前言：小巫的简、美音乐播放器从5月7号开始开发，之前以为时间很充足，也没有估量整个软件的需求，如果简单实现基本的操作的话，确实可以在一个星期内把一个简单的音乐播放器给开发出来。不过我增加了很多特性，比如歌词的显示，专辑封面的显示，界面的左右切换，倒影效果实现等，让整个音乐播放器添色很多，与我之前想开发出操作简单，界面漂亮的想法一致，这是另我比较开心的。到目前为止实现了以下功能：

第1阶段完成的功能：

好啦，来看看整个软件的全貌吧：

  

  

以上就是简、美音乐播放器的全貌，是不是感觉蛮简美的哈。

下面是实现第二阶段功能的代码：

算了，我直接把整个Activity的代码贴出来，里面的代码也有做相应的修改的。不过你们直接看源码就好了。

/SimpleBeautyMusicPlayer/src/com/wwj/sb/activity/HomeActivity.java

package com.wwj.sb.activity;import java.io.File;import java.util.List;import android.app.Activity;import android.app.AlertDialog;import android.app.Service;import android.content.BroadcastReceiver;import android.content.ContentValues;import android.content.Context;import android.content.DialogInterface;import android.content.Intent;import android.content.IntentFilter;import android.graphics.Bitmap;import android.graphics.Color;import android.media.RingtoneManager;import android.net.Uri;import android.os.Bundle;import android.os.Vibrator;import android.provider.MediaStore;import android.view.ContextMenu;import android.view.ContextMenu.ContextMenuInfo;import android.view.KeyEvent;import android.view.LayoutInflater;import android.view.View;import android.view.View.OnClickListener;import android.view.View.OnCreateContextMenuListener;import android.view.ViewGroup.LayoutParams;import android.widget.AdapterView;import android.widget.AdapterView.OnItemClickListener;import android.widget.ArrayAdapter;import android.widget.Button;import android.widget.ImageView;import android.widget.ListView;import android.widget.RadioButton;import android.widget.RadioGroup;import android.widget.TextView;import android.widget.Toast;import com.wwj.sb.adapter.MusicListAdapter;import com.wwj.sb.domain.AppConstant;import com.wwj.sb.domain.Contsant;import com.wwj.sb.domain.Mp3Info;import com.wwj.sb.service.PlayerService;import com.wwj.sb.utils.ConstantUtil;import com.wwj.sb.utils.CustomDialog;import com.wwj.sb.utils.MediaUtil;/** * 2013/5/7 * 简、美音乐播放器 * @author wwj *  */public class HomeActivity extends Activity { private ListView mMusiclist; // 音乐列表 private List<Mp3Info> mp3Infos = null;// private SimpleAdapter mAdapter; // 简单适配器 MusicListAdapter listAdapter; //改为自定义列表适配器 private Button previousBtn; // 上一首 private Button repeatBtn; // 重复（单曲循环、全部循环） private Button playBtn; // 播放（播放、暂停） private Button shuffleBtn; // 随机播放 private Button nextBtn; // 下一首 private TextView musicTitle;//歌曲标题 private TextView musicDuration; //歌曲时间 private Button musicPlaying; //歌曲专辑 private ImageView musicAlbum; //专辑封面 private int repeatState;  //循环标识 private final int isCurrentRepeat = 1; // 单曲循环 private final int isAllRepeat = 2; // 全部循环 private final int isNoneRepeat = 3; // 无重复播放 private boolean isFirstTime = true;  private boolean isPlaying; // 正在播放 private boolean isPause; // 暂停 private boolean isNoneShuffle = true; // 顺序播放 private boolean isShuffle = false; // 随机播放   private int listPosition = 0; //标识列表位置 private HomeReceiver homeReceiver; //自定义的广播接收器 //一系列动作 public static final String UPDATE_ACTION = "com.wwj.action.UPDATE_ACTION";  //更新动作 public static final String CTL_ACTION = "com.wwj.action.CTL_ACTION";   //控制动作 public static final String MUSIC_CURRENT = "com.wwj.action.MUSIC_CURRENT";  //当前音乐改变动作 public static final String MUSIC_DURATION = "com.wwj.action.MUSIC_DURATION"; //音乐时长改变动作 