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iOS Object-Oriented Swift 2.0 Class Inheritance Creating a Subclass

Davis Meissner
Davis Meissner
1,179 Points
Posted by Davis Meissner
Davis Meissner
1,179 Points

It is telling me numberOfSeats not initialized in super.init but when i add it it tells me i have an extra argument

So like I said in the title.... I am stumped.

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


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

class Car: Vehicle {
    let isCar: Bool = true
    var numberOfSeats: Int

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

2 Answers

Steven Deutsch
Steven Deutsch
21,046 Points
Steven Deutsch
Steven Deutsch
21,046 Points

Hey Dave Meissner,

The challenge wants you to create a new property in your Car subclass, numberOfSeats, with a default value of 4. Because it is a default value, you don't need to initialize it. Therefore, you don't have to pass another parameter into the initializer.

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 = 4

    override init(withDoors doors: Int, andWheels wheels: Int) {
        super.init(withDoors: doors, andWheels: wheels)
    }
}

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

Note: You don't even need an initializer for this subclass because you will automatically use the initializer of the parent class since no new properties need to be initialized. 

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 = 4

}

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

Hope this helps! Good Luck!