Build an HMI based on PhAb without mouse.

I need some advice on an adaptation to make on a Photon Application.

I’ve already build an Navigation HMI on Photon : it works on x86 with use of Keyboard and Mouse.

This application uses several PtMenuBar, PtPane, PtRaw, PtList, PtCombo Photon widgets, with classical callbacks linked to them.

I have to build same features on Car Radio embedded (in car …). This radio has got several buttons (OK, Cancel, Directionnal N/S/W/E, 6 Hard Menu buttons).

After a first analysis, my conclusions are the following:
As pinpoint is not managed in Radio (no mouse, or similar, available), my HMI has to give focus to widget, depending on actions on Buttons.
All actions on buttons must be interpreted by this “Active widget”.

My questions are:
my HMI manages the “Active widget”, which is the one who has got the focus : That’s right ?
As every widget defined in my application could be become “Active widget” during execution, what is the best way to avoid to define a callback for each widget and for each possible Buttons ?
I think to use :
PtSendEventToWidget to send event to the “Active widget”, .
Hotkey callback to intercept the event, on the “Active widget”, .
That’s right ?

Thx for help !