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iOS Object-Oriented Swift Class Inheritance Creating a Subclass

nader adam
PRO
nader adam
Pro Student 548 Points

what can i do here

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

}

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

}

1 Answer

Robert Clayton
Robert Clayton
5,331 Points

You need to add a new init.

Declare which init you will override, which is the Vehicles init: init(withDoors doors: Int, andWheels wheels: Int).

Then add the new value to the subclasses init: self.numberOfSeats = 4

Finally declare the new (super)init: (withDoors: doors, andWheels: wheels)

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

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