创建service
当启动一个Service的时候，会调用该Service中的onCreate()和onStartCommand()方法。
当再次start Service，这次只有onStartCommand()方法执行了，onCreate()方法并没有执行，为什么会这样呢？
这是由于onCreate()方法只会在Service第一次被创建的时候调用，如果当前Service已经被创建过了，不管怎样调用startService()方法，onCreate()方法都不会再执行。
所以，我们可以通过startIntent.putExtra(“String”, String);传递Action开启服务。
@Overridepublic int onStartCommand(Intent intent, int flags, int startId) {acquireWakeLock();if (intent!=null){switch (intent.getStringExtra("action")) {case START:MusicUtil.getInstance().prePlayOrNextPlay();musicNotifi.onUpdataMusicNotifi(MusicUtil.getInstance().getNewSongInfo(),MusicUtil.getInstance().isPlaying());sendBroadcast(intent2);break;case COMPLETE:MusicUtil.getInstance().prePlayOrNextPlay();musicNotifi.onUpdataMusicNotifi(MusicUtil.getInstance().getNewSongInfo(),MusicUtil.getInstance().isPlaying());sendBroadcast(intent2);break;case PLAYORPAUSE:MusicUtil.getInstance().playOrPause();musicNotifi.onUpdataMusicNotifi(MusicUtil.getInstance().getNewSongInfo(),MusicUtil.getInstance().isPlaying());sendBroadcast(intent2);break;case PREVIOUSMUSIC:MusicUtil.getInstance().prePlayOrNextPlay();musicNotifi.onUpdataMusicNotifi(MusicUtil.getInstance().getNewSongInfo(),MusicUtil.getInstance().isPlaying());sendBroadcast(intent2);break;case NEXTMUSIC:MusicUtil.getInstance().prePlayOrNextPlay();musicNotifi.onUpdataMusicNotifi(MusicUtil.getInstance().getNewSongInfo(),MusicUtil.getInstance().isPlaying());sendBroadcast(intent2);break;}}
MusicUtil中添加方法
public class MusicUtil{private int currentSongPosition = -1;private boolean isPrepare = false;private static MediaPlayer mediaPlayer;private static MusicUtil musicUtils;private List<Song> list;//本地歌曲数据/*** 顺序播放*/public static final int TYPE_ORDER = 4212;/*** 播放模式*/private int pattern = TYPE_ORDER;/*** 随机播放*/public static final int TYPE_RANDOM = 4313;/*** 单曲循环*/public static final int TYPE_SINGLE = 4414;public Song song;public int getPattern(){return pattern;}//获得当前播放模式public void setPatten(int i) {if (i == TYPE_SINGLE) {this.pattern = TYPE_SINGLE;}if (i == TYPE_ORDER) {this.pattern = TYPE_ORDER;Log.i("pat8",""+pattern);}if (i == TYPE_RANDOM) {this.pattern = TYPE_RANDOM;}}//设置当前播放模式public int getCurrentSongPosition(){return currentSongPosition;}//获得当前播放歌曲的下标//播放还是暂停public void playOrPause() {if (mediaPlayer == null) {playMusic(list.get(0));return;}if (mediaPlayer.isPlaying()) {mediaPlayer.pause();} else {mediaPlayer.start();}}//释放资源public void clean() {mediaPlayer.stop();mediaPlayer.release();}//根据播放模式 将上一首歌歌曲改成当前播放歌曲下标public void pre(){preSongPosition = currentSongPosition;if (pattern == TYPE_ORDER||pattern == TYPE_SINGLE) {preSongPosition = currentSongPosition;if (currentSongPosition == 0){currentSongPosition=MusicUtil.getInstance().getListCount()-1;}else{currentSongPosition = currentSongPosition -1;}}if (pattern == TYPE_RANDOM) {currentSongPosition = new Random().nextInt(MusicUtil.getInstance().getListCount()-1);}Log.i("song1",""+list.get(currentSongPosition).getSinger());}//播放public void prePlayOrNextPlay(){playMusic(list.get(currentSongPosition));}//将新的歌曲信息返回 用于界面数据的更新public Song getNewSongInfo(){if(list.get(currentSongPosition)==null)Log.d(TAG, "getNewSongInfo: "+"孔");return list.get(currentSongPosition);}public Song getPreSongInfo(){if(list.get(currentSongPosition)==null)Log.d(TAG, "getNewSongInfo: "+"孔");return list.get(preSongPosition);}// 下一首，和Pre(）相对应public void next(){preSongPosition = currentSongPosition;if (pattern == TYPE_ORDER||pattern == TYPE_SINGLE) {if (currentSongPosition == MusicUtil.getInstance().getListCount()-1){currentSongPosition = 0;}else{currentSongPosition=currentSongPosition+1;}}if (pattern == TYPE_RANDOM) {currentSongPosition = new Random().nextInt(MusicUtil.getInstance().getListCount()-1);}}//完成当前歌曲后执行下一首 与pre不同的是 若为单曲循环 则当前歌曲不变public void comNext(){preSongPosition = currentSongPosition;if (pattern == TYPE_SINGLE){return;}else if (pattern == TYPE_ORDER) {if (currentSongPosition == MusicUtil.getInstance().getListCount()-1){currentSongPosition = 0;}else{currentSongPosition=currentSongPosition+1;}}else if (pattern == TYPE_RANDOM) {currentSongPosition = new Random().nextInt(MusicUtil.getInstance().getListCount()-1);}}//获得mediaPlayer，方便后面调用其中方法时候使用public MediaPlayer getMediaPlayer(){return mediaPlayer;}}
