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iOS Object-Oriented Swift 2.0 Class Inheritance Creating a Subclass

The code is not working. Can u give some advice, please?

class Vehicle { var numberOfDoors: Int var numberOfWheels: Int

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

}

// Enter your code below class Car: Vehicle { var numberOfSeats: Int

init(numberOfSeats: Int, doors: Int, wheels: Int) { self.numberOfSeats = numberOfSeats super.init(numberOfDoors: doors, numberOfWheels: wheels) } }

let someCar = Car(numberOfSeats: 4, doors: 10, wheels: 7)

classes.swift
class Vehicle {
    var numberOfDoors: Int
    var numberOfWheels: Int

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

// Enter your code below
class Car: Vehicle {
  var numberOfSeats: Int

  init(numberOfSeats: Int, doors: Int, wheels: Int) {
    self.numberOfSeats = numberOfSeats
    super.init(numberOfDoors: doors, numberOfWheels: wheels)
  }
}

let someCar = Car(numberOfSeats: 4, doors: 10, wheels: 7)

1 Answer

jon kelson
jon kelson
5,149 Points

class Vehicle { let wheels: Int let doors: Int

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

}

}

class Car: Vehicle { var seat: Int

// A car must default to 4 wheels and 4 doors
init(wheels: Int, doors: Int, seat: Int){
    self.seat = seat
    super.init(wheels: 4, doors: 4)

}

convenience init(seat: Int) {
    self.init(wheels: 4, doors: 4, seat: 2)
}

}

let someCar = Car(wheels: 4, doors: 4, seat: 4)