import UIKit
@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
var window: UIWindow?
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
// Override point for customization after application launch.
//設(shè)置window大小，UIScreen.main.bounds獲取屏幕大小
self.window = UIWindow(frame: UIScreen.main.bounds)
//設(shè)置背景顏色
self.window?.backgroundColor = #colorLiteral(red: 0.4745098054, green: 0.8392156959, blue: 0.9764705896, alpha: 1)
//設(shè)置window成為主屏幕，并顯示
self.window?.makeKeyAndVisible()
//創(chuàng)建根控制器
self.window?.rootViewController = UIViewController()
//設(shè)置子視圖（紅色）
//創(chuàng)建子視圖（視圖位置，視圖大?。?/p>
let redView = UIView(frame: CGRect(x: 0, y: 0, width: 200, height: 200))
//視圖背景顏色
redView.backgroundColor = UIColor.red
//視圖tag值（視圖唯一標(biāo)識(shí)）
redView.tag = 201
//設(shè)置視圖中心點(diǎn)
redView.center = (window?.center)!
//將視圖切成圓形（半徑）
redView.layer.cornerRadius = 100
//將視圖添加到主屏幕
self.window?.addSubview(redView)
//黃色（下同）
let yellowView = UIView(frame: CGRect(x: 0, y: 0, width: 150, height: 150))
yellowView.backgroundColor = UIColor.yellow
yellowView.tag = 202
yellowView.center = (window?.center)!
yellowView.layer.cornerRadius = 75
yellowView.center = (window?.center)!
self.window?.addSubview(yellowView)
//藍(lán)色（下同）
let blueView = UIView(frame: CGRect(x: 0, y: 0, width: 100, height: 100))
blueView.backgroundColor = UIColor.blue
blueView.tag = 203
blueView.center = (window?.center)!
blueView.layer.cornerRadius = 50
self.window?.addSubview(blueView)
//定時(shí)器：參數(shù)1:定時(shí)執(zhí)行的間隔，參數(shù)2:執(zhí)行目標(biāo)，參數(shù)3:目標(biāo)對(duì)象選擇執(zhí)行的方法，參數(shù)4:用戶信息（nil），參數(shù)5:定時(shí)器是否重復(fù)執(zhí)行
Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(chengeColor), userInfo: nil, repeats: true)
return true
}
//定時(shí)器方法
func chengeColor(){
//
let redView = self.window?.viewWithTag(201)
//存儲(chǔ)顏色
let color = redView?.backgroundColor
//交換顏色
self.window?.viewWithTag(201)?.backgroundColor = self.window?.viewWithTag(202)?.backgroundColor
self.window?.viewWithTag(202)?.backgroundColor = self.window?.viewWithTag(203)?.backgroundColor
self.window?.viewWithTag(203)?.backgroundColor = color
}
func applicationWillResignActive(_ application: UIApplication) {
// Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
// Use this method to pause ongoing tasks, disable timers, and invalidate graphics rendering callbacks. Games should use this method to pause the game.
}
func applicationDidEnterBackground(_ application: UIApplication) {
// Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
// If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
}
func applicationWillEnterForeground(_ application: UIApplication) {
// Called as part of the transition from the background to the active state; here you can undo many of the changes made on entering the background.
}
func applicationDidBecomeActive(_ application: UIApplication) {
// Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
}
func applicationWillTerminate(_ application: UIApplication) {
// Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
}
}
