检测AVPlayer何时达到总持续时间的特定播放百分比?

最好的观察方式可能是使用 periodTimeObserver docs

func addPeriodicTimeObserver() {
    // Invoke callback every half second
    let interval = CMTime(seconds: 0.5,
                          preferredTimescale: CMTimeScale(NSEC_PER_SEC))
    // Queue on which to invoke the callback
    let mainQueue = DispatchQueue.main
    // Add time observer
    timeObserverToken =
        player.addPeriodicTimeObserver(forInterval: interval, queue: mainQueue) {
            [weak self] time in
            // Check whether the time has reached half of duration
    }
}