Change the value of a textarea input on the client

Source: R/update-input.R

Change the value of a textarea input on the client

updateTextAreaInput(
  session = getDefaultReactiveDomain(),
  inputId,
  label = NULL,
  value = NULL,
  placeholder = NULL
)

Arguments

session

The session object passed to function given to shinyServer. Default is getDefaultReactiveDomain().
inputId

The id of the input object.
label

The label to set for the input object.
value

Initial value.
placeholder

A character string giving the user a hint as to what can be entered into the control. Internet Explorer 8 and 9 do not support this option.

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, 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). Similarly, for these inputs, the selected item can be cleared by using selected=character(0).

See also

textAreaInput()

Examples

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

ui <- fluidPage(
  sliderInput("controller", "Controller", 0, 20, 10),
  textAreaInput("inText", "Input textarea"),
  textAreaInput("inText2", "Input textarea 2")
)

server <- function(input, output, session) {
  observe({
    # We'll use the input$controller variable multiple times, so save it as x
    # for convenience.
    x <- input$controller

    # This will change the value of input$inText, based on x
    updateTextAreaInput(session, "inText", value = paste("New text", x))

    # Can also set the label, this time for input$inText2
    updateTextAreaInput(session, "inText2",
      label = paste("New label", x),
      value = paste("New text", x))
  })
}

shinyApp(ui, server)
}