Learn what the heck shiny is and how you use it!

• An interactive report framework
• An R package that is available free (as is the server edition)
• Uses "modern web standards" like bootstrap under the hood

Teaching stats with shiny

Board pack

A shiny application report consists of two functions¹

• shinyServer()
• shinyUI()

One says what to execute and the other states how to present it the results.

defaultdisplay<-list(width="100%", height="75%")

shinyApp(
    ui      = fluidPage()
  , server  = function(input, output) {}
  , options = defaultdisplay
)

You typically split into two files:

• server.R containing shinyServer()
• ui.R containing shinyUI()

This can then be run with runApp()

You can do a single file example app.R which contains both functions but this is typically better for very short apps.

shinyApp(
  ui = fluidPage(dateInput("datePicker"
                , "Pick a date:"
                , format="dd/mm/yy")),
  server = function(input, output) {}
  ,options = defaultdisplay
)

shinyApp(
  ui = fluidPage(sliderInput("vals"
              ,"Insert a number:"
              ,min=0 ,max=50 ,value=15
              ,ticks=FALSE))
  ,server = function(input, output) {}
  ,options = defaultdisplay
)

shinyApp(
  ui = fluidPage(tags$textarea(id="charbox"
                    ,rows=3
                    ,cols=40
                    ,"Default value"))
  ,server = function(input, output) {}
  ,options = defaultdisplay
)

shinyApp(
  ui = fluidPage(selectInput("multiselect"
              ,"Pick favourites:"
              ,c("Green","Red","Blue")
              ,multiple=TRUE))
  ,server = function(input, output) {}
  ,options = defaultdisplay
)

shinyApp(
  ui = fluidPage(textInput("char", "Insert text:") ,
                 textOutput("text")  ),
  server = function(input, output) {
    output$text <- renderText(input$char)
  }  ,options = defaultdisplay
)

quickShiny <- function(uFUN,sFUN,s) {
  require(shiny)
  defaultdisplay <- list(width = "100%", height = "75%")
  shinyApp(
    ui = fluidPage(uFUN("a")),
    server = function(input, output) {
      output$a <- sFUN(s)
    },options = defaultdisplay
  )
}

quickShiny(uFUN = DT::dataTableOutput,
           sFUN = DT::renderDataTable,
           s    = head(iris,5))

quickShiny(uFUN = plotOutput,
           sFUN = renderPlot,
           s    = pairs(iris[,1:3]))

library(leaflet)
quickShiny(uFUN = leafletOutput,
           sFUN = renderLeaflet,
           s    = leaflet() %>%  addTiles() )

library(dygraphs)
quickShiny(uFUN = dygraphOutput,
           sFUN = renderDygraph,
           s    = dygraph(mdeaths))

library(DiagrammeR)
quickShiny(uFUN = grVizOutput,
           sFUN = renderGrViz,
           s    = render_graph(create_random_graph(3,3)))

library(plotly)

## 
## Attaching package: 'plotly'

## The following object is masked from 'package:vegalite':
## 
##     add_data

## The following object is masked from 'package:ggplot2':
## 
##     last_plot

## The following object is masked from 'package:stats':
## 
##     filter

## The following object is masked from 'package:graphics':
## 
##     layout

quickShiny(uFUN = plotlyOutput,
           sFUN = renderPlotly,
           s    = plot_ly(z = volcano, type = "surface"))

uilist<-list(textInput("a","Text","Txt")
      ,textOutput("b"))
shinyApp(ui = fluidPage(uilist)
  ,server = function(input, output) {
    output$b <-renderText(paste0(input$a,"er"))
  },options = defaultdisplay
)

shinyApp(ui = fluidPage(uilist)
  ,server = function(input, output) {
    rand<-reactive({gen<-rpois(1,5)+1
                   paste0(gen,input$a)})
    output$b <-renderText(rand())
  },options = defaultdisplay
)

uilist[[3]]<-actionButton("go","Go")
shinyApp(ui = fluidPage(uilist)
  ,server = function(input, output) {
    rand<-eventReactive(input$go
                  ,{gen<-rpois(1,5)+1
                   paste0(gen,input$a)})
    output$b <-renderText(rand())
  },options = defaultdisplay
)

• Shiny outputs html so you can write CSS that works with it
• Full list of CSS items doesn't exist, use F12 on chrome or check out selectorgadget via rvest
• Standard classes will work

• Get a different look and feel with the package shinythemes
• Uses a number of bootstrap based themes
• Good-looking quickly, but of course not company branded
• View themes at bootswatch.com

• A new dashboarding : Shiny Dashboard
• Still immature but useful
• Excellent walkthrough on Data Driven Security

• Rstudio (easiest) or just run directly
• Use shiny::runApp()
• Great for "expert" use

• shinyApps.io
• Deploy with shinyApps package
• Free for light use
• Extra management features at increased costs
• Great for hands-off management

• shiny-server
• Runs on linux
• Free community edition
• Extra management features & LDAP auth in Pro Edition (but can roll your own)
• Great for sensitive and/or db-driven appplications

• shiny is an easy framework
• shiny is very extendable
• shiny has a variety of deployment options

• Browse on github: stephlocke/Rtraining

• Download everything:

  if (!require(devtools)) install.packages("devtools")
  devtools::install_github("stephlocke/Rtraining")

• Attendees
• Organisers and volunteers

• Shiny site
• A bit outdated but: Web Application Development with R Using Shiny
• Reactivity Overview
• shiny for teaching maths
• Show me Shiny!
• Deploying shiny apps

• Locke Data
• Presenter on Data Science, BI, and DataOps
• Microsoft Data Platform MVP
• User group leader: MSFT Stack & CaRdiff
• Conference organiser: satRdays & Battle of the Beards

github.com/StephLocke | itsalocke.com | T: SteffLocke