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iOS Protocols in Swift Protocol Basics Protocols With Methods

Evan Bloom
Evan Bloom
2,607 Points
Posted by Evan Bloom
Evan Bloom
2,607 Points

I don't know what I am doing wrong for task 2. I have to set color to the new color. Please help!!!

I am not sure what I am doing wrong.

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: ColorSwitchable {
  let state: LightState
  var color: Color

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

func switchColor (_ color: Color) {
     self.color = color
}

2 Answers

Chris Stromberg
PLUS
Chris Stromberg
Courses Plus Student 13,389 Points
Chris Stromberg
Chris Stromberg
Courses Plus Student 13,389 Points

Check your placement of the following code:

func switchColor (_ color: Color) {
     self.color = color
}
Evan Bloom
Evan Bloom
2,607 Points
Evan Bloom
Evan Bloom
2,607 Points

Thanks Chris!!

Bharath Chandrashekar
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Bharath Chandrashekar
iOS Development with Swift Techdegree Graduate 12,055 Points
Bharath Chandrashekar
.a{fill-rule:evenodd;}techdegree seal-36
Bharath Chandrashekar
iOS Development with Swift Techdegree Graduate 12,055 Points

You have done almost everything right. The only thing missed - Your method definition should be within the class and not outside. Something like this: 

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

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

    func switchColor(_ color: Color) {
        self.color = color
    }
}

The class WifiLamp adopts the ColorSwitchable protocol and hence the method declared in the protocol should be defined inside the WifiLamp class.

Hope this helps.

Evan Bloom
Evan Bloom
2,607 Points
Evan Bloom
Evan Bloom
2,607 Points

Thanks Bharath Chandrashekar!! It worked!!