CaptureController: setFocusBehavior() method

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The CaptureController interface's setFocusBehavior() method controls whether the captured tab or window will be focused when an associated MediaDevices.getDisplayMedia() Promise fulfills, or whether the focus will remain with the tab containing the capturing app.

You can set this behavior multiple times before the MediaDevices.getDisplayMedia() call, or once immediately after its Promise resolves. After that, the focus behavior is said to be finalized, and can't be changed.

Syntax

js
setFocusBehavior(focusBehavior)

Parameters

focusBehavior

An enumerated value that describes whether the user agent should transfer focus to the captured display surface, or keep the capturing app focused. Possible values are focus-captured-surface (transfer focus) and no-focus-change (keep focus on the capturing app).

Return value

None (undefined).

Exceptions

InvalidStateError DOMException

Thrown if:

  • The capture stream has been stopped.
  • The user chose to share a screen (displaySurface type monitor) rather than a browser tab or window — you can't focus a monitor. In this case the exception is thrown after the MediaDevices.getDisplayMedia() Promise resolves.
  • Enough time has elapsed after the MediaDevices.getDisplayMedia() Promise fulfills that the focus behavior has been finalized.

Examples

js
// Create a new CaptureController instance
const controller = new CaptureController();

// Prompt the user to share a tab, window, or screen.
const stream = await navigator.mediaDevices.getDisplayMedia({ controller });

// Query the displaySurface value of the captured video track
const [track] = stream.getVideoTracks();
const displaySurface = track.getSettings().displaySurface;

if (displaySurface == "browser") {
  // Focus the captured tab.
  controller.setFocusBehavior("focus-captured-surface");
} else if (displaySurface == "window") {
  // Do not move focus to the captured window.
  // Keep the capturing page focused.
  controller.setFocusBehavior("no-focus-change");
}

Specifications

Specification
Screen Capture
# dom-capturecontroller-setfocusbehavior

Browser compatibility

Report problems with this compatibility data on GitHub
desktopmobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
setFocusBehavior
Experimental

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support
No support
No support
Experimental. Expect behavior to change in the future.

See also