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

I dont know what is wrong

class Robot: Machine{ override init(x: Int, y: Int) { super.init(x: x, y: y) } override func move(_ direction: String) { switch(direction){ case "Up": self.y+=1 case "Down": self.y-=1 case "Left": self.x-=1 case "Right":self.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!")
  }
}

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

}

1 Answer

Charles Kenney
Charles Kenney
15,604 Points

At least for the challenge you linked, you do not have to modify the parent init method. You only need to override the move method. You should be changing the x/y values of the inherited property 'location' (self.location.x/self.location.y), as there are no self.x or self.y properties with Robot. This is what your object should look like:

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
    }
  }
}

Hope this helps,

Charles