gatsby-plugin-theme-switcher/use-local-storage.js

React theme switcher with hooks and preventing the initial flash

"use strict";

exports.__esModule = true;
exports.default = useLocalStorage;

var _react = require("react");

/* eslint-disable no-unused-expressions */

/* eslint-disable no-undef */
function useLocalStorage(key, initialValue) {
  const [storedValue, setStoredValue] = (0, _react.useState)(() => {
    try {
      const item = typeof window !== "undefined" ? window.localStorage.getItem(key) : undefined;
      return item ? JSON.parse(item) : initialValue;
    } catch (error) {
      return initialValue;
    }
  });

  const setValue = value => {
    try {
      const valueToStore = value instanceof Function ? value(storedValue) : value;
      setStoredValue(valueToStore);
      typeof window !== "undefined" && window.localStorage.setItem(key, JSON.stringify(valueToStore));
    } catch (error) {// console.log(error);
    }
  };

  return [storedValue, setValue];
}