public static final String REPEAT_ACTION = "com.wwj.action.REPEAT_ACTION";  //音乐重复改变动作 public static final String SHUFFLE_ACTION = "com.wwj.action.SHUFFLE_ACTION"; //音乐随机播放动作   private int currentTime; //当前时间 private int duration;  //时长 @Override public void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  setContentView(R.layout.home_activity_layout);  mMusiclist = (ListView) findViewById(R.id.music_list);  mMusiclist.setOnItemClickListener(new MusicListItemClickListener());  mMusiclist.setOnCreateContextMenuListener(new MusicListItemContextMenuListener());  mp3Infos = MediaUtil.getMp3Infos(HomeActivity.this); //获取歌曲对象集合//  setListAdpter(MediaUtil.getMusicMaps(mp3Infos)); //显示歌曲列表  listAdapter = new MusicListAdapter(this,mp3Infos);  mMusiclist.setAdapter(listAdapter);  findViewById();    //找到界面上的每一个控件  setViewOnclickListener(); //为一些控件设置监听器  repeatState = isNoneRepeat; // 初始状态为无重复播放状态      homeReceiver = new HomeReceiver();  // 创建IntentFilter  IntentFilter filter = new IntentFilter();  // 指定BroadcastReceiver监听的Action  filter.addAction(UPDATE_ACTION);  filter.addAction(MUSIC_CURRENT);  filter.addAction(MUSIC_DURATION);  filter.addAction(REPEAT_ACTION);  filter.addAction(SHUFFLE_ACTION);  // 注册BroadcastReceiver  registerReceiver(homeReceiver, filter);   } /**  * 从界面上根据id获取按钮  */ private void findViewById() {  previousBtn = (Button) findViewById(R.id.previous_music);  repeatBtn = (Button) findViewById(R.id.repeat_music);  playBtn = (Button) findViewById(R.id.play_music);  shuffleBtn = (Button) findViewById(R.id.shuffle_music);  nextBtn = (Button) findViewById(R.id.next_music);  musicTitle = (TextView) findViewById(R.id.music_title);  musicDuration = (TextView) findViewById(R.id.music_duration);  musicPlaying = (Button) findViewById(R.id.playing);  musicAlbum = (ImageView) findViewById(R.id.music_album); } /**  * 给每一个按钮设置监听器  */ private void setViewOnclickListener() {  ViewOnClickListener viewOnClickListener = new ViewOnClickListener();  previousBtn.setOnClickListener(viewOnClickListener);  repeatBtn.setOnClickListener(viewOnClickListener);  playBtn.setOnClickListener(viewOnClickListener);  shuffleBtn.setOnClickListener(viewOnClickListener);  nextBtn.setOnClickListener(viewOnClickListener);  musicPlaying.setOnClickListener(viewOnClickListener); } /**  * 控件的监听器  * @author Administrator  *  */ private class ViewOnClickListener implements OnClickListener {  Intent intent = new Intent();  @Override  public void onClick(View v) {   switch (v.getId()) {   case R.id.previous_music: // 上一首    playBtn.setBackgroundResource(R.drawable.play_selector);    isFirstTime = false;    isPlaying = true;    isPause = false;    previous();    break;   case R.id.repeat_music: // 重复播放    if (repeatState == isNoneRepeat) {     repeat_one();     shuffleBtn.setClickable(false);     repeatState = isCurrentRepeat;    } else if (repeatState == isCurrentRepeat) {     repeat_all();     shuffleBtn.setClickable(false);     repeatState = isAllRepeat;    } else if (repeatState == isAllRepeat) {     repeat_none();     shuffleBtn.setClickable(true);     repeatState = isNoneRepeat;    }    switch (repeatState) {    case isCurrentRepeat: // 单曲循环     repeatBtn       .setBackgroundResource(R.drawable.repeat_current_selector);     