the hidden Navigationbar is appeared when toolbar menu button is clicked

Question

I have used the method presented here to hide Navigationbar. It works properly but when I tap the context menu button (three vertical points in the right side of the toolbar), the navigationbar is appeared again.

I have used the code:

    View decorView = getWindow().getDecorView();
    decorView.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE
            | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
            | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
            | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
            | View.SYSTEM_UI_FLAG_FULLSCREEN
            | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY);

in onResume(), onCreate(), onOptionsItemSelected(), onWindowFocusChanged().

If all of menu items are set to app:showAsAction="always" the Navigationbar is never appeared but when some are shown in the list, it appeard.