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iOS Protocols in Swift Protocol Basics Protocols With Methods

Swift 3.0 - Protocols with Methods (Code Challenge)

I have looked at other people's code, but it didn't fix the error. This is probably some small mistake that I have overlooked, and I would probably be able to find it... If only I had the Preview button... :(

Thanks for helping.

// Declare protocol here
protocol ColorSwitchable {
  func switchColor(_ color: Color)

enum LightState {
  case on, off

enum Color {
  case rgb(Double, Double, Double, Double)
  case hsb(Double, Double, Double, Double)

class WifiLamp: ColorSwitchable {
  let state: LightState
  var color: Color // I tried replacing Color with switchColor, still didn't work.

  init() {
    self.state = .on
    self.color = .rgb(0, 0, 0, 0)

func switchColor(_ color: Color) {


Nevermind, I gots it. I didn't know how protocols worked. You have to put the switchColor method inside the body of the WifiLamp class and then:

self.color = color