Outputting multiple lines of text with renderText() in R shiny

72
votes

I want to output multiple lines of text using one renderText() command. However, this does not seem possible. For example, from the shiny tutorial we have truncated code in server.R:

shinyServer(
  function(input, output) {
    output$text1 <- renderText({paste("You have selected", input$var)
    output$text2 <- renderText({paste("You have chosen a range that goes from",
      input$range[1], "to", input$range[2])})
  }
)

and code in ui.R:

shinyUI(pageWithSidebar(

  mainPanel(textOutput("text1"),
            textOutput("text2"))
))

which essentially prints two lines:

You have selected example
You have chosen a range that goes from example range.

Is it possible to combine the two lines output$text1 and output$text2 into one block of code? My efforts so far have failed, e.g.

output$text = renderText({paste("You have selected ", input$var, "\n", "You have chosen a range that goes from", input$range[1], "to", input$range[2])})

Anyone have any ideas?

3
rshiny

3 Answers

107
votes

You can use renderUI and htmlOutput instead of renderText and textOutput.

require(shiny)
runApp(list(ui = pageWithSidebar(
  headerPanel("censusVis"),
  sidebarPanel(
    helpText("Create demographic maps with 
      information from the 2010 US Census."),
    selectInput("var", 
                label = "Choose a variable to display",
                choices = c("Percent White", "Percent Black",
                            "Percent Hispanic", "Percent Asian"),
                selected = "Percent White"),
    sliderInput("range", 
                label = "Range of interest:",
                min = 0, max = 100, value = c(0, 100))
  ),
  mainPanel(textOutput("text1"),
            textOutput("text2"),
            htmlOutput("text")
  )
),
server = function(input, output) {
  output$text1 <- renderText({paste("You have selected", input$var)})
  output$text2 <- renderText({paste("You have chosen a range that goes from",
                                    input$range[1], "to", input$range[2])})
  output$text <- renderUI({
    str1 <- paste("You have selected", input$var)
    str2 <- paste("You have chosen a range that goes from",
                  input$range[1], "to", input$range[2])
    HTML(paste(str1, str2, sep = '<br/>'))

  })
}
)
)

Note you need to use <br/> as a line break. Also the text you wish to display needs to be HTML escaped so use the HTML function.

9
votes

According to Joe Cheng:

Uhhh I don't recommend using renderUI and htmlOutput [in the way that is explained in the other answer]. You are taking text that is fundamentally text, and coercing to HTML without escaping (meaning if the text just happens to include a string that contains special HTML characters, it could be parsed incorrectly).

How about this instead:

textOutput("foo"),
tags$style(type="text/css", "#foo {white-space: pre-wrap;}")

(Replace the foo in #foo with the ID of your textOutput)

-3
votes

If you mean that you don't care for the line break:

output$text = renderText({
  paste("You have selected ", input$var, ". You have chosen a range that goes 
  from", input$range[1], "to", input$range[2], ".")
})