The waiter lets you programmatically show and hide partial or full page loading screens with spinners or loading bars to keep your users patiently waiting as you load or compute fancy things.

Examples

Below are simple examples of applications that use the package, consult the website for more.

Waiter

To use the waiter:

1. Include use_waiter in your UI.
2. Trigger show_waiter to show the waiting screen.
3. Eventually trigger hide_waiter to hide the loading screen.

library(shiny)
library(waiter)

ui <- fluidPage(
  use_waiter(), # include dependencies
  waiter_show_on_load(),
  actionButton("show", "Show loading for 3 seconds")
)

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

  observeEvent(input$show, {

    waiter_show( # show the waiter
      spin_fading_circles() # use a spinner
    )

    Sys.sleep(3) # do something that takes time
    
    waiter_hide() # hide the waiter
  })
  
}

shinyApp(ui, server)

The waiter includes more options to customise the spinner, the background, show the waiter on load, etc.

Waitress

To use the waitress:

1. Include use_waitress in your UI.
2. Initialise a waitress from the Waitress object with the new method.
3. You must then call the start.
4. On the waitress object use the increase method to increase the progress bar.
5. Use the hide method when done.

library(shiny)
library(waiter)

ui <- fluidPage(
  use_waitress(),
  p("App content")
)

server <- function(input, output){

  # call the waitress
  waitress <- Waitress$
    new(theme = "overlay-percent")$
    start() # start

  for(i in 1:10){
    waitress$inc(10) # increase by 10%
    Sys.sleep(.3)
  }

  # hide when it's done
  waitress$close() 

}

shinyApp(ui, server)

There are more options to the waitress, you can have it overlay any element (such as the navbar), automagically increment it, etc.

Get it

You can install waiter from CRAN.

install.packages("waiter")

Or the development version from Github with:

install.packages("remotes")
remotes::install_github("JohnCoene/waiter")

Please note that the ‘waiter’ project is released with a Contributor Code of Conduct. By contributing to this project, you agree to abide by its terms.