Question

I make a iOS program to use the AVAudioPlayer to play music on the background. But I don’t know how to shut down the music after a certain time.
I try to use the UILocalNotification to stop music in the method:

- (void)application:(UIApplication *)app didReceiveLocalNotification:(UILocalNotification *)notification

But the way only effectly after the user recieved the Notification and click to shut down!

How can I stop the music automatically after a certain time?

Answer 1

If you use AVPlayer instead of AVAudioPlayer you can achieve this using addBoundaryTimeObserverForTimes:queue:usingBlock:

I have tried this with AVQueuePlayer (which is a subclass of AVPlayer) and it worked.

Try something like this:

id observer = [avPlayer addBoundaryTimeObserverForTimes:[NSArray arrayWithObject:[NSValue valueWithCMTime:CMTimeMake(60, 1)]] queue:NULL usingBlock:^{
        [avPlayer pause];
    }];

And somewhere later:

[avPlayer removeTimeObserver:observer];