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

Posted by Ray Hiera
Ray Hiera
1,870 Points

use of unresolved identifier x , y

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 {

let isRobot: Bool = true

override func move (direction: String) {

switch direction { case "Up": y++ case "Down": y-- case "Left": x-- case "Right": x++ default: break

} } }

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 {

let isRobot: Bool = true

override func move (direction: String) {

switch direction {
case "Up":
y++
case "Down":
y--
case "Left":
x--
case "Right":
x++
default:
break

   }
  }
 }

2 Answers

Sid b
Sid b
15,346 Points

In your switch statement, you need to call x, y on your location variable and assign a new value.

Ray Hiera
Ray Hiera
1,870 Points

Thanks Sid for your help.

Reed Carson
Reed Carson
8,306 Points
Reed Carson
Reed Carson
8,306 Points

it doesnt know what x and y are. Those are properties of your location variable so you need to access it that way

Ray Hiera
Ray Hiera
1,870 Points

Thank you for your help Reed. It helped me to solve the problem