WKWebView捕获HTML弹出的Alert和Confirm

之前用WebView装载一个网页时，弹出Alert时会显示网址，由于不想把网址暴露给用户这样显示就不是很友好了。UIWebView文档内没有找到可以捕获这类信息的API。GOOGLE了下发现了WKWebView组件，WKWebView是IOS8新推出的组件，目的是给出一个新的高性能的 Web View 解决方案，摆脱过去 UIWebView 的老旧笨重特别是内存占用量巨大的问题。以下为示例代码：

//
//  ViewController.swift
//  KenWKWebView
//
//  Created by KenNgai on 10/10/15.
//  Copyright © 2015 IT. All rights reserved.
//
 
import UIKit
import WebKit //导入WebKit  WKWebView应该是用Webkit内核
 
class ViewController: UIViewController,WKNavigationDelegate,WKUIDelegate {
 
    var wkBrowser:WKWebView!
     
    override func viewDidLoad() {
        super.viewDidLoad()
        self.wkBrowser = WKWebView(frame: self.view.frame)
        //self.wkBrowser.loadRequest(NSURLRequest(URL: NSURL(string: "http://www.baidu.com")!))
        let html = "<html><title>Dialog</title><style type='text/css'>body{font-size:60px}</style><script type='text/javascript'>function myconfirm(){if(confirm('Star it?')){alert('Done')}}</script><body><a href=\"javascript:alert('Just Alert')\" >Alert</a><br /><a href=\"javascript:myconfirm()\">Logout</a></body></html>"
        self.wkBrowser.loadHTMLString(html, baseURL: nil)
        self.wkBrowser.navigationDelegate = self
        self.wkBrowser.UIDelegate = self
        self.view.addSubview(wkBrowser)
    }
     
 
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
 
}
 
//捕捉异常信息
private typealias wkNavigationDelegate = ViewController
extension wkNavigationDelegate {
    func webView(webView: WKWebView, didFailNavigation navigation: WKNavigation!, withError error: NSError) {
        NSLog(error.debugDescription)
    }
     
    func webView(webView: WKWebView, didFailProvisionalNavigation navigation: WKNavigation!, withError error: NSError) {
        NSLog(error.debugDescription)
    }
}
 
private typealias wkUIDelegate = ViewController
extension wkUIDelegate {
    //HTML页面Alert出内容
    func webView(webView: WKWebView, runJavaScriptAlertPanelWithMessage message: String, initiatedByFrame frame: WKFrameInfo, completionHandler: () -> Void) {
        let ac = UIAlertController(title: webView.title, message: message, preferredStyle: UIAlertControllerStyle.Alert)
        ac.addAction(UIAlertAction(title: "Ok", style: UIAlertActionStyle.Cancel, handler: { (a) -> Void in
            completionHandler()
        }))
         
        self.presentViewController(ac, animated: true, completion: nil)
    }
     
    //HTML页面弹出Confirm时调用此方法
    func webView(webView: WKWebView, runJavaScriptConfirmPanelWithMessage message: String, initiatedByFrame frame: WKFrameInfo, completionHandler: (Bool) -> Void) {
        let ac = UIAlertController(title: webView.title, message: message, preferredStyle: UIAlertControllerStyle.Alert)
        ac.addAction(UIAlertAction(title: "Ok", style: UIAlertActionStyle.Default, handler:
            { (ac) -> Void in
                completionHandler(true)  //按确定的时候传true
        }))
         
        ac.addAction(UIAlertAction(title: "Cancel", style: UIAlertActionStyle.Cancel, handler:
            { (ac) -> Void in
                completionHandler(false)  //取消传false
        }))
         
        self.presentViewController(ac, animated: true, completion: nil)
    }
}