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

Posted by diegoarenas
diegoarenas
21,753 Points

I dont get why my code is not working

I tried everything and its not working

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!")
  }
}

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

1 Answer

doesitmatter
doesitmatter
12,885 Points
doesitmatter
doesitmatter
12,885 Points

Read the error. It says that there is a compile error and to click preview. If you did do that. You would see whats wrong with your code, namely two things:

  1. ++ isn't supported in swift 3
  2. when you override a method you must have the exact same parameters so: _ direction : String and not just direction : String
// 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
        }
    }
}