ios - Apple Music API，“电台”资源类型播放

Question

我正在尝试播放 Apple Music Catalogue 中的“电台”资源。

我通过 Apple Music API 检索广播电台，即搜索目录资源

这给了我一个电台响应（StationResponse）：

{
  attributes =   {
    artwork =     {
      bgColor = ff9f0e;
      height = 1080;
      textColor1 = 0f0800;
      textColor2 = 190a00;
      textColor3 = 3f2603;
      textColor4 = 472802;
      url = "https://is4-ssl.mzstatic.com/image/thumb/Features111/v4/cd/ea/5a/cdea5a14-9789-26f5-8714-17b1db8f1021/source/{w}x{h}sr.jpeg";
      width = 4320;
    };
    editorialNotes =     {
      name = "Pure Country";
      short = "Today's biggest hits.";
    };
    isLive = 0;
    name = "Pure Country";
    playParams =     {
      format = tracks;
      id = "ra.985486583";
      kind = radioStation;
      stationHash = CgkIBBoF96n11QMQAg;
    };
    url = "https://music.apple.com/ca/station/pure-country/ra.985486583";
  };
  href = "/v1/catalog/ca/stations/ra.985486583";
  id = "ra.985486583";
  type = stations;
}

通常，对于其他类型的目录资源（播放列表、专辑、歌曲），我采用 'id' 值并将其设置在 ```MPMusicPlayerController` 的播放队列中并开始播放，即：

- (void)beginPlaybackForStoreID:(NSString *)storeID
{
    __weak typeof(self) weakSelf = self;
    dispatch_async(dispatch_get_main_queue(), ^{
        if (@available(iOS 9.3, *)) {
            __strong typeof(self) strongSelf = weakSelf;
            // Store id for 'pure-country' radio station is: ra.985486583
            // https://music.apple.com/ca/station/pure-country/ra.985486583
            [strongSelf.musicPlayerController setQueueWithStoreIDs:@[storeID]];
            [strongSelf.musicPlayerController play];
        } else {
            // Fallback on earlier versions
            NSLog(@"Not able to setQueueWithStoreIDs on this version of iOS");
        }
    });

}

'musicPlayerController' 是系统音乐播放器MPMusicPlayerController的一个实例

仅当“id”属于广播电台时，我才会收到此错误。

2020-05-20 10:37:42.681961-0700 ---[61653:10276450] [RemoteControl] userIdentityForMediaRemoteOptions -❗️No user identity data. Using active account.
2020-05-20 10:37:42.774906-0700 ---[61653:10276375] Audio session options array to bitmask: 1
2020-05-20 10:37:43.359056-0700 ---[61653:10276523] [SDKPlayback] 
-[MPMusicPlayerController prepareToPlayWithCompletionHandler:] completed id=systemMusicPlayer error: 
Error Domain=MPCPlayerRequestErrorDomain Code=1000 "Failed to send command 122" 
UserInfo={NSDebugDescription=Failed to send command 122, 
NSUnderlyingError=0x281170150 {Error Domain=MPCPlayerRequestErrorDomain Code=1000 "Failed to send command 122 (MRMediaRemoteCommandHandlerStatus = 2)" 
UserInfo={NSDebugDescription=Failed to send command 122 (MRMediaRemoteCommandHandlerStatus = 2), 
MPCPlayerErrorKeyMediaRemoteCommandHandlerStatus=2}}}

播放电台有不同的机制吗？例如，也许使用 AVPlayer 流式传输电台？

我注意到站响应中的“playParams”包含其他资源类型不包含的两个属性：“格式”和“站哈希”。

我似乎在 Apple 的文档中找不到有关流媒体广播电台的任何内容。

标签： iosobjective-cmpmusicplayercontrollerapple-musicapple-musickit