多个按钮的onclick

package com.example.pengtuanyuan.openweb;

import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements View.OnClickListener{

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Button bt_click=(Button)findViewById(R.id.bt_click);
        Button button=(Button)findViewById(R.id.button);
        Button button2=(Button)findViewById(R.id.button2);
        Button button3=(Button)findViewById(R.id.button3);
        Button button4=(Button)findViewById(R.id.button4);

        bt_click.setOnClickListener(new MyOnclickListener());

        button.setOnClickListener(this);
        button2.setOnClickListener(this);
        button3.setOnClickListener(this);
        button4.setOnClickListener(this);


    }

    @Override
    public void onClick(View v) {
        int id=v.getId();
        switch (id){
            case R.id.button:
                open_web();
                break;
            case R.id.button2:
                System.out.println("Button 2 be checked");
                break;
            case R.id.button3:
                System.out.println("Button 3 be checked");
                break;
            case R.id.button4:
                Toast.makeText(this,"Button 4 be checked",Toast.LENGTH_SHORT).show();
                break;
            default:
                break;

        }


    }

    class MyOnclickListener implements View.OnClickListener {

        @Override
        public void onClick(View view) {
            open_web();
        }
    }

    private void open_web() {
        Intent intent=new Intent();
        intent.setAction(Intent.ACTION_VIEW);
        intent.setData(Uri.parse("https://www.hao123.com"));
        startActivity(intent);
    }
}