stevenchou1130

enum Team {
    case iOS
    case android
}

protocol Engineer {
    var team: Team { get }
    var canDevelopiOS: Bool { get }
}

stevenchou1130

protocol Swiftable {
    var isKnowSwift: Bool { get }
}

struct Steven: Engineer, Swiftable {
    let team: Team
    let canDevelopiOS: Bool
    let isKnowSwift: Bool
}

stevenchou1130

protocol Swiftable {
    var isKnowSwift: Bool { get }
}

protocol Engineer {
    var team: Team { get }
    var canDevelopiOS: Bool { get }
}

extension Engineer {

stevenchou1130

struct Sam: Engineer {
    let team: Team
}

let sam = Sam(team: .android)
print("Sam can develop iOS: \(sam.canDevelopiOS)”)
// Sam can develop iOS: false

stevenchou1130

struct Sam: Engineer {
    let team: Team
    let canDevelopiOS: Bool
}

let sam = Sam(team: .android, canDevelopiOS: true)
print("Sam can develop iOS: \(sam.canDevelopiOS)”)
// Sam can develop iOS: true

stevenchou1130

struct Sam: Engineer, Swiftable {
    let team: Team
    let isKnowSwift: Bool
}

let sam = Sam(team: .android, isKnowSwift: true)
print("Sam can develop iOS: \(sam.canDevelopiOS)")
// Sam can develop iOS: true

stevenchou1130

protocol Engineer: CustomStringConvertible {
    var team: Team { get }
    var canDevelopiOS: Bool { get }
}

extension CustomStringConvertible where Self: Engineer {
    var description: String {
        switch team {
        case .android:
            return "I belong to Android team."

stevenchou1130

print(steven.description)
// I belong to iOS team.

stevenchou1130

import UIKit
import SwiftyJSON

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {

stevenchou1130

let appVersion = Bundle.main.infoDictionary!["CFBundleShortVersionString"] as? String
let storeVersion = json["results"][0]["version"].stringValue
if appVersion == storeVersion {
 // 已是最新版本
} else {
 // Do something
}