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iOS Object-Oriented Swift 2.0 Class Inheritance Overriding Methods

Davis Meissner
Davis Meissner
1,179 Points

I forgot how to make a subclass to Person

How do I make Doctor a subclass of person?

classes.swift
class Person {
    let firstName: String
    let lastName: String

    init(firstName: String, lastName: String) {
        self.firstName = firstName
        self.lastName = lastName
    }

    func getFullName() -> String {
        return "\(firstName) \(lastName)"
    }
}

// Enter your code below
class Doctor{
    let firstName: String
    let lastName: String

    init (firstName: String, lastName: String) {
    self.firstName = firstName
    self.lastName = lastName
    }

    func getFullName() -> String {
      return "Dr. \(lastName)"
    }
}
let someDoctor = Doctor(firstName: "Sam", lastName: "Smith")

1 Answer

Davis, you did too much, in a couple of places and left out a couple of things, but you're on the right track. You don't need to duplicate the stored properties -- they are inherited. You don't need an initializer as that's inherited. You do need to say that Doctor is a subclass of Person (Doctor: Person), and you do need to use the override keyword on the function:

class Doctor: Person{

    override func getFullName() -> String {
      return "Dr. \(lastName)"
    }
}
let someDoctor = Doctor(firstName: "Sam", lastName: "Smith")