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iOS Object-Oriented Swift Class Inheritance Creating a Subclass

Johnny Nguyen
Johnny Nguyen
3,875 Points
Posted by Johnny Nguyen
Johnny Nguyen
3,875 Points

I don't what to do with this challenge

I don't even know what is his task about.

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
}

let someCar = Car()

1 Answer

Lucian Rotari
Lucian Rotari
12,007 Points
Lucian Rotari
Lucian Rotari
12,007 Points

I am not sure if I am right but it worked for me (I didn't reach that lvl yet but I did this chalenge just now).

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

Just have a look at this pice of code. You have created a subclass of Vehicle that means when you create an instance of subclass Car you have to provide the arguments for parameters "withDoors", "andWheels".

So my solution is 

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 = Car(withDoors: 4, andWheels: 4)

It works but I am not sure is the right way

Johnny Nguyen
Johnny Nguyen
3,875 Points
Johnny Nguyen
Johnny Nguyen
3,875 Points

It doesn't work for me