React.JS - Front end Javascript Framework

React.JS -  Front end Javascript Framework, One of the revolutionary tools for front-end web development is called React JS. It is an interactive user interface (UI) based JavaScript framework that can be used to build web and mobile apps very quickly.

ReactJS is built on an open-source platform; More component rich libraries.  With which the view layer of web and mobile applications (front-end) can be developed very easily. The Model View Controller (MVU) framework defines how your app will look.

Fast, secure and scalable apps are constantly being developed with React.  React JS provides users and developers with an experience not commonly seen in other frameworks. So if you are worried about which framework to use for your next project, I would say you can safely choose React JS (*conditional).

React.JS -  Front end Javascript Framework

React JS is an open source JavaScript library developed and maintained by Facebook. Without extensive coding knowledge, rich and engaging web applications can be built using React JS.  The main purpose of React JS is to offer the best possible rendering performance.  Mainly programmers like it because it has mastery over individual components. It helps the user to extend the complex UI to more specific segments.

What is ReactJS?

It is a popular JavaScript framework used for user interface development.  A software engineer is reluctant to call it a “framework” because it gives developers freedom, speed of work, accurate code and special features that other frameworks fail to offer.

ReactJS is a flexible, declarative and efficient JavaScript library. It is a component-based front-end library that can be used to create just one application's view layer.

Back History-

Facebook engineer "Jordan Walke" wants to add a new dimension to modern UI development with React JS. When he went to build a client side application he found that the DOM (Document Object Model) was slowing down for some reason. He noticed this while adding HTML and XML files to the app's API (Application Programming Interface). 

He developed React JS by strengthening the foundation of logical structure.He first introduced React JS in 2012. He saw great success using React JS instead of HTML5 in earlier apps. And officially in 2013 it was opened and made open-source by Facebook authorities.

Why ReactJS is the top choice for developers?

First of all, it is an open-source platform so it has already gained great acceptance among all developers. React allows you to create dynamic applications that perform a significant amount of browser functionality and allow developers to work without connecting to the server.

This allows the developer to independently provide data and interfaces to the application.Compared to other well-known frontend frameworks like 'Angular' and 'Vue.js', React is remarkably easy to understand. This is one of the primary explanations for why React quickly became so popular. It helps organizations to build projects faster.

The ReactJS framework helps developers create user interfaces (UI). On-screen menus, searchbars, buttons, and all other elements of UI help establish the relationship between a website and a web application.

Before ReactJS came along, developers used “vanilla JavaScript” or “Jquery” to design UI, which was time-consuming and full of errors and bugs.

With reusable React library code helps in faster development and less errors in coding. And it has become very popular among developers because of the user interface design which is awesome and fast.

Also,

-Code reduction in React JS is done as snippets and components.

-JSX options manipulate the DOM directly.

-Virtual DOM is very helpful in increasing web site performance.

That's why all websites developed with React are incredibly fast. This is one of the reasons why developers love React.

The current popularity of ReactJS in front-end web development is skyrocketing.

Creating dynamic applications is very easy-

Building dynamic applications used to be difficult but React has made it very easy.  It requires less coding and is much more efficient.

High performance applications can be created by:

Since React uses a virtual DOM, application performance and speed are relatively high.  One of the reasons for this is that all components are uploaded in moments and can execute immediately.

Components can be used multiple times:

React's components work together to form a block that is used in different parts of the application.  React changes the component according to the logic, so that the user gets the best performance and complex front-end actions are done very easily.

One-way data flow-

ReactJS always has a one-way data flow.  That means, when a React app is designed, the connection between the parent and child components needs to be created. By doing this, various errors can be debugged very easily. And if a bug is found, it can be fixed quickly.

Web and mobile app development can be done with React-

I have already said that web apps are developed with React.  But not only that, it can also be used to develop beautiful mobile apps.  There is a framework called React Native which makes mobile app development very easy.  And it supports all platforms simultaneously.

Easy to debug-

Facebook has developed a Chrome extension that makes debugging React very easy.  It makes debugging process of React web application much easier and faster.

Three React terms that you need to know are-

There are three expressions in React that you know will give you a little idea about React.

Components : Components are arranged in the form of blocks that help to keep all the elements of the application together. Custom components can be built in React, which helps to build a complete UI library and connect with custom logic.

JSX: JSX is a syntax extension to JavaScript. It is mainly used in React to beautify the UI. At the same time, it works much like a template engine, enabling full JavaScript. JSX does a great job of rendering React elements within the DOM. It's a JavaScript extension that combines HTML and XML syntax control and logic for developers.

Redux: This is a state management library that brings code under the Variant ecosystem. Redux helps application code to be consistent and run in different environments (ie: client, server and native).  And the most interesting feature of Redux is that it allows live code editing.

Let's know about some giant apps built with React-

Think about Facebook first. Facebook first used React in 2012. It was very challenging to give ads and manage the social network on Facebook. Facebook then moved away from HTML5 to React and was able to deliver a stunning mobile and web user interface (UI).

