Files
frontend-app-learning/src/generic/user-messages/hooks.js

36 lines
1.4 KiB
JavaScript

/* eslint-disable import/prefer-default-export */
import { useContext, useEffect } from 'react';
import UserMessagesContext from './UserMessagesContext';
export function useAlert(isVisible, {
code, text, topic, type, payload, dismissible,
}) {
const { add, remove } = useContext(UserMessagesContext);
// Please note:
// The deps list [isVisible, code, ... etc.] in this `useEffect` call prevents the
// effect from running if none of deps have changed. However, "changed" for objects is
// defined in terms of identity; thus, if you provide a payload that is *seemingly* equal
// to the previous one but *actually* a different object, then this effect will run.
// If you are particularly unlucky, this will cause an infinite re-render loop.
// This manifested itself in TNL-7400.
// We hope to address the underlying issue in TNL-7418.
// In the mean time, you may follow the pattern that `useAccessExpirationAlert`
// establishes: memoize the payload so that the exact same object is used if the
// payload has not changed. And don't put values based off of now() in your payload, as
// that breaks memoization.
useEffect(() => {
if (!isVisible) {
return undefined;
}
const cleanupId = add({
code, text, topic, type, payload, dismissible,
});
return () => {
remove(cleanupId);
};
}, [isVisible, code, text, topic, type, payload, dismissible]);
}