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iOS Object-Oriented Swift 2.0 Class Inheritance Creating a Subclass

Tyron Spencer
Tyron Spencer
1,489 Points
Posted by Tyron Spencer
Tyron Spencer
1,489 Points

Please help. Stuck on class inheritance

Hi everyone, could somebody please help me out here. Im slowly getting the hang of classes but really stuck on this one. So confusing

The task is to create a subclass of Vehicle, named Car, that adds an additional stored property numberOfSeats of type Int with a default value of 4.

Once you've implemented the Car class, create an instance and assign it to a constant named someCar.

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 = 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)
Andrew Taylor
Andrew Taylor
11,500 Points

What's the question?

4 Answers

Andrew Taylor
Andrew Taylor
11,500 Points

Try this 

class Car: Vehicle {
  var numberOfSeats: Int 

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

let someCar = Car(withDoors: 4, andWheels: 4)
Tyron Spencer
Tyron Spencer
1,489 Points
Tyron Spencer
Tyron Spencer
1,489 Points

Thanks Andrew, worked perfectly. Cheers

Tyron Spencer
Tyron Spencer
1,489 Points
Tyron Spencer
Tyron Spencer
1,489 Points

sorry i will check again, and post the question to my code Cheers

.... Ok so, here is what the question was asking:

In the editor, I have provided a class named Vehicle.

Your task is to create a subclass of Vehicle, named Car, that adds an additional stored property numberOfSeats of type Int with a default value of 4.

Once you've implemented the Car class, create an instance and assign it to a constant named someCar.

Sathya vegunta
Sathya vegunta
4,061 Points
Sathya vegunta
Sathya vegunta
4,061 Points

Hi,

The task is to create a subclass and then create an instance of the subclass and assign it to the constant someCar.

Creating a Subclass:

class Car:Vehicle { var numberOfSeats: Int=4 // default value of 4 is assigned to the variable numberOfSeats }

//creating an instance and assigning it to constant let someCar=Car(withDoors:4, andWheels:4)

Tyron Spencer
Tyron Spencer
1,489 Points
Tyron Spencer
Tyron Spencer
1,489 Points

Thanks Andrew worked perfectly.. Cheers