Later, the company achieved great success by using it on Instagram. In addition, many other big companies have used React JS in their web apps and mobile apps. Among them the applications are:

Social networking applications

  Facebook

  Instagram

  Printerrest

  Twitter

  Reddit

Media sites

  Yahoo!  (Their mail client is developed    with React)

  The New York Times

 

Video platform

  Netflix

 SaaS (Software as a Service)

  Dropbox

  sendgrid

  asana

  InvisionApp

  Zapier

 

other special

  Microsoft

  ebay

Sharing platform

  Airbnb

  Lyft

  Uber

How does React work?

Now let's go a little deeper. We generally use JavaScript along with HTML, CSS on the website. Now the browser creates a dom tree behind the scenes so that the user can interact with that dom. This process in the browser is called the critical render path [].

See the processes here. In this way a DOM is created by passing each step. Then a webpage is displayed in front of us. But we know JavaScript can manipulate DOM. So if you manipulate the DOM of a page that has been rendered complete with JavaScript, that webpage is completely rendered again (except for the two latest browsers, most of the browsers create a new DOM tree and render again), which takes time. And so if a page has too much JavaScript to manipulate the DOM, that webpage will become slow. So here is the real game of React.

What does React do?

React creates another DOM similar to the DOM of this browser, which is called virtual DOM. Now this DOM looks exactly like the real DOM, but this virtual DOM is actually a JavaScript object. React makes it so that any element can be modified quickly and efficiently using JavaScript with this DOM.

Now here also React does another thing.  React creates not one but two virtual domains.But why two? Yes, here is the trick. When the user takes an action within the React app, or what we call a change to the DOM, React stores those changes in one of two virtual DOMs, and the other contains the previous version. Now compare the old with the new one by looking at React and see which specific elements have been changed. Accordingly, React changes only what has changed, rather than re-rendering or re-painting the entire DOM. It works easily and quickly and the browser does not have to do any additional, unnecessary work.

And thus, React can render so fast using this technique.Depends on what you want to do with React or how far you want to run with ReactJS. But in my opinion, before anyone comes to learn React, he should get his hands on the following things, otherwise he will get stuck in the middle.

-Class 

-Modules (import , export)

-Template Literals

-Inheritance

-Data Types , Type Casting

-Constructor , Member variable , Member function

-In Depth concept of null and undefined

-Difference between let , var and const

-Array.forEach() , Array.map() , Function.call() , Function.apply() , Function.bind() and similar Functions/Properties

-Block scoping & Hoisting

-Working with keyword this

-Object manipulation

-Arrow function

-Rest and spread operator

-Exception handling

-String manipulation

-Callbacks

-Asynchronous programming

-Associative array , for-in loop , Map , WeakMap , Set , WeakSet

-Promise

-Working with events , event propagation & delegation , bubbling, capturing

-Fetch for consuming APIs

If you know this, hopefully you won't get stuck and then when you get your hands on React, you will understand yourself where you are lacking or what you need to learn.

How to Install ReactJS:

To install ReactJS we need "Node.js." Node.JS is an essential platform for ReactJS development.

After successfully installing NodeJS, we can start the work of setting up React on top of it using NPM.

Read more: Node.js Even- Driven Programming

Node.js download link "https://nodejs.org/en/download"

You can install ReactJS in two ways:

Using "Webpack" and "Babel".

Using the "create-react-app" command.

You can install ReactJS more easily by installing 'create-react-app' without using webpack and Babel.

 Step 1 – Install create-react-app

Browse through desktop and install create-react-app using command prompt as below –

 C:\Users\Satt>cd C:\Users\Satt\Desktop\

 C:\Users\Satt\Desktop>npx create-react-app my-app

This will create a folder called "my-app" on the desktop and install all the required files in it.

 Step 2 – Delete all source files

Browse to the files. folder in the generated "My-app" folder and remove all files from it as below-

 -

 C:\Users\Satt\Desktop>cd my-app/src

 C:\Users\Satt\Desktop\my-app\src>del *

 C:\Users\Satt\Desktop\my-app\src\*, Are you sure (Y/N)?  y

Step 3 – Add files

Add files named "index.css" and "index.js" to "src" folder –

 -

 C:\Users\Satt\Desktop\my-app\src>type nul > index.css

 C:\Users\Satt\Desktop\my-app\src>type nul > index.js

 Add the following code to the index.js file.

 import React from 'react';

 import ReactDOM from 'react-dom';

 import './index.css';

Step 4 – Run the project

Finally, run the project using the start command.

 'npm start'

Limitations of ReactJS:

Covers only the view layer of the application, so you need to take help of other technologies to define a complete toolset for development.

Uses inline templating and JSX which may seem awkward to some developers.

Future of React-

There must be a reason why ReactJS is so popular. It is the world's most popular and in-demand web framework according to the Stack Overflow Developer Survey 2019 report. Stackover flow shows trends in React. Last 5 years trends of searching on React topic in Google.

Read more :ReactNative features and work

React JS developers earn much more than other web developers. Many comment that React JS may dominate the entire web development industry in the future due to the rapid introduction and emergence of apps.

Conclusion:Many companies are migrating to ReactJS and have already started using it to build many new projects. So all junior and senior developers are learning it and doing new projects.

Facebook and other organizations are working to keep it consistent and secure.  In order to keep ReactJS more flexible, scalable and safe. Along with this, some communities have been formed who are simultaneously working with this technology.Day by day it is getting easier and easier to use. So if you want to avoid all kinds of complexity, you can use React in your next front-end project.