Toast.makeText(HomeActivity.this, R.string.repeat_current,       Toast.LENGTH_SHORT).show();     break;    case isAllRepeat: // 全部循环     repeatBtn       .setBackgroundResource(R.drawable.repeat_all_selector);     Toast.makeText(HomeActivity.this, R.string.repeat_all,       Toast.LENGTH_SHORT).show();     break;    case isNoneRepeat: // 无重复     repeatBtn       .setBackgroundResource(R.drawable.repeat_none_selector);     Toast.makeText(HomeActivity.this, R.string.repeat_none,       Toast.LENGTH_SHORT).show();     break;    }    break;   case R.id.play_music: // 播放音乐    if(isFirstTime) {     play();     isFirstTime = false;     isPlaying = true;     isPause = false;    } else {     if (isPlaying) {      playBtn.setBackgroundResource(R.drawable.pause_selector);      intent.setAction("com.wwj.media.MUSIC_SERVICE");      intent.putExtra("MSG", AppConstant.PlayerMsg.PAUSE_MSG);      startService(intent);      isPlaying = false;      isPause = true;           } else if (isPause) {      playBtn.setBackgroundResource(R.drawable.play_selector);      intent.setAction("com.wwj.media.MUSIC_SERVICE");      intent.putExtra("MSG", AppConstant.PlayerMsg.CONTINUE_MSG);      startService(intent);      isPause = false;      isPlaying = true;     }    }    break;   case R.id.shuffle_music: // 随机播放    if (isNoneShuffle) {     shuffleBtn       .setBackgroundResource(R.drawable.shuffle_selector);     Toast.makeText(HomeActivity.this, R.string.shuffle,       Toast.LENGTH_SHORT).show();     isNoneShuffle = false;     isShuffle = true;     shuffleMusic();     repeatBtn.setClickable(false);    } else if (isShuffle) {     shuffleBtn       .setBackgroundResource(R.drawable.shuffle_none_selector);     Toast.makeText(HomeActivity.this, R.string.shuffle_none,       Toast.LENGTH_SHORT).show();     isShuffle = false;     isNoneShuffle = true;     repeatBtn.setClickable(true);    }    break;   case R.id.next_music: // 下一首    playBtn.setBackgroundResource(R.drawable.play_selector);    isFirstTime = false;    isPlaying = true;    isPause = false;    next();    break;   case R.id.playing: //正在播放    Mp3Info mp3Info = mp3Infos.get(listPosition);    Intent intent = new Intent(HomeActivity.this, PlayerActivity.class);    intent.putExtra("title", mp3Info.getTitle());     intent.putExtra("url", mp3Info.getUrl());    intent.putExtra("artist", mp3Info.getArtist());    intent.putExtra("listPosition", listPosition);    intent.putExtra("currentTime", currentTime);    intent.putExtra("duration", duration);    intent.putExtra("MSG", AppConstant.PlayerMsg.PLAYING_MSG);    startActivity(intent);    break;   }  } } /**  * 列表点击监听器  * @author wwj  *  */ private class MusicListItemClickListener implements OnItemClickListener {  /**   * 点击列表播放音乐   */  @Override  public void onItemClick(AdapterView<?> parent, View view, int position,    long id) {   listPosition = position; //获取列表点击的位置   playMusic(listPosition); //播放音乐   } }  /**  * 上下文菜单显示监听器  * @author Administrator  *  */ public class MusicListItemContextMenuListener implements OnCreateContextMenuListener {  @Override  public void onCreateContextMenu(ContextMenu menu, View v,    ContextMenuInfo menuInfo) {   Vibrator vibrator = (Vibrator) getSystemService(Service.VIBRATOR_SERVICE);   vibrator.vibrate(50);   //长按振动   musicListItemDialog();  //长按后弹出的对话框   