使用webView的UITapGestureRecognizer

Question

我正在使用webView，我希望在用户点击webView时执行某些操作，因为我使用UITapGestureRecognizer这样的方式：

import UIKit

class ViewController: UIViewController, UIGestureRecognizerDelegate {

@IBOutlet var webView: UIWebView!
let SingleTap = UITapGestureRecognizer()

override func viewDidLoad() {
    super.viewDidLoad()

    super.viewDidLoad()
    let url = NSURL(string: "http://rshankar.com")
    let request = NSURLRequest(URL: url!)
    webView.loadRequest(request)

    SingleTap.delegate = self
    SingleTap.addTarget(self, action: "SingleTap:")
    SingleTap.numberOfTapsRequired = 1
    SingleTap.numberOfTouchesRequired = 1
    self.webView!.scrollView.addGestureRecognizer(SingleTap)
}

func SingleTap(gestureRecognizer:UIGestureRecognizer){
    println("touch detected")
    }
}

但这对我不起作用，以后我会这样尝试同样的事情：

    let aSelector : Selector = "UserTap:"
    let tapGesture = UITapGestureRecognizer(target: self, action: aSelector)
    tapGesture.numberOfTapsRequired = 1
    self.webView.addGestureRecognizer(tapGesture)

    func userTap(tapgesture : UITapGestureRecognizer){
    println("user tapped")
    }

但它不适合我。

我错过了一些事情，请帮助我。在此先感谢。