Business
Jobs
  • About Us
  • Solutions
    • Job Postings
      Post your job and receive qualified candidates in 48h.
    • Candidate Assessments
      500+ technical and psychological tests, plus anti-fraud.
    • Headhunting
      Tailor-made executive search from start to finish.
    • Payroll + EOR
      Payroll dispersal and EOR across 15+ LATAM countries.
  • Pricing
  • Jobs

0

70
Views
How can I add 'Read more' and 'Read less' functionality for long text in R Shiny?

I am trying to add 'Read more' or 'Read less' functionality for long text in my Shiny app. My knowledge related to JS/ html is limited, so if there is any assist regarding communicating information between shiny, js or html that would be helpful.

I was referring this tutorial but not able to understand how to implement the same in the shiny app.

I was trying with following code.

library(shiny)
library(htmltools)
library(htmlwidgets)

jscode <- 
  'shinyjs.myFunction = function() {
    var dots = document.getElementById("dots");
    var moreText = document.getElementById("more");
    var btnText = document.getElementById("myBtn");

    if (dots.style.display === "none") {
      dots.style.display = "inline";
      btnText.innerHTML = "Read more";
      moreText.style.display = "none";
    } else {
      dots.style.display = "none";
      btnText.innerHTML = "Read less";
      moreText.style.display = "inline";
    }
  }'

css <- "#more {display: none;}"

ui <- fluidPage(
  shinyjs::useShinyjs(),
  shinyjs::extendShinyjs(
    text = jscode,
    functions = c('myFunction')
  ),
  shinyjs::inlineCSS(css),
  uiOutput('test')
)

server <- function(input, output, session) {
  
  output$test <- renderUI({
    
    HTML('<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Phasellus imperdiet, nulla et dictum interdum, nisi lorem egestas vitae scel<span id="dots">...</span><span id="more">erisque enim ligula venenatis dolor. Maecenas nisl est, ultrices nec congue eget, auctor vitae massa. Fusce luctus vestibulum augue ut aliquet. Nunc sagittis dictum nisi, sed ullamcorper ipsum dignissim ac. In at libero sed nunc venenatis imperdiet sed ornare turpis. Donec vitae dui eget tellus gravida venenatis. Integer fringilla congue eros non fermentum. Sed dapibus pulvinar nibh tempor porta.</span></p>

<button onclick="myFunction()" id="myBtn">Read more</button>')
  })
}

shinyApp(ui, server)

Thanks in advance.

about 4 years ago · Juan Pablo Isaza
2 answers
Answer question

0

Here is a possibility:

library(shiny)

CSS <- "
.morecontent span {
    display: none;
}
.morelink {
    display: block;
}
"

JS <- '
$(document).ready(function() {
    // Configure/customize these variables.
    var showChar = 100;  // How many characters are shown by default
    var ellipsestext = "...";
    var moretext = "Show more >";
    var lesstext = "Show less";
    
    $(".more").each(function() {
        var content = $(this).html();
        if(content.length > showChar) {
            var c = content.substr(0, showChar);
            var h = content.substr(showChar, content.length - showChar);
            var html = c + "<span class=\\\"moreellipses\\\">" + ellipsestext 
              + "&nbsp;</span><span class=\\\"morecontent\\\"><span>" + h 
              + "</span>&nbsp;&nbsp;<a href=\\\"\\\" class=\\\"morelink\\\">" 
              + moretext + "</a></span>";
            $(this).html(html);
        }
    });
 
    $(".morelink").click(function(){
        if($(this).hasClass("less")) {
            $(this).removeClass("less");
            $(this).html(moretext);
        } else {
            $(this).addClass("less");
            $(this).html(lesstext);
        }
        $(this).parent().prev().toggle();
        $(this).prev().toggle();
        return false;
    });
});
'

ui <- fluidPage(
  tags$head(
    tags$style(HTML(CSS)), 
    tags$script(HTML(JS))
  ),
  
  tags$span(
    class = "more",
    "Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."
  )
  
)

server <- function(input, output){}

shinyApp(ui, server)

enter image description here

source: codepen.io/maxds/pen/WNrvZY

about 4 years ago · Juan Pablo Isaza Report

0

If you want to avoid JS you could use the details and summary tags in HTML.

Shiny example

Here is a small example implemented using only Shiny-code:

library(shiny)

ui <- fluidPage(

    tags$p("Some information"),
    tags$details(
        tags$summary("Read more"),
        "More information"
    ) 
    
)

server <- function(input, output) {}

shinyApp(ui = ui, server = server)

HTML example

If you want to use HTML directly you could use add this to your server inside the HTML() function in Shiny:

<p>Some information</p>
<details>
  <summary>Read more</summary>
  More information
</details>
about 4 years ago · Juan Pablo Isaza Report
Answer question
Find remote jobs

Discover the new way to find a job!

Top jobs
Top job categories
Business
Post vacancy Pricing Sales
Legal
Terms and conditions Privacy policy
© 2026 PeakU Inc. All Rights Reserved.
Andres GPT
Show me some job opportunities
There's an error!