Introduction Global state or shared state is one of the biggest issues when you start developing a React app. Should we use Redux? Do hooks provide a Redux-like solution? I would like to show four patterns toward using Redux. This is my personal opinion and mainly for new apps. Pattern 1: Prop passing Some might think it wouldn’t scale, but the most basic pattern should still be prop passing. If the app is small enough, define local state in a parent component and simply pass it down to child components. ... Read More

Introduction Recently, React Redux released hooks API. It’s v7.1.0-alpha.4 as of writing. https://github.com/reduxjs/react-redux/releases/tag/v7.1.0-alpha.4 On the other hand, I’ve been developing a new React Redux binding library with hooks and Proxy. https://github.com/dai-shi/reactive-react-redux It’s time to benchmark both of them to have better understanding in performance. The reactive-react-redux library utilizes Proxy to auto-detect state usage, hence it technically has overhead which would affect performance. We would like to learn how much it will be affected in a realistic example. ... Read More

Introduction React Redux is one of popular web tech stacks. As I found React hooks so promising, I have been developing a hooks-based library for React Redux called “reactive-react-redux.” https://github.com/dai-shi/reactive-react-redux Coding style using this library is mentally different from the official react-redux. Thanks to Proxy, developers don’t need to care about optimization, but just focus on composition of logic. This library provides two basic hooks: useReduxState and useReduxDispatch. This article shows example code how to use them. ... Read More

This short article shows code examples how hooks are analogous to components in terms of composition. Without a word, let’s jump in the code. React components Let’s use a minimalistic example. Here’s a component. const Person = ({ person }) => ( <div> <div className="personFirstName"> <span>First Name:<span> <span>{person.firstName}</span> </div> <div className="personLastName"> <span>Last Name:<span> <span>{person.lastName}</span> </div> </div> ); Well, this component is a little bit big, so let’s split it into functions and compose them. ... Read More

Background React 16.8 added a new API, Hooks. If you haven’t learned hooks yet, go to the official site and read the entire document before continuing this article. https://reactjs.org/docs/hooks-intro.html Hooks are a new addition in React 16.8. They let you use state and other React features without writing a class. This… reactjs.org This article is about how to create custom hooks for data fetching. As described in the roadmap, React is planning to release react-cache and Suspense for data fetching in the near future. ... Read More

Introduction According to React 16.x Roadmap, we are expecting Concurrent Mode soon. React 16.x (~Q2 2019): The One with Concurrent Mode Concurrent Mode lets React apps be more responsive by rendering component trees without blocking the main thread. It is opt-in and allows React to interrupt a long-running render (for example, rendering a new feed story) to handle a high-priority event (for example, text input or hover). Concurrent Mode also improves the user experience of Suspense by skipping unnecessary loading states on fast connections. ... Read More

Introduction While I don’t feel like coding React without hooks, react-cache still seems to be still far away. Surely, caching in data fetching important, nevertheless I would like to seek possibilities of implementations only with React Hooks. These might be obsoleted in the future, but I want something today, that is “useFetch”. This could be still useful without react-cache in case sophisticated caching is not necessary. I’ve started developing “useFetch” as a tutorial to build a custom hook. ... Read More

Introduction React Hooks is something I’ve been working on lately. What’s wonderful is creating custom hooks. If you encapsulate logic nicely in a hook, it can be shared among components and used intuitively. You can find my custom hooks in my GitHub repos, some of which are very experimental. This time, my experiment is to combine React Hooks and Web Workers. I know it’s not too difficult, but let me explain a bit in this short article. ... Read More

Introduction One of the technologies we should keep eyes on in the web world is WebAssembly or wasm. As I am new to it, I won’t describe much of its fundamentals. Please visit the official web site to learn from scratch. https://webassembly.org/ This short article describes my first trial on wasm. What I want to try is just to run example code, but I’d start with writing the example code in wasm(wat). ... Read More

Introduction It’s been about a year since React Context API is out. This is powerful and it’s even more powerful with upcoming React Hooks API, namely useContext. Please check out official documents to learn them in detail. https://reactjs.org/docs/context.html https://reactjs.org/docs/hooks-intro.html Now, this very short article is just about the default value of a context. When you create a context, you pass a default value in the first argument. The defaultValue argument is only used when a component does not have a matching Provider above it in the tree. ... Read More