How to add seek buttons on iOS lock screen?

Question

How to setup MPRemoteCommandCenter/MPNowPlayingInfoCenter to add seek buttons? Result that I want to achieve is on the screenshot. I have already added this code:

[[MPRemoteCommandCenter sharedCommandCenter].seekForwardCommand addTargetWithHandler:^MPRemoteCommandHandlerStatus(MPRemoteCommandEvent * _Nonnull event) {
    [weakSelf rewindForward];

    return MPRemoteCommandHandlerStatusSuccess;
}];
[MPRemoteCommandCenter sharedCommandCenter].seekForwardCommand.enabled = YES;

[[MPRemoteCommandCenter sharedCommandCenter].seekBackwardCommand addTargetWithHandler:^MPRemoteCommandHandlerStatus(MPRemoteCommandEvent * _Nonnull event) {
    [weakSelf rewindBackward];

    return MPRemoteCommandHandlerStatusSuccess;
}];
[MPRemoteCommandCenter sharedCommandCenter].seekBackwardCommand.enabled = YES;

Answer 1

You would also need to set preferredIntervals as described in https://stackoverflow.com/a/24818340/1514970.