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

William Hartvedt Skogstad
William Hartvedt Skogstad
5,857 Points

Need help with the switch statement

Challenge Task 1 of 1

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! I`m a machine!")
    }
}

// Enter your code below

class Robot: Machine {
    override func move(direction: String) {
        switch move {
            case "Up":

            case "Down":

            case "Left":

            case "Right":

        default: break
        }
    }
}

3 Answers

Keli'i Martin
Keli'i Martin
8,227 Points

You should be switching on direction, not move. Trying making that change and see if it works.

William Hartvedt Skogstad
William Hartvedt Skogstad
5,857 Points

Thanks for clearing that part! But i still need help with what to type in for the cases..

Keli'i Martin
Keli'i Martin
8,227 Points

Inside each of the case statements, you should just be incrementing or decrementing one of the points, depending on the requirements. So, for example, in the case of "Up", you'd have:

case "Up":
  self.location.y++

Hope that helps!

William Hartvedt Skogstad
William Hartvedt Skogstad
5,857 Points

Thanks! I was in on it but it didn't work before when i switched on move instead of direction. Now i fully understand things :)

Keli'i Martin
Keli'i Martin
8,227 Points

Fantastic! Glad to be of assistance.

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