This feature is well established and works across many devices and browser versions. It’s been available across browsers since April 2018.
* Some parts of this feature may have varying levels of support.
Note: This feature is only available in Service Workers.
The WindowClient interface of the ServiceWorker API represents the scope of a service worker client that is a document in a browsing 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.
WindowClient.focus()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.ancestorOrigins Read only Experimental
An array of strings that indicates the ancestor origins of the browsing context represented by this WindowClient in reverse order.
WindowClient.focused Read only
A boolean that indicates whether the current client has focus.
WindowClient.visibilityState Read only
Indicates the visibility of the current client. This value can be one of "hidden" or "visible".
self.addEventListener("notificationclick", (event) => {
console.log("On notification click: ", event.notification.tag);
event.notification.close();
// This looks to see if the current is already open and
// focuses if it is
event.waitUntil(
clients
.matchAll({
type: "window",
})
.then((clientList) => {
for (const client of clientList) {
if (client.url === "/" && "focus" in client) {
client.focus();
break;
}
}
if (clients.openWindow) return clients.openWindow("/");
}),
);
});
| Specification |
|---|
| Service Workers> # windowclient> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
WindowClient |
42 | 17 | 44 | 29 | 11.1 | 42 | 44 | 29 | 11.3 | 4.0 | 42 | No |
ancestorOrigins |
No | No | No | No | 16 | No | No | No | 16 | No | No | No |
focus |
42 | 17 | 44 | 29 | 11.1 | 42 | 44 | 29 | 11.3 | 4.0 | 42 | No |
focused |
42 | 17 | 44 | 29 | 11.1 | 42 | 44 | 29 | 11.3 | 4.0 | 42 | No |
navigate |
49 | 17 | 50 | 36 | 1611.1–16This method exists, but always throwsNotSupportedError. |
49 | 50 | 36 | 1611.3–16This method exists, but always throwsNotSupportedError. |
4.0 | 42 | No |
visibilityState |
42 | 17 | 44 | 29 | 11.1 | 42 | 44 | 29 | 11.3 | 4.0 | 42 | No |
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https://developer.mozilla.org/en-US/docs/Web/API/WindowClient