我的Android应用程序崩溃录制视频？

Question

使用以下代码录制视频并使用videoView播放。

static final int VIDEO_CAPTURE = 101;
    File mediaFile;
    VideoView videoView;

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        Uri videoUri = Uri.fromFile(mediaFile);
        videoView.setVideoURI(videoUri);
        videoView.requestFocus();
        videoView.start();
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_video_rec);
        videoView=(VideoView)findViewById(R.id.videoView);
        mediaFile = new File(Environment.getExternalStorageDirectory().getAbsolutePath() + "/myvideo.mp4");
        Intent intent = new Intent(MediaStore.ACTION_VIDEO_CAPTURE);
        Uri videoUri = Uri.fromFile(mediaFile);
        intent.putExtra(MediaStore.EXTRA_OUTPUT, videoUri);
        startActivityForResult(intent, VIDEO_CAPTURE);
    }

但是当我开始活动相机打开但是当我开始录制我的应用程序崩溃时。有什么问题？