SPTAppRemoteLibraryState Protocol Reference
SPTAppRemoteLibraryState represents a the state of an album or track in a users Spotify library.
The uri of the track or album
@property (nonatomic, strong, readonly) NSString *uri
YES album or track was added, otherwise
@property (nonatomic, assign, readonly) BOOL isAdded
YES album or track can be added, otherwise
@property (nonatomic, assign, readonly) BOOL canAdd