How to zoom the camera lens by changing focal length?

William Wong

You can get the spec of focal lenth by calling KeyCameraHybridZoomSpec (get). the minFocalLength means the minimum optical zoom focal length, the maxOpticalFocalLength means the maximum optical zoom focal length, the maxFocalLength means the maximum digital zoom focal length, the focalLengthStep means the step length for each zoom, the unit for every parameter is mm.
You can call KeyCameraHybridZoomFocalLength (get/set/listen) to set the targeted focal length. Targeted focal length = current focal length + X * focalLengthStep.