warnings hidden by gWidgets

Question

I have written a R function which runs the lmer() function from the lme4 package. Sometimes the lmer() function returns some warnings, then I see these warnings when running my function.

However when running my function through an R gWidget the warnings do not appear in the R console. They appear only after I run a new command in the R console. What should I do to see these warnings when running the widget?

I don't know whether my question is clear. My function is very long, a little complex, and takes a file as an argument. I can't copy it here and provide a reproducible example.

Answer 1

For some reasons I think gWidgets redirect the output. One solution is to change the options warn

I create a small code to generate the bug. and I confirm I have the same behaviour.

library(gWidgets)
options("guiToolkit"="RGtk2")

warn.handler <- function(h,...) { warnings('dummy warning')}
win    <- gwindow("Hello World, ad nauseum", visible=TRUE)
 group <- ggroup(horizontal = FALSE, container=win)
 obj   <- gbutton("Hello...",container=group,handler = warn.handler)

here my warn.handler function generate a dummy warning :

warn.handler()
Warning message:
In warn.handler() : dummy warning

but when I run the gwidget , and I click on the button I don't have the warnings.

when I change the options warn

        options(warn=1) # print warnings as they occur

I get the warnings.