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

isaac brakha
isaac brakha
6,781 Points

What should i do different

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

class Robot: Machine {

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


   }
  }

}

1 Answer

Reed Carson
Reed Carson
8,306 Points

You need to switch on the parameter "direction", not the function "move" itself.

The function takes in a string value and you are calling the switch on that value, executing different code based on different strings passed in.