% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/update-input.R
\name{updateCheckboxGroupInput}
\alias{updateCheckboxGroupInput}
\title{Change the value of a checkbox group input on the client}
\usage{
updateCheckboxGroupInput(session, inputId, label = NULL,
  choices = NULL, selected = NULL, inline = FALSE,
  choiceNames = NULL, choiceValues = NULL)
}
\arguments{
\item{session}{The \code{session} object passed to function given to
\code{shinyServer}.}

\item{inputId}{The id of the input object.}

\item{label}{The label to set for the input object.}

\item{choices}{List of values to show checkboxes for. If elements of the list
are named then that name rather than the value is displayed to the user. If
this argument is provided, then \code{choiceNames} and \code{choiceValues}
must not be provided, and vice-versa. The values should be strings; other
types (such as logicals and numbers) will be coerced to strings.}

\item{selected}{The values that should be initially selected, if any.}

\item{inline}{If \code{TRUE}, render the choices inline (i.e. horizontally)}

\item{choiceNames}{List of names and values, respectively,
that are displayed to the user in the app and correspond to the each
choice (for this reason, \code{choiceNames} and \code{choiceValues}
must have the same length). If either of these arguments is
provided, then the other \emph{must} be provided and \code{choices}
\emph{must not} be provided. The advantage of using both of these over
a named list for \code{choices} is that \code{choiceNames} allows any
type of UI object to be passed through (tag objects, icons, HTML code,
...), instead of just simple text. See Examples.}

\item{choiceValues}{List of names and values, respectively,
that are displayed to the user in the app and correspond to the each
choice (for this reason, \code{choiceNames} and \code{choiceValues}
must have the same length). If either of these arguments is
provided, then the other \emph{must} be provided and \code{choices}
\emph{must not} be provided. The advantage of using both of these over
a named list for \code{choices} is that \code{choiceNames} allows any
type of UI object to be passed through (tag objects, icons, HTML code,
...), instead of just simple text. See Examples.}
}
\description{
Change the value of a checkbox group input on the client
}
\details{
The input updater functions send a message to the client, telling it to
change the settings of an input object. The messages are collected and sent
after all the observers (including outputs) have finished running.

The syntax of these functions is similar to the functions that created the
inputs in the first place. For example, \code{\link{numericInput}()} and
\code{updateNumericInput()} take a similar set of arguments.

Any arguments with NULL values will be ignored; they will not result in any
changes to the input object on the client.

For \code{\link{radioButtons}()}, \code{\link{checkboxGroupInput}()} and
\code{\link{selectInput}()}, the set of choices can be cleared by using
\code{choices=character(0)}. Similarly, for these inputs, the selected item
can be cleared by using \code{selected=character(0)}.
}
\examples{
## Only run examples in interactive R sessions
if (interactive()) {

ui <- fluidPage(
  p("The first checkbox group controls the second"),
  checkboxGroupInput("inCheckboxGroup", "Input checkbox",
    c("Item A", "Item B", "Item C")),
  checkboxGroupInput("inCheckboxGroup2", "Input checkbox 2",
    c("Item A", "Item B", "Item C"))
)

server <- function(input, output, session) {
  observe({
    x <- input$inCheckboxGroup

    # Can use character(0) to remove all choices
    if (is.null(x))
      x <- character(0)

    # Can also set the label and select items
    updateCheckboxGroupInput(session, "inCheckboxGroup2",
      label = paste("Checkboxgroup label", length(x)),
      choices = x,
      selected = x
    )
  })
}

shinyApp(ui, server)
}
}
\seealso{
\code{\link{checkboxGroupInput}}
}
