Android开启新线程播放背景音乐

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  xmlns:tools="http://schemas.android.com/tools"  android:id="@+id/linearLayout1"  android:layout_width="fill_parent"  android:layout_height="fill_parent"  android:orientation="vertical" >     <Button    android:id="@+id/button1"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:text="开始" />   </LinearLayout> 

package com.example.test;  import android.app.Activity; import android.media.MediaPlayer; import android.media.MediaPlayer.OnCompletionListener; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button;  public class MainActivity extends Activity{  private Thread thread;//声明一个线程对象  private static MediaPlayer mp=null;//声明一个MediaPlayer对象  @Override  public void onCreate(Bundle savedInstanceState) {   super.onCreate(savedInstanceState);   setContentView(R.layout.main);      Button startButton=(Button)findViewById(R.id.button1);//获取开始按钮   startButton.setOnClickListener(new OnClickListener() {        @Override    public void onClick(View v) {      ((Button)v).setEnabled(false);//设置按钮不可用      //创建一个用于播放背景音乐的线程      thread=new Thread(new Runnable(){        @Override      public void run() {       playBGSound();//播放背景音乐             }        });      thread.start();//开启线程    }   });     }    private void playBGSound() {   if(mp!=null){    mp.release();//释放资源   }   mp=MediaPlayer.create(MainActivity.this, R.raw.flower);   mp.start();   //为MediaPlayer添加播放完成事件监听   mp.setOnCompletionListener(new OnCompletionListener() {        @Override    public void onCompletion(MediaPlayer mp) {     try {      Thread.sleep(5000);//让线程休眠5秒      <span style="white-space:pre">   </span>playBGSound();//重新播放音乐     } catch (InterruptedException e) {      // TODO Auto-generated catch block      e.printStackTrace();     }         }   });  }    @Override  protected void onDestroy() {   if(mp!=null){    mp.stop();    mp.release();    mp=null;   }   if(thread!=null){    thread=null;   }   super.onDestroy();  }   }