How to display the selection screen file name dynamically

Hi All,

I have 2 radio buttons and one output file path in selection screen .

IF I initialised the default file path in initialisation event , It will gives only one radiobutton.

But my requitremenr was If I selected 1st button one file name will be displayed , IF I selected

2nd button I need another file name. How can we change dinamacally.

Please suggest me.