This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.
The focus() method of the WindowClient interface gives user input focus to the current client and returns a Promise that resolves to the existing WindowClient.
Syntax
Client.focus().then(function(WindowClient) {
// do something with your WindowClient once it has been focused
});
Parameters
None.
Returns
A Promise that resolves to the existing WindowClient.
Example
self.addEventListener('notificationclick', function(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(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('/');
}));
});
Specifications
| Specification | Status | Comment |
|---|---|---|
| Service Workers The definition of 'focus()' in that specification. |
Working Draft | Initial definition. |
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
|---|---|---|---|---|---|
| Basic support | 42.0 | 44.0 (44.0)[1] | No support | ? | No support |
| Feature | Android | Firefox Mobile (Gecko) | Firefox OS | IE Mobile | Opera Mobile | Safari Mobile | Chrome for Android |
|---|---|---|---|---|---|---|---|
| Basic support | ? | 44.0 (44.0) | (Yes) | No support | ? | No support | 42.0 |
[1] Service workers (and Push) have been disabled in the Firefox 45 and 52 Extended Support Releases (ESR.)