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iOS Object-Oriented Swift 2.0 Class Inheritance Overriding Methods

Piers FC
Piers FC
10,402 Points
Posted by Piers FC
Piers FC
10,402 Points

Object-Orientated Swift 2.0 - Inheritance - last task

I am on the last task of the inheritance section in Swift Object-Orientated Swift 2.0 and I have no idea why my code isn't working.

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

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

let someDoctor = Docter(firstName: "piers", lastName: "Ebdon")
someDoctor.getFullName

I am getting the error of I need to declare a doctor class, yet I clearly am. It is really irritating that their is no way to see the answer if you are really stuck and can't get help from anyone.

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

3 Answers

Steve Hunter
Steve Hunter
57,712 Points
Steve Hunter
Steve Hunter
57,712 Points

Hi Piers,

You don't need to override the init method - that stays the same.

The only override is the getFullName() method and you've done that right.

Also, I don't now how picky the compiler is but it wouldn't surprise me if spelling Doctor wrong has upset it. Maybe correct that too. [EDIT] - Just checked, yes, it wants a class named Doctor.

Lastly, you call the method with brackets:

someDoctor.getFullName() // brackets added

Let me know how you get on.

Steve.

Steve Hunter
Steve Hunter
57,712 Points

Your final code:

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

let someDoctor = Doctor(firstName: "Steve", lastName: "Hunter")
someDoctor.getFullName()
Piers FC
Piers FC
10,402 Points
Piers FC
Piers FC
10,402 Points

Hi Steve thanks for helping out.

The final code worked :).

However, I don't fully get why you didn't need to initialize the first part of the class statement. Is it because you inherit the initialisers from the Person class and so if you are not changing them then you do not need to include them?

I thought from the videos that regardless of if you are changing anything or not, you still need to initialise all properties in the superclass. Is that not the case?

Cheers Piers

Steve Hunter
Steve Hunter
57,712 Points
Steve Hunter
Steve Hunter
57,712 Points

Hi Piers,

I believe you are correct, yes. The initializer is inherited if not overridden. An override must include a change; something different must happen. You can, indeed you probably should call the super init if relevant, in such scenarios.

I hope that helps!

Steve.