class ViewController: UIViewController {

  var webView: WKWebView!
  @IBOutlet weak var progressView: UIProgressView!
    
  required init(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)!
    
    // 实例化 WKWebView
    self.webView = WKWebView(frame: CGRectZero)
  }
  
 
  override func viewDidLoad() {
    super.viewDidLoad()

    // 编程式加入 WKWebView
    view.addSubview(webView)
    view.insertSubview(webView, aboveSubview: progressView)
    webView.translatesAutoresizingMaskIntoConstraints = false
    
    let widthConstraint = NSLayoutConstraint(item:webView, attribute: .Width, relatedBy: .Equal, toItem: view, attribute: .Width, multiplier: 1 , constant: 0)
    view.addConstraint(widthConstraint)
    
    let heightConstraint = NSLayoutConstraint(item:webView,attribute: .Height, relatedBy: .Equal,toItem: view, attribute: .Height, multiplier:1, constant: -46)
    
    view.addConstraint(heightConstraint)
    
    // 检测webView对象属性的变化
    webView.addObserver(self, forKeyPath: "loading", options: .New, context: nil)
    webView.addObserver(self, forKeyPath: "title", options: .New, context: nil)
    
    //加载网页

    let request = NSURLRequest(URL: NSURL(string: "http://ray.dotnetage.com")!)
    
    webView.loadRequest(request)
    
  }


  override func observeValueForKeyPath(keyPath: String?, ofObject object: AnyObject?, change: [String : AnyObject]?, context: UnsafeMutablePointer<Void>) {
  
    if (keyPath == "loading") {

      // 检测按钮的可用性
      forwardButton.enabled = webView.canGoBack
      backButton.enabled = webView.canGoBack
      stopButton.image = webView.loading ? UIImage(name: "Cross") : UIImage(named: "Syncing")

    } else if keyPath == "title" {

      title = webView.title

    } else if keyPath == "estimatedProgress" {

      progressView.hidden = webView.estimatedProgress == 1
      progressView.setProgress(Float(webView.estimatedProgress), animated: true)

    }
  }
}

// ViewController.swift

import WebKit

class ViewController : UIViewController {

 var webView: WKWebView!

 required init(coder aDecoder: NSCoder) {
   super.init(coder: aDecoder)!
   

   let configuation = WKWebViewConfiguration()

   configuation.userContentController.addUserScript(getUserScript("inject"))
   
   self.webView = WKWebView(frame: CGRectZero,configuration: configuation)
 }

  // 从资源中读取 javascript 脚本
  func getUserScript(fromName: String)-> WKUserScript {
    let filePath = NSBundle.mainBundle().pathForResource(fromName, ofType: "js")
    let js = try! String(contentsOfFile: filePath!, encoding: NSUTF8StringEncoding)
    return WKUserScript(source: js, injectionTime: .AtDocumentEnd, forMainFrameOnly: true)
  }
 ...
}

$("#mybutton").click(function(){
  webkit.messageHandlers.openPhotoLibrary.postMessage();
});

/*! A class conforming to the WKScriptMessageHandler protocol provides a
 method for receiving messages from JavaScript running in a webpage.
 */
public protocol WKScriptMessageHandler : NSObjectProtocol {
  
  /*! @abstract Invoked when a script message is received from a webpage.
   @param userContentController The user content controller invoking the
   delegate method.
   @param message The script message received.
   */
  @available(iOS 8.0, *)
  public func userContentController(userContentController: WKUserContentController, didReceiveScriptMessage message: WKScriptMessage)
}

class ViewController: UIViewController, WKScriptMessageHandler {


  required init(coder aDecoder: NSCoder) {

    // ... 之前的代码同上

    configuation.userContentController.addScriptMessageHandler(self, name: "openPhotoLibrary")

    self.webView = WKWebView(frame: CGRectZero,configuration: configuation)
  }

  ...


  func userContentController(userContentController: WKUserContentController, didReceiveScriptMessage message: WKScriptMessage) {
    if message.name == "openPhotoLibrary" {
      // 这里就可以加入打开相册的代码了
    }
  }
}

var menus = $(".navbar a").map(function(n,i){
  return {
    title: $(n).text,
    link: $(n).attr("href")
  };
});

webkit.messageHandlers.didFetchMenus.postMessage(menus);

var menus: [Menus]?

func userContentController(userContentController: WKUserContentController, didReceiveScriptMessage message: WKScriptMessage) {
  if message.name == "didFetchMenus" {
    if let resultArray = message.body as? [Dictionary<String,String>] {
      menus = resultArray.map{ Menu(dict: $0) }

      // 这里就取出并将JSON转换为 Swift 的Menu对象了
      print(menus)
    }
  }
}

import UIKit
import SafariServices

class ViewController: UIViewController {
  @IBAction func openBrowser(sender: AnyObject) {
    let safari = SFSafariViewController(URL:NSURL(string:"http://www.apple.com")!)
      
    self.showViewController(safari, sender: self)
  }
}