final AdapterView.AdapterContextMenuInfo menuInfo2 = (AdapterView.AdapterContextMenuInfo) menuInfo;   listPosition = menuInfo2.position; //点击列表的位置  } } /**  * 填充列表  *   * @param mp3Infos  */// public void setListAdpter(List<HashMap<String, String>> mp3list) {//  mAdapter = new SimpleAdapter(this, mp3list,//    R.layout.music_list_item_layout, new String[] {"title",//      "Artist", "duration" }, new int[] {R.id.music_title,//      R.id.music_Artist, R.id.music_duration });  mMusiclist.setAdapter(mAdapter);//  // }   /**  * 下一首歌曲  */ public void next() {  listPosition = listPosition + 1;  if(listPosition <= mp3Infos.size() - 1) {   Mp3Info mp3Info = mp3Infos.get(listPosition);   musicTitle.setText(mp3Info.getTitle());   Intent intent = new Intent();   intent.setAction("com.wwj.media.MUSIC_SERVICE");   intent.putExtra("listPosition", listPosition);   intent.putExtra("url", mp3Info.getUrl());   intent.putExtra("MSG", AppConstant.PlayerMsg.NEXT_MSG);   startService(intent);  } else {   listPosition = mp3Infos.size() - 1;   Toast.makeText(HomeActivity.this, "没有下一首了", Toast.LENGTH_SHORT).show();  } } /**  * 上一首歌曲  */ public void previous() {  listPosition = listPosition - 1;  if(listPosition >= 0) {   Mp3Info mp3Info = mp3Infos.get(listPosition);   musicTitle.setText(mp3Info.getTitle());   Intent intent = new Intent();   intent.setAction("com.wwj.media.MUSIC_SERVICE");   intent.putExtra("listPosition", listPosition);   intent.putExtra("url", mp3Info.getUrl());   intent.putExtra("MSG", AppConstant.PlayerMsg.PRIVIOUS_MSG);   startService(intent);  }else {   listPosition = 0;   Toast.makeText(HomeActivity.this, "没有上一首了", Toast.LENGTH_SHORT).show();  } } /**  * 播放音乐  */ public void play() {  playBtn.setBackgroundResource(R.drawable.play_selector);  Mp3Info mp3Info = mp3Infos.get(listPosition);  musicTitle.setText(mp3Info.getTitle());  Intent intent = new Intent();  intent.setAction("com.wwj.media.MUSIC_SERVICE");  intent.putExtra("listPosition", 0);  intent.putExtra("url", mp3Info.getUrl());  intent.putExtra("MSG", AppConstant.PlayerMsg.PLAY_MSG);  startService(intent); }  /**  * 单曲循环  */ public void repeat_one() {  Intent intent = new Intent(CTL_ACTION);  intent.putExtra("control", 1);  sendBroadcast(intent); }  /**  * 全部循环  */ public void repeat_all() {  Intent intent = new Intent(CTL_ACTION);  intent.putExtra("control", 2);  sendBroadcast(intent); } /**  * 顺序播放  */ public void repeat_none() {  Intent intent = new Intent(CTL_ACTION);  intent.putExtra("control", 3);  sendBroadcast(intent); }  /**  * 随机播放  */ public void shuffleMusic() {  Intent intent = new Intent(CTL_ACTION);  intent.putExtra("control", 4);  sendBroadcast(intent); } /**  * 自定义对话框  */ public void musicListItemDialog() {  String[] menuItems = new String[]{"播放音乐","设为铃声","查看详情"};  ListView menuList = new ListView(HomeActivity.this);  menuList.setCacheColorHint(Color.TRANSPARENT);  menuList.setDividerHeight(1);  menuList.setAdapter(new ArrayAdapter<String>(HomeActivity.this, R.layout.context_dialog_layout, R.id.dialogText, menuItems));  menuList.setLayoutParams(new LayoutParams(ConstantUtil.getScreen(HomeActivity.this)[0] / 2, LayoutParams.WRAP_CONTENT));      final CustomDialog customDialog = new CustomDialog.Builder(HomeActivity.this).setTitle(R.string.operation).setView(menuList).create();  customDialog.show();    menuList.setOnItemClickListener( new OnItemClickListener() {   @Override   public void onItemClick(AdapterView<?