Looping a video with AVFoundation AVPlayer?

You can get a Notification when the player ends. Check AVPlayerItemDidPlayToEndTimeNotification

When setting up the player:

ObjC

  avPlayer.actionAtItemEnd = AVPlayerActionAtItemEndNone; 

  [[NSNotificationCenter defaultCenter] addObserver:self
                                           selector:@selector(playerItemDidReachEnd:)
                                               name:AVPlayerItemDidPlayToEndTimeNotification
                                             object:[avPlayer currentItem]];

this will prevent the player to pause at the end.

in the notification:

- (void)playerItemDidReachEnd:(NSNotification *)notification {
    AVPlayerItem *p = [notification object];
    [p seekToTime:kCMTimeZero];
}

this will rewind the movie.

Don’t forget un unregister the notification when releasing the player.

Swift

avPlayer?.actionAtItemEnd = .none

NotificationCenter.default.addObserver(self,
                                       selector: #selector(playerItemDidReachEnd(notification:)),
                                       name: .AVPlayerItemDidPlayToEndTime,
                                       object: avPlayer?.currentItem)

@objc func playerItemDidReachEnd(notification: Notification) {
    if let playerItem = notification.object as? AVPlayerItem {
        playerItem.seek(to: kCMTimeZero)
    }
}

Swift 4+

@objc func playerItemDidReachEnd(notification: Notification) {
    if let playerItem = notification.object as? AVPlayerItem {
        playerItem.seek(to: CMTime.zero, completionHandler: nil)
    }
}