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web api instance method

CaptureController: resetZoomLevel() method

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The CaptureController interface’s resetZoomLevel() method resets the captured display surface’s zoom to its initial level, which is 100.

The resetZoomLevel() method must be invoked via transient activation. In addition, the user is asked for permission to share tabs when screen capture is first attempted; if the user denies permission the zoom level cannot be changed even with transient activation.

Syntax

resetZoomLevel()

Parameters

None.

Return value

A Promise that fulfills with undefined.

Exceptions

  • InvalidStateError DOMException
    • : An attempt is made to invoke resetZoomLevel() without transient activation.
  • NotAllowedError DOMException
    • : Thrown when:

Examples

Basic resetZoomLevel() usage

The following snippet adds an event listener to a button so that when it is clicked, the resetZoom() function is called. This in turn calls the resetZoomLevel() method, resetting the captured surface’s zoom level to 100.

// Create controller and start capture
const controller = new CaptureController();
videoElem.srcObject = await navigator.mediaDevices.getDisplayMedia({
  controller,
});

// ...

resetBtn.addEventListener("click", resetZoom);

async function resetZoom() {
  await controller.resetZoomLevel();
}

See Using the Captured Surface Control API for a full working example.

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also