I have defined a UIWebViewDelegate class and instantiated it in the Delegate property of my UIWebView, but the ShouldStartLoad method is not being called when the webview loads a request. What am I doing wrong? 

Here is the code defining my UIWebViewDelegate and my UIWebView:

```cs
public class MyWebViewDelegate: UIWebViewDelegate
{
    private UIWebView _view;
    public MyWebViewDelegate (UIWebView view)
    {
         _view = view;
    }   
    public override bool ShouldStartLoad (UIWebView webView, 
                                          MonoTouch.Foundation.NSUrlRequest request,
                                          UIWebViewNavigationType navigationType)
    {
        System.Console.WriteLine("Starting load");
        return true;
    }
}

public class MyWebView : UIWebView
{
   private static MyWebView _instance = new MyWebView ();
   private MyWebView () : base()
   {
       this.Delegate = new MyWebViewDelegate(this);
   }
   public static MyWebView Instance {
       get { return _instance; }
   }
   public void Load ()
   {
       this.LoadRequest (new NSUrlRequest(NSUrl.FromString("http://myurl"),
                           NSUrlRequestCachePolicy.ReloadIgnoringLocalAndRemoteCacheData,
                           5)
                        );
   }
}

```

In my appdelegate I am then doing the following in *FinishedLaunching* method:

```cs
// Create form view controller
viewControllerForm = new UIViewController();
viewControllerForm.View = MyWebView.Instance;
viewControllerForm.Title = Localization.Translate("Forms");

// Load webview
MyWebView.Instance.Load();

```

Note that I have used copy/paste to give this code sample, so there could be some minor copy/paste errors here, but my code is compiling and the webview loads the request; it is just that the *ShouldStartLoad* that is not being called.

Does anyone have any idea what I am doing wrong here?