iOS Swift 3 Architecture issue

Question

I'm trying to find the best solution for a recurrent problem I have, which I solved differently each time.

Imagine I have a form in several steps ( let say 2 to begin )

My code structure is :

class SuperStepViewController: UIViewController {

  //Some generic Stuff

    func continueAction(sender : AnyObject?) {
        //NOTHING
    }
}


class Step1ViewController: SuperStepViewController { 

    override func continueAction(sender : AnyObject?) {
        //DO SOME USEFULL STUFF
    }

}


class Step2ViewController: SuperStepViewController { 

    override func continueAction(sender : AnyObject?) {
        //DO SOME USEFULL STUFF
    }

}

What I want is to change this code, to not implement the continueAction function in the SuperViewController , because it has no default implementation.

At a first look, I thought protocol was a good idea. If I put continueAction in a required protocol, I will have a compilation-time error, which is what I want.

protocol StepProtocol {
    func continueAction()
} 

class SuperStepViewController: UIViewController {
    //GENERIC
}


class Step1ViewController: SuperStepViewController, StepProtocol { 

   func continueAction(sender : AnyObject?) {
        //DO SOME USEFULL STUFF
    }

}


class Step2ViewController: SuperStepViewController, StepProtocol { 

   func continueAction(sender : AnyObject?) {
        //DO SOME USEFULL STUFF
    }

}

But it is not enough, I want generate this compilation as soon as I subclass the superview controller. I know Java as something like Abstract class.

class Step3ViewController: SuperStepViewController { 

   //NO continueAction implementation => No compilation error

}

Did anyone have an idea ?

Answer 1

No. This is not possible in Swift. Swift does not support such activity.