How to force to click X(close, back button) in Displaymode (3) of VrVideoView?

I am making a VR Android application using VrVideoView. I want to force "close(X, back button)" to be clicked after the video is played. That is, I want to return to MainActivity after the video finishes. Below is the codes I've tried. However, I did not go back to MainActivity after the video was finished. If you know how, please let me know.

1.

videoWidgetView.pauseVideo();
videoWidgetView.seekTo(0);
videoWidgetView.shutdown();

2.

videoWidgetView.pauseVideo();
videoWidgetView.seekTo(0);
finishActivity(0);

3.

videoWidgetView.pauseVideo();
videoWidgetView.seekTo(0);
findViewById(R.id.ui_back_button).performClick();

4.

videoWidgetView.pauseVideo();
videoWidgetView.seekTo(0);
Field f;

try {

     f =videoWidgetView.getClass().getSuperclass().getDeclaredField("vrUiLayer");
     f.setAccessible(true);
     UiLayer vrLayer = (UiLayer) f.get(videoWidgetView);

     vrLayer.getView().findViewById(R.id.ui_back_button).performClick();

} 
catch (NoSuchFieldException e) {
      e.printStackTrace();
} 
catch (IllegalAccessException e) {
   e.printStackTrace();
}

Just override OnDestroy method and add these lines into it:

@Override
protected void onDestroy() {
    videoWidgetView.shutdown();
    super.onDestroy();
}

Then call onDestroy() method in onCompletion method:

    @Override
    public void onCompletion() {
        videoWidgetView.seekTo(0);
        videoWidgetView.pauseVideo();
        onDestroy();
    }

Hope it works :)