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iOS Build a Simple iPhone App with Swift Getting Started with iOS Development Swift Recap Part 2

Not sure how to complete exercise.

Hi, I'm not sure why I'm receiving an error with the exercise. Here is my code:

class Point { var x: Int var y: Int

init(x: Int, y: Int) {
    self.x = x
    self.y = y
}

}

class Machine { var location: Point

init() {
    self.location = Point(x: 0, y: 0)
}

func move(_ direction: String) {
    print("Do nothing! I'm a machine!")
}

}

class Robot: Machine {

override init() {



    func move(_ direction: String) {

        switch direction {
        case "Up": location.y += 1
        case "Down": location.y -= 1
        case "Left": location.x -= 1
        case "Right": location.x += 1
        default: break }

    }

}

}

Any help would be greatly appreciated!

Thanks, Ben

robots.swift
class Point {
    var x: Int
    var y: Int

    init(x: Int, y: Int) {
        self.x = x
        self.y = y
    }
}

class Machine {
    var location: Point

    init() {
        self.location = Point(x: 0, y: 0)
    }

    func move(_ direction: String) {
        print("Do nothing! I'm a machine!")
    }
}

class Robot: Machine {

    override init() {



        func move(_ direction: String) {

            switch direction {
            case "Up": location.y += 1
            case "Down": location.y -= 1
            case "Left": location.x -= 1
            case "Right": location.x += 1
            default: break }

        }

 }

}

1 Answer

Jeff McDivitt
Jeff McDivitt
23,970 Points

Hi Benjamin - The problem is your Robot class; here is how it should look; you are overriding the functions incorrectly

class Robot: Machine {

    override func move(_ direction: String) {
        switch direction {
        case "Up":
            location.y += 1
        case "Down":
            location.y -= 1
        case "Left":
            location.x -= 1
        case "Right":
            location.x += 1
        default:
            break
        }
    }
}