React
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/ Git - Gitlab | GitHub, SprUng, LEARN, React, TOOLS / 11 minutes of reading

Animation Add-Ons

https://reactjs.org/docs/animation.html

React Transition Group examples and tutorial

 

Installing react – transition

To install React Transition Group, run these commands in the terminal:



# npm
npm install react-transition-group --save

# yarn
yarn add react-transition-group

Next, we’ll take a detailed look at the components available with React Transition Group and go over some practical react-transition-group examples.

 

If you haven’t worked with JavaScript in the last few years, these three points should give you enough knowledge to feel comfortable reading the React documentation:

  • We define variables with and statements. For the purposes of the React documentation, you can consider them equivalent to .
  • We use the class keyword to define JavaScript classes. There are two things worth remembering about them. Firstly, unlike with objects, you don’t need to put commas between class method definitions. Secondly, unlike many other languages with classes, in JavaScript the value of this in a method depends on how it is called.
  • We sometimes use => to define “arrow functions”. They’re like regular functions, but shorter. For example, x => x * 2 is roughly equivalent to function(x) { return x * 2; }. Importantly, arrow functions don’t have their own this value so they’re handy when you want to preserve the this value from an outer method definition.

Don’t worry if this is too much to take in at once. The MDN JavaScript Reference is a stellar resource, and you can consult it whenever you get confused by something.

Also, when you feel unsure about what some newer syntax means, you can use the Babel REPL with the ES2015 preset to check what equivalent older syntax it compiles to.

 

 

Create a New React App

Use an integrated toolchain for the best user and developer experience.

This page describes a few popular React toolchains which help with tasks like:

  • Scaling to many files and components.
  • Using third-party libraries from npm.
  • Detecting common mistakes early.
  • Live-editing CSS and JS in development.
  • Optimizing the output for production.

The toolchains recommended on this page don’t require configuration to get started.

You Might Not Need a Toolchain

If you don’t experience the problems described above or don’t feel comfortable using JavaScript tools yet, consider adding React as a plain “ tag on an HTML page, optionally with JSX.

This is also the easiest way to integrate React into an existing website. You can always add a larger toolchain if you find it helpful!

The React team primarily recommends these solutions:

  • If you’re learning React or creating a new single-page app, use Create React App.
  • If you’re building a server-rendered website with Node.js, try Next.js.
  • If you’re building a static content-oriented website, try Gatsby.
  • If you’re building a component library or integrating with an existing codebase, try More Flexible Toolchains.

Create React App

Create React App is a comfortable environment for learning React, and is the best way to start building a new single-page application in React.

It sets up your development environment so that you can use the latest JavaScript features, provides a nice developer experience, and optimizes your app for production. You’ll need to have Node >= 10.16 and npm >= 5.6 on your machine. To create a project, run:

npx create-react-app my-app
cd my-app
npm start

Note

npx on the first line is not a typo — it’s a package runner tool that comes with npm 5.2+.

Create React App doesn’t handle backend logic or databases; it just creates a frontend build pipeline, so you can use it with any backend you want. Under the hood, it uses Babel and webpack, but you don’t need to know anything about them.

When you’re ready to deploy to production, running npm run build will create an optimized build of your app in the build folder. You can learn more about Create React App from its README and the User Guide.

Next.js

Next.js is a popular and lightweight framework for static and server‑rendered applications built with React. It includes styling and routing solutions out of the box, and assumes that you’re using Node.js as the server environment.

Learn Next.js from its official guide.

Gatsby

Gatsby is the best way to create static websites with React. It lets you use React components, but outputs pre-rendered HTML and CSS to guarantee the fastest load time.

Learn Gatsby from its official guide and a gallery of starter kits.

More Flexible Toolchains

The following toolchains offer more flexibility and choice. We recommend them to more experienced users:

  • Neutrino combines the power of webpack with the simplicity of presets, and includes a preset for React apps and React components.
  • Nx is a toolkit for full-stack monorepo development, with built-in support for React, Next.js, Express, and more.
  • Parcel is a fast, zero configuration web application bundler that works with React.
  • Razzle is a server-rendering framework that doesn’t require any configuration, but offers more flexibility than Next.js.

Creating a Toolchain from Scratch

A JavaScript build toolchain typically consists of:

  • A package manager, such as Yarn or npm. It lets you take advantage of a vast ecosystem of third-party packages, and easily install or update them.
  • A bundler, such as webpack or Parcel. It lets you write modular code and bundle it together into small packages to optimize load time.
  • A compiler such as Babel. It lets you write modern JavaScript code that still works in older browsers.

If you prefer to set up your own JavaScript toolchain from scratch, check out this guide that re-creates some of the Create React App functionality.

Don’t forget to ensure your custom toolchain is correctly set up for production.

 

Release Channels

React relies on a thriving open source community to file bug reports, open pull requests, and submit RFCs. To encourage feedback we sometimes share special builds of React that include unreleased features.

