React.js: why you should learn the front end JavaScript library and how to get started

React.JS is one of the most powerful JavaScript libraries. It empowers the interface of major organisations such as Amazon (an e-commerce giant has recently introduced a programming language of its own), PayPal, BBC, CNN, and over a million other websites worldwide. Created by Facebook, React.JS has quickly built a daunting technical reputation and a loyal fan following.

Currently React.js is extensively mentioned in job openings – companies want to hire dedicated react.js developer more than Vue.js engineers. In this post, you’ll find out why React.JS is the right framework to start your remote work, despite the library’s steep learning curve and what are the ways to use it more efficiently.

5 Reasons to learn React.JS

Developers might be hesitant to learn React as it’s not a full-fledged framework and a developer needs to handle models and controllers on their own. Nevertheless, there are more than a handful of reasons to become a react js developer. Let’s take a closer look at them:

1. It’s functional

There’s no need to use classes in React. The platform relies heavily on functional components, allowing developers not to overcomplicate the codebase. While classes offer developers a handful of convenient features (using life cycle hooks, and such), the benefits provided by the functional syntax are loud and clear:

• Higher readability. Properties like state functions or lifecycle hooks tend to make reading and testing the code a pain in the neck. Plain JS functions are easier to wrap your head around.
• A developer can achieve the same functionality with less code.
• The software engineering team will more likely adhere to best practices. Stateless functional components encourage front-end engineers to separate presentational and container components. It takes more time to adjust to a more complex workflow – in the long run, it pays off in a better code structure.
• ES6 destructuring helps spot bloated components. A developer can see the list of dependencies bound to every component. As a result, you will be able to break up overly complex structures or rethink them altogether.

React.JS is the tool that recognizes the power of functional components to their fullest extent (even the glorified Angular 2 can’t compare). As a result, developers can strive for maximum code eloquence and improved performance.

2. It’s declarative

Most likely, you are no stranger to CSS and the SQL database programming language, and, as such, are familiar with declarative programming. Still, to recap, here are the differences between declarative and imperative approaches:

Imperative programming uses statements to manipulate the state of the program.

Declarative programming is a paradigm that changes the system based on the communication logic.

While imperative programming gives developers a possibility to design a control flow step-by-step in statements and may come across as easier, it is declarative programming to have more perks in the long run.

• Higher readability. Low-level details will not clutter the code as the paradigm is not concerned with them.
• More freedom for reasoning. Instead of outlining the procedure step-by-step, a successful React JS developer focuses on describing the solution and its logic.
• Reusability. You can apply a declarative description to various scenarios – that is times more challenging for a step-by-step construct.
• Efficient in solving specific domain problems. High performance of declarative programming stems from the fact that it adapts to the domain. For databases, for instance, a developer will create a set of operations to handle data, and so on.

Capitalizing on the benefits of declarative programming is React’s strong point. You will be able to create transparent, reusable, and highly readable interfaces.

3. Virtual DOM

Developers that manage high-load projects often face DOM-related challenges. Bottlenecks tend to appear even after a small change in the document-object-model. Due to the document object model’s tree structure, there’s a high interconnectivity between DOM components.

To facilitate maintenance, Facebook has implemented the virtual DOM in React.JS. It allows developers to ensure the project’s error-free performance before updating an actual DOM tree.

Virtual DOM provides extra assurance in the app’s performance – in the long run, it significantly improves user satisfaction rates.

4. Downward data binding

As opposed to Angular two-way data binding, React.JS uses the downward structure to ensure the changes in child structures will not affect parents. A developer can only transfer data from a parent to a child, not vice versa.

The key components of downward data binding include:

• Passing the state to the child components as well as the view;
• The view triggers actions;
• Actions can update the state;
• State updates are passed on to the view and the child components.

Compared to the two-way data binding, the one implemented by React.JS is not as error-prone (a developer controls data to a larger extent), more comfortable to test and debug due to a clearly defined structure.

5. React Developer Tools

React.JS developers get to benefit from a wide toolkit that covers all facets of the application performance. There’s a wide array of debugging and design solutions, including a life-saving React Developer Tools extension for Chrome and Firefox. Using this and other tools, you can define child and parent components, examine their state, observe hierarchies, and inspect props.

Advantages of React.js

React.JS helps developers systemize the interfaces of their projects by introducing the ‘components’ structure. The library allows the creation of modular views that consist of reusable blocks – pop-ups, tables, etc.

One of the most significant advantages of using React.js is the way it improves user experience. A textbook example of library usage on Facebook is the possibility to see the changing number of likes in real-time without reloading the page.

Originally, React.JS was released back in 2011 by a Facebook engineer as a way to upscale and maintain the complex interface of the Facebook Ads app. The library’s high functionality resulted in its adoption by other SMEs and large corporations – now React JS is one of the most widely used development tools.

How to Use React.JS?

Depending on your HTML and JavaScript proficiency, it may take anywhere from a few days to months to get the hang of React. For the basic understanding of the library, take a look at React.JS features as well as the setup process.

Getting started with React.JS

To start working with React, a developer has to import React and React to DOM libraries using a basic HTML file.

Now that you have set up a working space, take your time to examine the defining features of React.JS.

Components

All React.JS elements are components. Depending on the syntax, they are grouped into the class and functional ones. As, in most cases, both lead to equal outcomes, a React.JS beginner should start by learning functional components.

Props

Props are the way for React.JS developers to pass data from parent to child structures. Keep in mind that, unlike states, props are immutable under any circumstances. They provide developers with high code reusability as the same message will be displayed on all pages.

At times, developers do want components to change themselves. That’s when states come in handy.

States

States are used when a developer wants the application data to change. The most common operations that have to do with states include:

• Initialization;
• Modification;
• Adding event handlers.

These were the basic concepts a React.JS developer has to be familiar with to get the most out of the library.

React.JS best practices

If you’re already using React.JS, be sure to make the most out of it. Keep track of new trends and best practices in all facets of app management – accessibility, performance, security, and others.

Here’s a short collection of React.JS development secret tips that’ll improve the maintenance and development efficiency.

Performance:

Consider using React.Fragment to avoid extra DOM nodes. To load components on-demand, use React.Lazy, along with React.Suspense. Another popular practice among JS developers is taking advantage of shouldComponentUpdate to avoid unnecessary rendering.

Try to keep the JS code as clean as possible. For instance, delete the DOM components you don’t use with ComponentDidUnomunt (). For component caching, use React.Memo.

Accessibility

Pay attention to the casing and reserved word differences in HTML and React.js to avoid bottlenecks. To set up page titles, use the react-handle plugin to set up page titles.

Don’t forget to put ALT-tags for any non-text content. Use ref() functions to pinpoint the focus on a given component. External tools like ESLint plugin help developers monitor accessibility.

Debugging

Use Chrome Dev Tools – there are dozens of features – reduct logger, error messages handler, and so on. Leave the console open while coding to detect errors faster.

To have a better understanding of the code you’re dealing with, adopt a table view for objects. Other quick debugging hacks include marking DOM items to find them quickly in a Google Chrome Inspector. View full stack traces for functions.

The bottom line

Thanks to a powerful team of engineers at work, React.JS has quickly become a powerhouse for front end development. Its huge reliance on JavaScript makes a library easier to get to know.

While React.JS pros and cons are extensive – however, the possibility to express UIs declaratively along with the promotion of functional components makes it a favorite framework for many. A wide variety of the projects it empowers and a large number of job openings prove that knowing React is no longer optional for developers.

The good news, there’s no lack of learning tools and resources online. Take your time to explore the library – you’ll be amazed by the order and efficiency React brings to applications.