service-worker.js

importScripts('https://storage.googleapis.com/workbox-cdn/releases/6.0.2/workbox-sw.js');

workbox.routing.registerRoute(
    ({request}) => request.destination === 'image',
    new workbox.strategies.NetworkFirst()
);

const cacheName = 'SzGames-1';
// List the files to precache
const precacheResources = [
 '/Offline.html'
];

// When the service worker is installing, open the cache and add the precache resources to it
self.addEventListener('install', (event) => {
  console.log('Service worker install event!');
  event.waitUntil(caches.open(cacheName).then((cache) => cache.addAll(precacheResources)));

});

const cacheNamesToDelete = ['Sz-Games', 'SzGames'];

self.addEventListener('activate', (event) => {
  console.log('Service worker activate event!');
  event.waitUntil(
    caches.keys().then(cacheNames => {
      return Promise.all(
        cacheNames.filter(cacheName => {
          // Delete the specific caches
          return cacheNamesToDelete.includes(cacheName);
        }).map(cacheName => {
          return caches.delete(cacheName);
        })
      );
    })
  );
});


self.addEventListener('fetch', event => {
    event.respondWith(
      caches.match(event.request).then(response => {
        if (response) {
          return response;
        }
        return fetch(event.request);
      })
    );
  });