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

Posted by Jacob Asher
Jacob Asher
1,174 Points

I need help with this code challenge

class Point { var x: Int var y: Int

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

}

enum Direction { case Left case Right case Up case Down }

class Machine { var location: Point

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

func move(direction: String) {
    print("Do nothing! Im a machine!")
}

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

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

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

2 Answers

Jeff McDivitt
Jeff McDivitt
23,970 Points
Jeff McDivitt
Jeff McDivitt
23,970 Points

Close but you don't need the initializer also the right is increasing by 1 and the left is decreasing by one

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 += 1
    case "Down":
        self.location.y -= 1
    case "Right":
        self.location.x += 1
    case "Left":
        self.location.x -= 1
    default:
        break
    }
}

}
Jeff McDivitt
Jeff McDivitt
23,970 Points
Jeff McDivitt
Jeff McDivitt
23,970 Points

You need to create the class Robot that inherits from machine, you also need to override the function using the override keyword

Jacob Asher
Jacob Asher
1,174 Points

like this? 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
    }
}

}