I want to add menu bar, tool bar stuff.
So which problem exactly are you trying to solve? Are you looking for QtQuick widgets displaying menu and bars (it doesn't look related to OCCT Viewer)?
I have reviewed the AndroidQt application. However, I think the viewer class is out of date.
What do you mean by "out of date"? It doesn't use AIS_ViewController and doesn't do much stuff, but should be still workable. Haven't built this particular sample for many years, though.