AVPlayer, notification for play/pause state?

Question

I'm searching for a way to get notified the exact moment when AVPlayer starts playing. There's the "rate" property, but currently I am checking it periodically with an NSTimer to get updates.

I tried KVO, but apparently it's not KVO compliant.

I know that there are events when the player ENDED. But i'm talking about pause here.

I also KVO subscribed to AVPlayerItem's "status", but it's showing me when the HTTP asset has finished caching, no play/pause. I also started collecting all calls of play/pause, requesting an instant UI update afterwards, but it takes some more runloops before AVPlayer really starts playing. I'd just love to update my button instantly.

Answer 1

Why do you say that "rate" is not KVO complaint? It works for me.

Here is what I did:

- (void)viewDidLoad
{
    ...

    [self.player addObserver:self forKeyPath:@"rate" options:0 context:nil];
}

And then:

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
if ([keyPath isEqualToString:@"rate"]) {
    if ([self.player rate]) {
        [self changeToPause];  // This changes the button to Pause
    }
    else {
        [self changeToPlay];   // This changes the button to Play
    }
}
}