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iOS Object-Oriented Swift Class Inheritance Creating a Subclass

Margarita Garmutė
Margarita Garmutė
2,136 Points

Can anyone help me with subclassing and inherence.

Can't understand what's wrong.

Thanks for help.

objects.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 = 4

     convenience init(withDoors doors: Int, andWheels wheels: Int, withSeats seats: Int) {

        self.init(withDoors: 5, andWheels: 4, withSeats: 4)
        self.numberOfSeats = seats
       }

}

let someCar = Car(withDoors: 5, andWheels: 4, withSeats: 4)

2 Answers

Jeff McDivitt
Jeff McDivitt
23,970 Points

You are not a need for the initialization in the Car class, the below is what the task is asking for:

class Vehicle {
    var numberOfDoors: Int
    var numberOfWheels: Int

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

class Car: Vehicle {

    var numberOfSeats: Int = 4
}

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

However if you did need to override the initialization you would do it like below

class Vehicle {
    var numberOfDoors: Int
    var numberOfWheels: Int

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

class Car: Vehicle {

    var numberOfSeats: Int

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

    }
}

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