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iOS Object-Oriented Swift 2.0 Class Inheritance Overriding Methods

Posted by Allison Larson
Allison Larson
3,177 Points

I've provided a base class Person in the editor below. Once an instance of Person is created, you can call getFullName()

I've provided a base class Person in the editor below. Once an instance of Person is created, you can call getFullName() and get a person's full name.

Your job is to create a class named Doctor that overrides the getFullName() method. Once you have a class definition, create an instance and assign it to a constant named someDoctor.

For example, given the first name "Sam", and last name "Smith", calling getFullName() on an instance of Person would return "Sam Smith", but calling the same method on an instance of Doctor would return "Dr. Smith".

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:Person {
    override init(firstName: String, lastName: String) {
        super.init(firstName: "John", lastName: "Smith")
    }

    override func getFullName() -> String {
        return "Dr. \(lastName)"
    }
}

let smith = Person(firstName: "John", lastName: "Smith")
smith.getFullName()

let john = Doctor(firstName: "John", lastName: "Smith")
john.getFullName()

1 Answer

Gavin Maxwell
Gavin Maxwell
3,521 Points
Gavin Maxwell
Gavin Maxwell
3,521 Points

Almost there... you need to make sure your doctor is called someDoctor, and then also ensure the init method is calling the parent init method correctly. This should help:

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:Person {
    override init(firstName: String, lastName: String) {
        super.init(firstName: firstName, lastName: lastName)
    }

    override func getFullName() -> String {
        return "Dr. \(lastName)"
    }
}

let smith = Person(firstName: "John", lastName: "Smith")
smith.getFullName()

let someDoctor = Doctor(firstName: "John", lastName: "Smith")
someDoctor.getFullName()
Unsubscribed User
Unsubscribed User
Courses Plus Student 2,114 Points

It says override getfullname() so why did you override init.