Protocols in Swift 3

Question

I have looked at others code and nothing seems to work. Here is the challenge:

In the editor below, I've declared a class, WifiLamp, that represents an interface to one of those Internet of Things lamps. The class models state that determines whether the lamp is on or off and a color, represented by the Color enum. For the first step, declare a protocol named ColorSwitchable. The protocol has a single requirement: a method named switchColor that takes a value of Color as an argument. For the sake of this challenge, make sure your external argument label is omitted by using an underscore. Give the argument a local name of color.

protocols.swift

// Declare protocol here
protocol ColorSwitchable {    // declared protocol
func switchColor(_ color: Color) {
  } // method with ommitted external label and color as the internal label
}

enum LightState {
  case On, Off
}

enum Color {
  case RGB(Double, Double, Double, Double)
  case HSB(Double, Double, Double, Double)
}

class WifiLamp {
  let state: LightState
  var color: Color

  init() {
    self.state = .On
    self.color = .RGB(0,0,0,0)
  }
  func switchColor(_ : Color)
}

Answer 1 · 2017-01-16T20:30:32Z

January 16, 2017 8:30pm

Hey Matt Baldwin,

Try removing the curly braces from the switchColor declaration in the ColorSwitchable protocol.

// Declare protocol here
protocol ColorSwitchable {
    func switchColor(_ color: Color)  
    // Remember that protocols are just guidelines not implementations
}

enum LightState {
  case On, Off
}

enum Color {
  case RGB(Double, Double, Double, Double)
  case HSB(Double, Double, Double, Double)
}

class WifiLamp {
  let state: LightState
  var color: Color

  init() {
    self.state = .On
    self.color = .RGB(0,0,0,0)
  }
}

EDIT: I had to make a change because I did not see that you added the switchColor method to the WifiLamp class and removed it. You will most likely do that in stage 2 when you make WifiLamp conform to ColorSwitchable.

Good Luck

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Matt Baldwin

Matt Baldwin

Protocols in Swift 3

1 Answer

Steven Deutsch

Steven Deutsch