react-transition-group 
ATTENTION! To address many issues that have come up over the years, the API in v2 and above is not backwards compatible with the original
React addon (v1-stable).For a drop-in replacement for
react-addons-transition-groupandreact-addons-css-transition-group, use the v1 release. Documentation and code for that release are available on thev1-stablebranch.We are no longer updating the v1 codebase, please upgrade to the latest version when possible
A set of components for managing component states (including mounting and unmounting) over time, specifically designed with animation in mind.
Documentation
TypeScript
TypeScript definitions are published via DefinitelyTyped and can be installed via the following command:
npm install @types/react-transition-group
Examples
Clone the repo first:
git@github.com:reactjs/react-transition-group.git
Then run npm install (or yarn), and finally npm run storybook to start a storybook instance that you can navigate to in your browser to see the examples.