Swift4.0开发笔记
2017-11-03 本文已影响256人
星星编程
目录
1、ATS配置
2、状态栏全局变亮白
3、懒加载
4、内存泄漏
5、常用的第三方库
6、反射机制
7、运行时
8、MD5加密
9、聊天界面
10、多线程GCD
11、 启动图尺寸大小
1、ATS配置
App 网络http请求已被禁止，需要在Info.plist文件配置。
<key>NSAppTransportSecurity</key>
<dict>
<key>NSAllowsArbitraryLoads</key>
<true/>
</dict>
2、状态栏全局变亮白
UIApplication.shared.statusBarStyle = .lightContent
还需要在Info.plist文件配置：
<key>UIViewControllerBasedStatusBarAppearance</key>
<false/>
3、懒加载
lazy var mainScrollView:UIScrollView = {()-> UIScrollView in
let scrollView = UIScrollView()
return scrollView
}()
4、内存泄漏
解决闭包循环引用[weak self]
//ESPullToRefresh上拉加载
var footer: ESRefreshProtocol & ESRefreshAnimatorProtocol
footer = ESRefreshFooterAnimator.init(frame: CGRect.zero)
homeTableView.es.addInfiniteScrolling(animator: footer) { [weak self] in
self?.pageArray[tag]+=1
self?.initData(tag:tag+1,page:(self?.pageArray[tag]) ?? 1)
}
Timer释放内存
var timer:Timer?
override func viewDidLoad() {
super.viewDidLoad()
if #available(iOS 10.0, *) {
timer = Timer.scheduledTimer(withTimeInterval: 1, repeats: true, block: { (timer) in
print("定时器执行")
})
} else {
timer=Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(write), userInfo: nil, repeats: true)
}
timer?.fire() //启动定时器
//timer?.fireDate=Date.distantFuture //暂停定时器
}
@objc func write(){
print("定时器执行")
}
deinit{
timer?.invalidate()
timer=nil
print("销毁定时器")
}
CADisplayLink释放内存
let displayLink = CADisplayLink.init(target: self, selector: #selector(write))
displayLink?.frameInterval = 1
displayLink?.add(to: .current, forMode: .commonModes)
//displayLink?.isPaused=false//暂停或开始定时器
//销毁定时器必须先执行(deinit在这之后执行)
displayLink?.invalidate()
//然后再执行
displayLink=nil
WKWebView释放内存
//遵守WKScriptMessageHandler协议
webView = WKWebView.init(frame: self.view.bounds)
let request=URLRequest.init(url: URL.init(string: "http://www.jianshu.com/u/665ff1bc9038")!)
webView?.load(request)
webView?.configuration.userContentController.add(self, name: "Delete")
self.view.addSubview(webView!)
//实现代理方法
func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
if "Delete" == message.name {
}
}
//销毁WKWebView对象必须先执行(deinit在这之后执行)
webView?.configuration.userContentController.removeScriptMessageHandler(forName: "Delete")
//然后再执行
webView=nil
NotificationCenter通知
//发送通知
let center = NotificationCenter.default
center.post(name: NSNotification.Name(rawValue: "Notification"), object: "传单个值")
center.post(name: NSNotification.Name(rawValue: "Notification_More"), object: nil, userInfo: ["name":"星星编程","experience":"3年"])
//接收通知
var center = NotificationCenter.default
var observer:NSObjectProtocol?
override func viewDidLoad() {
super.viewDidLoad()
center.addObserver(self, selector: #selector(receive), name: NSNotification.Name(rawValue: "Notification"), object: nil)
observer = center.addObserver(forName: NSNotification.Name(rawValue: "Notification_More"), object: nil, queue: OperationQueue.main) { (notification) in
print(notification.userInfo ?? "")
}
}
@objc func receive(notification:Notification){
print("接收到消息：" + "\(notification.object ?? "")")
}
deinit {
//center.removeObserver(self)//销毁所以通知中心的监听，不能销毁NSObjectProtocol的监听
center.removeObserver(self, name: NSNotification.Name(rawValue: "Notification"), object: nil)
// center.removeObserver(observer ?? self)//销毁NSObjectProtocol的监听
center.removeObserver(observer ?? self, name: NSNotification.Name(rawValue: "Notification_More"), object: nil)
print("移除通知监听")
}
5、常用的第三方库
网络请求和生成Model的框架：AlamofireObjectMapper
首页图片轮播框架：GLLoopView
图片加载框架：Kingfisher
上拉刷新下拉加载框架：ESPullToRefresh
6、反射机制
Mirror
class Book : NSObject {
var name:String? //书名
var author:String? //作者
var pages:Int? //页数
}
let book = Book()
book.name = "简书"
book.author = "星星编程"
book.pages = 100
//是否是Book类的一个实例或实例的任何类继承自Book类
if book.isKind(of: Book.classForCoder()){
print("book是Book的一个实例")
}
//是否是Book类的一个实例
if book.isMember(of: Book.classForCoder()) {
print("book是Book的一个实例")
}
//判断self是否实现了aa方法
if self.responds(to: #selector(aa)){
print("aa")
}
