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gWidgets (version 0.0-54.2)

gfile: Dialogs for file and date selection

Description

These functions provide dialogs for file selection (files or directories) and date selections.

Usage

gfile(text = "", type = c("open", "save", "selectdir"), initialfilename = NULL, 
    filter = list("All files" = list(patterns = c("*")), "R files" =
    list(patterns = c("*.R","*.Rdata")),
        "text files" = list(mime.types = c("text/plain"))
        ), multi=FALSE, handler = NULL, action = NULL, ..., toolkit = guiToolkit())

gfilebrowse (text = "Select a file...", type = "open", quote = TRUE, container = NULL, ..., toolkit = guiToolkit())

gcalendar(text = "", format = "%Y-%m-%d", handler=NULL, action=NULL, container = NULL, ..., toolkit = guiToolkit())

Arguments

text

Initial text. For thecalendar, an optional date in a form matching format

type

When selecting a file it can be selected for opening, for saving or you may want to select a directory.

initialfilename

Suggested name for file save

filter

Filter for files shown during selection. Can be nested list, as in example or a named character vector with the names a description and value a file extension (no dots) of files endings to match.

multi

Logical. Allow selection of multiple files?

quote

Is result quoted

format

Format of date, default is year-month-day

handler

Handler for when file is changed. The component file of the first argument contains the file name

action

Passed to handler

container

Optional container to attach widget to

Passed to gedit instance

toolkit

Which GUI toolkit to use

Details

The gfile dialog is modal, meaning no action can take place until a selection is made. Whereas the gfilebrowse dialog consists of a gedit instance to hold a filename and a button to click if the dialog is desired to fill in this filename.

The gcalendar widget is similar to the gfilebrowse widget.

For both gcalendar and gfilebrowse any ... arguments are passed to gedit. The coerce.with argument can be used to here to quote the values, or coerce them otherwise such as with as.Date. Otherwise, the svalue method returns a character string containing the value shown in the gedit box.

The svalue<-() method may be used to set the value for both gcalendar and gfilebrowse .

The return value is the filename selected. A NA value is returned if no file is selected.

Examples

Run this code
# NOT RUN {
## source a file using a handler
sourceFile <- function() gfile("Select a file",type="open", handler =
function(h,...) source(h$file))

## source an R file using fact that dialog is modal
source(gfile(filter=c("R files"="R")))

## apply a generic action to the file
countLines <- function(filename) print(length(readLines(filename)))
chooseFile <- function() gfile("Select a file",type="open",
action="countLines", handler = function(h,...) do.call(h$action,list(h$file)))
# }

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