WindowClient: focus() method

The focus() method of the {{domxref("WindowClient")}} interface gives user input focus to the current client and returns a {{jsxref("Promise")}} that resolves to the existing {{domxref("WindowClient")}}.

Syntax

js-nolint

focus()

Parameters

None.

Return value

A {{jsxref("Promise")}} that resolves to the existing {{domxref("WindowClient")}}.

Exceptions

InvalidAccessError {{domxref("DOMException")}}
- : The promise is rejected with this exception if none of the windows in the app's origin have transient activation.

Security requirements

At least one window in the app's origin must have transient activation.

Examples

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) return client.focus();
        }
        if (clients.openWindow) return clients.openWindow("/");
      }),
  );
});