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

Drew Hartsfield
Drew Hartsfield
2,212 Points
Posted by Drew Hartsfield
Drew Hartsfield
2,212 Points

Need Help!!

Directions::::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.

//Not sure what to do, need some help

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 class Robot: Machine { override func move(var direction: String) { if direction = "Up" { location.y } } }

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

1 Answer

Andres Aguero
Andres Aguero
30,545 Points
Andres Aguero
Andres Aguero
30,545 Points

Hey Drew,

You should be able to complete the challenge using a switch statement. When someone types in the word "Up" into the direction parameter, the y point should move +1. When someone types the word "Down" into the direction parameter then y should move -1.

class Robot: Machine {
    override func move(direction: String) {
        switch direction {
        case "Up":
            self.location = (Point(x: 0, y: 1))
        case "Down":
            self.location = (Point(x: 0, y: -1))
        case "Left":
            self.location = (Point(x: -1, y: 0))
        case "Right":
            self.location = (Point(x: 1, y: 0))
        default: break
        }
    }
}