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iOS Object-Oriented Swift Value vs Reference Types Final Challenge

Austin Wyatt
Austin Wyatt
3,146 Points
Posted by 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

Hao Tran
Hao Tran
16,610 Points
Hao Tran
Hao Tran
16,610 Points

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)