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

Can not get past robots.swift, need help

We as a class can not get past this point. We have tried many options. Please help.

robots.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

1 Answer

David Papandrew
David Papandrew
8,386 Points

Hi Jarrett,

In this challenge, you need to create a new class, Robot, that is a subclass of Machine.

All the subclass needs to contain is a method called "move" that overrides the superclass method of the same name.

The move method takes an argument, direction. We will use the value from this argument to move the location (x or y coordinate) which is a class property defined in the Machine superclass.

Here is the code:

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