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iOS Build a Simple iPhone App with Swift 2.0 Getting Started with iOS Development Swift Recap Part 2

Swift Recap Part 2

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 { init(x: Int, y: Int) { }

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

}

let robot = Robot(x: 0, y: 0) robot.location robot.move("Down") robot.location

classes.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!")
    }
}

// Enter your code below
class Robot : Machine {
    init(x: Int, y: Int) {
    }

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

Hi, I'm stuck in this part of the swift recap part 2. Could you please take a look at my code, and help me out? It won't pass the test. :) Thanks!.

1 Answer

Paul Brazell
Paul Brazell
14,371 Points

Your left and right cases are backwards. If you are moving to the right, you would be adding to the x value. If you are going to the left, you would decrease x. Here is the solution:

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