Loading Page for Shiny Dashboard

Question

I am trying to create a loading page for my dashboard but I can't seem to get it to work. I followed the example here; Shiny Dashboard - display a dedicated "loading.." page until initial loading of the data is done but it is for fluid page and not shiny dashboard and I can't figure out how to adapt it.

Any help would be appreciated!

I would preferably like the loading page just to be a fluid page (no header or sidebar) and then have my main dashboard have the shiny dashboard aspects.

Extra: If I could add a gif to the loading screen, that would be amazing. Something like:

<iframe src="https://giphy.com/embed/BlmF3MhGfa4SY" width="480" height="360" frameBorder="0" class="giphy-embed" allowFullScreen></iframe><p><a href="https://giphy.com/gifs/plane-BlmF3MhGfa4SY">via GIPHY</a></p>

[break]

library (shiny)
library (shinydashboard)
library(shinyjs)


rm(list=ls())

appCSS <- "
#loading_page {
  position: absolute;
  background: #000000;
  opacity: 0.9;
  z-index: 100;
  left: 0;
  right: 0;
  height: 100%;
  text-align: center;
  color: #FFFFFF;
}
"
header <- dashboardHeader()
sidebar <- dashboardSidebar()
body <- dashboardBody("It worked!")


ui <- dashboardPage(
  useShinyjs(),
  inlineCSS(appCSS),
  div(
    id = "loading_page",
    dashboardHeader(),
    dashboardSidebar(),
    dashboardBody("Loading...")
  ),
  hidden(
    div(
      id = "main_content",
      header, sidebar, body
    )
  )
)


server = function(input, output, session) {
    # Simulate work being done for 4 second
    Sys.sleep(4)

    hide("loading_page")
    show("main_content") 
  }

shinyApp(ui, server)

Answer 1

Try this library shinycssloaders

library(shiny)
library(shinycssloaders)
library(highcharter)

ui <- fluidPage(
        mainPanel(
                plotOutput("my_plot")  %>% withSpinner(color="#0dc5c1")
        )
)

server <- function(input, output){
        
        output$my_plot <- renderPlot({
                Sys.sleep(1)
                plot(mtcars)})
}

shinyApp(ui, server)