gWidgets (version 0.0-54)

gcheckboxgroup: 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,

Usage

gcheckboxgroup(items, checked = FALSE,  horizontal = FALSE, use.table=FALSE,
    handler = NULL, action = NULL, container = NULL, ..., toolkit = guiToolkit())

Arguments

items

Vector of values to select from

checked

A logical vector indicating initial values.

horizontal

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)

# }
# NOT RUN {
# }