前面有一個簡單的音樂播放器，能夠簡單的播放歌曲，這裏實現稍微完善的播放器。
音樂播放器
播放服務
- 播放音頻的代碼應該運行在服務中，定義一個播放服務MusicService
-
服務裏定義play、stop、pause、continuePlay等方法
private void play() { // TODO Auto-generated method stub player.reset(); try { player.setDataSource("sdcard/bzj.mp3"); player.prepare(); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } player.start(); } private void pause() { player.pause(); } private void stop() { player.stop(); } private void continuePlay() { player.start(); } - 把這幾個方法抽取成一個接口MusicInterface
- 定義一箇中間人類，繼承Binder，實現MusicInterface
-
先start啓動MusicService，再bind
Intent intent = new Intent(this, MusicService.class); startService(intent); bindService(intent, conn, BIND_AUTO_CREATE);
根據播放進度設置進度條
-
獲取當前的播放時間和當前音頻的最長時間
int currentPosition = player.getCurrentPosition(); int duration = player.getDuration(); - 播放進度需要不停的獲取，不停的刷新進度條，使用計時器每500毫秒獲取一次播放進度
-
發消息至Handler，把播放進度放進Message對象中，在Handler中更新SeekBar的進度
Timer timer = new Timer(); timer.schedule(new TimerTask() { @Override public void run() { int currentPosition = player.getCurrentPosition(); int duration = player.getDuration(); Message msg = Message.obtain(); //把播放進度存入Message中 Bundle data = new Bundle(); data.putInt("currentPosition", currentPosition); data.putInt("duration", duration); msg.setData(data); MainActivity.handler.sendMessage(msg); } }, 5, 500); -
在Activity中定義Handler
static Handler handler = new Handler(){ public void handleMessage(android.os.Message msg) { //取出消息攜帶的數據 Bundle data = msg.getData(); int currentPosition = data.getInt("currentPosition"); int duration = data.getInt("duration"); //設置播放進度 sb.setMax(duration); sb.setProgress(currentPosition); }; };
拖動進度條改變播放進度
//給sb設置一個拖動偵聽
sb.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
//停止拖動時調用
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
int progress = seekBar.getProgress();
mi.seekTo(progress);
}
//開始拖動時調用
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
//拖動的時候不斷調用
@Override
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
// TODO Auto-generated method stub
}
});
中間人接口
public interface MusicInterface { void play(); void pause(); void continuePlay(); void seekTo(int progress);}
服務
public class MusicService extends Service { MediaPlayer player; private Timer timer; @Override public IBinder onBind(Intent intent) { // TODO Auto-generated method stub return new MusicController(); } class MusicController extends Binder implements MusicInterface{ @Override public void play() { MusicService.this.play(); } @Override public void pause() { MusicService.this.pause(); } @Override public void continuePlay() { MusicService.this.continuePlay(); } @Override public void seekTo(int progress) { MusicService.this.seekTo(progress); } } @Override public void onCreate() { // TODO Auto-generated method stub super.onCreate(); player = new MediaPlayer(); } @Override public void onDestroy() { // TODO Auto-generated method stub super.onDestroy(); //停止播放 player.stop(); //釋放佔用的資源，此時player對象已經廢掉了 player.release(); player = null; if(timer != null){ timer.cancel(); timer = null; } } //播放音樂 public void play(){ //重置 player.reset(); try { //加載多媒體文件 player.setDataSource("sdcard/zxmzf.mp3");// player.setDataSource("http://192.168.13.119:8080/bzj.mp3");// player.prepare(); //同步 player.prepareAsync(); //異步// player.start(); player.setOnPreparedListener(new OnPreparedListener() { //準備完畢時，此方法調用 @Override public void onPrepared(MediaPlayer mp) { player.start(); addTimer(); } }); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } //繼續播放 public void continuePlay(){ player.start(); } //暫停播放 public void pause(){ player.pause(); } public void seekTo(int progress){ player.seekTo(progress); } public void addTimer(){ if(timer == null){ timer = new Timer(); timer.schedule(new TimerTask() { @Override public void run() { //獲取歌曲總時長 int duration = player.getDuration(); //獲取歌曲當前播放進度 int currentPosition= player.getCurrentPosition(); Message msg = MainActivity.handler.obtainMessage(); //把進度封裝至消息對象中 Bundle bundle = new Bundle(); bundle.putInt("duration", duration); bundle.putInt("currentPosition", currentPosition); msg.setData(bundle); MainActivity.handler.sendMessage(msg); } //開始計時任務後的5毫秒，第一次執行run方法，以後每500毫秒執行一次 }, 5, 500); } }}
Activity
public class MainActivity extends Activity { static Handler handler = new Handler(){ public void handleMessage(android.os.Message msg) { Bundle bundle = msg.getData(); int duration = bundle.getInt("duration"); int currentPostition = bundle.getInt("currentPosition"); //刷新進度條的進度 sb.setMax(duration); sb.setProgress(currentPostition); } }; MusicInterface mi; private MyserviceConn conn; private Intent intent; private static SeekBar sb; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); sb = (SeekBar) findViewById(R.id.sb); sb.setOnSeekBarChangeListener(new OnSeekBarChangeListener() { @Override public void onStopTrackingTouch(SeekBar seekBar) { //根據拖動的進度改變音樂播放進度 int progress = seekBar.getProgress(); //改變播放進度 mi.seekTo(progress); } @Override public void onStartTrackingTouch(SeekBar seekBar) { } @Override public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) { } }); intent = new Intent(this, MusicService.class); startService(intent); conn = new MyserviceConn(); bindService(intent, conn, BIND_AUTO_CREATE); } class MyserviceConn implements ServiceConnection{ @Override public void onServiceConnected(ComponentName name, IBinder service) { mi = (MusicInterface) service; } @Override public void onServiceDisconnected(ComponentName name) { // TODO Auto-generated method stub } } public void play(View v){ mi.play(); } public void continuePlay(View v){ mi.continuePlay(); } public void pause(View v){ mi.pause(); } public void exit(View v){ unbindService(conn); stopService(intent); } }