程序实现本地音乐文件的播放功能，显示播放歌曲的信息，显示本地歌词，从网络上获取歌词，摇一摇切歌，切换背景等功能！
1.要去实现播放音乐文件，因为程序关掉之后，音乐是不能停掉的，所以要在活动中去绑定服务，对音乐文件的操作都在服务中进行，
所以第一步新建工程之后将活动与新建的服务绑定，在这里给服务命名为MusicService，
public class MusicService extends Service {
private ArrayList<MyMusic> data=new ArrayList<>();//用来保存所有的音乐文件信息，MyMusic为实例类，一个MyMusic代表一个音乐文件
@Override
public IBinder onBind(Intent intent) {
return new LocalBinder();
}
@Override
public void unbindService(ServiceConnection conn) {
super.unbindService(conn);
}
public class LocalBinder extends Binder{
public MusicService getService(){
return MusicService.this;
}
/**
* 得到所有的音乐文件,这个方法去获得安卓手机里所有的音频文件，并保存在服务中
* @return
*/
private void getMusic(){
Cursor cursor = getContentResolver().query(
MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, null, null, null,
null
);
for (int i = 0; i < cursor.getCount(); i++) {
cursor.moveToNext();
//得到文件id
Long id = cursor.getLong(
cursor.getColumnIndex(MediaStore.Audio.Media._ID));
//得到作者
String author = cursor.getString(
cursor.getColumnIndex(MediaStore.Audio.Media.ARTIST));
//得到标题
String title = cursor.getString(cursor.getColumnIndex
(MediaStore.Audio.Media.TITLE));
//得到路径，播放音乐时候需要用到，必不可少
String url = cursor.getString(cursor.getColumnIndex
(MediaStore.Audio.Media.DATA));
//得到播放时间
Long time = cursor.getLong(
cursor.getColumnIndex(MediaStore.Audio.Media.DURATION));
//得到大小
Long size = cursor.getLong(
cursor.getColumnIndex(MediaStore.Audio.Media.SIZE));
//是否为音乐
int isMusic = cursor.getInt(cursor
.getColumnIndex(MediaStore.Audio.Media.IS_MUSIC));
if (isMusic != 0&& time > 100000&&size>3500000) {
MyMusic myMusic = new MyMusic(url, title, author, size, time, id);
//将音乐添加到ArrayList中ArrayList用来保存音乐文件信息
data.add(myMusic);
}
}
cursor.close();
}
}
}
服务中这么写，只是第一步，后续还有更多的功能需要去添加，接下来在活动去绑定服务，获取服务中的音乐数据
private MusicAdapter adapter;
private ArrayList<MyMusic> data=new ArrayList<>();
private ServiceConnection conn= new ServiceConnection() {
@Override
public void onServiceConnected(ComponentName name, IBinder service) {
//绑定服务后开始运行，记得打括号
musicService=((MusicService.LocalBinder)service).getService();
//得到数据
data=musicService.getData();
adapter = new MusicAdapter(ListActivity.this, data,height);
listView_music.setAdapter(adapter);
textview_title.setText(musicService.gettitle());
if(musicService.isRun()){
imageButton_pause.setImageDrawable(getResources().getDrawable(R.drawable.play));
}
}
@Override
public void onServiceDisconnected(ComponentName name) {
musicService=null;
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_list);
height=getWindowManager().getDefaultDisplay().getHeight();
listView_music = (ListView) findViewById(R.id.listView);
seekBar = (SeekBar) findViewById(R.id.seekBar);
imageButton_pause = (ImageButton) findViewById(R.id.imageButton_pause);
imageButton_next = (ImageButton) findViewById(R.id.imageButton_next);
imageButton_special = (ImageButton) findViewById(R.id.imageButton_special);
textview_title = (TextView) findViewById(R.id.textView_title);
listView_left= (ListView) findViewById(R.id.draw_listview);
line_list= (LinearLayout) findViewById(R.id.line_list);
//初始化按钮
imageButton_special.setImageDrawable(getResources().getDrawable(R.drawable.special));
imageButton_pause.setImageDrawable(getResources().getDrawable(R.drawable.pause));
imageButton_next.setImageDrawable(getResources().getDrawable(R.drawable.next));
textview_title.setText("");
intent=new Intent(this,MusicService.class);
startService(intent);
bindService(intent, conn, BIND_AUTO_CREATE);
adpater_left=new Adpater_left(this);
listView_left.setAdapter(adpater_left);
listView_left.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
switch (position) {
case 0:
//视频播放
Intent intent_video=new Intent(ListActivity.this,VideoListActivity.class);
startActivity(intent_video);
break;
case 1:
break;
case 2:
Intent intent_set = new Intent(ListActivity.this, SetActivity.class);
startActivity(intent_set);
break;
case 3:
Intent intent_bg = new Intent(ListActivity.this, BG_Activity.class);
startActivity(intent_bg);
break;
case 4:
ListActivity.this.finish();
musicService.exit();
stopService(intent);
break;
}
}
});
seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
int px, px1, px2;
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
px1 = seekBar.getProgress();
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
px2 = seekBar.getProgress();
if (px1 == px2) {
musicService.seek(px2);
p = px2;
musicService.setProgress(p);
} else if (px - 500 < px1 && px1 < px1 + 500) {
musicService.seek(px2);
p = px2;
musicService.setProgress(p);
}
imageButton_pause.setImageDrawable(getResources().getDrawable(R.drawable.play));
}
});
listView_music.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
//播放当前曲目
musicService.play(position);
seek();
musicService.startTimer();
textview_title.setText(musicService.gettitle());
imageButton_pause.setImageDrawable(getResources().getDrawable(R.drawable.play));
}
});
listView_music.setChoiceMode(ListView.CHOICE_MODE_SINGLE);
registerForContextMenu(listView_music);
}