README.md

In shinyjs: Easily Improve the User Experience of Your Shiny Apps in Seconds

shinyjs

Easily improve the user experience of your Shiny apps in seconds Official website · by Dean Attali

{shinyjs} lets you perform common useful JavaScript operations in Shiny apps that will greatly improve your apps without having to know any JavaScript.

Examples include: hiding an element, disabling an input, resetting an input back to its original value, delaying code execution by a few seconds, and many more useful functions for both the end user and the developer. {shinyjs} can also be used to easily call your own custom JavaScript functions from R.

Need Shiny help? I’m available for consulting. If you find {shinyjs} useful, please consider supporting my work to unlock rewards! ❤

This package is part of a larger ecosystem of packages with a shared vision: solving common Shiny issues and improving Shiny apps with minimal effort, minimal code changes, and straightforward documentation. Other packages for your Shiny apps:

Package Description Demo shinyalert 🗯️ Easily create pretty popup messages (modals) in Shiny 🔗 shinyscreenshot 📷 Capture screenshots of entire pages or parts of pages in Shiny apps 🔗 timevis 📅 Create interactive timeline visualizations in R 🔗 shinycssloaders ⌛ Add loading animations to a Shiny output while it’s recalculating 🔗 colourpicker 🎨 A colour picker tool for Shiny and for selecting colours in plots 🔗 shinybrowser 🌐 Find out information about a user’s web browser in Shiny apps 🔗 shinydisconnect 🔌 Show a nice message when a Shiny app disconnects or errors 🔗 shinyforms 📝 Easily create questionnaire-type forms with Shiny WIP

Table of contents

• Demos and tutorials
• Sponsors 🏆
• Overview of main functions
• Installation
• How to use
• Basic use case - complete working example
• Calling your own JavaScript functions from R
• FAQ and extra tricks
• Support

Demos and tutorials

• Demo Shiny app that lets you play around with some of the functionality in {shinyjs}.
• Video of my {shinyjs} talk (30 min) and the corresponding presentation slides from the 2016 Shiny Developer Conference.
• Video of my {shinyjs} talk (5 min) and the corresponding presentation slides from the 2016 useR Conference.

Sponsors 🏆

There are no sponsors yet

Become the first sponsor for {shinyjs} and unlock special rewards!

Overview of main functions

Note: In order to use any {shinyjs} function in a Shiny app, you must first call useShinyjs() anywhere in the app’s UI.

Function Description show/hide/toggle Display or hide an element (optionally with an animation). hidden Initialize a Shiny tag as invisible (can be shown later with a call to show). enable/disable/toggleState Enable or disable an input element, such as a button or a text input. disabled Initialize a Shiny input as disabled. reset Reset a Shiny input widget back to its original value. refresh Refresh the page. delay Execute R code (including any {shinyjs} functions) after a specified amount of time. alert Show a message to the user. click Simulate a click on a button. html Change the text/HTML of an element. onclick Run R code when a specific element is clicked. Was originally developed with the sole purpose of running a {shinyjs} function when an element is clicked, though any R code can be used. onevent Similar to onclick, but can be used with many other events instead of click (for example, listen for a key press, mouse hover, etc). removeEvent Remove an event that was added to an HTML element with onclick() or onevent(). addClass/removeClass/toggleClass add or remove a CSS class from an element. runjs Run arbitrary JavaScript code. extendShinyjs Allows you to write your own JavaScript functions and use {shinyjs} to call them as if they were regular R code. More information is available in the section “Calling your own JavaScript functions from R” below.

Functions that help you during Shiny app development

Function Description runcodeUI+runcodeServer Adds a text input to your app that lets you run arbitrary R code live. showLog Print any JavaScript console.log() messages in the R console, to make it easier and quicker to debug apps without having to open the JS console. logjs Print a message to the JavaScript console (mainly used for debugging purposes). inlineCSS Easily add inline CSS to a Shiny app.

Check out the {shinyjs} demo app to see some of these in action, or install {shinyjs} and run shinyjs::runExample() to see more demos.

Installation

To install the stable CRAN version:

install.packages("shinyjs")

To install the latest development version from GitHub:

install.packages("remotes")
remotes::install_github("daattali/shinyjs")

How to use

A typical Shiny app has a UI portion and a server portion. Before using most {shinyjs} functions, you need to call useShinyjs() in the app’s UI. It’s best to include it near the top as a convention.

Here is a minimal Shiny app that uses {shinyjs}:

library(shiny)
library(shinyjs)

ui <- fluidPage(
  useShinyjs(),  # Include shinyjs

  actionButton("button", "Click me"),
  textInput("text", "Text")
)

server <- function(input, output) {
  observeEvent(input$button, {
    toggle("text")  # toggle is a shinyjs function
  })
}

shinyApp(ui, server)

This is how most Shiny apps should initialize {shinyjs} - by calling useShinyjs() near the top of the UI.

However, if you use {shinyjs} in any of the following cases:

• In Shiny dashboards (built using the shinydashboard package)
• In Shiny apps that use a navbarPage layout
• In Rmd documents
• In Shiny apps that manually build the user interface with an HTML file or template (instead of using Shiny’s UI functions)

Then you should see the Including {shinyjs} in different types of apps document.

If your Shiny app doesn’t fall into any of these categories, then the above code sample should be enough to get your started with including {shinyjs} in your app.

Basic use case - complete working example

See the {shinyjs} example app walk-through document for a step-by-step guide on how to add a variety of {shinyjs} features to a simple app in order to make it more user friendly.

Calling your own JavaScript functions from R

You can also use {shinyjs} to add your own JavaScript functions that can be called from R as if they were regular R functions using extendShinyjs(). This is only suitable for advanced users who are familiar with JavaScript and wish to facilitate the communication between R and JavaScript.

To learn about this feature and see how useful it can be, see the extendShinyjs: Calling your own JavaScript functions from R document.

FAQ and extra tricks

There are several questions that pop up very frequently in my email or on StackOverflow about “How do I use {shinyjs} to do ___?” Here is a list of a few of these common questions with links to a solution that could be useful. Note that all of these require using extendShinyjs().

• How do I show/hide the shinydashboard sidebar programmatically?
• How do I hide/disable a tab?
• How do I refresh the page?
• How do I call a JavaScript function from a different JavaScript library?
• How do I change the values of a sliderInput?
• How do I call JavaScript code and use the return value?

I also keep a long list of various Shiny tips & tricks for solving common Shiny problems, many of which make use of {shinyjs}.

Support

This document is only an overview of {shinyjs}. There are more in-depth resources available on the {shinyjs} website.

If you need help with {shinyjs}, free support is available on StackOverflow, RStudio Community, and Twitter.

Due to the large volume of requests I receive, I’m unable to provide free support. If you can’t solve any issue and require my personal help, please visit https://xscode.com/daattali/shinyjs or contact me.

Credits

Logo design by Alfredo Hernández.

shinyjs documentation built on Dec. 23, 2021, 5:06 p.m.