This document provides an introduction to developing universal JavaScript applications using React, Redux, and TypeScript. It explains the core concepts of React components, the importance of managing state, and how Redux serves as a predictable state container to enhance application consistency. The document also highlights tools and middleware within the Redux ecosystem, along with resources for further exploration.
React + Redux+ TypeScript === ♥
An introduction to the development of universal JavaScript
applications with React, Redux & TypeScript
By Remo H. Jansen
2.
Live demo &source code
https://github.com/remojansen/typescript-redux-react-demo
3.
React
A JavaScript libraryfor building user interfaces.
Lots of people use React as the V in MVC.
Makes no assumptions about the rest of your technology stack.
Abstracts away the DOM from you.
Can also render on the server using Node.
Can power native apps using React Native.
One-way reactive data flow.
4.
React.Component
Components are themain building block of a React application.
A component represents a self-contained piece of UI.
Display some data and be able handle some kind of user interaction.
A component can contain child components.
Everything is atree!
Properties (JSON):
Components (JSX/TSX)
Output (HTML)
8.
React.Component: State, JSX/TSXand Events
The state starts with a default value when a Component mounts.
The state suffers from mutations in time (mostly generated from user events).
A Component manages its own state internally (you could say the state is private).
9.
React.Component: The stateproblem
The Problem:
Managing the internal state of the components makes them hard to maintain.
Components stop being a “pure function” when we use state: (porps) => HTML
The solution:
Move the state to the parent component and inject it as properties.
Inject properties from the top of the component’s hierarchy.
10.
Redux
Predictable state containerfor
JavaScript apps.
Applications that behave
consistently.
Run in client, server, and native
easy to test.
Great developer experience.
Unidirectional data flow.
Making the state“global”: The provider
The provider owns the store and makes the it
available to other components (in the
component hierarchy below) using the
@connect() calls.
13.
Redux: @Connect
Components decoratedwith @connect
are aware of the Store and because of
that we call them smart components.
Dumb components receive their
properties from its parent component
and are not aware of the Store.
Smart components are less reusable.
14.
Redux: Actions andaction creators
An action creator is just a function that returns an action (a JSON object). Actions
must have an action type:
Using the makeActionCreator helper:
15.
Redux: Reducers
Actions describethe fact that something happened, but don’t specify how the
application’s state changes in response. This is the job of a reducer.
(Previous State, Action) => new
State
#5 Think about an online chess game made in HTML. Think about one of the cells in the game board.
The cell represents a self-contained piece of UI and therefore can be implemented as a React component.
We could represent the cell and a contained figure using the following HTML.
That HTML is going to be generated by a React component.