R help - Nov 2008 - tklistbox - R-Objekt

Hello, I have a problem with a tklistbox. The user should be able to choose
one out of two calculation methods needed for further calculations. My
r-script for that purpose looks like that:

    require(tcltk)
    tt<-tktoplevel()
   
tl<-tklistbox(tt,height=4,selectmode="single",background="white")
    tkgrid(tklabel(tt,text="select method for LAI calculation"))
    tkgrid(tl)
    method<- c("method1","method2")
    for (i in (1:2)){
        tkinsert(tl,"end",method[i])
        }
    tkselection.set(tl,0)
    OnOK <- function(){
    	choice<-method[as.numeric(tkcurselection(tl))+1]
           tkdestroy(tt)
            }
    OK.but <-tkbutton(tt,text="   OK   ",command=OnOK)
    tkbind(tkgrid, "<Return>",OnOK)
    tkgrid(OK.but)

The function works, but it does not create any r-object to that I can access
later on. How do I have to modify the function that I get an object with the
value "method1" or "method2"?

-----
Tamara Hoebinger
University of Vienna
-- 
View this message in context:
http://www.nabble.com/tklistbox---R-Objekt-tp20649714p20649714.html
Sent from the R help mailing list archive at Nabble.com.

This is safest if the below code is wrapped in another function.

At the top level function (or whatever level you will be using your choice
information at) first create the variable named choice with a default value
(choice <- "").

In your OnOk function, change "choice<-" to
"choice<<-", this will make the function change the value of the
previously created variable, rather than create a local variable (which goes
away before you do anything with it).

Hope this helps,

--
Gregory (Greg) L. Snow Ph.D.
Statistical Data Center
Intermountain Healthcare
greg.snow at imail.org
801.408.8111

> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of thoeb
> Sent: Sunday, November 23, 2008 12:18 PM
> To: r-help at r-project.org
> Subject: [R] tklistbox - R-Objekt
>
>
> Hello, I have a problem with a tklistbox. The user should be able to
> choose
> one out of two calculation methods needed for further calculations. My
> r-script for that purpose looks like that:
>
>     require(tcltk)
>     tt<-tktoplevel()
>    
tl<-tklistbox(tt,height=4,selectmode="single",background="white")
>     tkgrid(tklabel(tt,text="select method for LAI calculation"))
>     tkgrid(tl)
>     method<- c("method1","method2")
>     for (i in (1:2)){
>         tkinsert(tl,"end",method[i])
>         }
>     tkselection.set(tl,0)
>     OnOK <- function(){
>         choice<-method[as.numeric(tkcurselection(tl))+1]
>            tkdestroy(tt)
>             }
>     OK.but <-tkbutton(tt,text="   OK   ",command=OnOK)
>     tkbind(tkgrid, "<Return>",OnOK)
>     tkgrid(OK.but)
>
> The function works, but it does not create any r-object to that I can
> access
> later on. How do I have to modify the function that I get an object
> with the
> value "method1" or "method2"?
>
> -----
> Tamara Hoebinger
> University of Vienna
> --
> View this message in context: http://www.nabble.com/tklistbox---R-
> Objekt-tp20649714p20649714.html
> Sent from the R help mailing list archive at Nabble.com.
>
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