CAAnimation delegate methods not called

Question

I am having an issue with iOS CABasicAnimation. No matter what I do, I cannot get the methods animationDidStart: and animationDidStop:finished: to fire. My class is subclassing CAShapeLayer and is performing the animations inside of it:

- (void)start{
    [self removeAllAnimations];

    CABasicAnimation *pathAnimation = [self makeAnimationForKey:@"strokeEnd"];
    [self addAnimation:pathAnimation forKey:@"strokeEnd"];
}

- (CABasicAnimation *)makeAnimationForKey:(NSString *)key {
    CABasicAnimation *anim = [CABasicAnimation animationWithKeyPath:key];
    anim.fromValue = [NSNumber numberWithFloat:0.f];
    anim.toValue = [NSNumber numberWithFloat:1.f];

    anim.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear];
    anim.duration = self.duration;
    anim.delegate = self;
    return anim;
}

- (void)animationDidStart:(CAAnimation *)anim{
    NSLog(@"HERE START");
}

- (void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag{
    NSLog(@"HERE STOP");
}

Any tips or help would be appreciated, thanks in advance!

Answer 1

you must set delegate before assigning animation to layer:

popIn.delegate = self;
[annotation.layer addAnimation:popIn forKey:@"popIn"];

Swift 5.4.2

popIn.delegate = self
annotation.layer.add(transition, forKey:"popIn")

Answer 2

Ok so it turns in my subclass I had a property called duration. Even though it is not documented as being apart of CALayer, duration is a part of one of it's protocols called CAMediaTiming. The methods were never fired because the property was being overwritten via my subclass.