rotate a UIView around its center but several times

You can use the following animation on your UIView's layer property. I've tested it.

Objective-C

UIView *viewToSpin = ...;    CABasicAnimation* spinAnimation = [CABasicAnimation                                  animationWithKeyPath:@"transform.rotation"];spinAnimation.toValue = [NSNumber numberWithFloat:5*2*M_PI];[viewToSpin.layer addAnimation:spinAnimation forKey:@"spinAnimation"];

Swift 5.0

let viewToSpin = UIView() // However you have initialized your viewlet spinAnimation = CABasicAnimation.init(keyPath: "transform.rotation")spinAnimation.toValue = NSNumber(value: 5.0 * 2.0 * Float.pi)viewToSpin.layer.add(spinAnimation, forKey: "spinAnimation")

As Brad Larson indicated, you can do this with a CAKeyframeAnimation. For instance,

CAKeyframeAnimation *rotationAnimation;rotationAnimation =    [CAKeyframeAnimation animationWithKeyPath:@"transform.rotation.z"];rotationAnimation.values = [NSArray arrayWithObjects:                            [NSNumber numberWithFloat:0.0 * M_PI],                             [NSNumber numberWithFloat:0.75 * M_PI],                             [NSNumber numberWithFloat:1.5 * M_PI],                             [NSNumber numberWithFloat:2.0 * M_PI], nil]; rotationAnimation.calculationMode = kCAAnimationPaced;rotationAnimation.removedOnCompletion = NO;rotationAnimation.fillMode = kCAFillModeForwards;rotationAnimation.timingFunction =    [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];rotationAnimation.duration = 10.0;CALayer *layer = [viewToSpin layer];[layer addAnimation:rotationAnimation forKey:@"rotationAnimation"];

You can control the duration of the total animation with the rotationAnimation.duration property, and the acceleration and deceleration (and calculation of steps in between) with the rotationAnimation.timingFunction property.

Getting a continuous spinning effect is a little tricky, but I describe a means to do it here. Yes, Core Animation seems to optimize transforms to the closest ending position within the unit circle. The method I describe there chains a few half-rotation animations together to make full rotations, although you do notice a slight stutter in the handoff from one animation to the next.

Perhaps a CAKeyframeAnimation constructed with these half-rotation values would be the right way to go. Then you could also control acceleration and deceleration.