react-native-mmkv/lib/hooks/useMMKVKeys.js

⚡️ The fastest key/value storage for React Native.

import { useState } from 'react';
import { getDefaultMMKVInstance } from '../createMMKV/getDefaultMMKVInstance';
import { useMMKVListener } from './useMMKVListener';
/**
 * Get a list of all keys that exist in the given MMKV {@linkcode instance}.
 * The keys update when new keys are added or removed.
 * @param instance The instance to listen to changes to (or the default instance)
 *
 * @example
 * ```ts
 * useMMKVKeys(instance)
 * ```
 */
export function useMMKVKeys(instance) {
    const mmkv = instance ?? getDefaultMMKVInstance();
    const [allKeys, setKeys] = useState(() => mmkv.getAllKeys());
    useMMKVListener((key) => {
        // a key changed
        setKeys((keys) => {
            const currentlyHasKey = keys.includes(key);
            const hasKey = mmkv.contains(key);
            if (hasKey !== currentlyHasKey) {
                // Re-fetch the keys from native
                return mmkv.getAllKeys();
            }
            else {
                // We are up-to-date.
                return keys;
            }
        });
    }, mmkv);
    return allKeys;
}