Shiny automatically includes busy indicators, which more specifically means:

  1. Calculating/recalculating outputs have a spinner overlay.

  2. Outputs fade out/in when recalculating.

  3. When no outputs are calculating/recalculating, but Shiny is busy doing something else (e.g., a download, side-effect, etc), a page-level pulsing banner is shown.

This function allows you to customize the appearance of these busy indicators by including the result of this function inside the app's UI. Note that, unless spinner_selector (or fade_selector) is specified, the spinner/fade customization applies to the parent element. If the customization should instead apply to the entire page, set spinner_selector = 'html' and fade_selector = 'html'.

busyIndicatorOptions(
  ...,
  spinner_type = NULL,
  spinner_color = NULL,
  spinner_size = NULL,
  spinner_delay = NULL,
  spinner_selector = NULL,
  fade_opacity = NULL,
  fade_selector = NULL,
  pulse_background = NULL,
  pulse_height = NULL,
  pulse_speed = NULL
)

Arguments

...

Currently ignored.

spinner_type

The type of spinner. Pre-bundled types include: 'ring', 'ring2', 'ring3', 'bars', 'bars2', 'bars3', 'pulse', 'pulse2', 'pulse3', 'dots', 'dots2', 'dots3'.

A path to a local SVG file can also be provided. The SVG should adhere to the following rules:

  • The SVG itself should contain the animation.

  • It should avoid absolute sizes (the spinner's containing DOM element size is set in CSS by spinner_size, so it should fill that container).

  • It should avoid setting absolute colors (the spinner's containing DOM element color is set in CSS by spinner_color, so it should inherit that color).

spinner_color

The color of the spinner. This can be any valid CSS color. Defaults to the app's "primary" color if Bootstrap is on the page.

spinner_size

The size of the spinner. This can be any valid CSS size.

spinner_delay

The amount of time to wait before showing the spinner. This can be any valid CSS time and can be useful for not showing the spinner if the computation finishes quickly.

spinner_selector

A character string containing a CSS selector for scoping the spinner customization. The default (NULL) will apply the spinner customization to the parent element of the spinner.

fade_opacity

The opacity (a number between 0 and 1) for recalculating output. Set to 1 to "disable" the fade.

fade_selector

A character string containing a CSS selector for scoping the spinner customization. The default (NULL) will apply the spinner customization to the parent element of the spinner.

pulse_background

A CSS background definition for the pulse. The default uses a linear-gradient of the theme's indigo, purple, and pink colors.

pulse_height

The height of the pulsing banner. This can be any valid CSS size.

pulse_speed

The speed of the pulsing banner. This can be any valid CSS time.

See also

useBusyIndicators() to disable/enable busy indicators.

Examples

if (FALSE) { # rlang::is_interactive()

library(bslib)

card_ui <- function(id, spinner_type = id) {
  card(
    busyIndicatorOptions(spinner_type = spinner_type),
    card_header(paste("Spinner:", spinner_type)),
    plotOutput(shiny::NS(id, "plot"))
  )
}

card_server <- function(id, simulate = reactive()) {
  moduleServer(
    id = id,
    function(input, output, session) {
      output$plot <- renderPlot({
        Sys.sleep(1)
        simulate()
        plot(x = rnorm(100), y = rnorm(100))
      })
    }
  )
}

ui <- page_fillable(
  useBusyIndicators(),
  input_task_button("simulate", "Simulate", icon = icon("refresh")),
  layout_columns(
    card_ui("ring"),
    card_ui("bars"),
    card_ui("dots"),
    card_ui("pulse"),
    col_widths = 6
  )
)

server <- function(input, output, session) {
  simulate <- reactive(input$simulate)
  card_server("ring", simulate)
  card_server("bars", simulate)
  card_server("dots", simulate)
  card_server("pulse", simulate)
}

shinyApp(ui, server)
}