How to convert the screen output to PDF of a report?

hi friends,

I am displaying the data in my report using screens.

After displaying the all data on screens, Then when i click a button 'CONVERT TO PDF' ,then the screen output to PDF file and save it to local disk.

I created a button. when i clicked it's showing no spool request generated.

I know converting output list (normal output) to PDF file. But i am unable to convert the screen output to PDF format.

Any helps will be appreciate..............

Regards,

Shankar.