InstallEvent

The parameter passed into the oninstall handler, the InstallEvent interface represents an install action that is dispatched on the ServiceWorkerGlobalScope of a ServiceWorker . As a child of ExtendableEvent , it ensures that functional events such as FetchEvent are not dispatched during installation.

This interface inherits from the ExtendableEvent 接口。

构造函数

InstallEvent.InstallEvent()
创建新的 InstallEvent 对象。

特性

Inherits properties from its ancestor, Event .

InstallEvent.activeWorker 只读
返回 ServiceWorker that is currently controlling the page.

方法

Inherits methods from its parent, ExtendableEvent .

范例

This code snippet is from the service worker prefetch sample (见 prefetch running live .) The code calls ExtendableEvent.waitUntil() in ServiceWorkerGlobalScope.oninstall and delays treating the ServiceWorkerRegistration.installing worker as installed until the passed promise resolves successfully. The promise resolves when all resources have been fetched and cached, or when any exception occurs.

The code snippet also shows a best practice for versioning caches used by the service worker. Although this example has only one cache, you can use this approach for multiple caches. The code maps a shorthand identifier for a cache to a specific, versioned cache name.

注意 : Logging statements are visible in Google Chrome via the "Inspect" interface for the relevant service worker accessed via chrome://serviceworker-internals.

var CACHE_VERSION = 1;
var CURRENT_CACHES = {
  prefetch: 'prefetch-cache-v' + CACHE_VERSION
};
self.addEventListener('install', function(event) {
  var urlsToPrefetch = [
    './static/pre_fetched.txt',
    './static/pre_fetched.html',
    'https://www.chromium.org/_/rsrc/1302286216006/config/customLogo.gif'
  ];
console.log('Handling install event. Resources to pre-fetch:', urlsToPrefetch);
  event.waitUntil(
    caches.open(CURRENT_CACHES['prefetch']).then(function(cache) {
      return cache.addAll(urlsToPrefetch.map(function(urlToPrefetch) {
        return new Request(urlToPrefetch, {mode: 'no-cors'});
      })).then(function() {
        console.log('All resources have been fetched and cached.');
      });
    }).catch(function(error) {
      console.error('Pre-fetching failed:', error);
    })
  );
});
					

规范

规范 状态 Comment
服务工作者 工作草案 As of May 2015, the install event is an instance of ExtendableEvent rather than a child of it.

浏览器兼容性

更新 GitHub 上的兼容性数据
Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
InstallEvent
Chrome 40 Edge ≤79 Firefox 44
注意事项
44
注意事项
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE 不支持 No Opera 27 Safari 不支持 No WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 27 Safari iOS 不支持 No Samsung Internet Android 4.0
InstallEvent() 构造函数
Chrome 40 Edge ≤79 Firefox 44
注意事项
44
注意事项
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE 不支持 No Opera 27 Safari 不支持 No WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 27 Safari iOS 不支持 No Samsung Internet Android 4.0
activeWorker
Chrome 40 Edge ≤79 Firefox 44
注意事项
44
注意事项
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE 不支持 No Opera 27 Safari 不支持 No WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 27 Safari iOS 不支持 No Samsung Internet Android 4.0

图例

完整支持
完整支持
不支持
不支持
实验。期望将来行为有所改变。
实验。期望将来行为有所改变。
见实现注意事项。

另请参阅