Tab order/index for nodes

Is there currently a way to manage the tab index of nodes. Given that cocos2d-x is on the desktop it might be important to be able to tab to various ui components etc or even for platforms that support joypads. I would like to add this feature myself but I thought I would get a discussion going to see if anyone else is interested and get some ideas.

Eg. do we add tab order/tab index to all nodes? or should it just be restricted to menu item controls, buttons and lists via an interface like CCTabableProtocol?

Anyway, really interested to hear ideas and thoughts.

Thanks