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iOS Object-Oriented Swift 2.0 Class Inheritance Creating a Subclass

Your definition of Car needs to contain the property specified in the directions

what about this one?

class Vehicle {
    var numberOfDoors: Int
    var numberOfWheels: Int
    var numberOfSeats: Int

    init(withDoors doors: Int, andWheels wheels: Int, withSeats seats: Int) {
        self.numberOfDoors = doors
        self.numberOfWheels = wheels
        self.numberOfSeats = seats

class Car: Vehicle {
    override init(withDoors doors:Int,andWheels wheels:Int,withSeats seats:Int) {
    self.numberOfSeats = 4

let someCar = Car(withDoors:0, andWheels: 0, withSeats: 0)

2 Answers

Hi there!

You've got a couple of bits that need changing here.

First, put the Vehicle class back to how it was at the start; don't change Vehicle, that's your superclass that you want to inherit from. Next, create a subclass called Car that inherits from Vehicle:

class Car : Vehicle {}

In that class, define a member variable called numberOfSeats and make that an Int datatype. Next up, override the init method. Here, pass in the two parameters required for the super which are withDoors and andWheels. Inside, assign the value of 4 to numberOfSeats - you want a default value for the challenge. Then, call super.init as normal. Last. create an instance and store it in someCar. You end up with:

class Car : Vehicle {
  var numberOfSeats: Int
  override init(withDoors doors: Int, andWheels wheels: Int) {
    self.numberOfSeats = 4
    super.init(withDoors: doors, andWheels: wheels)

let someCar = Car(withDoors: 4, andWheels: 4)

I hope that helps,


thks Bud

No problem! :+1: