Android 酷炫来袭：制作属于你自己的音频播放器（综合运用MediaPlayer、Service、Broadcast、ListView、SeekBar）

　　
　　今天制作了一个属于自己的音乐播放器感觉还不错，分享出来，希望能够帮助大家。感觉知识点挺多的，也挺使用的，大大提高了个人兴趣，哈哈，我是程序员啊程序员。
为了有所侧重，我将注意点和学习点放在文章的最开篇。

一、学习重点与注意点

1、Mediaplayer的生命周期、相关方法及其使用
2、如何自定义SeekBar
3、接收广播的动态注册与注销
4、获取文件路径
5、获取歌曲的名称、作者名、图片
6、Service服务的使用

二、Mediaplayer介绍

　　想要制作一个属于自己的风格样式的音乐播放器，首先我们要学会使用音乐播放器。

Mediaplayer的生命周期

具体的查看API，这里附一张生命周期图。

　　Mediaplayer的证明周期中我们可以看出，Mediaplayer开始的时候需要调用reset()方法，然后是setDataResource()-prepare()-start()在MediaPlayer开启之后，我们可以让它暂停和停止等操作。
reset()：将Mediaplayer对象重置到刚刚创建的状态。
setDataResource()：设置要播放的音频文件的位置。
prepare()：在开始播放之前调用这个方法完成准备工作（使用之前需要设置prepare监听）。
start()：开始或继续播放音频文件
seekTo()：从指定位置开始播放
stop():停止播放音频。
getDuration():获取载入的音频文件的时长
getCurrentPosition()：获取音频文件的当前播放位置

简单的使用方法

点击按钮设置音频播放

public class MainActivity extends Activity implements OnClickListener{
    private Button mbtn_start;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mbtn_start=(Button) findViewById(R.id.bt_start);
        mbtn_start.setOnClickListener(this);
        //获取文件路径，如果我们不知道文件具体放在那里可以通过log打印出来

        File musicDir=Environment.getExternalStorageDirectory();
        Log.d("音乐", Environment.getExternalStorageDirectory().getAbsolutePath());

        musicDir = new File(musicDir, "/musics");

        Toast.makeText(getApplicationContext(), Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MUSIC).getAbsolutePath(),
                Toast.LENGTH_LONG).show();
        File[] files=musicDir.listFiles();//获取所有的文件
        for(File file:files){
            Log.d("路径", file.getAbsolutePath());
            }
    }
    @Override
    public void onClick(View v) {
        switch (v.getId()) {
        case R.id.bt_start:
        //new 一个新Mediaplayer对象，按照生命周期顺序操作
            MediaPlayer mediaplayer=new MediaPlayer();
            mediaplayer.reset();
            File musicDir=Environment.getExternalStorageDirectory();        

            File[] files=musicDir.listFiles();//获取所有的文件
            for(File file:files){
                Log.d("路径", file.getAbsolutePath());
            }
            try {

                mediaplayer.setDataSource(files[23].getAbsolutePath());
                mediaplayer.prepare();
                //设置prepare监听器，查看是否准备好，可以开始？
                mediaplayer.setOnPreparedListener(new OnPreparedListener() {

                    @Override
                    public void onPrepared(MediaPlayer mp) {              //准备好了之后开始播放
                        mp.start();

                    }
                });
            } catch (IllegalStateException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }               
            break;

        default:
            break;
        }
    }   
}

注意：我们还需要在manifest中获取读sdcard的权限。

三、制作音频播放器

Ⅰ 开启音乐并使音乐能够在后台运行

1、制作布局，ListView（+子布局+Adapter）+SeekBar+TextView+ToggleButton
2、循序渐进：书写MusicService类继承Service (这里别忘记在manifest中注册)，为了保证音乐能够在后台运行，在之后的步骤中我们将在MusicService中创建线程，开启音乐。
3、开启MusicService：在MainActivity中获得文件路径，通过Intent的putStringArrayListExtra的方法传递给MusicService，并监听listview的item点击事件找到要播放的文件的position传递给Service。
4、在MusicService中创建线程，开启音乐

①布局+ListView+子布局+Adapter

在布局中我们顺便学习一下自定义SeekBar样式
新建xml文件，设置点击图片

<selector xmlns:android="http://schemas.android.com/apk/res/android" >
    <item android:drawable="@drawable/list_btn_radio_check_on" android:state_focused="true" android:state_window_focused="true">item>
 <item android:drawable="@drawable/list_btn_radio_check_on" android:state_selected="true" android:state_window_focused="true">item>
  <item android:drawable="@drawable/list_btn_radio_check_on" android:state_pressed="true" android:state_window_focused="true">item>
   <item android:drawable="@drawable/list_btn_radio_check_off" >item>
selector>

SeekBar引用（通过设置Thumb）

  <SeekBar
        android:id="@+id/seekbar"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:progress="20"
        android:thumb="@drawable/seekbarimg" 
        android:layout_weight="1"/>

Adapter

public class MusicAdapter extends BaseAdapter {
    private LayoutInflater minflate;
    //传递所有文件路径
    private File[] musicDirs;

    public MusicAdapter(LayoutInflater minflate, File[] musicDirs) {
        super();
        this.minflate = minflate;
        this.musicDirs = musicDirs;
    }

    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return musicDirs.length;
    }

    @Override
    public Object getItem(int position) {
        // TODO Auto-generated method stub
        return position;
    }

    @Override
    public long getItemId(int position) {
        // TODO Auto-generated method stub
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder vh = null;
        if (convertView == null) {
            vh = new ViewHolder();
            convertView = minflate.inflate(R.layout.item_music_name, null);
            vh.mtextview = (TextView) convertView
                    .findViewById(R.id.textview_music_name);
            vh.mtextview_author = (TextView) convertView
                    .findViewById(R.id.textview_author_name);
            vh.img = (ImageView) convertView.findViewById(R.id.img);
            convertView.setTag(vh);
        } else {
            vh = (ViewHolder) convertView.getTag();
        }
        vh.mtextview.setText(musicDirs[position].getName());
        //通过MediaMetadataRetriever的对象来获取音频文件的
        //歌名、歌手、自带的图片
        MediaMetadataRetriever mnr = new MediaMetadataRetriever();
        Log.d("路径", musicDirs[position].getAbsolutePath());
        mnr.setDataSource(musicDirs[position].getAbsolutePath());
        String author = mnr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_ARTIST);
        //获取作者名，不为空对textview进行重新设置
        if (author != null) {
            vh.mtextview_author.setText(author);
        } else {
            vh.mtextview_author.setText("<未知>");
        }
        //获取二进制图片
        byte[] img = mnr.getEmbeddedPicture();
        if (img != null) {
        //将二进制文件转换成位图进行添加专辑图片
            Bitmap bitmap = BitmapFactory.decodeByteArray(img, 0, img.length);
            vh.img.setImageBitmap(bitmap);
        } else {
            vh.img.setImageResource(R.drawable.audio_identify_singer_default);
        }

        return convertView;
    }

    class ViewHolder {
        TextView mtextview;
        TextView mtextview_author;
        ImageView img;
    }
}

这里我们将重点学习的地方提取出来。
获取作者与图片

//通过MediaMetadataRetriever的对象来获取音频文件的
        //歌名、歌手、自带的图片
        MediaMetadataRetriever mnr = new MediaMetadataRetriever();
        Log.d("路径", musicDirs[position].getAbsolutePath());
        mnr.setDataSource(musicDirs[position].getAbsolutePath());
        String author = mnr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_ARTIST);

    //获取二进制图片
        byte[] img = mnr.getEmbeddedPicture();
        if (img != null) {
        //将二进制文件转换成位图进行添加专辑图片
            Bitmap bitmap = BitmapFactory.decodeByteArray(img, 0, img.length);
            vh.img.setImageBitmap(bitmap);
        } else {
            vh.img.setImageResource(R.drawable.audio_identify_singer_default);
        }

②获取并传递音频文件路径，开启Service

musicDir = Environment.getExternalStorageDirectory();
        musicDir = new File(musicDir, "/musics");
        files = musicDir.listFiles();

Intent intent = new Intent(getApplicationContext(), MusicService.class);

        intent.putStringArrayListExtra("all_music_path", files_path);

        startService(intent);

监听ListView
在这里每次点击后开启服务，设置开始键样式为

    @Override
    public void onItemClick(AdapterView parent, View view, int position,
            long id) {
            //设置为选中状态，样式改变
        mradoibutton_start.setChecked(true);
        Intent intent = new Intent(getApplicationContext(), MusicService.class);
        intent.putExtra("type", Config.START_NEW_MUSIC_LISTVIEW);
        intent.putExtra("music_position",position );        
        intent.putExtra("all_music_path", files_path);
        startService(intent);
    }

③Service中创建线程，开启音乐

在onStartCommand方法中调用而不是onCreate方法 ，因为在每次服务启动的时候该方法都会调用，而onCreate方法则是只有在服务被创建的时候才被调用。

  public void  startNewMusiclistview(){
        if(mediaplayer==null){
            mediaplayer=new MediaPlayer();
        }
             mediaplayer.reset();             
                try {

                    mediaplayer.setDataSource(musicspath.get(musicposition).toString());
                    mediaplayer.prepare();
                    mediaplayer.setOnPreparedListener(new OnPreparedListener() {

                        @Override
                        public void onPrepared(MediaPlayer mp) {
                            mediaplayer.start();

                            mediaplayer.getCurrentPosition();
                            int duration=mediaplayer.getDuration();
                            Intent  intent2=new Intent("play");
                            intent2.putExtra("type", 0);
                            intent2.putExtra("totaltime",mediaplayer.getDuration());
                             intent2.putExtra("ischecked", true);
                 //这里发送广播给MainActivity，将总时间传递给SeekBar
                            sendBroadcast(intent2);
                    //开启线程，发送广播给MainActivity                
                    //用于与seekbar关联，设置SeekBar进度
                            MyThreadPlay  myplaythread=new MyThreadPlay();
                            myplaythread.start();
                        }
                    });
                    //为了循环播放音乐，对当前音频的播放完成情况进行检测
                    //使它能够在播放完一首歌曲之后播放下一首歌曲
                   mediaplayer.setOnCompletionListener(new OnCompletionListener() {

                    @Override
                    public void onCompletion(MediaPlayer mp) {
        //最后一个文件时，让位置重新回到开始，通过递归进行循环播放
            if(musicposition==musicspath.size()-1){
                            musicposition=0;
                        }else{
                            musicposition++;
                        }                   
                        startNewMusiclistview();
                    }
                });
                } catch (IllegalArgumentException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (SecurityException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (IllegalStateException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }                                   
    }

Ⅱ创建线程，发送广播与SeekBar可拖动滚动条关联

①由音频文件属性设置Seekbar进度

MusicService中发送广播

 class MyThreadPlay extends Thread{
       @Override
    public void run() {
           while(mediaplayer.isPlaying()){             
               Intent intent=new Intent("play");
               intent.putExtra("type", 1);
               intent.putExtra("currentime", mediaplayer.getCurrentPosition());

               sendBroadcast(intent);

               try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
           }

    }
   }

MainActivity接收
注意接收者在mainActivity中的动态注册与注销
动态注册BroadcastReceiver

receiver = new MyReceiver();
        IntentFilter filter = new IntentFilter();
        filter.addAction("play");
        registerReceiver(receiver, filter);

BroadcastReceiver的继承类

//该类用于接收MusicService发过来的广播，用于设置textview与seekbar
class MyReceiver extends BroadcastReceiver {
        @Override
        public void onReceive(Context context, Intent intent) {

            int type = intent.getIntExtra("type", 0);
            //由于我们获得的时间是毫秒数，因此要进行相应转换
             Date date = new Date();    
             SimpleDateFormat format=new SimpleDateFormat("mm:ss");
             //通过判断intent的type来确定设置进度还是设置时间
            switch (type) {
            case 0:
                int duration = intent.getIntExtra("totaltime", 0);

                  date.setTime(duration);

                String  format_duration= format.format(date);
                //设置seekbar最大值，这样才能控制进度
                mseekbar.setMax(duration);
                mtv_totaltime.setText("" + format_duration);
                break;
            case 1:
                 currenttime = intent.getIntExtra("currentime", 0);

                  date.setTime(currenttime);
                String  format_currenttime= format.format(date);
                mtv_currenttime.setText(format_currenttime);
                mseekbar.setProgress(currenttime);
                break;
            default:
                break;
            }
        }
    }

注销BroadcastReceiver

    @Override
    protected void onDestroy() {

        super.onDestroy();
        unregisterReceiver(receiver);
    }

②通过监听SeekBar的进度改变音频文件进度

上面的代码中我们只实现了音频文件对SeekBar进度的改变时不行的，下面我们通过对SeekBar的监听来改变音频文件

mseekbar.setOnSeekBarChangeListener(this);

  //SeekBar改变过程中时调用
    @Override
    public void onProgressChanged(SeekBar seekBar, int progress,
            boolean fromUser) {
    }
    //SeekBar开始改变时调用
    @Override
    public void onStartTrackingTouch(SeekBar seekBar) {
    }
 //SeekBar最终停止改变时调用，我们在这个方法中进行对音频文件的进度修改
    @Override
    public void onStopTrackingTouch(SeekBar seekBar) {
        Intent intent = new Intent(getApplicationContext(), MusicService.class);
        intent.putExtra("type", Config.SEEKTO);
        intent.putExtra("progress", mseekbar.getProgress());
        startService(intent);

    }

MusicService中进行修改进度

            int progress=intent.getIntExtra("progress", 0);
            mediaplayer.seekTo(progress);

Ⅲ上一曲、下一曲、开始、停止按钮的监听

MainActivity
上一曲、下一曲的监听只是传递的类型不同，只有停止开始按钮不太一样，因为它在开始与停止状态的图片有变化。

@Override
    public void onClick(View v) {
        Intent intent = new Intent(getApplicationContext(), MusicService.class);
        switch (v.getId()) {
        case R.id.bt_previeous:         
            intent.putExtra("type", Config.SELECT_PREVIOUS_BY_TOGGLEBUTTON);
            startService(intent);
            break;
        case R.id.bt_next:
            intent.putExtra("type", Config.SELECT_NEXT_BY_TOGGLEBUTTON);
            startService(intent);
            break;
        case R.id.bt_start:
            if(flag){
                intent.putExtra("type", Config.START_NOW_BY_TOGGLEBUTTON);
                intent.putExtra("mcurrenttime",currenttime);            
                startService(intent);
                flag=!flag;
            }else{              
                intent.putExtra("type", Config.PAUSE_NOW_BY_TOGGLEBUTTON);          
                startService(intent);
                flag=!flag;
            }

            break;
        default:
            break;
        }

MusicService中的只是把当前文件位置进行加、减、暂停、继续

int type=intent.getIntExtra("type",222);
    switch (type) {
        case Config.START_NEW_MUSIC_LISTVIEW:
            musicposition=intent.getIntExtra("music_position", 0);          
            currentposition=musicposition;
            startNewMusiclistview();
            break;
        case Config.SEEKTO:
            int progress=intent.getIntExtra("progress", 0);
            mediaplayer.seekTo(progress);
            break;
        case Config.START_NOW_BY_TOGGLEBUTTON:              
            int currenttime=intent.getIntExtra("mcurrenttime", 0);   
            while (!mediaplayer.isPlaying()) {
                mediaplayer.start();
            }


        //  startNewMusiclistview();        
            break;
        case Config.PAUSE_NOW_BY_TOGGLEBUTTON:
            while (mediaplayer.isPlaying()) {
                mediaplayer.pause();
            }

            break;
        case Config.SELECT_PREVIOUS_BY_TOGGLEBUTTON:
            Log.d("musicString",currentposition +"");
            if(currentposition==0){
                musicposition=musicspath.size()-1;

            }else{
                musicposition--;

            }
            currentposition=musicposition;
            startNewMusiclistview();
            break;
        case Config.SELECT_NEXT_BY_TOGGLEBUTTON:
            if(currentposition==musicspath.size()-1){
                musicposition=0;
            }else{
                musicposition++;
            }
            currentposition=musicposition;
            startNewMusiclistview();
            break;
        case 222:break;
        default:
            break;
        }   

ⅣConfig.class文件

该文件中专门用于存放判别type的常量

package com.example.mymediaplayerdemo;

public class Config {
  public static final int START_NEW_MUSIC_LISTVIEW=0x01;
  public static final int SEEKTO=0x02;
  public static final int START_NOW_BY_TOGGLEBUTTON=0x03;
  public static final int PAUSE_NOW_BY_TOGGLEBUTTON=0x04;
  public static final int SELECT_PREVIOUS_BY_TOGGLEBUTTON=0x05;
  public static final int SELECT_NEXT_BY_TOGGLEBUTTON=0x06;
}

主要代码

MainActivity

public class MainActivity extends Activity implements OnClickListener,
        OnSeekBarChangeListener, OnItemClickListener {
    private ListView mlistview;
    private TextView mtv_currenttime;
    private TextView mtv_totaltime;

    private ToggleButton mradoibutton_pre;
    private ToggleButton mradoibutton_start;
    private ToggleButton mradoibutton_next;
    private SeekBar mseekbar;

    private File musicDir;
    private File[] files;
    private int seekbarprogress;
    private MusicAdapter madapter;
    private LayoutInflater inflater;
    private MyReceiver receiver;
    private  ArrayList files_path=new ArrayList();
    private int currenttime;
    private boolean flag=false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.activity_main);
        mradoibutton_pre = (ToggleButton) findViewById(R.id.bt_previeous);
        mradoibutton_start = (ToggleButton) findViewById(R.id.bt_start);
        mradoibutton_next = (ToggleButton) findViewById(R.id.bt_next);
        mseekbar = (SeekBar) findViewById(R.id.seekbar);
        mlistview = (ListView) findViewById(R.id.listview);
        mtv_totaltime = (TextView) findViewById(R.id.textview_totaltime);
        mtv_currenttime = (TextView) findViewById(R.id.textview_currenttime);

        receiver = new MyReceiver();
        IntentFilter filter = new IntentFilter();
        filter.addAction("play");
        registerReceiver(receiver, filter);

        musicDir = Environment.getExternalStorageDirectory();
        musicDir = new File(musicDir, "/musics");
        files = musicDir.listFiles();

//      for (File file : files) {
//          Log.d("音乐文件", file.getName() + "路径" + file.getAbsolutePath());
//          
//      }
        for (int i = 0; i < files.length; i++) {

            files_path.add(files[i].getAbsolutePath().toString());
            Log.d("files_path", files_path.get(i));
            }

        Intent intent = new Intent(getApplicationContext(), MusicService.class);

        intent.putStringArrayListExtra("all_music_path", files_path);

        startService(intent);

        inflater = getLayoutInflater();
        madapter = new MusicAdapter(inflater, files);
        mlistview.setAdapter(madapter);
        mlistview.setOnItemClickListener(this);

        mradoibutton_pre.setOnClickListener(this);
        mradoibutton_start.setOnClickListener(this);                        
        mradoibutton_next.setOnClickListener(this);

        mseekbar.setOnSeekBarChangeListener(this);

