//assets文件下的mp3播放

        try
        {
            AssetManager assets = getAssets();
            AssetFileDescriptor openFd = assets.openFd("music001.mp3");
            FileDescriptor fileDescriptor = openFd.getFileDescriptor();
            MediaPlayer mediaPlayer = new MediaPlayer();
            //下面的表明从哪里播放，播放多久的时间，更专业点 ！！！！
//            mediaPlayer.setDataSource(fileDescriptor, openFd.getStartOffset(), openFd.getLength());
            mediaPlayer.setDataSource(fileDescriptor);
            mediaPlayer.prepare();
            mediaPlayer.start();
            //循环！！！！
            mediaPlayer.setLooping(true);
        }
        catch (IOException e1)
        {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        }

//sdcard的MP3

//播放应用的资源文件(res/raw/)
     try
    {
        MediaPlayer mediaPlayer = MediaPlayer.create(this, R.raw.music001);

//不用prepare()设这个就播放不了，直接start()就可以了，调试调试debug

//可能prepare()是针对setDataSource（）而言，这里没有setDataSource（）就不需要prepare（）了
       // mediaPlayer.prepare();
        mediaPlayer.start();
        mediaPlayer.setLooping(true);
    }
    catch (IllegalStateException e)
    {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

private void ShowMp3List() {
  Cursor cursor = this.getContentResolver().query(
    MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,//音频的uri
    new String[] { MediaStore.Audio.Media.TITLE,    //歌曲名称
      MediaStore.Audio.Media.DURATION,    //歌曲持续的时间
      MediaStore.Audio.Media.ARTIST,       //歌手
      MediaStore.Audio.Media._ID,             //歌曲id
      MediaStore.Audio.Media.DISPLAY_NAME,
      MediaStore.Audio.Media.DATA,       //歌曲文件路径
      MediaStore.Audio.Media.ALBUM_ID }, null, null, null);
 
  if (null != cursor && cursor.getCount() == 0) {
   builder = new AlertDialog.Builder(this);
   builder.setMessage(R.string.music_list_tell).setPositiveButton(
     "aa", null);
   ad = builder.create();
   ad.show();
   listviews.setBackgroundResource(R.drawable.list_empty);
   return;

  }

  cursor.moveToFirst();//验证游标是否为空

  
 
  while(cursor.moveToNext){
   id = cursor.getInt(3);
   title= cursor.getString(0);
   artist = cursor.getString(2);
   path = cursor.getString(5).substring(4);
   alltime=(toTime(cursor.getInt(1)));

System.out.println(id+""+title+artist+path+alltime)
    }
  listview.setAdapter(new SimpleCursorAdapter(this, R.layout.item_listview, cursor, new String[]{MediaStore.Audio.Media._ID
                ,MediaStore.Audio.Media.ARTIST,MediaStore.Audio.Media.TITLE}, new int[]{R.id.imageView1,R.id.textView1,R.id.textView2}));

 }

/////////////////////////////////////////////////////////

MediaStore类是Android平台的多媒体数据库，它包含了音频，视频，图片等所有多媒体文件信息
media  是媒体的意思

MediaStore以ContentProvider的形式向外提供媒体数据库信息。通过Android平台提供的ContentProvider接口，可以方便的访问数据库信息。

MediaStore.Audio.Media类定义了媒体数据库中的歌曲信息
     歌曲ID：MediaStore.Audio.Media._ID
     歌曲的名称 ：MediaStore.Audio.Media.TITLE
     MediaStore.Audio.Artists类定义了媒体数据库中的歌手信息
     MediaStore.Audio.Albums类定义了媒体数据库中的专辑信息
     MediaStore.Audio.Playlists类定义了媒体数据库中的播放列表信息
     歌曲文件的路径 ：MediaStore.Audio.Media.DATA
     歌曲的总播放时长 ：MediaStore.Audio.Media.DURATION
     歌曲文件的大小 ：MediaStore.Audio.Media.SIZE
     MediaStore.Audio.Media.DISPLAY_NAME     歌曲id 歌首 歌名（1 周杰伦-爱的怒放.mp3）
     audio   adj. 听觉的，声音的；音频的

//fragment碎片

package com.wuxifu.musiclist;

import com.example.tabhost002.R;
import com.wuxifu.widget.MyPlayer;
import com.wuxifu.widget.MyService.MyBinder;

import android.database.Cursor;
import android.os.Binder;
import android.os.Bundle;
import android.provider.MediaStore;
import android.support.v4.app.Fragment;
import android.support.v4.app.ListFragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.Button;

public class SearchaLocalMusicFragment extends ListFragment
{
    private Button search;
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState)
    {
        View inflate = inflater.inflate(R.layout.local_music, null);
        search =(Button) inflate.findViewById(R.id.search);
        iniSearch();
        return inflate;
    }
    private void iniSearch()
    {
       
    }
    private MyPlayer myPlayer;
    private MyBinder binder;
    @Override
    public void onActivityCreated(Bundle savedInstanceState)
    {
        super.onActivityCreated(savedInstanceState);
        String[] projection=new String[] { MediaStore.Audio.Media.TITLE,
                MediaStore.Audio.Media.DURATION,
                MediaStore.Audio.Media.ARTIST,
                MediaStore.Audio.Media._ID,
                MediaStore.Audio.Media.DISPLAY_NAME,
                MediaStore.Audio.Media.DATA,
                MediaStore.Audio.Media.ALBUM_ID };
        final Cursor cursor = getActivity().getContentResolver().query(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, projection, null, null, null);
        if(!cursor.moveToFirst())
        {
            Log.e("cursor", "cursor为空 ");
            return ;
        }
       setListAdapter(new MusicListAdapter(getActivity(), cursor));
       getListView().setOnItemClickListener(new OnItemClickListener()
    {

        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position,
                long id)
        {
            if(myPlayer==null || binder==null){
            myPlayer = (MyPlayer)getActivity().getSupportFragmentManager().findFragmentById(R.id.fragment1);
            binder = myPlayer.getmBinder();
            }
            //先要让cursor移动要那一行，才能取那一行某列的数据，否则不行的
           if( cursor.moveToPosition(position)){
            String string=cursor.getString(cursor.getColumnIndex(MediaStore.Audio.Media.DATA));
            binder.play(string);
           }
            }
    });
    }
}
///////////////////////////////

Cursor android.content.ContentResolver.query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder)

如   select id,name,age  from  wuxifu  where  id in (15,20)   order by age;

 String[] projection=new String[]{"id","name","age"}

//错的：：：：String selection=new String[]{"id"}

//正确的：：：：：

String selection=“id  in  (?,?)  ”;

String selectionArgs=new String[]{"110","20"};