react-global-hook

Easy state management for react & react-native using hooks. it's useful for global state management and complex components state

React-global-hook V2 uses the React.context

TOC

• Install
• Create Store
• Class Components
• create Local Store
• Store
• Performance
• Stories
• Examples

Install

npm i react-global-hook@next --save

yarn add react-global-hook@next

createStore

import { createStore, createHooks, Provider } from "react-global-hook";

const initialState = {
  counter: 0,
};

const actions = ({ setState, getState }) => ({
  increase() {
    const { count } = getState()
    setState({ count: count + 1 });
  },
  decrease() {
    const { count } = getState()

    if (count <= 0) return;

    setState({ count: count - 1 });
  },
});

/**
 * The initializer run when Provider render
 */
const initializer = (state) => ({
  ...state
  counter: new Date().getDay()
})

const store = createStore(initialState, actions, initializer);
const useGlobal = createHooks(store);

const OtherComp = () => {
  const [state, actions] = useGlobal(["counter"]); // Will update based on changes to counter

  return <p>Count:{state.counter}</p>;
};

const Container = () => {
  const actions = store.actions; // will not update

  return (
    <div>
      <button type="button" onClick={actions.decrease}>
        Decrease
      </button>
      <button type="button" onClick={actions.increase}>
        Increase
      </button>
      <OtherComp />
    </div>
  );
};

const App = () => (
  <Provider store={store}>
    <Container>
  <Provider>
)

classComponents

if you want to use store in class component follow this approach

class TestComponent extends Component {
  render() {
    const { increase, decrease, count } = this.props;
    return (
      <p onMouseEnter={increase} onMouseLeave={decrease}>
        {count}
      </p>
    );
  }
}

export default connect(store)(TestComponent);

useLocalStore

Use this instead of useReducer

import { useLocalStore } from "react-global-hook";

const App = () => {
  const [{counter}, actions] = useLocalStore(
    {
      counter: 0,
    },
    ({ setState, getState }) => ({
      increase() {
        const { counter } = getState()
        const newCounterValue = counter + 1;
        setState({ counter: newCounterValue });
      },
    }),
  );

  return (
    <div>
      <p>
        Count:
        {counter}
      </p>
      <button type="button" onClick={actions.increase}>
        Increase
      </button>
    </div>
  );
};

Store

import { createStore } from "react-global-hook";

const store = createStore(initialState, actions);

const { getState, actions, setState, useState, addListener } = store;

setState

Set partial state

setState({ counter: counter + 1 });

addListener

Add an event listener. Listener run when a state update

//Run when counter update
function logCounter() {
  console.log(store.getState().counter);
}
store.addListener(logCounter, ["counter"]);

actions

gives bound actions

store.actions.addToCounter(3);

Persist

For persist state add your function to listener

function persister(state) {
  asyncStorage.setItem("persist:key",JSON.stringify(state))
}
store.addListener(persister, ["token","username"]); // Whenever the token and username change, this function will call.

Performance

Avoid unreasonable repetition of setState for better performance. Because after each setState, every component that is connected with hook will be rendered again and every function added to listener will be run again. For Example

// Bad
actions = ({ setState, getState }) => ({
  clearSelected: () => {
    setState({ selected: "" });
    setState({ row: [] });
  },
});

// Good
actions = ({ setState, getState }) => ({
  clearSelected: () => {
    setState({
      selected: "",
      row: [],
    });
  },
});

---

Stories

• React use Hooks: How to use React Global Hook

Example

• Todo list - react-global-hook