> parent, View view,     int position, long id) {    customDialog.cancel();    customDialog.dismiss();    if(position == 0){     playMusic(listPosition);    } else if(position == 1) {     setRing();    } else if(position == 2) {     showMusicInfo(listPosition);    }   }     }); }  /**  * 显示音乐详细信息  * @param position  */ private void showMusicInfo(int position) {  Mp3Info mp3Info = mp3Infos.get(position);  LayoutInflater inflater = (LayoutInflater) getSystemService(LAYOUT_INFLATER_SERVICE);  View view = inflater.inflate(R.layout.music_info_layout, null);  ((TextView) view.findViewById(R.id.tv_song_title)).setText(mp3Info.getTitle());  ((TextView) view.findViewById(R.id.tv_song_artist)).setText(mp3Info.getArtist());  ((TextView) view.findViewById(R.id.tv_song_album)).setText(mp3Info.getAlbum());  ((TextView) view.findViewById(R.id.tv_song_filepath)).setText(mp3Info.getUrl());  ((TextView) view.findViewById(R.id.tv_song_duration)).setText(MediaUtil.formatTime(mp3Info.getDuration()));  ((TextView) view.findViewById(R.id.tv_song_format)).setText(Contsant.getSuffix(mp3Info.getDisplayName()));  ((TextView) view.findViewById(R.id.tv_song_size)).setText(Contsant.formatByteToMB(mp3Info.getSize()) + "MB");  new CustomDialog.Builder(HomeActivity.this).setTitle("歌曲详细信息:").setNeutralButton("确定", null).setView(view).create().show(); } /**  * 设置铃声  */ protected void setRing() {  RadioGroup rg_ring = new RadioGroup(HomeActivity.this);  LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);  rg_ring.setLayoutParams(params);  //第一个单选按钮，来电铃声  final RadioButton rbtn_ringtones = new RadioButton(HomeActivity.this);  rbtn_ringtones.setText("来电铃声");  rg_ring.addView(rbtn_ringtones, params);  //第二个单选按钮，闹铃铃声  final RadioButton rbtn_alarms = new RadioButton(HomeActivity.this);  rbtn_alarms.setText("闹铃铃声");  rg_ring.addView(rbtn_alarms, params);  //第三个单选按钮，通知铃声  final RadioButton rbtn_notifications = new RadioButton(HomeActivity.this);  rbtn_notifications.setText("通知铃声");  rg_ring.addView(rbtn_notifications, params);  new CustomDialog.Builder(HomeActivity.this).setTitle("设置铃声").setView(rg_ring).setPositiveButton("确定", new DialogInterface.OnClickListener() {      @Override   public void onClick(DialogInterface dialog, int which) {    dialog.cancel();    dialog.dismiss();    if(rbtn_ringtones.isChecked()) {     try {      //设置来电铃声      setRingtone(listPosition);     } catch (Exception e) {      e.printStackTrace();     }    } else if(rbtn_alarms.isChecked()) {     try {      //设置闹铃      setAlarm(listPosition);     } catch (Exception e) {      e.printStackTrace();     }    } else if(rbtn_notifications.isChecked()) {     try {      //设置通知铃声      setNotifaction(listPosition);     } catch (Exception e) {      e.printStackTrace();     }    }   }  }).setNegativeButton("取消", null).show(); }  /**  * 设置提示音  * @param position  */ protected void setNotifaction(int position) {  Mp3Info mp3Info = mp3Infos.get(position);  File sdfile = new File(mp3Info.getUrl().substring(4));  ContentValues values = new ContentValues();        values.put(MediaStore.MediaColumns.DATA, sdfile.getAbsolutePath());        