The main aim of ReactJS is to be fast, scalable, and simple. Developers can easily create complex web applications with ease. It’s the go-to solution for any developer because of its main feature i.e. it can dynamically change the view without the need of reloading the web page. This change happens on the basis of DOM.
You might be amazed by some of the big shot companies that use ReactJS: WhatsApp, Netflix, New York Times, Yahoo mail, Dropbox, Khan Academy, CodeAcademy, and many more.
And if you are one of them, then this is the right blog as we are going to discuss some of the valuable tips you can follow to improve your ReactJS performance.
Note: This blog is the outcome of our writers annoyingly asking a million questions to our developers. They now hate us but we are sure you’ll love the blog 🙂
Use immutable data structures
It is wise to set immutable data structures as they make copies of objects.
Yes, you heard it right!
With the help of data alterations, you can make a copy of objects instead of changing the whole object. This will make the task of detecting changes easy.
Remove extra source code
React is one of the best features is that it automatically warns developers when their code might have bugs or errors. This is very helpful but can decrease your application’s performance.
To solve this problem, you can delete the line (process.env.NODE_ENV != ‘production’) from the source code of React.
Note: While deleting this make line, make sure that you are deleting it properly. If not done properly, there are chances that your app might crash.
Virtualize long lists
Many times, when you have to display long lists or tables on the website, there are possibilities that they will take a longer time to load. This is where virtualizing long lists comes to your rescue.
List virtualization or windowing will render only data that is useful to your user. The numbers of elements that it renders initially are very small. The window of visible content loads when the user scrolls down the website. This will improve the rendering and scrolling performance of your website. You’ll need a package to implement the Virtual long list. You can use already built React libraries like react-window and react-virtualized by Brian Vaughn.
Use constant and inline elements
React Constant Elements treats JSX elements like values, moves them to high scope, and reduces calls to React.createClass. React Inline Elements helps by setting the goal by converting JSX elements into object literals.
To set this, add the following configuration to your package.json file:
Use Gzip or Brotli compression
Many times, heavy files make it difficult to load the website faster. This results in slow loading of the websites and often users leaving it. If your website loading speed isn’t 3s or less, then chances are 80% of the visitors will close the tab then and there.
To not let this happen, you can enable Gzip or Brotli on your web server. They are compression types and can reduce the client’s data usage, and improve the render time of your website.
React developer tools
ReactJS provides developers with React Developer Tools which are available as a chrome extension. This extension highlight component which helps you know if any unwanted rendering cycles are going on.
Once you install the extension, open it, and select the React tab in Chrome Dev Tools, check the “Highlight Updates” box and start working on your project. As you start working on a project, the component will re-render and will get highlighted either in blue, red, green, or yellow color. The light colors represent components that update less while warm colors indicate frequent updates.
Hence, you should see lots of yellow and red UI elements like sliders. When you click on the button and if it turns into a red color, then it means that some unnecessary rendering is happening in the background.
Using reselect selectors
Using reselect optimizes Redux state management. It practices immutability which means that new object reference gets created every time on action dispatch. This obstructs the performance because rerendering will be triggered on components when object reference changes whereas the fields haven’t changed.
The Reselect library uses Redux state and checks the field state. Further, it tells the react to render if field values have changed or not. Hence, reselect saves time by traversing through the previous and current Redux state fields.
It checks if there is a change in spite of having different memory. If fields have changed, it tells React to re-render. If fields are not changed, then it cancels the re-rendering even if new state objects are created. The concept of reselect selectors too depends on immutable data structures.
ReactJS development has taken the developer world by storm because of its features and ease it provides to developers. It is one of the great products by Facebook, ironically. And comes with lots of features to make development fun and easy.