Select options

Hi Friends,

In reports i defined a selection screen.in that based on particular radiobutton i need to display particular fields. all the other fields is not displayed on screen.i did taht by using loop at screen.but here my problem is

if i select r1 then i need to display parameter1 as input field.

when i select r2 i need to display parameter2 as input field. here the parameter1 box is not displaying but also i want to delete the text symbol of the parameter1.

can any one send ur valuable suggestions.

Thanks,

Srinivas.