在Activity中开启服务。
开始播放 写在onCreate中（）
if (song.getPosition() != MusicUtil.getInstance().getCurrentSongPosition()) {LrcCount = 1;MusicUtil.getInstance().setCurrentSongPosition(song.getPosition());Intent startIntent6 = new Intent(this, MusicService.class);startIntent6.putExtra("action", MusicService.START);startService(startIntent6);isplay = true;} else {isplay = MusicUtil.getInstance().isPlaying();}
切换歌曲类似于开始播放，也是通过传递Action。
这里要注意，我是先改变Music Util里面的currentSongPosition值，再通过开启服务播放音乐，为什么不都放在服务里呢？
我不是故意多写的嘛~那是因为开启服务会有异步问题~我们会发现界面信息是之前那首~所以宝宝们写的时候要注意了！喵~
@OnClick({R.id.iv_back, R.id.iv_mode, R.id.iv_prev, R.id.iv_play, R.id.iv_next})public void onViewClicked(View view) {switch (view.getId()) {case R.id.iv_back:break;case R.id.iv_prev:if (!isplay){isplay=true;ivPlay.setImageResource(R.drawable.play_btn_pause_selector);}MusicUtil.getInstance().pre();changInfo();Intent startIntent2 = new Intent(this, MusicService.class);startIntent2.putExtra("action",MusicService.PREVIOUSMUSIC);startService(startIntent2);break;case R.id.iv_play:Intent startIntent1 = new Intent(this, MusicService.class);startIntent1.putExtra("action",MusicService.PLAYORPAUSE);startService(startIntent1);if (isplay){ivPlay.setImageResource(R.drawable.play_btn_play_selector);isplay =false;}else{isplay =true;ivPlay.setImageResource(R.drawable.play_btn_pause_selector);}break;case R.id.iv_next:MusicUtil.getInstance().next();changInfo();if (!isplay){isplay=true;ivPlay.setImageResource(R.drawable.play_btn_pause_selector);}Intent startIntent3 = new Intent(this, MusicService.class);startIntent3.putExtra("action",MusicService.NEXTMUSIC);startService(startIntent3);break;}}
给Mediaplay设置完成监听。
MusicUtil.getInstance().getMediaPlayer().setOnCompletionListener(new MediaPlayer.OnCompletionListener() {@Overridepublic void onCompletion(MediaPlayer mediaPlayer) {MusicUtil.getInstance().comNext();changInfo();//改变当前页面的信息Intent startIntent4 = new Intent(MusicActivity.this, MusicService.class);startIntent4.putExtra("action", PLETE);startService(startIntent4);}});
更改界面信息
public void changInfo(){Song newSong = MusicUtil.getInstance().getNewSongInfo();if(newSong ==null)return;Log.i("song2",""+newSong.getSinger());tvTitle.setText(newSong.getSong());tvSinger.setText(newSong.getSinger());}
更换播放模式
设置全局变量
private int mode = MusicUtil.TYPE_ORDER ;
判断图标显示
设置播放模式为上次退出时候一样if (mode != MusicUtil.getInstance().getPattern()) {mode = MusicUtil.getInstance().getPattern();}// 根据模式设置相对应显示的图标if (mode == MusicUtil.TYPE_ORDER) {ivMode.setImageResource(R.drawable.play_btn_loop_selector);} else if (mode == TYPE_SINGLE) {ivMode.setImageResource(R.drawable.play_btn_one_selector);} else {ivMode.setImageResource(R.drawable.play_btn_shuffle_selector);}}
点击事件
case R.id.iv_mode:if (mode == MusicUtil.TYPE_ORDER){Toast.makeText(this, "咦，已经切换为随机模式n(*≧▽≦*)n", Toast.LENGTH_SHORT).show();mode = MusicUtil.TYPE_RANDOM;ivMode.setImageResource(R.drawable.play_btn_shuffle_selector);MusicUtil.getInstance().setPatten(MusicUtil.TYPE_RANDOM);}else if(mode == MusicUtil.TYPE_RANDOM){Log.i("pat2",""+mode);Toast.makeText(this, "已经准备好单曲循环O(∩_∩)O", Toast.LENGTH_SHORT).show();this.mode = TYPE_SINGLE;ivMode.setImageResource(R.drawable.play_btn_one_selector);MusicUtil.getInstance().setPatten(TYPE_SINGLE);Log.i("pat4",""+mode);}else if (mode == TYPE_SINGLE){Log.i("pat5",""+mode);Toast.makeText(this, "那就按顺序播放吧n(*≧▽≦*)n", Toast.LENGTH_SHORT).show();this.mode = MusicUtil.TYPE_ORDER;ivMode.setImageResource(R.drawable.play_btn_loop_selector);MusicUtil.getInstance().setPatten(MusicUtil.TYPE_ORDER);Log.i("pat6",""+mode);}break;
