[R-gui] Preventing gdf from adding rows and columns to a data frame

[jverzani]

Hana Sevcikova <hanas <at> uw.edu> writes:

> 
> Hello everyone,
> 
> Is it possible to restrict gdf (from gwidgets) in a way that it adds 
> neither rows nor columns (and possibly doesn't allow to change row and 
> column names)?
> I'd like a widget where the user can only edit the values of a data 
> frame, not change its dimensions. I really like gdf but the feature of 
> adding rows and columns would be quite confusing in my specific application.
> 
> Thanks a lot,
> 
> Hana
> 

Dear Hana,

Not really. However, you can get a start on what you want by modifying the
following. It uses a nifty one liner by Michael Lawrence to add the cell
renders. The model variable has the usual data frame methods to access the data.

Hope this helps. --J


library(RGtk2) ## need this
library(gWidgets)
options(guiToolkit="RGtk2")



model <- rGtkDataFrame(mtcars)
view <- gtkTreeView(model)
## Michael Lawrence's trick to add cell renderer's
mapply(view$insertColumnWithAttributes,  -1, colnames(model), 
       list(gtkCellRendererText()), text = seq_len(ncol(model)) - 1)

sw <- gtkScrolledWindow()
sw$add(view)

sapply(1:ncol(model), function(j) {
  cr <- view$getColumn(j-1)$getCellRenderers()[[1]]
  cr['editable'] <- TRUE
  gSignalConnect(cr, "edited", 
                 f=function(cr, path, newtext, user.data) {
                   curRow <- as.numeric(path) + 1
                   curCol <- user.data$column
                   model <- user.data$model
                   ## coerce newtext from character to desired type
                   ## otherwise this coerces to character
                   model[curRow, curCol] <- as.numeric(newtext)
                 }, data=list(model=model, column=j))
})

## How to add within a gWidgets GUI
w <- gwindow("test")
g <- ggroup(cont=w)
add(g, sw, expand=TRUE)