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
}
}
}