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iOS Object-Oriented Swift Value vs Reference Types Final Challenge

Austin Wyatt
Austin Wyatt
3,146 Points

Im not sure how to correct the error for this coding challenge

I needed to correct the code for this challenge. I did as much as I could and I can't figure out what I am missing. Im not sure what properties I would add for the "Car" subclass, and when I click preview, it doesn't say I'm missing any.

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
    init(){
      super.init(wheels: wheels, doors: doors)// call super.init
    }
}

1 Answer

You haven't actually specified what values to use in your Initializer:

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
    init(){
      // call super.init
      super.init(wheels:4, doors:4)
    }
}

(Basically, you said "use the wheels value for how many wheels the car has" (and same for doors), but never told it what the default value was in the first place)