This content originally appeared on DEV Community and was authored by DEV Community
This is a series of memos referring to the ways of React state management: context API, Redux and Redux toolkit. The topic in this article is Redux.
The chart below is the whole image of this practice application. ComponentA accepts user input text and passes it over to ComponentB as a prop. At the same time, dispatch the action to save the data in the store so that ComponentC and componentD can use it.
Redux Fundamentals, Part 1: Redux Overview | Redux
This is the image of this application.
This is the structure of files in src folder.
1) Set up types, actions, reducers, and store
First of all, you need to install redux and react-redux.
npm install redux react-redux
types
export const SUBMIT = "SUBMIT";
actions
import { SUBMIT } from "./types";
export const submit = (text) => ({
type: SUBMIT,
payload: text,
});
reducer
import { SUBMIT } from "./types";
const INIT_STATE = {
text: null,
};
const reducer = (state = INIT_STATE, action) => {
if (action.type === SUBMIT) {
return {
text: action.payload,
};
} else {
return state; //provide the default action to return state which redux uses when initialization
}
};
export default reducer;
store
import { createStore } from "redux";
import reducer from "./reducer";
const store = createStore(reducer);
export default store;
2) Provider
index.js
import React from "react";
import ReactDOM from "react-dom";
import "./index.css";
import App from "./App";
import { Provider } from "react-redux";
import store from "./redux/store";
ReactDOM.render(
<Provider store={store}>
<App />
</Provider>,
document.getElementById("root")
);
3) useDispatch, useSelector
ComponentA
import { useState } from "react";
import { useDispatch } from "react-redux";
import { submit } from "../redux/actions";
import ComponentB from "./ComponentB";
const ComponentA = () => {
const [value, setValue] = useState("");
const dispatch = useDispatch();
const changeHandler = (e) => {
setValue(e.target.value);
dispatch(submit(e.target.value));
};
return (
<>
<input type="text" value={value} onChange={changeHandler} />
<ComponentB text={value} />
</>
);
};
export default ComponentA;
ComponentC
import { useSelector } from "react-redux";
const ComponentC = () => {
const text = useSelector((state) => state.text);
return (
<>
<h1>Uppercase</h1>
<h2>{text && text.toUpperCase()}</h2>
</>
);
};
export default ComponentC;
ComponentD
import { useSelector } from "react-redux";
const ComponentD = () => {
const text = useSelector((state) => state.text);
return (
<>
<h1>Lowercase</h1>
<h2>{text && text.toLowerCase()}</h2>
</>
);
};
export default ComponentD;
The whole code is available here
Thank you for reading :)
The original article is here
This content originally appeared on DEV Community and was authored by DEV Community

DEV Community | Sciencx (2022-03-07T06:45:05+00:00) React State Management (2) : Redux. Retrieved from https://www.scien.cx/2022/03/07/react-state-management-2-redux/
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