This document will be most relevant to developers who work on frameworks, libraries, or developer tooling. Developers who use React primarily to build user-facing applications should not need to worry about our prerelease channels.

Each of React’s release channels is designed for a distinct use case:

  • is for stable, semver React releases. It’s what you get when you install React from npm. This is the channel you’re already using today. Use this for all user-facing React applications.
  • tracks the master branch of the React source code repository. Think of these as release candidates for the next minor semver release. Use this for integration testing between React and third party projects.
  • includes experimental APIs and features that aren’t available in the stable releases. These also track the master branch, but with additional feature flags turned on. Use this to try out upcoming features before they are released.

All releases are published to npm, but only Latest uses semantic versioning. Prereleases (those in the Next and Experimental channels) have versions generated from a hash of their contents, e.g. 0.0.0-1022ee0ec for Next and 0.0.0-experimental-1022ee0ec for Experimental.

The only officially supported release channel for user-facing applications is Latest. Next and Experimental releases are provided for testing purposes only, and we provide no guarantees that behavior won’t change between releases. They do not follow the semver protocol that we use for releases from Latest.

By publishing prereleases to the same registry that we use for stable releases, we are able to take advantage of the many tools that support the npm workflow, like unpkg and CodeSandbox.

Latest Channel

Latest is the channel used for stable React releases. It corresponds to the latest tag on npm. It is the recommended channel for all React apps that are shipped to real users.

If you’re not sure which channel you should use, it’s Latest. If you’re a React developer, this is what you’re already using.

You can expect updates to Latest to be extremely stable. Versions follow the semantic versioning scheme. Learn more about our commitment to stability and incremental migration in our versioning policy.

Next Channel

The Next channel is a prerelease channel that tracks the master branch of the React repository. We use prereleases in the Next channel as release candidates for the Latest channel. You can think of Next as a superset of Latest that is updated more frequently.

The degree of change between the most recent Next release and the most recent Latest release is approximately the same as you would find between two minor semver releases. However, the Next channel does not conform to semantic versioning. You should expect occasional breaking changes between successive releases in the Next channel.

Do not use prereleases in user-facing applications.

Releases in Next are published with the next tag on npm. Versions are generated from a hash of the build’s contents, e.g. 0.0.0-1022ee0ec.

Using the Next Channel for Integration Testing

The Next channel is designed to support integration testing between React and other projects.

All changes to React go through extensive internal testing before they are released to the public. However, there are a myriad of environments and configurations used throughout the React ecosystem, and it’s not possible for us to test against every single one.

If you’re the author of a third party React framework, library, developer tool, or similar infrastructure-type project, you can help us keep React stable for your users and the entire React community by periodically running your test suite against the most recent changes. If you’re interested, follow these steps:

  • Set up a cron job using your preferred continuous integration platform. Cron jobs are supported by both CircleCI and Travis CI.
  • In the cron job, update your React packages to the most recent React release in the Next channel, using next tag on npm. Using the npm cli: 
    npm update react@next react-dom@next

    Or yarn:

    yarn upgrade react@next react-dom@next
  • Run your test suite against the updated packages.
  • If everything passes, great! You can expect that your project will work with the next minor React release.
  • If something breaks unexpectedly, please let us know by filing an issue.

A project that uses this workflow is Next.js. (No pun intended! Seriously!) You can refer to their CircleCI configuration as an example.

Experimental Channel

Like Next, the Experimental channel is a prerelease channel that tracks the master branch of the React repository. Unlike Next, Experimental releases include additional features and APIs that are not ready for wider release.

Usually, an update to Next is accompanied by a corresponding update to Experimental. They are based on the same source revision, but are built using a different set of feature flags.

Experimental releases may be significantly different than releases to Next and Latest. Do not use Experimental releases in user-facing applications. You should expect frequent breaking changes between releases in the Experimental channel.

Releases in Experimental are published with the experimental tag on npm. Versions are generated from a hash of the build’s contents, e.g. 0.0.0-experimental-1022ee0ec.

What Goes Into an Experimental Release?

Experimental features are ones that are not ready to be released to the wider public, and may change drastically before they are finalized. Some experiments may never be finalized — the reason we have experiments is to test the viability of proposed changes.

For example, if the Experimental channel had existed when we announced Hooks, we would have released Hooks to the Experimental channel weeks before they were available in Latest.

You may find it valuable to run integration tests against Experimental. This is up to you. However, be advised that Experimental is even less stable than Next. We do not guarantee any stability between Experimental releases.

How Can I Learn More About Experimental Features?

Experimental features may or may not be documented. Usually, experiments aren’t documented until they are close to shipping in Next or Latest.

If a feature is not documented, they may be accompanied by an RFC.

We will post to the React blog when we’re ready to announce new experiments, but that doesn’t mean we will publicize every experiment.

You can always refer to our public GitHub repository’s history for a comprehensive list of changes.

 

 

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