//发送一个消息到指定消息的接收器,并返回结果
self.perform(#selector(aa))
//将对象进行反射
let mirror = Mirror(reflecting: book)
print("对象类型：\(mirror.subjectType)")
print("对象子元素个数：\(mirror.children.count)")
print("--- 对象子元素的属性名和属性值分别如下 ---")
for case let (key?, value) in mirror.children {
print("属性：\(key) 值：\(value)")
}
NSClassFromString
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
window = UIWindow()
window?.backgroundColor = UIColor.white
//设置跟控制器要添加命名空间（默认是项目名称，最好不要有特殊符号）
let clsName = "StarsSwift.ViewController"
let cls = NSClassFromString(clsName) as? UIViewController.Type
//使用类来创建视图控制器
let vc = cls?.init()
window?.rootViewController = vc
window?.makeKeyAndVisible()
return true
}
7、运行时
//通过KVC给对象赋值
let book = Book(dict: ["name" : "简书" , "author" : "星星编程" ,"introduction" : "假如编程欺骗了你，你依旧义无反顾的热爱编程，这才叫真爱。" ])
print("书名：\(book.name ?? "") 作者：\(book.name ?? "") 简介：\(book.introduction ?? "")")
//打印通过运行时获取类的属性
print(Book.propertyList())
//书类
class Book : NSObject{
@objc var name:String? //书名
@objc var author:String? //作者
@objc var introduction:String? //简介
init(dict:[String:Any]) {
super.init()
self.setValuesForKeys(dict)
}
override func setValue(_ value: Any?, forUndefinedKey key: String) {
}
class func propertyList()->[String]{
var count:UInt32=0
//获取类的属性列表，返回属性列表数组
let list=class_copyPropertyList(self, &count)
var propertyList=[String]()
for i in 0..<Int(count){
guard let pty = list?[i]
else{
continue
}
let cName=property_getName(pty)
guard let name = String.init(utf8String: cName) else{
continue
}
propertyList.append(name)
}
free(list)
return propertyList
}
}
8、MD5加密
//
// String+MD5.swift
// StarsSwift
//
// Created by 李永飞 on 2017/10/26.
// Copyright © 2017年 李永飞. All rights reserved.
//
import Foundation
extension String {
var md5: String {
if let data = self.data(using: .utf8, allowLossyConversion: true) {
let message = data.withUnsafeBytes { bytes -> [UInt8] in
return Array(UnsafeBufferPointer(start: bytes, count: data.count))
}
let MD5Calculator = MD5(message)
let MD5Data = MD5Calculator.calculate()
var MD5String = String()
for c in MD5Data {
MD5String += String(format: "%02x", c)
}
return MD5String
} else {
return self
}
}
}
9、聊天界面
消息列表.png
好友列表.png
聊天界面.png
10、多线程GCD
加载网络数据及时更新UI
DispatchQueue.global().async {
//加载网络数据
DispatchQueue.main.async(execute: {
//更新UI
})
}
延迟加载
DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + 1, execute: {
//更新UI
})
DispatchGroup
let group = DispatchGroup()
let queueTask1 = DispatchQueue(label: "book")
queueTask1.async(group: group) {
print("任务1" )
}
let queueTask2 = DispatchQueue(label: "video")
queueTask2.async(group: group) {
print("任务2" )
}
group.notify(queue: DispatchQueue.main) {
print("任务完成" )
}
DispatchWorkItem
let queueTask = DispatchQueue(label: "queueTask", attributes: .concurrent)
let workItem1 = DispatchWorkItem {
print("WorkItem1")
}
let workItem2 = DispatchWorkItem {
print("WorkItem2")
}
queueTask.async(execute: workItem1)
queueTask.async(execute: workItem2)
DispatchGroup和DispatchWorkItem一起使用
let group = DispatchGroup()
let queueTask1 = DispatchQueue(label: "book")
queueTask1.async(group: group) {
print("任务1" )
}
let queueTask2 = DispatchQueue(label: "video")
queueTask2.async(group: group) {
print("任务2" )
}
let queueTask = DispatchQueue(label: "queueTask", attributes: .concurrent)
let workItem1 = DispatchWorkItem {
print("WorkItem1")
}
let workItem2 = DispatchWorkItem {
print("WorkItem2")
}
queueTask.async(group: group, execute: workItem1)
queueTask.async(group: group, execute: workItem2)
group.notify(queue: DispatchQueue.main) {
print("任务完成" )
}
11、 启动图尺寸大小
iPhone Portrait iOS 11+ iPhone X （1125×2436） @3x
iPhone Portrait iOS 8,9-Retina HD 5.5 （1242×2208） @3x
iPhone Portrait iOS 8,9-Retina HD 4.7 （750×1334） @2x
iPhone Portrait iOS 7,8,9-2x （640×960） @2x
iPhone Portrait iOS 7,8,9-Retina 4 （640×1136） @2x
iPhone Portrait iOS 5,6-1x （320×480） @1x
iPhone Portrait iOS 5,6-2x （640×960） @2x
iPhone Portrait iOS 5,6-Retina4 （640×1136） @2x
