我一直在尝试将WKWebView集成为UIViewController中另一个webview的子视图。我已经能够加载内容并与Swift和JavaScript进行正确的通信。然而，没有任何数据操作的HTML内容加载时间接近2秒。
我还测试了在不加载任何脚本的情况下只加载空HTML体的WKWebView。这仍然需要600毫秒来加载。

viewDidLoad与**webView（webView：WKWebView，didFinishNavigation导航：WKNavigation！）**为600毫秒，如果HTML包含空正文。
ViewController的viewDidLoad函数

override func viewDidLoad() {
    NSLog("started - %@.%@", String(self.dynamicType), __FUNCTION__)
    super.viewDidLoad()
    
    let wkConfiguration: WKWebViewConfiguration = WKWebViewConfiguration()
    let userController: WKUserContentController = WKUserContentController()
    wkConfiguration.userContentController = userController
    wkConfiguration.processPool = VCWKWebView.wkProcess
    self.wkWebView = VCWKWebView(frame: self.webView.bounds,configuration: wkConfiguration)
    if let wkWebView = self.wkWebView {
        self.webView.addSubview(wkWebView)
        wkWebView.translatesAutoresizingMaskIntoConstraints = false
        let height = NSLayoutConstraint(item: wkWebView, attribute: .Height, relatedBy: .Equal, toItem: self.webView, attribute: .Height, multiplier: 1, constant: 0)
        let width = NSLayoutConstraint(item: wkWebView, attribute: .Width, relatedBy: .Equal, toItem: self.webView, attribute: .Width, multiplier: 1, constant: 0)
        webView.addConstraints([height, width])
        //wkWebView.delegate = self
        wkWebView.navigationDelegate = self
        wkWebView.loadContent()
    }
    
    NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillShow:", name: UIKeyboardWillShowNotification, object: nil)
    NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillHide:", name: UIKeyboardWillHideNotification, object: nil)
    
    NSLog("ended - %@.%@", String(self.dynamicType), __FUNCTION__)
}

VCWKWebView类：

class VCWKWebView: WKWebView  {
    
    static let wkProcess: WKProcessPool = WKProcessPool()
    
    private static let _url: NSURL = NSURL(fileURLWithPath: NSBundle.mainBundle().pathForResource("index", ofType: "html",inDirectory:"www")!)

    private static let _accessUrl: NSURL = NSURL(fileURLWithPath: NSBundle.mainBundle().pathForResource("www", ofType: nil)!)

    
    func loadContent(){
        NSLog("started - %@.%@", String(self.dynamicType), __FUNCTION__)
        if #available(iOS 9.0, *) {
            self.loadFileURL(VCWKWebView._url, allowingReadAccessToURL: VCWKWebView._accessUrl)
        } else {
            // Fallback on earlier versions
        }
        NSLog("ended - %@.%@", String(self.dynamicType), __FUNCTION__)
    }
    
    override init(frame: CGRect, configuration: WKWebViewConfiguration) {
        super.init(frame:frame, configuration:configuration)
    }
    
    convenience init(frame: CGRect){
        let wkConfiguration: WKWebViewConfiguration = WKWebViewConfiguration()
        self.init(frame:frame,configuration:wkConfiguration)
    }
    
    deinit{
        print("deinit of VCWKWebView is called")
    }
}