ObjC protocol Implementation in Swift

Question

Ok here is the big problem. I had a library written in ObjC(this). There we had a defined protocol. When I tried to use it in swift file I get constantly:

Answer 1

I don't know if this is a bug or not. The Objective-C protocol method

- (NSString *)getAxisLabel:(id)axis Value:(CGFloat)value;

(with uppercase "V" in Value:) is mapped to Swift as

func getAxisLabel(axis: AnyObject!, value: CGFloat) -> String!

(with lowercase "v" in value:), but none of

func getAxisLabel(axis: AnyObject!, value: CGFloat) -> String! { }
func getAxisLabel(axis: AnyObject!, Value: CGFloat) -> String! { }

is accepted by the compiler to satisfy the protocol requirement.

As a workaround, you can annotate the method with an explicit Objective-C selector name:

class ViewController: UIViewController, MyProtocol
{
    @objc(getAxisLabel:Value:)
    func getAxisLabel(axis: AnyObject!, value: CGFloat) -> String! {
        return ""
    }
}