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iOS Object-Oriented Swift 2.0 Class Inheritance Overriding Methods

Posted by Andrew Sherman
Andrew Sherman
6,799 Points

Can't figure out what it wants me to do to get this to pass.

title. I found this confusing and can't seem to see what I'm missing here.

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: firstName, lastName: lastName)
        self.firstName = "Dr"
    }
}

let someDoctor = Doctor(firstName: "Dr", lastName: "Smith")

2 Answers

Sonia Feldman
Sonia Feldman
3,873 Points

Hi Andrew!

Your solution doesn't quite do what the challenge requests. Your code currently treats "Dr." as an instance of firstName, but the challenge wants you to change the parent class to either include a new parameter, or edit the return value.

There are two solutions that work. The simplest solution is to override the getFullName function. That looks like this. 

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)"
    }

class Doctor: Person {

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

}

let someDoctor = Doctor(firstName: "Sam", lastName: "Smith")

someDoctor.getFullName()

Another option is to introduce a new parameter with a default value of "Dr." This method is the more flexible of the two options, as you could feasibly change the default profession if you wanted to. 

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 {

    var profession: String = "Dr."

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

}

let someDoctor = Doctor(firstName: "Sonia", lastName: "Feldman")

someDoctor.getFullName()
jcorum
jcorum
71,830 Points
jcorum
jcorum
71,830 Points

Andrew, basically it wants you to override the function, not the initializer:

class Doctor: Person {

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

let someDoctor = Doctor(firstName: "Sam", lastName: "Smith")

Also, you don'l call the Doctor initializer with a first name of "Dr.", that is provided by the overridden function.