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iOS Protocols in Swift Protocol Basics Protocols With Methods

Ryan Clark
Ryan Clark
2,832 Points

How dos this work in Xcode but not here?

Is it something silly Im missing?

// 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 {
  let state: LightState
  var color: Color

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

1 Answer

David Papandrew
David Papandrew
8,386 Points

In your ColorSwitchable protocol, you need a single space between the function's external name (underscore) and the internal name (color).

func switchColor(_ color: Color)