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iOS Protocols in Swift Protocol Basics Protocols With Methods

Lana Wong
Lana Wong
3,968 Points
Posted by Lana Wong
Lana Wong
3,968 Points

What is wrong with the declaring of my method?

INSTRUCTIONS: 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.

I do not understand what is wrong with my switchColor method

protocols.swift 
// 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

Michael Hulet
Michael Hulet
47,912 Points
Michael Hulet
Michael Hulet
47,912 Points

There are 2 things I see wrong here. First of all, there needs to be a space between the underscore (_) and the color parameter name. In Swift, and underscore (_) is just a placeholder for nothing in many cases, such as variable and parameter names. However, it's its own distinct symbol, and needs to be separated from all other symbols. As it is, your declaration is for a function called switchColor(_color:), but the question asks for a function called switchColor(_:). Furthermore, function declarations in protocols cannot have bodies, so the extra opening and closing brackets after your declaration are not necessary