How to do it...

1. Create a new playground file in Xcode called Protocols as usual.
2. Complete the following example using the following protocol:

      protocol VehicleProtocol{ 
        // properties 
        var name: String {set get} // settable and gettable 
        var canFly: Bool {get} // gettable only (readonly) 
    
        // instance methods 
        func numberOfWheels() ->Int 
        func move() 
        func stop() 
    
        // class method 
        staticfuncpopularBrands() -> [String] 
      } 
 
      class Bicycle: VehicleProtocol{ 
        var name: String 
        var canFly: Bool{ 
          return false 
      } 
    
      init(name: String){ 
      self.name = name 
      } 
    
      func numberOfWheels() -> Int { 
        return 2 
      } 
      func move() { 
       // move logic goes here 
      } 
      func stop() { 
       // stop logic goes here 
      } 
      static func popularBrands() -> [String] { 
        return ["Giant", "GT", "Marin", "Trek", "Merida", "Specialized"] 
      } 
    } 
 
    class Car: VehicleProtocol{ 
      var name: String 
      var canFly: Bool{ 
        return false 
      } 
    
    init(name: String){ 
      self.name = name 
    } 
    
    funcnumberOfWheels() ->Int { 
      return 4 
    } 
    func move() { 
      // move logic goes here 
    } 
    func stop() { 
      // stop logic goes here 
    } 
    static func popularBrands() -> [String] { 
      return ["Audi", "BMW", "Honda", "Dodge", "Lamborghini", "Lexus"] 
    } 
  } 
 
  let bicycle1 = Bicycle(name: "Merida 204") 
  bicycle1.numberOfWheels() // 2 
 
  let car1 = Car(name: "Honda Civic") 
  car1.canFly  // false 
 
  Bicycle.popularBrands() // Class function 
  // ["Giant", "GT", "Marin", "Trek", "Merida", "Specialized"] 
  Car.popularBrands() // ["Audi", "BMW", "Honda", "Dodge", "Lamborghini", "Lexus"]