Android在Surfaceview中播放视频NullPointerException

我尝试在Surfaceview中播放视频。我使用Fragment（扩展Fragment），我有NullPointerException。我不知道我在做什么错。第一次使用Activity并在Activity项目中运行完美，但是我使用Fragment却出现错误

这是我的资料

public class Layout1 extends Fragment implements OnBufferingUpdateListener,
    OnCompletionListener, OnPreparedListener, OnVideoSizeChangedListener,
    SurfaceHolder.Callback, MediaPlayerControl {
MediaPlayer mMediaPlayer;
SurfaceView mSurfaceView;
SurfaceHolder holder;
String video = "http://www.pocketjourney.com/downloads/pj/video/famous.3gp";
MediaController mcontroller;
Handler handler;
String videoUrl;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_layout1, null);

    SurfaceView v = (SurfaceView) view
            .findViewById(R.id.screen_tutorial_video_surface);
    handler = new Handler();
    holder = v.getHolder();
    holder.addCallback(this);
    playVideo();
    return view;
}

private void playVideo() {
    try {
        mcontroller = new MediaController(getActivity());
        mcontroller.setVisibility(View.INVISIBLE);

        mMediaPlayer = MediaPlayer.create(getActivity(), Uri.parse(video));
        mMediaPlayer.setOnBufferingUpdateListener(this);
        mMediaPlayer.setOnCompletionListener(this);
        mMediaPlayer.setOnPreparedListener(this);

        mMediaPlayer.setScreenOnWhilePlaying(true);
        mMediaPlayer.setOnVideoSizeChangedListener(this);

        mMediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);

    } catch (Exception e) {
        e.printStackTrace();
    }
}

@Override
public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {

}

@Override
public void surfaceCreated(SurfaceHolder arg0) {

    mMediaPlayer.setDisplay(holder);
    try {
        // progressDialog.dismiss();
        mMediaPlayer.start();

    } catch (IllegalStateException e) {
        e.printStackTrace();
    }
}

@Override
public void surfaceDestroyed(SurfaceHolder arg0) {

}

@Override
public void onVideoSizeChanged(MediaPlayer mp, int width, int height) {
    // TODO Auto-generated method stub
}

@Override
public void onPrepared(MediaPlayer mp) {

    // mcontroller.setMediaPlayer(this);
    // mcontroller
    // .setAnchorView(findViewById(R.id.screen_tutorial_video_surface));
    // mcontroller.setEnabled(true);
    //
    // handler.post(new Runnable() {
    // public void run() {
    // mcontroller.show();
    // }
    // });
}

@Override
public void onCompletion(MediaPlayer mp) {

}

@Override
public void onBufferingUpdate(MediaPlayer mp, int percent) {

}

public void start() {
    mMediaPlayer.start();
}

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

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

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

public void seekTo(int i) {
    mMediaPlayer.seekTo(1);
}

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

public int getBufferPercentage() {
    return 0;
}

public boolean canPause() {
    return true;
}

public boolean canSeekBackward() {
    return true;
}

public boolean canSeekForward() {
    return true;
}
}

错误记录