input_submit_textarea: Create a textarea input control with explicit submission

In bslib: Custom 'Bootstrap' 'Sass' Themes for 'shiny' and 'rmarkdown'

Create a textarea input control with explicit submission

Description

Creates a textarea input where users can enter multi-line text and submit their input using a dedicated button or keyboard shortcut. This control is ideal when you want to capture finalized input, rather than reacting to every keystroke, making it useful for chat boxes, comments, or other scenarios where users may compose and review their text before submitting.

Usage

input_submit_textarea(
  id,
  label = NULL,
  ...,
  placeholder = NULL,
  value = "",
  width = "min(680px, 100%)",
  rows = 1,
  button = NULL,
  toolbar = NULL,
  submit_key = c("enter+modifier", "enter")
)

update_submit_textarea(
  id,
  ...,
  value = NULL,
  placeholder = NULL,
  label = NULL,
  submit = FALSE,
  focus = FALSE,
  session = get_current_session()
)

Arguments

id	The input ID.
label	The label to display above the input control. If NULL, no label is displayed.
...	Additional attributes to apply to the underlying ⁠<textarea>⁠ element (e.g., spellcheck, autocomplete, etc).
placeholder	The placeholder text for the user input.
value	The value to set the user input to.
width	Any valid CSS unit (e.g., width="100%").
rows	The number of rows (i.e., height) of the textarea. This essentially sets the minimum height – the textarea can grow taller as the user enters more text.
button	A htmltools::tags element to use for the submit button. It's recommended that this be a input_task_button() since it will automatically provide a busy indicator (and disable) until the next flush occurs. Note also that if the submit button launches a shiny::ExtendedTask, this button can also be bound to the task (bind_task_button()) and/or manually updated for more accurate progress reporting (update_task_button()).
toolbar	A list of optional UI elements (e.g., links, icons) to display next to the submit button.
submit_key	A character string indicating what keyboard event should trigger the submit button. The default is enter+modifier, which requires the user to hold down Ctrl (or Cmd on Mac) before pressing Enter to submit. This helps prevent accidental submissions. To allow submission with just the Enter key, use enter. In this case, the user can still insert new lines using Shift+Enter or Alt+Enter.
submit	Whether to automatically submit the text for the user. Requires value.
focus	Whether to move focus to the input element. Requires value.
session	The session object; using the default is recommended.

Value

A textarea input control that can be added to a UI definition.

Server value

The server receives a character string containing the user's text input.

Important: The initial server value is always "" (empty string), regardless of any value parameter provided to input_submit_textarea(). The server value updates only when the user explicitly submits the input by either pressing the Enter key (possibly with a modifier key) or clicking the submit button.

See Also

update_submit_textarea(), input_task_button()

Examples

library(shiny)
library(bslib)

ui <- page_fluid(
  input_submit_textarea("text", placeholder = "Enter some input..."),
  verbatimTextOutput("value")
)
server <- function(input, output) {
  output$value <- renderText({
    req(input$text)
    Sys.sleep(2)
    paste("You entered:", input$text)
  })
}
shinyApp(ui, server)

bslib documentation built on May 16, 2026, 9:06 a.m.