Can Saveas prompt for location, but still use a system generated filename

I have a client that's wanting to save a pdf file of a datawindow.

But, they want the program to prompt them for the location to save the file.

It looks like you can do a saveas and leave the filename blank.

and, it will prompt the user for the path/filename

is there a way, that I can prompt them.... but, put the filename that was generated by

the program, on the filename line

I thought I had done something like this, for import of a file

but, I don't think I've done a saveas

does this make sense?

basically.... I want the user to be able to chose the path

but, not necessarily the filename... maybe just put, the generated one

can this be done on the screen, that's prompted for... in the saveas routine?

i guess I could have them specify both... if I had to