values.put(MediaStore.MediaColumns.TITLE, sdfile.getName());       values.put(MediaStore.MediaColumns.MIME_TYPE, "audio/*");         values.put(MediaStore.Audio.Media.IS_RINGTONE, true);        values.put(MediaStore.Audio.Media.IS_NOTIFICATION, false);        values.put(MediaStore.Audio.Media.IS_ALARM, false);        values.put(MediaStore.Audio.Media.IS_MUSIC, false);              Uri uri = MediaStore.Audio.Media.getContentUriForPath(sdfile.getAbsolutePath());       Uri newUri = this.getContentResolver().insert(uri, values);       RingtoneManager.setActualDefaultRingtoneUri(this, RingtoneManager.TYPE_NOTIFICATION, newUri);       Toast.makeText( getApplicationContext(),"设置通知铃声成功！", Toast.LENGTH_SHORT ).show(); } /**  * 设置闹铃  * @param position  */ protected void setAlarm(int position) {  Mp3Info mp3Info = mp3Infos.get(position);  File sdfile = new File(mp3Info.getUrl().substring(4));  ContentValues values = new ContentValues();        values.put(MediaStore.MediaColumns.DATA, sdfile.getAbsolutePath());        values.put(MediaStore.MediaColumns.TITLE, sdfile.getName());       values.put(MediaStore.MediaColumns.MIME_TYPE, "audio/*");         values.put(MediaStore.Audio.Media.IS_RINGTONE, true);        values.put(MediaStore.Audio.Media.IS_NOTIFICATION, false);        values.put(MediaStore.Audio.Media.IS_ALARM, false);        values.put(MediaStore.Audio.Media.IS_MUSIC, false);              Uri uri = MediaStore.Audio.Media.getContentUriForPath(sdfile.getAbsolutePath());       Uri newUri = this.getContentResolver().insert(uri, values);       RingtoneManager.setActualDefaultRingtoneUri(this, RingtoneManager.TYPE_ALARM, newUri);       Toast.makeText( getApplicationContext(),"设置闹钟铃声成功！", Toast.LENGTH_SHORT ).show(); } /**  * 设置来电铃声  * @param position  */ protected void setRingtone(int position) {  Mp3Info mp3Info = mp3Infos.get(position);  File sdfile = new File(mp3Info.getUrl().substring(4));  ContentValues values = new ContentValues();        values.put(MediaStore.MediaColumns.DATA, sdfile.getAbsolutePath());        values.put(MediaStore.MediaColumns.TITLE, sdfile.getName());       values.put(MediaStore.MediaColumns.MIME_TYPE, "audio/*");         values.put(MediaStore.Audio.Media.IS_RINGTONE, false);        values.put(MediaStore.Audio.Media.IS_NOTIFICATION, false);        values.put(MediaStore.Audio.Media.IS_ALARM, true);        values.put(MediaStore.Audio.Media.IS_MUSIC, false);              Uri uri = MediaStore.Audio.Media.getContentUriForPath(sdfile.getAbsolutePath());       Uri newUri = this.getContentResolver().insert(uri, values);       RingtoneManager.setActualDefaultRingtoneUri(this, RingtoneManager.TYPE_RINGTONE, newUri);       Toast.makeText( getApplicationContext(),"设置来电铃声成功！", Toast.LENGTH_SHORT ).show(); } /**  * 此方法通过传递列表点击位置来获取mp3Info对象  *   * @param listPosition  */ public void playMusic(int listPosition) {  if (mp3Infos != null) {   Mp3Info mp3Info = mp3Infos.get(listPosition);    musicTitle.setText(mp3Info.getTitle()); //这里显示标题   Bitmap bitmap = MediaUtil.getArtwork(this, mp3Info.getId(), mp3Info.getAlbumId(), true, true);//获取专辑位图对象，为小图   musicAlbum.setImageBitmap(bitmap); //这里显示专辑图片   Intent intent = new Intent(HomeActivity.this, PlayerActivity.class); //定义Intent对象，跳转到PlayerActivity   //添加一系列要传递的数据   