Swift实现一句代码不用写加载首次启动引导图

#

kImageNamsArray:引导页的图片数组
kHiddenBtnImageName: 关闭引导页的按钮图片
kHiddenBtnCenter: 关闭引导页按钮的位置

实现原理

1.给Appdelegate增加扩展, 添加guaidWindow属性

 private struct AssociatedKeys {
        static var guideWindowKey = "guideWindowKey"
    }

    private var guaidWindow: UIWindow? {

        get {
            return objc_getAssociatedObject(self, &AssociatedKeys.guideWindowKey) as? UIWindow
        }

        set {
            if newValue != nil {
                objc_setAssociatedObject(self, &AssociatedKeys.guideWindowKey, newValue, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
            }
        }
    }

2.通过运行时进行方法的交换

public override class func initialize(){

        DispatchQueue.once(token: "交换appDelegate方法") {
            let lastVersion = UserDefaults.standard.float(forKey: "lastVersionKey")
            let currentVersion = Float((Bundle.main.infoDictionary?["CFBundleShortVersionString"] as? String) ?? "0")!
            if currentVersion > lastVersion {
                let originalMethod = class_getInstanceMethod(self, #selector(application(_:didFinishLaunchingWithOptions:)))
                let customMethod = class_getInstanceMethod(self, #selector(guide_application(_:didFinishLaunchingWithOptions:)))
                method_exchangeImplementations(originalMethod, customMethod)
            }

        }

    }


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


        guaidWindow = UIWindow()
        guaidWindow!.frame = UIScreen.main.bounds
        guaidWindow!.backgroundColor = UIColor.white
        guaidWindow!.windowLevel = UIWindowLevelStatusBar + 1
        self.guaidWindow!.makeKeyAndVisible()

        let vc = ZSGuaidViewController()
        vc.hide = {[weak self] in
            print("1111")
            let currentVersion = Float((Bundle.main.infoDictionary?["CFBundleShortVersionString"] as? String) ?? "0")!
            UserDefaults.standard.set(currentVersion, forKey: "lastVersionKey")
            UserDefaults.standard.synchronize()

            self?.guaidWindow?.resignKey()
            self?.guaidWindow?.isHidden = true
            self?.guaidWindow = nil
        }

        guaidWindow?.rootViewController = vc
        return guide_application(application, didFinishLaunchingWithOptions: launchOptions)
    }

}

Demo地址觉得有用给个��, Demo也实现了一句话加载广告页.