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

David Palomar
David Palomar
7,303 Points

Robots.swift not works?

// Enter your code below class Robot: Machine { override func move(direction: String) { switch direction { case "Up": self.location.y += 1 print("hola") case "Down": self.location.y -= 1 case "Left": self.location.x -= 1 case "Right": self.location.x += 1 default: break } } } let rob = Robot() rob.move(direction: "Up") print(rob.location.x)

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! Im a machine!")
  }
}

// Enter your code below
class Robot: Machine {
  override func move(direction: String) {
    switch direction {
      case "Up":
        self.location.y += 1
        print("hola")
      case "Down":
        self.location.y -= 1
      case "Left":
        self.location.x -= 1
      case "Right":
        self.location.x += 1
      default: break
    }
  }
}
let rob = Robot()
rob.move(direction: "Up")
print(rob.location.x)

1 Answer

Hi David,

If you add the underscore in the overridden move method, your code will pass the challenge:

// Enter your code below
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
    }
  }
}

Steve.