shiny/man/selectInput.Rd

% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/input-select.R
\name{selectInput}
\alias{selectInput}
\alias{selectizeInput}
\title{Create a select list input control}
\usage{
selectInput(inputId, label, choices = NULL, selected = NULL,
  multiple = FALSE, selectize = TRUE, width = NULL, size = NULL,
  choiceNames = NULL, choiceValues = NULL)

selectizeInput(inputId, ..., options = NULL, width = NULL)
}
\arguments{
\item{inputId}{The \code{input} slot that will be used to access the value.}

\item{label}{Display label for the control, or \code{NULL} for no label.}

\item{choices}{List of values to select from. If elements of the list are
named, then that name rather than the value is displayed to the user.
This can also be a named list whose elements are (either named or
unnamed) lists or vectors. If this is the case, the outermost names
will be used as the "optgroup" label for the elements in the respective
sublist. This allows you to group and label similar choices. See the
example section for a small demo of this feature.}

\item{selected}{The initially selected value (or multiple values if
\code{multiple = TRUE}). If not specified then defaults to the first value
for single-select lists and no values for multiple select lists.}

\item{multiple}{Is selection of multiple items allowed?}

\item{selectize}{Whether to use \pkg{selectize.js} or not.}

\item{width}{The width of the input, e.g. \code{'400px'}, or \code{'100\%'};
see \code{\link{validateCssUnit}}.}

\item{size}{Number of items to show in the selection box; a larger number
will result in a taller box. Not compatible with \code{selectize=TRUE}.
Normally, when \code{multiple=FALSE}, a select input will be a drop-down
list, but when \code{size} is set, it will be a box instead.}

\item{choiceNames, 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. For \code{selectInput} and \code{selectizeInput},
there isn't any particular advantage to using both of these over
a named list for \code{choices} and it is simply a matter of preference
(this is not always the case; for example, \code{\link{radioButtons}} and
\code{\link{checkboxGroupInput}} can use \code{choiceNames} to pass HTML
code, instead of simple text).}

\item{...}{Arguments passed to \code{selectInput()}.}

\item{options}{A list of options. See the documentation of \pkg{selectize.js}
for possible options (character option values inside \code{\link[base]{I}()} will
be treated as literal JavaScript code; see \code{\link{renderDataTable}()}
for details).}
}
\value{
A select list control that can be added to a UI definition.
}
\description{
Create a select list that can be used to choose a single or multiple items
from a list of values.
}
\details{
By default, \code{selectInput()} and \code{selectizeInput()} use the
JavaScript library \pkg{selectize.js}
(\url{https://github.com/selectize/selectize.js}) to instead of the basic
select input element. To use the standard HTML select input element, use
\code{selectInput()} with \code{selectize=FALSE}.

In selectize mode, if the first element in \code{choices} has a value of
\code{""}, its name will be treated as a placeholder prompt. For example:
\code{selectInput("letter", "Letter", c("Choose one" = "", LETTERS))}
}
\note{
The selectize input created from \code{selectizeInput()} allows
  deletion of the selected option even in a single select input, which will
  return an empty string as its value. This is the default behavior of
  \pkg{selectize.js}. However, the selectize input created from
  \code{selectInput(..., selectize = TRUE)} will ignore the empty string
  value when it is a single choice input and the empty string is not in the
  \code{choices} argument. This is to keep compatibility with
  \code{selectInput(..., selectize = FALSE)}.
}
\examples{
## Only run examples in interactive R sessions
if (interactive()) {

# basic example
shinyApp(
  ui = fluidPage(
    selectInput("variable", "Variable:",
                c("Cylinders" = "cyl",
                  "Transmission" = "am",
                  "Gears" = "gear")),
    tableOutput("data")
  ),
  server = function(input, output) {
    output$data <- renderTable({
      mtcars[, c("mpg", input$variable), drop = FALSE]
    }, rownames = TRUE)
  }
)

# demoing optgroup support in the `choices` arg
shinyApp(
  ui = fluidPage(
    selectInput("state", "Choose a state:",
      list(`East Coast` = c("NY", "NJ", "CT"),
           `West Coast` = c("WA", "OR", "CA"),
           `Midwest` = c("MN", "WI", "IA"))
    ),
    textOutput("result")
  ),
  server = function(input, output) {
    output$result <- renderText({
      paste("You chose", input$state)
    })
  }
)
}
}
\seealso{
\code{\link{updateSelectInput}}

Other input elements: \code{\link{actionButton}},
  \code{\link{checkboxGroupInput}},
  \code{\link{checkboxInput}}, \code{\link{dateInput}},
  \code{\link{dateRangeInput}}, \code{\link{fileInput}},
  \code{\link{numericInput}}, \code{\link{passwordInput}},
  \code{\link{radioButtons}}, \code{\link{sliderInput}},
  \code{\link{submitButton}}, \code{\link{textAreaInput}},
  \code{\link{textInput}}
}