\[MediaRemote\] Error Operation requires a client callback to have been registered. requesting playback queue

Question

I'm currently learning Swift and I am creating an app for a webradio.

I get an error when calling this code :

MPNowPlayingInfoCenter.default().nowPlayingInfo = [
    MPMediaItemPropertyArtist: currentTrack.artist,
    MPMediaItemPropertyTitle: currentTrack.title,
    MPMediaItemPropertyArtwork: albumArtwork,
    MPNowPlayingInfoPropertyIsLiveStream: 1.0,
    MPNowPlayingInfoPropertyMediaType: 1.0,
    MPNowPlayingInfoPropertyPlaybackQueueIndex: 0,
    MPNowPlayingInfoPropertyPlaybackQueueCount: 0
]

Here's the error :

[MediaRemote] Error Operation requires a client callback to have been registered. requesting playback queue

Does anyone knows why? I'm French so I don't correctly understand this error but what I can understand is that something could be missing? If yes, what?

Thanks to all for helping!

Answer 1

I opened a Technical Support Incident with Apple's developer teams and they replied to me :

Hello Didier,

The engineering team came back and said that the fact you are seeing those log messages is actually a bug in the system framework and do not mean you are incorrectly using the MPNowPlayingInfoCenter API. You should use the MPRemoteCommandSample sample code project as a reference when updating your application as it highlights the engineering recommended best practices when using the MPNowPlayingInfoCenter APIs.

Best Regards,

Developer Technical Support Apple Worldwide Developer Relations