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iOS Object-Oriented Swift 2.0 Class Inheritance Creating a Subclass

Ryan Maneo
Ryan Maneo
4,342 Points

Ugh

Missing parameter for "andWheels" even though I put a parameter... help?

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 = 4



}
let someCar = Vehicle(withDoors: 2, andWheels: 4, Car(numberOfSeats: 4))

1 Answer

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 = 4

}

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

You have:

let someCar = Vehicle(withDoors: 2, andWheels: 4, Car(numberOfSeats: 4))

First, you were supposed to make someCar a Car, not a Vehicle. Second, you can't pass a 3rd parameter, because the init inherited from Vehicle only accepts two parameters: withDoors and andWheels. Third, you don't need to pass in the number of seats because the number is hardcoded in the Car class.