    }

    @Override
    public void onItemClick(AdapterView parent, View view, int position,
            long id) {
        mradoibutton_start.setChecked(true);
        Intent intent = new Intent(getApplicationContext(), MusicService.class);
        intent.putExtra("type", Config.START_NEW_MUSIC_LISTVIEW);
        intent.putExtra("music_position",position );        
        intent.putExtra("all_music_path", files_path);
        startService(intent);
    }

    class MyReceiver extends BroadcastReceiver {



        @Override
        public void onReceive(Context context, Intent intent) {

            int type = intent.getIntExtra("type", 0);
             Date date = new Date();    
             SimpleDateFormat format=new SimpleDateFormat("mm:ss");
            switch (type) {
            case 0:
                int duration = intent.getIntExtra("totaltime", 0);

                  date.setTime(duration);

                String  format_duration= format.format(date);
                mseekbar.setMax(duration);
                mtv_totaltime.setText("" + format_duration);
                break;
            case 1:
                 currenttime = intent.getIntExtra("currentime", 0);

                  date.setTime(currenttime);
                String  format_currenttime= format.format(date);
                mtv_currenttime.setText(format_currenttime);
                mseekbar.setProgress(currenttime);
                break;
            default:
                break;
            }

        }

    }

    @Override
    protected void onDestroy() {

        super.onDestroy();
        unregisterReceiver(receiver);
    }

    @Override
    public void onProgressChanged(SeekBar seekBar, int progress,
            boolean fromUser) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onStartTrackingTouch(SeekBar seekBar) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onStopTrackingTouch(SeekBar seekBar) {
        Intent intent = new Intent(getApplicationContext(), MusicService.class);
        intent.putExtra("type", Config.SEEKTO);
        intent.putExtra("progress", mseekbar.getProgress());
        startService(intent);

    }

    @Override
    public void onClick(View v) {
        Intent intent = new Intent(getApplicationContext(), MusicService.class);
        switch (v.getId()) {
        case R.id.bt_previeous:         
            intent.putExtra("type", Config.SELECT_PREVIOUS_BY_TOGGLEBUTTON);
            startService(intent);
            break;
        case R.id.bt_next:
            intent.putExtra("type", Config.SELECT_NEXT_BY_TOGGLEBUTTON);
            startService(intent);
            break;
        case R.id.bt_start:
            if(flag){
                intent.putExtra("type", Config.START_NOW_BY_TOGGLEBUTTON);
                intent.putExtra("mcurrenttime",currenttime);            
                startService(intent);
                flag=!flag;
            }else{              
                intent.putExtra("type", Config.PAUSE_NOW_BY_TOGGLEBUTTON);          
                startService(intent);
                flag=!flag;
            }

            break;
        default:
            break;
        }
    }
}

MusicService

public class MusicService extends Service{
    private MediaPlayer mediaplayer;
    private  int musicposition;
    private ArrayList musicspath;
    private int currentposition;
    @Override
    public IBinder onBind(Intent intent) {
        // TODO Auto-generated method stub
        return null;
    }
    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        if(musicspath==null){
            musicspath=intent.getStringArrayListExtra("all_music_path");
        }   

        int type=intent.getIntExtra("type",222);
        switch (type) {
        case Config.START_NEW_MUSIC_LISTVIEW:
            musicposition=intent.getIntExtra("music_position", 0);          
            currentposition=musicposition;
            startNewMusiclistview();
            break;
        case Config.SEEKTO:
            int progress=intent.getIntExtra("progress", 0);
            mediaplayer.seekTo(progress);
            break;
        case Config.START_NOW_BY_TOGGLEBUTTON:              
            int currenttime=intent.getIntExtra("mcurrenttime", 0);   
            while (!mediaplayer.isPlaying()) {
                mediaplayer.start();
            }


        //  startNewMusiclistview();        
            break;
        case Config.PAUSE_NOW_BY_TOGGLEBUTTON:
            while (mediaplayer.isPlaying()) {
                mediaplayer.pause();
            }

            break;
        case Config.SELECT_PREVIOUS_BY_TOGGLEBUTTON:
            Log.d("musicString",currentposition +"");
            if(currentposition==0){
                musicposition=musicspath.size()-1;

            }else{
                musicposition--;

