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iOS Protocols in Swift Protocol Basics Protocols With Methods

Dmitry Vashlaev
Dmitry Vashlaev
2,715 Points
Posted by Dmitry Vashlaev
Dmitry Vashlaev
2,715 Points

Protocols

Hello, I have some troubles with this code. It seems to be ok but it's not working. Any ideas?

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

Lucian Rotari
Lucian Rotari
12,007 Points
Lucian Rotari
Lucian Rotari
12,007 Points

Hi Dimitry, you have got all right but you just missed one important thing.

Just read this sentence careful

For the sake of this challenge, make sure your external argument label is omitted by using an underscore.

I just copied and paste your code snipped and added a underscore for external argument.

So your code must look like that: 

protocol ColorSwitchable {
  func switchColor( _ color: Color)
}

But I found this on apple guides

As with type property requirements, you always prefix type method requirements with the static keyword when they’re defined in a protocol.

However it works without 'static' as well.

Dmitry Vashlaev
Dmitry Vashlaev
2,715 Points
Dmitry Vashlaev
Dmitry Vashlaev
2,715 Points

I didn't get the task right, thank you for help.

Lucian Rotari
Lucian Rotari
12,007 Points
Lucian Rotari
Lucian Rotari
12,007 Points

You can read more about this on Apple documentation or “The swift programing language” provided by Apple