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iOS Object-Oriented Swift Value vs Reference Types Final Challenge

Paul Denlinger
Paul Denlinger
2,380 Points

Where to set default for wheels, doors?

Not quite sure about where to set the default for the wheels, doors. Help!

Vehicle.swift
class Vehicle {
    let wheels: Int
    let doors: Int

    // Designated initializer
    init(wheels:Int, doors:Int){
      self.wheels = wheels
      self.doors = doors

    }
}

class Car: Vehicle {
    // A car must default to 4 wheels and 4 doors
    var auto = Car(wheels = 4, doors = 4)
    init(){
      // call super.init
      super.init()
    }
}

1 Answer

Jhoan Arango
Jhoan Arango
14,575 Points

Hey Paul, you are creating an instance of car inside the class. First delete the “var auto” instance, and then on the super.init() add the default values. It should look something like this.

super.init(wheels: 4, doors: 4)

remember, with the super.init you are calling the initializer from the super class “Vehicle”. All you are doing now is adding default values to it. Please let me know if it helps.

Paul Denlinger
Paul Denlinger
2,380 Points

Thank you for the input; that worked.

I need to practice this more in order to get better, but I think that I get the general idea.

Thanks again!

Jhoan Arango
Jhoan Arango
14,575 Points

No problem... That’s what I try to do everyday, practice and practice. It’s the only way to get better.