如何为此代码添加第二个按钮？

Question

package com.example.progressdialog;

import com.example.progressdialog.R;

import android.os.Bundle;
import android.app.Activity;
import android.app.ProgressDialog;
import android.view.Menu;
import android.view.View;

public class MainActivity extends Activity {

   private ProgressDialog progress;
   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
      progress = new ProgressDialog(this);
   }


   public void open(View view){
      progress.setMessage("Doing Progressive Things");
      progress.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
      progress.setIndeterminate(false);
      progress.show();

   final int totalProgressTime = 100;

   final Thread t = new Thread(){

   @Override
   public void run(){

      int jumpTime = 0;
      while(jumpTime < totalProgressTime){
         try {
            sleep(500);
            jumpTime += 1;
            progress.setProgress(jumpTime);
         } catch (InterruptedException e) {


           e.printStackTrace();
         }

      }

   }
   };
   t.start();

   }
   @Override
   public boolean onCreateOptionsMenu(Menu menu) {

      getMenuInflater().inflate(R.menu.main, menu);
      return true;
   }
}

如何在程序中添加第二个按钮？我想添加第二个按钮，允许我在我的应用程序中打开另一个窗口。我无法弄清楚我想把第二个onclick监听器放在哪里。谁能帮助我？