Problem to set a OnClickListener

Hi everyone, I am new to Xamarin, I have a problem. Here are my codes:

using System;

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

namespace Music_Exchanger
{
[Activity(Label = "Music Exchanger", MainLauncher = true, Icon = "@drawable/icon")]
public class Activity1 : Activity
{

    protected override void OnCreate(Bundle bundle)
    {
        base.OnCreate(bundle);

        // Set our view from the "main" layout resource
        SetContentView(Resource.Layout.Main);
        Button Send_Button = FindViewById<Button>(Resource.Id.Send_Button);
        Send_Button.SetOnClickListener(this);


    }
    public override void OnClick(View V)
    { 
    //do sth...

    }
}

}

I receive an error: Error 1 'Music_Exchanger.Activity1.OnClick(Android.Views.View)': no suitable method found to override

In java, it works

package com.example.xxxxx;

import android.os.Bundle;
import android.app.Activity;
import android.view.*;
import android.view.View.OnClickListener;
import android.widget.Button;

public class MainActivity extends Activity implements OnClickListener

{

@Override
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    Button mybutton=(Button)findViewById(R.id.button1);
    mybutton.setOnClickListener(this);

}


@Override
public void onClick(View V) {


}

}

I don't know why. What is the correct way to do it?? If you know, please tell me, thanks!