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| app.js
if ('serviceWorker' in navigator) {
window.addEventListener('load', () => {
navigator.serviceWorker.register('/sw.js')
.then(registration => {
console.log('Service Worker registered with scope:', registration.scope);
})
.catch(error => {
console.error('Service Worker registration failed:', error);
});
});
}
index.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>PWA Demo</title>
<link rel="stylesheet" href="style.css">
<link rel="manifest" href="manifest.json">
</head>
<body>
<header>
<h1>PWA Demo</h1>
</header>
<main style="background: red;">
<p>This is a simple PWA demo.</p>
</main>
<script src="app.js"></script>
</body>
</html>
manifest.json
{
"name": "PWA Demo",
"short_name": "PWA Demo",
"start_url": "/",
"display": "standalone",
"background_color": "#f0f0f0",
"theme_color": "#4CAF50",
"icons": [
{
"src": "icon-192x192.png",
"sizes": "192x192",
"type": "image/png"
},
{
"src": "icon-512x512.png",
"sizes": "512x512",
"type": "image/png"
}
]
}
style.css
body {
font-family: Arial, sans-serif;
margin: 0;
padding: 0;
display: flex;
flex-direction: column;
align-items: center;
justify-content: center;
height: 100vh;
background-color: #f0f0f0;
}
header {
background-color: #4CAF50;
color: white;
width: 100%;
text-align: center;
padding: 10px 0;
}
main {
text-align: center;
}
img {
margin-top: 20px;
}
sw.js
const CACHE_NAME = 'pwa-demo-cache-v1';
const urlsToCache = [
'/',
'/index.html',
'/style.css',
'/app.js'
];
self.addEventListener('install', async event => {
const cache = await caches.open(CACHE_NAME);
await cache.addAll(urlsToCache);
await self.skipWaiting();
});
self.addEventListener('activate', async event => {
const keys = await caches.keys();
keys.forEach(key => {
if (key !== CACHE_NAME) {
caches.delete(key);
}
});
await self.clients.claim();
});
self.addEventListener('fetch', event => {
// 1. 只缓存同源的内容
const req = event.request;
const url = new URL(req.url);
if (url.origin !== location.origin) {
return;
}
// 2. 接口走网络优先策略 静态资源走缓存优先策略
if (req.url.includes('/api/')) {
event.respondWith(
networkFirst(event.request)
);
} else {
event.respondWith(
cacheFirst(event.request)
);
}
});
// networkFirst 一般适用于动态资源
async function networkFirst(request) {
const cache = await caches.open(CACHE_NAME);
try {
const response = await fetch(request);
//保证缓存最新的数据
cache.put(request, response.clone());
return response;
} catch (error) {
const cachedResponse = await cache.match(request);
return cachedResponse;
}
}
// catchFirst 一般适用于静态资源
async function cacheFirst(request) {
const cache = await caches.open(CACHE_NAME);
const cachedResponse = await cache.match(request);
if (cachedResponse) {
return cachedResponse;
}
const response = await fetch(request);
cache.put(request, response.clone());
return response;
}
|
