beginner question: common slot function for multiple buttons

[Zidarics Zoltan]

Hello All,

I am new in KDE. I would like to make a number keyboard for a touch screen
application. 
I need to assign one slot to handle all of button click (0-9):

void Cleaner::btnNumberClick() {
        passWd.append("");
}

How can I know what is the sender button, to append value of button to
passwd string?


thanks
Zamek