Toast notifications

Toast notifications are lightweight, temporary messages designed to mimic push notifications from mobile and desktop operating systems. They are built on Bootstrap 5's toast component.

bslib includes a complete example of toasts and their many configuration options:

shiny::runExample("toast", package = "bslib")

Usage

toast(
  ...,
  header = NULL,
  icon = NULL,
  id = NULL,
  type = NULL,
  duration_s = 5,
  position = "top-right",
  closable = TRUE
)

toast_header(title, ..., icon = NULL, status = NULL)

Arguments

...

Body content of the toast. Can be a string, or any HTML elements. Named arguments will be treated as HTML attributes for the toast container.

header

Optional header content. Can be a string, or the result of toast_header(). If provided, creates a .toast-header with close button (if closable = TRUE).

icon

Optional icon element, for example from shiny::icon(), bsicons::bs_icon() or fontawesome::fa().

id

Optional unique identifier for the toast. If NULL, an ID will be automatically generated when the toast is shown via show_toast(). Providing a stable ID allows you to hide the toast later. If a toast with id is already visible, that toast is automatically hidden before showing the new toast with the same id so that only one toast with a given ID is shown at once.

type

Optional semantic type. One of NULL, "primary", "secondary", "success", "info", "warning", "danger", "light", or "dark". Applies appropriate Bootstrap background utility classes (text-bg-*).

duration_s

Numeric. Number of seconds after which the toast should automatically hide. Use 0, or NA to disable auto-hiding (toast will remain visible until manually dismissed). Default is 5 (5 seconds).

position

String or character vector specifying where to position the toast container. Can be provided in several formats:

• Kebab-case: "top-left", "bottom-right", etc.

• Space-separated: "top left", "bottom right", etc.

• Character vector: c("top", "left"), c("bottom", "right"), etc.

• Any order: "left top" is equivalent to "top left"

Valid vertical positions are "top", "middle", or "bottom". Valid horizontal positions are "left", "center", or "right". Input is case-insensitive. Default is "bottom-right".

closable

Logical. Whether to include a close button. Defaults to TRUE. When both duration_s = NA (or 0 or NULL) and closable = FALSE, the toast will remain visible until manually hidden via hide_toast(). This is useful when the toast contains interactive Shiny UI elements and you want to manage the toast display programmatically.

title

Header text (required).

status

Optional status text that appears as small, muted text on the right side of the header.

Value

A bslib_toast object that can be passed to show_toast().

For toast_header(): a toast header object that can be used with the header argument of toast().

Functions

• toast(): Create a toast element.

• toast_header(): Create a structured toast header with optional icon and status indicator. Returns a data structure that can be passed to the header argument of toast().

See also

show_toast() to display a toast, hide_toast() to dismiss a toast, and toast_header() to create structured headers.

Other Toast components: show_toast()

Examples

if (FALSE) { # rlang::is_interactive()
library(shiny)
library(bslib)

ui <- page_fluid(
  actionButton("show_simple", "Simple Toast"),
  actionButton("show_header", "Toast with Header")
)

server <- function(input, output, session) {
  observeEvent(input$show_simple, {
    show_toast(
      toast(
        "Operation completed successfully!",
        header = "Success",
        type = "success"
      )
    )
  })

  observeEvent(input$show_header, {
    show_toast(
      toast(
        "Your settings have been saved.",
        header = toast_header(
          title = "Settings Updated",
          status = "just now"
        ),
        type = "success"
      )
    )
  })
}

shinyApp(ui, server)
}