如何将苹果音乐上所有可用的播放列表添加到我的项目中

Question

如何将苹果音乐上所有可用的播放列表添加到我的项目中。我想访问所有的苹果音乐播放列表，目前我正在使用MPMediaLibrary获取播放列表的方法，但没有获得任何数据或错误？

`func getUserPlaylist()
    {
MPMediaLibrary.requestAuthorization { (status) in
print(status)
        }
        let lib = MPMediaLibrary()
       // let name = "playlist name"
       // let id:NSUUID = NSUUID()
       // let metadata = MPMediaPlaylistCreationMetadata.init(name: name)
       // metadata.authorDisplayName = "author"
       // metadata.descriptionText = "description"
        lib.getPlaylist(with:id as UUID, creationMetadata: nil) { (playlist, error) in
            guard error == nil
                else
            {
                print(error.debugDescription)
                return
            }
            if let currentPlaylist = playlist
            {
                print(currentPlaylist.name)
            }
        }
    } `

Answer 1

要访问苹果的音乐库，您需要在info.plist中添加“隐私-媒体库使用说明”。然后，您需要使您的类符合MPMediaPickerControllerDelegate。要显示Apple Music库，需要显示MPMediaPickerController。要将歌曲添加到数组中，需要实现MPMediaPickerControllerDelegate的didPickMediaItems方法。

    class MusicPicker:UIViewController, MPMediaPickerControllerDelegate {
//the songs the user will select
var selectedSongs: [URL]!

//this method is to display the music library. You might call it when a user taps a button to add songs to their playlist
func getSongs() {

var mediaPicker: MPMediaPickerController?

mediaPicker = MPMediaPickerController(mediaTypes: .music)

mediaPicker?.delegate = self

mediaPicker?.allowsPickingMultipleItems = true

mediaPicker?.showsCloudItems = false
//present the music library
present(mediaPicker!, animated: true, completion: nil)

    }

    //this is called when the user selects songs from the library
    func mediaPicker(_ mediaPicker: MPMediaPickerController, didPickMediaItems mediaItemCollection: MPMediaItemCollection) {
      //these are the songs that were selected. We are looping over the choices
      for mpMediaItem in mediaItemCollection.items {
 //the song url, add it to an array
let songUrl = mpMediaItem.assetURL
selectedSongs.append(songURL)
       }
       //dismiss the Apple Music Library after the user has selected their songs
       dismiss(animated: true, completion: nil)

       }
       //if the user clicks done or cancel, dismiss the Apple Music library
       func mediaPickerDidCancel(mediaPicker: MPMediaPickerController) {

      dismiss(animated: true, completion: nil)
    }
       }

Answer 2

我使用下面的代码获得了所有的播放列表，我使用了MPMediaQuery类。

let query: MPMediaQuery = MPMediaQuery.playlists()
        let playlists = query.collections
        guard playlists != nil else{
            return
        }
        for collection in playlists!{
            print(playlists?.description)
        }