updateSelectInput: Change the value of a select input on the client
In ymd526442121/Rproject_shiny: Web Application Framework for R

Description Usage Arguments Details See Also Examples

Change the value of a select input on the client

updateSelectInput(session, inputId, label = NULL, choices = NULL,
  selected = NULL)

updateSelectizeInput(session, inputId, label = NULL, choices = NULL,
  selected = NULL, options = list(), server = FALSE)

`session`	The `session` object passed to function given to `shinyServer`.
`inputId`	The id of the input object.
`label`	The label to set for the input object.
`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.
`selected`	The initially selected value (or multiple values if `multiple = TRUE`). If not specified then defaults to the first value for single-select lists and no values for multiple select lists.
`options`	A list of options. See the documentation of selectize.js for possible options (character option values inside `I()` will be treated as literal JavaScript code; see `renderDataTable()` for details).
`server`	whether to store `choices` on the server side, and load the select options dynamically on searching, instead of writing all `choices` into the page at once (i.e., only use the client-side version of selectize.js)

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, numericInput() and 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 radioButtons(), checkboxGroupInput() and selectInput(), the set of choices can be cleared by using choices=character(0).

selectInput

## Only run examples in interactive R sessions
if (interactive()) {

ui <- fluidPage(
  p("The checkbox group controls the select input"),
  checkboxGroupInput("inCheckboxGroup", "Input checkbox",
    c("Item A", "Item B", "Item C")),
  selectInput("inSelect", "Select input",
    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
    updateSelectInput(session, "inSelect",
      label = paste("Select input label", length(x)),
      choices = x,
      selected = tail(x, 1)
    )
  })
}

shinyApp(ui, server)
}