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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 Unsubscribed User
Unsubscribed User
12,874 Points

Subclass Machine and create a new class called Robot

Trying to complete the final Challenge Task where I need to use a switch statement to change the location property of the Robot from the subclass method.

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

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
}


}

}

3 Answers

Ben Shockley
Ben Shockley
6,094 Points
Ben Shockley
Ben Shockley
6,094 Points

You've got this pretty much dead on right, you just missed one thing, from what I can tell.

You need to set the coordinate of each movement equal to an increment or decrement. So instead of just saying 

case "Up": location.y + 1

You need to say 

case "Up": location.y += 1

otherwise it won't actually store that increment once the switch statement exits. When I made this change, it passed the challenge with no issues.

-- Ben

Unsubscribed User
Unsubscribed User
12,874 Points
Unsubscribed User
Unsubscribed User
12,874 Points

Thank you very much Ben, this works perfectly now!

Pavel Bogart
Pavel Bogart
1,713 Points
Pavel Bogart
Pavel Bogart
1,713 Points

an option using switch:

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
        }
    }

}