            }
            currentposition=musicposition;
            startNewMusiclistview();
            break;
        case Config.SELECT_NEXT_BY_TOGGLEBUTTON:
            if(currentposition==musicspath.size()-1){
                musicposition=0;
            }else{
                musicposition++;
            }
            currentposition=musicposition;
            startNewMusiclistview();
            break;
        case 222:break;
        default:
            break;
        }



        return super.onStartCommand(intent, flags, startId);
    }
  public void  startNewMusiclistview(){
        if(mediaplayer==null){
            mediaplayer=new MediaPlayer();
        }
             mediaplayer.reset();             
                try {

                    mediaplayer.setDataSource(musicspath.get(musicposition).toString());
                    mediaplayer.prepare();
                    mediaplayer.setOnPreparedListener(new OnPreparedListener() {

                        @Override
                        public void onPrepared(MediaPlayer mp) {
                            mediaplayer.start();

                            mediaplayer.getCurrentPosition();
                            int duration=mediaplayer.getDuration();
                            Intent  intent2=new Intent("play");
                            intent2.putExtra("type", 0);
                            intent2.putExtra("totaltime",mediaplayer.getDuration());
                             intent2.putExtra("ischecked", true);
                            sendBroadcast(intent2);

                            MyThreadPlay  myplaythread=new MyThreadPlay();
                            myplaythread.start();
                        }
                    });
                   mediaplayer.setOnCompletionListener(new OnCompletionListener() {

                    @Override
                    public void onCompletion(MediaPlayer mp) {
                        if(musicposition==musicspath.size()-1){
                            musicposition=0;
                        }else{
                            musicposition++;
                        }                   
                        startNewMusiclistview();
                    }
                });
                } catch (IllegalArgumentException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (SecurityException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (IllegalStateException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }                                   
    }
   class MyThreadPlay extends Thread{
       @Override
    public void run() {
           while(mediaplayer.isPlaying()){             
               Intent intent=new Intent("play");
               intent.putExtra("type", 1);
               intent.putExtra("currentime", mediaplayer.getCurrentPosition());           
               sendBroadcast(intent);       
               try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
           }

    }
   }
}

Adapter

public class MusicAdapter extends BaseAdapter {
    private LayoutInflater minflate;
    private File[] musicDirs;

    public MusicAdapter(LayoutInflater minflate, File[] musicDirs) {
        super();
        this.minflate = minflate;
        this.musicDirs = musicDirs;
    }

    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return musicDirs.length;
    }

    @Override
    public Object getItem(int position) {
        // TODO Auto-generated method stub
        return position;
    }

    @Override
    public long getItemId(int position) {
        // TODO Auto-generated method stub
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder vh = null;
        if (convertView == null) {
            vh = new ViewHolder();
            convertView = minflate.inflate(R.layout.item_music_name, null);
            vh.mtextview = (TextView) convertView
                    .findViewById(R.id.textview_music_name);
            vh.mtextview_author = (TextView) convertView
                    .findViewById(R.id.textview_author_name);
            vh.img = (ImageView) convertView.findViewById(R.id.img);
            convertView.setTag(vh);
        } else {
            vh = (ViewHolder) convertView.getTag();
        }
        vh.mtextview.setText(musicDirs[position].getName());
        MediaMetadataRetriever mnr = new MediaMetadataRetriever();
        Log.d("路径", musicDirs[position].getAbsolutePath());
        mnr.setDataSource(musicDirs[position].getAbsolutePath());
        String author = mnr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_ARTIST);
        if (author != null) {
            vh.mtextview_author.setText(author);
        } else {
            vh.mtextview_author.setText("<未知>");
        }
        byte[] img = mnr.getEmbeddedPicture();
        if (img != null) {
            Bitmap bitmap = BitmapFactory.decodeByteArray(img, 0, img.length);
            vh.img.setImageBitmap(bitmap);
        } else {
            vh.img.setImageResource(R.drawable.audio_identify_singer_default);
        }
        return convertView;
    }
    class ViewHolder {
        TextView mtextview;
        TextView mtextview_author;
        ImageView img;
    }
}