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

Lana Wong
Lana Wong
3,968 Points

How do you do this? I forgot how to deal with coordinates and switch statements, etc.

Hi, Can someone help me solve this. It has been a while since I did this stuff, and I need to be caught up again. Thank you so much. :)

Instructions: In the editor you've been provided with two classes - Point to represent a coordinate point and Machine. The machine has a move method that doesn't do anything because most machines are motionless.

Your task is to subclass Machine and create a new class named Robot. In the Robot class, override the move method and provide the following implementation. If you enter the string "Up" the y coordinate of the Robot's location increases by 1. "Down" decreases it by 1. If you enter "Left", the x coordinate of the location property decreases by 1 while "Right" increases it by 1.

Note: If you use a switch statement you can use the break statement in the default clause to exit the current iteration.

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! Im a machine!")
    }
}

// Enter your code below
let Robot: Machine {
override func move(direction: String){

}
}

3 Answers

John Roque Jorillo
John Roque Jorillo
13,117 Points

class Robot: Machine { 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 } } }

Your task is to subclass Machine and create a new class named Robot

  • You should create class rather than a constant

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

class Robot: Machine { 
  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 
} 
} 
}