Mediaplayer 当前位置始终为零

Question

我正在构建一个简单的音乐应用程序。

无论我尝试什么，我都无法停止一首歌曲以播放一首新歌。我试过一起停止、释放、停止和释放；我创建了一个服务；我什至尝试使用当前位置来获取 MP3 的位置，如果位置大于 1，则考虑播放它。
但是没有任何效果，我想弄清楚这一点我很生气。
我为此工作了 5 天，但我所做的一切都失败了。

我将不胜感激任何建议和明确的解决方案。
我是一个菜鸟，我正在努力解决自己的问题，但这个问题让我很难过。

import android.app.Service;
import android.content.Intent;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.os.IBinder;
import android.support.annotation.Nullable;
import android.util.Log;

import java.io.IOException;

public class MyService extends Service {

@Nullable
@Override
public IBinder onBind(Intent intent) {
    return null;
}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    MediaPlayer mediaplayer;
    mediaplayer = new MediaPlayer();
    mediaplayer.setAudioStreamType(AudioManager.STREAM_MUSIC);

    String extRec = intent.getExtras().getString("extRec");
    Log.d("My Service", "Received extra: " + extRec);

    if (mediaplayer.isPlaying()){

        Log.d("My Service is playing ", "yes");

    }
    else {
        Log.d("My Service is playing ", "no");
    }

    //mediaplayer.stop();
    //mediaplayer.release();

    try {

        final String AudioURL = extRec;
        Log.d("My Service audioURL ", AudioURL);

        mediaplayer.setDataSource(AudioURL);
        mediaplayer.prepare();

        Log.d("My Service", "position: " + mediaplayer.getCurrentPosition() );
        mediaplayer.start();

    } 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();
    }
    return START_STICKY;
}
}

Answer 1

用户媒体控制器将为您提供帮助：

public class AudioPlayer extends Activity implements OnPreparedListener, MediaController.MediaPlayerControl{
  private static final String TAG = "AudioPlayer";

  public static final String AUDIO_FILE_NAME = "audioFileName";

  private MediaPlayer mediaPlayer;
  private MediaController mediaController;
  private String audioFile;

  private Handler handler = new Handler();

  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.audio_player);

    audioFile = this.getIntent().getStringExtra(AUDIO_FILE_NAME);
    ((TextView)findViewById(R.id.now_playing_text)).setText(audioFile);

    mediaPlayer = new MediaPlayer();
    mediaPlayer.setOnPreparedListener(this);

    mediaController = new MediaController(this);

    try {
      mediaPlayer.setDataSource(audioFile);
      mediaPlayer.prepare();
      mediaPlayer.start();
    } catch (IOException e) {
      Log.e(TAG, "Could not open file " + audioFile + " for playback.", e);
    }

  }

  @Override
  protected void onStop() {
    super.onStop();
    mediaController.hide();
    mediaPlayer.stop();
    mediaPlayer.release();
  }

  @Override
  public boolean onTouchEvent(MotionEvent event) {
    //the MediaController will hide after 3 seconds - tap the screen to make it appear again
    mediaController.show();
    return false;
  }

  //--MediaPlayerControl methods----------------------------------------------------
  public void start() {
    mediaPlayer.start();
  }

  public void pause() {
    mediaPlayer.pause();
  }

  public int getDuration() {
    return mediaPlayer.getDuration();
  }

  public int getCurrentPosition() {
    return mediaPlayer.getCurrentPosition();
  }

  public void seekTo(int i) {
    mediaPlayer.seekTo(i);
  }

  public boolean isPlaying() {
    return mediaPlayer.isPlaying();
  }

  public int getBufferPercentage() {
    return 0;
  }

  public boolean canPause() {
    return true;
  }

  public boolean canSeekBackward() {
    return true;
  }

  public boolean canSeekForward() {
    return true;
  }
  //--------------------------------------------------------------------------------

  public void onPrepared(MediaPlayer mediaPlayer) {
    Log.d(TAG, "onPrepared");
    mediaController.setMediaPlayer(this);
    mediaController.setAnchorView(findViewById(R.id.main_audio_view));

    handler.post(new Runnable() {
      public void run() {
        mediaController.setEnabled(true);
        mediaController.show();
      }
    });
  }
}

要获得良好的播放功能，请使用Exoplayer