React - create shared state across multiple components (using custom solution)

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import React, {createContext, useContext, useState, useMemo, useEffect} from 'react';

const createSharedState = (value) => {
    let _value = value;
    const _listeners = new Array();
    return {
        setValue: (value) => {
            for (const listener of _listeners) {
                listener(value);
            }
        },
        getValue: () => {
            return _value;
        },
        useValue: () => {
            const [counter, setCounter] = useState(0);
            useEffect(
                () => {
                    const listener = (value) => {
                        _value = value;
                        setCounter(counter => counter + 1);
                    };
                    _listeners.push(listener);
                    return () => {
                        var index = _listeners.indexOf(listener);
                        if (index !== -1) {
                            _listeners.splice(index, 1);
                        }
                    };
                },
                []
            )
            return _value;
        }
    };
};

const useSharedState = (value) => {
    return useMemo(
        () => createSharedState(value),
        [value]
    );
};



// Usage example:

const SharedState = createContext();

const Component1 = () => {
    const sharedState = useContext(SharedState);
    return (
        <div>
          <button onClick={() => sharedState.setValue('red')}>Set red</button>
          <button onClick={() => sharedState.setValue('green')}>Set green</button>
          <button onClick={() => sharedState.setValue('blue')}>Set blue</button>
        </div>
    );
};

const Component2 = () => {
    const sharedState = useContext(SharedState);
    const sharedValue = sharedState.useValue();
    return (
        <div>
          Shared value: {sharedValue}
        </div>
    );
};

const App = () => {
    const sharedState = useSharedState('default');  // replace 'default' with your default value
    return (
        <div className="app">
          <SharedState.Provider value={sharedState}>
            <Component1 />
            <Component2 />
            <Component2 />
            <Component2 />
          </SharedState.Provider>
        </div>
    );
};

export default App;