How to add event to button after create tween to it?

I have set of buttons, normally I would let button stay as it is and call its instance name to add event listener. But this time I tried to make it moving, I created a classic tween to it, then named the classic tween instance name. 

Normally, this is the code:

this.btn_name.on("click", function() {...});

So this time, I just add the tween's instance name before it:

this.tween_name.btn_name.on("click", function() {...});

And it's not working anymore. I can't seem to find the answer in the community. Please help.