The WindowClient interface of the ServiceWorker API represents the scope of a service worker client that is a document in a browser context, controlled by an active worker. The service worker client independently selects and uses a service worker for its own loading and sub-resources.


WindowClient inherits methods from its parent interface, Client.

Gives user input focus to the current client. 
Loads a specified URL into a controlled client page.


WindowClient inherits properties from its parent interface, Client.

WindowClient.focused 只读
A boolean that indicates whether the current client has focus.
WindowClient.visibilityState 只读
Indicates the visibility of the current client. This value can be one of hidden, visible, prerender, or unloaded.


self.addEventListener('notificationclick', function(event) {
  console.log('On notification click: ', event.notification.tag);

  // This looks to see if the current is already open and
  // focuses if it is
    type: "window"
  }).then(function(clientList) {
    for (var i = 0; i < clientList.length; i++) {
      var client = clientList[i];
      if (client.url == '/' && 'focus' in client)
        return client.focus();
    if (clients.openWindow)
      return clients.openWindow('/');


Specification Status Comment
Service Workers
Working Draft Initial definition

Browser compatibility

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!
Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 42.0 44.0 (44.0)[1] 未实现 ? 未实现
navigate() 49.0        
Feature Android Android Webview Firefox Mobile (Gecko) Firefox OS IE Mobile Opera Mobile Safari Mobile Chrome for Android
Basic support 未实现 未实现 44.0 (44.0) (Yes) 未实现 ? 未实现 42.0
navigate() 未实现 未实现           49.0

[1] Service workers (and Push) have been disabled in the Firefox 45 and 52 Extended Support Releases (ESR.)

See also