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iOS

Sam Belcher
Sam Belcher
3,719 Points
Posted by Sam Belcher
Sam Belcher
3,719 Points

super init and class inheritance

I am really confused with super inits and when to override an init value. I understand how to make a class but basically I am stuck on inheritance

3 Answers

Jeff McDivitt
Jeff McDivitt
23,970 Points
Jeff McDivitt
Jeff McDivitt
23,970 Points

Hi Sam -

You state that you know how to make a class so I assume that you are ok with initialization as well. If not let me know, but anyway on the inheritance.

Let's say we have a class 

class Machine {

    var id: Int
    var name: String
    var automaticallyRuns: Bool

    init(id: Int, name: String, automaticallyRuns: Bool) {
        self.id = id
        self.name = name
        self.automaticallyRuns = automaticallyRuns
    }

}

Now lets say we have another class that inherits from Machine

class SuperMachine: Machine {

    var partsMade: String

    init(id: Int, name: String, automaticallyRuns: Bool,partsMade: String) {
        self.partsMade = partsMade
        super.init(id: id, name: name, automaticallyRuns: automaticallyRuns)
    }

}

We added something to the second class var partsMade: String, but the second class also inherits everything from its parent class (see below)

var myMachine = Machine(id: 1, name: "My Machine", automaticallyRuns: false)
var mySuperMachine = SuperMachine(id: 2, name: "My Super Machine", automaticallyRuns: true, partsMade: "Metal")
Sam Belcher
Sam Belcher
3,719 Points
Sam Belcher
Sam Belcher
3,719 Points

thanks! but I am still a little confused with the function of the super init, and I don't understand why the variables of the super init have the same type as their name. Also, when do you override an init? and when do you write additional code under the super init?

Jeff McDivitt
Jeff McDivitt
23,970 Points
Jeff McDivitt
Jeff McDivitt
23,970 Points

Hi Sam -

This tutorial is probably the best way I have seen it explained. If you still have questions let me know