I'm a newbie in React and I was wondering what is the purpose of registerServiceWorker() in the following code?  import React from 'react'; import ReactDOM from 'react-dom'; import App from './App'; import registerServiceW...

I've inherited a react/node/prismic application where we need to update the prismic-reactjs package, which resulted in needing to update a few others- in total, we changed:  prismic-reactjs: 0.2.0 ? 1.1.0  react: 15.6.1 ? 16.0.0  webpack: 3.12.0...

I'm on a situation where I want to make some dom-node size calculations (top, bottom and size properties of the rendered DOM node)  What I'm doing right now, on the componentDidUpdate method is to call findDOMNode on this:   componentDidUpdat...

I recently upgraded my project from React v15.2.1 to 16.4.1 and my Sidebar component is throwing the following error:  Error: Unable to find node on an unmounted component. bundle.js line 1326 > eval:42:15 invariant webpack:///./node_modules/fbjs/...

I am trying to call a component from another component to display some html and it works if I call the component alone, but if I add more markup inside the same return function, it throws the following error:  Adjacent JSX elements must be wrapped in...

I have been thinking about how to optimize react server side rendering, especially the portion of my app that is the bottleneck, which is the synchronous renterToString invocation. Because this is a blocking call, having long function renderToString...

So I am having trouble implementing this scenario:  From the backend server, I am receving an html string, something along like this:  <ul><li><strong>Title1</strong> <br/> <a class=\"title1" href="title1-...

I have a react-modal which shows some filters. It accepts an isOpen prop which hides or shows the Modal as per the value.  The Modal opens successfully when clicked on 'Apply' button, but does not close on clicking 'Cancel'.  //Click...

If you had 500 components, each with a ref, how would you find which component has the user's focus? All components with a ref are focusable elements like <input />, <textarea />, etc. For simplicity, all of the refs are accessible fr...

import React from 'react'; // import ReactDOM from 'react-dom'; import ReactDOM from 'react-dom/dist/react-dom.min'; import {Alert} from 'reactstrap';  class AlertLine extends React.Component {     constructor(props) {...