Code Editor for app.R

library(shiny)

ui <- htmlTemplate("template.html",
                  message = "Hello from Shiny!",
                  controls = tagList(
                    textInput("name", "What's your name?"),
                    actionButton("greet", "Greet")
                  ),
                  result = uiOutput("greeting")
)

server <- function(input, output, session) {
  output$greeting <- renderUI({
    req(input$greet)
    HTML(paste0("<p class='greeting'>Hello, ", input$name, "!</p>"))
  })
}

shinyApp(ui = ui, server = server)