library(shiny)
library(bslib)

app <- page_sidebar(
  title = "Busy indicators demo",
  sidebar = list(
    selectInput(
      "indicator_types",
      "Busy indicator types",
      c("spinners", "pulse"),
      multiple = TRUE,
      selected = c("spinners", "pulse")
    ),
    downloadButton("download", "Download")
  ),
  # input_dark_mode(),
  card(
    card_header(
      "Plot that takes a few seconds to render",
      actionButton("simulate", "Simulate"),
      class = "d-flex justify-content-between align-items-center"
    ),
    plotOutput("plot")
  ),
  useBusyIndicators(),
  uiOutput("indicator_types_ui")
)


server <- function(input, output, session) {

  output$plot <- renderPlot({
    input$simulate
    Sys.sleep(3)
    plot(1:100, rnorm(100))
  })

  output$indicator_types_ui <- renderUI({
    useBusyIndicators(
      spinners = "spinners" %in% input$indicator_types,
      pulse = "pulse" %in% input$indicator_types
    )
  })

  output$download <- downloadHandler(
    filename = function() {
      paste("data-", Sys.Date(), ".csv", sep="")
    },
    content = function(file) {
      Sys.sleep(4)
      write.csv(mtcars, file)
    }
  )

}

shinyApp(app, server)

library(shiny)
library(bslib)

card_ui <- function(id, spinner_type = id) {
  card(
    busyIndicatorOptions(
      spinner_type = spinner_type,
      spinner_selector = NA
    ),
    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)