Build a "Hello, world" Shiny app

Building Web Applications with Shiny in R

Kaelen Medeiros

Data Scientist

Parts of a Shiny app

library(shiny)

ui <- fluidPage()

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

}

shinyApp(ui = ui, server = server)

Load shiny
Create the UI with a HTML function
Define a custom function to create the server
Run the app

Hello, world!!!

library(shiny)

ui <- fluidPage(
    "Hello, world!!!"
)

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

}

shinyApp(ui = ui, server = server)

A blank web page that displays character string "Hello, world!!!"

Ask a question (with an input!)

ui <- fluidPage(
    textInput("name", "Enter a name:"),

    textOutput("q")

)

server <- function(input, output) {

    output$q <- renderText({
        paste("Do you prefer dogs 
                    or cats,", 
              input$name, "?")
      })

}

A web app that allows users to enter a name and then asks "Do you prefer dogs or cats, name?"

Let's practice!

Building Web Applications with Shiny in R