Ios SKCloudServiceCapability的Swift 3.1问题

我正在尝试调用此函数来检查Apple Music订阅状态。我有一个活跃的订阅，在我的iPhone上听音乐。 但当我在上面运行测试应用程序时，

capability

值无效

它应该是

skcloudservicepability.musicCatalogPlayback

，

skcloudservicepability.addToCloudMusicLibrary

，或者未设置。我只能得到

原始值=257

func appleMusicCheckIfDeviceCanPlayback()
{
    let serviceController = SKCloudServiceController()
    serviceController.requestCapabilities { (capability:SKCloudServiceCapability, err:Error?) in
        switch capability {
        case SKCloudServiceCapability.musicCatalogPlayback:
            print("The user has an Apple Music subscription and can playback music!")
        case SKCloudServiceCapability.addToCloudMusicLibrary:
            print("The user has an Apple Music subscription, can playback music AND can add to the Cloud Music Library")
        case []:
            print("The user doesn't have an Apple Music subscription available. Now would be a good time to prompt them to buy one?")
        default: print("Something went wrong")
        }
    }
}

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这里怎么了？

最后，苹果论坛的人给了我这个文档链接，我发现了这个问题。

我应该使用if capability.contains（skcloudservicepability.）而不是转换为性能值。 所以这段代码运行得很好

func appleMusicCheckIfDeviceCanPlayback()  
{  
    let serviceController = SKCloudServiceController()  
    serviceController.requestCapabilities { (capability:SKCloudServiceCapability, err:Error?) in  
        if capability.contains(SKCloudServiceCapability.musicCatalogPlayback) {  
            print("The user has an Apple Music subscription and can playback music!")  

        } else if  capability.contains(SKCloudServiceCapability.addToCloudMusicLibrary) {  
            print("The user has an Apple Music subscription, can playback music AND can add to the Cloud Music Library")  

        } else {  
            print("The user doesn't have an Apple Music subscription available. Now would be a good time to prompt them to buy one?")  

        }  
    }  
}  

这是位算术

.musicCatalogPlayback(1 << 0 = 1) | . addToCloudMusicLibrary(1 << 8 = 256) = 257

oc:

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在苹果发展论坛上问到同样的问题：

swift:

case SKCloudServiceCapability.addToCloudMusicLibrary|SKCloudServiceCapability.musicCatalogPlayback:{
    //code
}break;

case SKCloudServiceCapabilityAddToCloudMusicLibrary|SKCloudServiceCapabilityMusicCatalogPlayback:{
            //code
        }break;