c# – MonoDroid：未处理的异常恢复

我发现Android / MonoDroid提供了三种机制,据我所知,应该可以实现这一点,但我无法让它们中的任何一种工作.这是我的代码：

using System;
using Android.App;
using Android.Content;
using Android.Runtime;
using Android.Views;
using Android.Widget;
using Android.OS;

namespace TestApp {
    [Android.App.Activity(Label = "TestApp",MainLauncher = true,Icon = "@drawable/icon")]
    public class MainActivity : Activity {
        protected override void OnCreate(Bundle bundle) {
            base.OnCreate(bundle);
            SetContentView(new LinearLayout(this));

            //set up handlers for uncaught exceptions:
            //Java solution
            Java.Lang.Thread.DefaultUncaughtExceptionHandler = new ExceptionHandler(this);
            //MonoDroid solution #1
            AndroidEnvironment.UnhandledExceptionRaiser += AndroidEnvironment_UnhandledExceptionRaiser;
            //MonoDroid solution #2
            AppDomain.CurrentDomain.UnhandledException += delegate { new Alert(this,"AppDomain.CurrentDomain.UnhandledException","error"); };

            //throw an exception to test
            throw new Exception("uncaught exception");
        }

        void AndroidEnvironment_UnhandledExceptionRaiser(object sender,RaiseThrowableEventArgs e)
        {
            //found a suggestion to set the Handled flag=true,but it has no effect
            new Android.Runtime.RaiseThrowableEventArgs(e.Exception).Handled = true;
            new Alert(this,"AndroidEnvironment.UnhandledExceptionRaiser","error");
        }
    }

    public class ExceptionHandler : Java.Lang.Object,Java.Lang.Thread.IUncaughtExceptionHandler {
        private Context _context;
        public ExceptionHandler(Context c) { _context = c; }
        public void UncaughtException(Java.Lang.Thread thread,Java.Lang.Throwable ex) {
            new Alert(_context,"java exception handler");
        }
    }

    public class Alert {
        public Alert(Context c,string src,string title = "alert") {
            Android.App.AlertDialog.Builder builder = new Android.App.AlertDialog.Builder(c);
            builder.SetTitle(title);
            builder.SetMessage(src);
            builder.SetPositiveButton("Ok",delegate { });
            Android.App.AlertDialog alert = builder.Create();
            alert.Show();
        }
    }
}

任何帮助将不胜感激,谢谢！