AVAudioPlayer不打任何声音

这就是为什么我使用的是强大的属性，所以我想我的问题不是圆弧相关

Answer 1:

我发现了问题：iPhone在静音模式......所以没有声音可以走出去，在扬声器的声音被打时，我用的是头手机。

但我有一个新的问题，现在：你怎么能播放声音的喇叭，当手机处于静音模式？ （如官方音乐应用程序）

编辑：...答案是没有： 即使在静音模式下播放声音的iPhone

Answer 2:

// Init PlayerItem
playerItem = [AVPlayerItem playerItemWithURL:[NSURL URLWithString:@"http://stream.myjungly.fr/MYJUNGLY2"]];

// Init Player Obj
player = [AVPlayer playerWithPlayerItem:playerItem];
// Add objserver on Player
[player addObserver:self forKeyPath:@"status" options:0 context:nil];

添加观测器方法的类

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object
                        change:(NSDictionary *)change context:(void *)context {
    if (object == player && [keyPath isEqualToString:@"status"]) {
        if (player.status == AVPlayerStatusReadyToPlay) {
            // Start playing...
            [player play];
        } else if (player.status == AVPlayerStatusFailed) {
            // something went wrong. player.error should contain some information
        }
    }
    if ([keyPath isEqualToString:@"timedMetadata"])
    {
        AVPlayerItem* _playerItem = object;
        for (AVMetadataItem* metadata in _playerItem.timedMetadata)
        {
            NSLog(@"\nkey: %@\nkeySpace: %@\ncommonKey: %@\nvalue: %@", [metadata.key description], metadata.keySpace, metadata.commonKey, metadata.stringValue);
        }
    }

}

文章来源: AVPlayer got the metadata but not playing