intent.putExtra("title", mp3Info.getTitle());    intent.putExtra("url", mp3Info.getUrl());   intent.putExtra("artist", mp3Info.getArtist());   intent.putExtra("listPosition", listPosition);   intent.putExtra("currentTime", currentTime);   intent.putExtra("repeatState", repeatState);   intent.putExtra("shuffleState", isShuffle);   intent.putExtra("MSG", AppConstant.PlayerMsg.PLAY_MSG);   startActivity(intent);  } }  @Override protected void onStop() {  // TODO Auto-generated method stub  super.onStop(); }   @Override protected void onDestroy() {  // TODO Auto-generated method stub  super.onDestroy(); }  /**  * 按返回键弹出对话框确定退出  */ @Override public boolean onKeyDown(int keyCode, KeyEvent event) {  if (keyCode == KeyEvent.KEYCODE_BACK    && event.getAction() == KeyEvent.ACTION_DOWN) {   new AlertDialog.Builder(this)     .setIcon(R.drawable.ic_launcher)     .setTitle("退出")     .setMessage("您确定要退出？")     .setNegativeButton("取消", null)     .setPositiveButton("确定",       new DialogInterface.OnClickListener() {        @Override        public void onClick(DialogInterface dialog,          int which) {         finish();         Intent intent = new Intent(           HomeActivity.this,           PlayerService.class);         unregisterReceiver(homeReceiver);         stopService(intent); // 停止后台服务        }       }).show();  }  return super.onKeyDown(keyCode, event); }   //自定义的BroadcastReceiver，负责监听从Service传回来的广播 public class HomeReceiver extends BroadcastReceiver {  @Override  public void onReceive(Context context, Intent intent) {   String action = intent.getAction();    if(action.equals(MUSIC_CURRENT)){    //currentTime代表当前播放的时间    currentTime = intent.getIntExtra("currentTime", -1);    musicDuration.setText(MediaUtil.formatTime(currentTime));   } else if (action.equals(MUSIC_DURATION)) {    duration = intent.getIntExtra("duration", -1);   }   else if(action.equals(UPDATE_ACTION)) {    //获取Intent中的current消息，current代表当前正在播放的歌曲    listPosition = intent.getIntExtra("current", -1);    if(listPosition >= 0) {     musicTitle.setText(mp3Infos.get(listPosition).getTitle());    }   }else if(action.equals(REPEAT_ACTION)) {    repeatState = intent.getIntExtra("repeatState", -1);    switch (repeatState) {    case isCurrentRepeat: // 单曲循环     repeatBtn       .setBackgroundResource(R.drawable.repeat_current_selector);     shuffleBtn.setClickable(false);     break;    case isAllRepeat: // 全部循环     repeatBtn       .setBackgroundResource(R.drawable.repeat_all_selector);     shuffleBtn.setClickable(false);     break;    case isNoneRepeat: // 无重复     repeatBtn       .setBackgroundResource(R.drawable.repeat_none_selector);     shuffleBtn.setClickable(true);     break;    }   }   else if(action.equals(SHUFFLE_ACTION)) {    isShuffle = intent.getBooleanExtra("shuffleState", false);    if(isShuffle) {     isNoneShuffle = false;     shuffleBtn.setBackgroundResource(R.drawable.shuffle_selector);     repeatBtn.setClickable(false);    } else {     isNoneShuffle = true;     shuffleBtn.setBackgroundResource(R.drawable.shuffle_none_selector);     repeatBtn.setClickable(true);    }   }  }   }}

2016年补充：这个例子是笔者初学时做的一个Demo，还不是很完善，基于sdk也是比较旧，是基于Android 2.3版本的，现在Android已经更新迭代很多版本的了，无论是代码和sdk都已经不适用，大家学习这个demo的时候，了解开发的思路就行了，网上有很多优秀的开源播放器学习，音乐播放器作为入门练手的项目还是很不错的，这个系列的博文已经很久没更新，有很多错漏的地方，望大家见谅。