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

Saleh Bubishate
Saleh Bubishate
1,613 Points

it's really confusing task

I have a problem with re-defining the initializer method. then how to re-define the move method?

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 am a machine!")
    }
}

class Robot : Machine {

    override init() {

    super.init()

    }
        override func move(_ direction: String) {
            switch direction {
            case "up" : location = Point( x = x , y += y)
            case "down" : location = Point( x = x , y -= y)
            case "right" : location = Point( x += x , y = y)
            case "left" : location = Point( x -= x , y = y)
            default: break
            }
            }
}



let robot1 = Robot

1 Answer

Magnus Hållberg
Magnus Hållberg
17,232 Points

You are almost there, you can use dot notation on location to access the value you want to alter inside the switch statement. So the override method should look like this:

class Robot: Machine {
    override init() {
    super.init()
  }

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