Question

当我尝试完成媒体播放器活动时（仅在我播放时），我得到了一个例外。代码：

完成按钮：

ImageView imageAllBack = (ImageView)this.findViewById(R.id.imageAllBack);
        imageAllBack.setOnClickListener(new OnClickListener() {
            public void onClick(View v) {                   

                //mediaPlayer.stop();
                if(mediaPlayer != null)
                {
                    mediaPlayer.stop();
                    mediaPlayer.release();
                }

                 finish();

            }
          });

MediaPlayer活动：

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

  @Override
  public boolean onTouchEvent(MotionEvent event) {
    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) {
    mediaController.setMediaPlayer(this);
    mediaController.setAnchorView(findViewById(R.id.main_audio_view));

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

  public class MyMediaController extends MediaController {

      public MyMediaController(Context context) {
        super(context);
        // TODO Auto-generated constructor stub
    }

    @Override
          public void hide() {
              // Do Nothing to keep the show the controller all times

          }

      }

例外：

02-21 21:03:33.829: E/AndroidRuntime(8889): FATAL EXCEPTION: main
02-21 21:03:33.829: E/AndroidRuntime(8889): java.lang.IllegalStateException
02-21 21:03:33.829: E/AndroidRuntime(8889):     at android.media.MediaPlayer.isPlaying(Native Method)
02-21 21:03:33.829: E/AndroidRuntime(8889):     at rce.android.naturalocal.NaturaPlayer.isPlaying(NaturaPlayer.java:126)
02-21 21:03:33.829: E/AndroidRuntime(8889):     at rce.android.naturalocal.NaturaPlayer.getCurrentPosition(NaturaPlayer.java:115)
02-21 21:03:33.829: E/AndroidRuntime(8889):     at android.widget.MediaController.setProgress(MediaController.java:436)
02-21 21:03:33.829: E/AndroidRuntime(8889):     at android.widget.MediaController.access$500(MediaController.java:74)
02-21 21:03:33.829: E/AndroidRuntime(8889):     at android.widget.MediaController$3.handleMessage(MediaController.java:407)
02-21 21:03:33.829: E/AndroidRuntime(8889):     at android.os.Handler.dispatchMessage(Handler.java:99)
02-21 21:03:33.829: E/AndroidRuntime(8889):     at android.os.Looper.loop(Looper.java:137)
02-21 21:03:33.829: E/AndroidRuntime(8889):     at android.app.ActivityThread.main(ActivityThread.java:4441)
02-21 21:03:33.829: E/AndroidRuntime(8889):     at java.lang.reflect.Method.invokeNative(Native Method)
02-21 21:03:33.829: E/AndroidRuntime(8889):     at java.lang.reflect.Method.invoke(Method.java:511)
02-21 21:03:33.829: E/AndroidRuntime(8889):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
02-21 21:03:33.829: E/AndroidRuntime(8889):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
02-21 21:03:33.829: E/AndroidRuntime(8889):     at dalvik.system.NativeStart.main(Native Method)

Answer 1

在调用stop之前，你必须检查mediaPlayer是否实际运行，否则你将得到 IllegalStateException 。当你对已发布的MediaPlayer对象做任何事情时，你也会得到它。你的代码应该是：

onClick(View view) {
  if(mediaPlayer != null) {
    if mediaPlayer.isPlaying()) {
            mediaPlayer.stop();
        }
        mediaPlayer.release();
        mediaPlayer = null;
    }
}   

protected void onStop() {
    super.onStop();
    if(mediaPlayer != null) {
        if (mediaPlayer.isPlaying()) {
            mediaPlayer.stop();
        }
        mediaPlayer.release();
        mediaPlayer = null;
    }
}

请查看MediaPlayer文档：Doc

完成活动时的MediaPlayer异常

1 个答案: