Unlock the Power of Interactive Web Apps with Shiny and React
When it comes to building web applications with R, Shiny is a popular choice for rapid prototyping. However, its limitations become apparent when scaling up to more complex solutions. This is where the shiny.react package comes in, allowing you to integrate React with Shiny to create even more sophisticated and interactive components.
Getting Started with Shiny.React
Before diving in, make sure you have a basic understanding of React, Shiny, and their necessary development tools. You’ll also need Node.js and R installed on your system. In this tutorial, we’ll build a simple React app using shiny.react, which will render a select input from the shiny package that listens to user inputs and renders a React component based on the input.
Setting Up the Project
First, install the shiny.react package using the command install.packages("shiny.react") in your R console. Then, load the package into your R session with the expression library(shiny.react). Create a new project folder, and add an app.R file for your Shiny app logic and a data.json file for your dummy data.
Creating the Shiny Backend
In the app.R file, create a Shiny app using the UI and server functions passed as arguments. The UI function renders a Bootstrap page with a navbar, select input, and text. The select input choices are an array of colors that, when selected, is displayed as the textOutput value.
Integrating React with Shiny
To add React code to your Shiny app, you need to create an output that preserves the React state on re-renders and renders the React component in your output. Replace the textOutput with reactOutput, which creates an output that can persist React state. Then, replace the renderText with renderReact, which renders your React component to your reactOutput.
Creating Custom React Components
With the integration done, you can now create custom, reusable React components to include in your Shiny app. Shiny.react offers a method, reactElement, which returns a shiny tag object that represents a React element. You can create a ReactComponent variable that’s a function whose value is a shiny React element.
Adding the React Component to Your Shiny App
Update your app.R file to add the React component to your Shiny app and pass in the required props. Use the jsonlite package to read the data from the JSON file, and then use the data obtained as choices for your input. Update the server function to respond to changes in the value of your select input. The new value is set as the reactive value, which is passed to your React component as a prop.
The Result
Running your application displays a dynamic React component that updates its text and background color based on the user’s input selection. This tutorial demonstrates how to use React in your Shiny apps using the shiny.react package, exploring various methods to include React in your app. By experimenting with different methods, you can decide which ones you prefer to build scalable and interactive Shiny React applications.