R: Widget to allow multiple selection from a vector of items
gcheckboxgroup
R Documentation
Widget to allow multiple selection from a vector of items
Description
Widgets to select one (or several) from a given vector of
items. These are a radio group where all values are shown at once,
but only one may be selected; a checkbox group where more than one
may be selected; and a
combo box (or droplist) where initially only a single value is shown, and the others
are a mouse click away,
A logical specifying the layout for gradio and gcheckboxgroup
handler
Called when selection is changed
use.table
If TRUE a table with checkboxes will be used
instead (toolkit depending) so that one can scroll through the values
action
Passed to handler when called.
container
Optional container to attach widget to
...
Passed to add method of container
toolkit
Which GUI toolkit to use
Details
The svalue method returns the selected values by
name. If the extra argument index=TRUE is specified,
the indices of the selected values is given.
The svalue<- method can be used to set the selected
value. This widget is a cross between a checkbox and a radio
button group. As such, there are different ways to specify the
state. As with a checkbox, the argument can be a logical
vector indicating which checkboxes are to be checked
(recycling is done). As with a radio button group, the value
can be a character vector indicating by label which checkboxes
are to be checked; or if the index=TRUE argument is
given, a vector of indices for those checkboxes to be checked.
The "[" method refers to the vector defining the items.
The "[<-" method can be used to change the vector
defining the items. The length should be the same as the
original, although in some toolkits this isn't necessary.
The "length" method returns the number of items.
See Also
A checkboxgroup is one of several ways to select a value of a
set of items. See also
gcheckbox,
gradio,
gcombobox, and
gtable.
Methods for gComponent objects are detailed in gWidgets-methods.
Event Handlers are detailed in gWidgets-handlers.
Examples
## Not run:
flavors <- c("vanilla", "chocolate", "strawberry")
f <- function(h,...) print(
paste("Yum",
paste(svalue(h$obj),collapse=" and "),
sep = " "))
w <- gwindow("checkbox example")
gp <- ggroup(container=w)
glabel("Favorite flavors:",container=gp)
cbg <- gcheckboxgroup(flavors, container=gp, handler=f)
svalue(cbg) <- c(TRUE, FALSE, TRUE)
svalue(cbg)
svalue(cbg) <- "vanilla"
svalue(cbg, index=TRUE) <- 1:2
cbg[3] <- "raspberry"
## use a table to display (toolkit specific) so that scrollars can be used
cbg <- gcheckboxgroup(letters, container=gwindow(), use.table=TRUE)
## End(Not run)