something.js

appView.getView().setId(100);
appView.getView().setLayoutParams(new FrameLayout.LayoutParams(
        ViewGroup.LayoutParams.MATCH_PARENT,
        ViewGroup.LayoutParams.MATCH_PARENT));

setContentView(appView.getView());

if (preferences.contains("BackgroundColor")) {
    int backgroundColor = preferences.getInteger("BackgroundColor", Color.BLACK);
    // Background of activity:
    appView.getView().setBackgroundColor(backgroundColor);
}

appView.getView().requestFocusFromTouch();