{
  "tz": 8,
  "area": "HK",
  "tz_name": "Asia/Hong_Kong",
  "id": "101819729",
  "current": {
    "current_version": "69e14038fd7bbe93ec5a259e36b48173"
  },
  "name": "Hong Kong",
  "province": "Hong Kong"
}
//WTKit can read json and parse to class like below,
//and the model class's instances can update json value to their properties
public class WeatherModel: NSObject,WTJSONModelProtocol {
    var tz:String?
    var area:String?
    var tz_name:String?
    var id:String?
    var name:String?
    var province:String?
    var current:CurrentModel?
    var day:DayModel?
    public func WTJSONModelClass(for property:String)->AnyObject?{
        if (property == "current") {
            return CurrentModel()
        }
        return nil
    }
}
public class CurrentModel: NSObject {
    var current_version:String?
    public func WTJSONModelClass(for property:String)->AnyObject?{
        return CurrentDetailModel()
    }
}

//auto update property from json data
weatherModel.wt(travel: jsonObject)

Note that the WTJSONModelProtocol protocol is implemented in the class that contains the custom properties so that the program knows what data is available at runtime

public func WTPrint<T>(_ items:T,
             separator: String = " ",
             terminator: String = "\n",
             file: String = #file,
             method: String = #function,
             line: Int = #line)

WTPrint("wt print \(self)")
//AppDelegate.swift[19], application(_:didFinishLaunchingWithOptions:) wt print <WTKit.AppDelegate: 0x7fde38509d80>

import WTKit
let task = WTKit.dataTask(with: "https://www.apple.com") 
task.completionHandler = { [weak self](data, response, error) in
              print(response) //response
              print(data)     //data
              print(error)    //error
        }

let task = WTKit.dataTask(with: "https://www.apple.com") 
task.completionHandler = { [weak self](data, response, error) in
              print(response) //response
              print(data)     //data
              print(error)    //error
        }

task.stringHandler = {(string:String?,error:NSError?)in
            print(string)
        }

task.jsonHandler = {(object:AnyObject?,error:NSError?) in
            print(object)
        }

import WTKit
imageView.wt_setImage(with: imageURL, placeHolder: placeHolderImage)

//convert to string(utf-8)
public func toUTF8String()->String
//parse json
public func parseJson()->AnyObject?

OperationQueue.main {
    let thread = Thread.current()
    print("main:\(thread) threadPriority:\(thread.threadPriority) qualityOfService:\(thread.qualityOfService.rawValue)")
}
OperationQueue.background {
    let thread = Thread.current()
    print("background:\(thread) threadPriority:\(thread.threadPriority) qualityOfService:\(thread.qualityOfService.rawValue)")

}
OperationQueue.userInteractive {
    let thread = Thread.current()
    print("userInteractive:\(thread) threadPriority:\(thread.threadPriority) qualityOfService:\(thread.qualityOfService.rawValue)")
}
OperationQueue.globalQueue {
    let thread = Thread.current()
    print("globalQueue:\(thread) threadPriority:\(thread.threadPriority) qualityOfService:\(thread.qualityOfService.rawValue)")
}

/*
//print
main:<NSThread: 0x7fbd40e04f40>{number = 1, name = main} threadPriority:0.758064516129032 qualityOfService:-1
globalQueue:<NSThread: 0x7fbd40c18b60>{number = 5, name = (null)} threadPriority:0.5 qualityOfService:-1
userInteractive:<NSThread: 0x7fbd40d10c10>{number = 3, name = (null)} threadPriority:0.5 qualityOfService:33
background:<NSThread: 0x7fbd40c7c540>{number = 4, name = (null)} threadPriority:0.0 qualityOfService:9

*/

let string = "swift"
print(string.length)//5

// Get just one calendar unit value
 public func numberFor(component unit:Calendar.Unit)->Int{

date.numberFor(component: .year)
//2016

let date = Date()
print("year:\(date.numberForComponent(.year)) month:\(date.numberForComponent(.month)) day:\(date.numberForComponent(.day))")
//year:2016 month:6 day:15        

var reachability:WTReachability = WTReachability.reachabilityWithHostName("www.apple.com")
reachability.startNotifier()
NotificationCenter.default().addObserver(forName: NSNotification.Name(rawValue: kWTReachabilityChangedNotification), object: nil, queue: nil) { [weak self](notification) in
            let reachability:WTReachability = notification.object as! WTReachability
            print(reachability.currentReachabilityStatus())
        }

UIColor.colorWithHexString("#3")//result is #333333
UIColor.colorWithHexString("333333")//result is #333333
UIColor.colorWithHexString("#333333")//result is #333333
UIColor.colorWithHexString("ff0000",alpha: 0.5)//red color with alpha : 0.5

//build version
UIApplication.buildVersion()
//app version
let appVersion:String = UIApplication.appVersion()
//documents path
let docPath:String = UIApplication.documentsPath()


//check if this launch is first launch,can use for everywhere,even use twice
UIApplication.firstLaunchForBuild { [weak self](isFirstLaunchEver) in
            if isFirstLaunchEver{
                print("this is first launch")
            }else{
                print("this is not first launch")
            }
        }

requestButton.setImageWith("url", forState: .Normal,placeHolder: nil)

let image:UIImage = (self.imageView.image?.imageWithRoundCornerRadius(30))

//set image with a url
imageView.setImageWith("url")

//set hight lighted image with a url,and set a place holder image
imageView.sethighlightedImageWith("url", placeHolder: placeHolderImage)

//hide loading
self.showLoadingView()

//hide loading
self.hideLoadingView()


//tip at bottom
self.showHudWithTip("热烈欢迎")

let image:UIImage = self.view.snapShot()//get a snap shot image
let pdf:Data = self.view.pdf()//get a pdf shot

//closure to refresh
self.tableView.refreshHeader = RefreshHeader.headerWithRefreshing({
            print("refresh data from internet")
        })

//stop Loading
self.tableView.stopLoading()

//local settings,default is English
tableView.refreshHeader?.setTitle("加载中...", forState: .Loading)
tableView.refreshHeader?.setTitle("下拉刷新", forState: .PullDownToRefresh)
tableView.refreshHeader?.setTitle("松开刷新", forState: .ReleaseToRefresh)
tableView.refreshHeader?.dateStyle = "yyyy-MM-dd"
tableView.refreshHeader?.lastUpdateText = "上次刷新时间"
//refresh image
tableView.refreshHeader?.arrowImageURL = "http://ww4.sinaimg.cn/mw690/47449485jw1f4wq45lqu6j201i02gq2p.jpg"

let image:UIImage =  self.view.layer.snapShot()
//pause animation
self.view.layer.pauseAnimation()
//resume animation
self.view.layer.resumeAnimation()