How to call super convenience init

Question

Created Jun ’15

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How can I call convenience initializer from superclass? When I try to call it in "old" and "logical" way it thorws error: "Must call a designated initializer of the superclass <SuperClassName>"

Here's some code:

Framework class

class UIAlertView : UIView {

    convenience init(title: String?, message: String?, delegate: AnyObject?, cancelButtonTitle: String?) /<UIAlertViewDelegate>*/

    init(frame: CGRect)
    init(coder aDecoder: NSCoder)
}

My class (edit: I've forgotten other initializers)

class ConfirmationAlert: UIAlertView, UIAlertViewDelegate {


    init(title: String?, message: String?, cancelButtonTitle: String? = "common_cancel") {
        super.init(title: title, message: message, delegate: nil, cancelButtonTitle: cancelButtonTitle)  //error here
        delegate = self
    }

    override init(frame: CGRect) {
        super.init(frame: frame)
    }
    required init(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
    }
}

The point is: when calling convenience initializer from superclass, it still has to call own designated constructor. So what's the point in disallowing it?

How can I bypass this and call the initializer I wanted to call in the first place?

edit:

I don't know which designated initializer to call, moreover with what parameters? I just want to call a super convenience initializer because it knows which super designated initializer to call.

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Answer 1

marchyman OP

Jun ’15

I think if you add the following (haven't tested, but the playground is happy)

    required init(coder: NSCoder) {
        super.init(coder: coder)
    }

to class ConfirmationAlert you can call the super initializer you wish to call.

0

Answer 2

rafal OP

Jun ’15

Thanks @marchyman for your answer. I've mistakenly pasted too small fragment of my code. Already edited original post and added missing initializers.

Despite having all this initializers, I still cannot make this code work - in swift 1.2 it worked seamlessly.

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