[R] tcl/tk return problem

[deggle]

Hello,

I'm very new in working with tcl/tk in R and have a problem which will 
probably
sound silly to most of you.
Here is the code I have problems with:

readcelfiles <- function()
{
   require(tcltk)
   tt <- tktoplevel()
   tkgrid(tklabel(tt,text="Choose a directory!"))

 OnOK <- function()
 {
    fileDir<-tclvalue(tkchooseDirectory())
    data.raw <- ReadAffy(celfile.path=fileDir)
    #return(data.raw)
 }

   OK.but <- tkbutton(tt,text="OK",command=OnOK)
   tkgrid(OK.but)
   tkfocus(tt)
}

So after clicking on my "OK" button, I choose my directory and read the 
cel-files.
But now I want to return the object to my workspace ... "return" doesn't 
work here.

Could anyone give me a hint?

Thank you very much,
Daniela