How to get this value as a CGFloat?

Question

I am asking for an Value like this:

[self.layer valueForKeyPath:@"transform.rotation.z"]

bit I need to pass it to a method which takes a CGFloat as parameter. What's the casting trick here?

Answer 1

In Swift:

let f = view.layer.valueForKeyPath("transform.rotation.z")!.floatValue

In Objective-C:

NSNumber* n = [self.layer valueForKeyPath:@"transform.rotation.z"];
CGFloat f = [n floatValue];