Sceneform SDK for Android was open sourced and archived (github.com/google-ar/sceneform-android-sdk) with version 1.16.0.
This site (developers.google.com/sceneform) serves as the documentation archive for the previous version, Sceneform SDK for Android 1.15.0.
Do not use version 1.17.0 of the Sceneform Maven artifacts.
The 1.17.1 Maven artifacts can be used. Other than the version, however, the 1.17.1 artifacts are identical to the 1.15.0 artifacts.

PinchGesture.OnGestureEventListener

Page Summary

PinchGesture.OnGestureEventListener defines callbacks for pinch gestures in AR scenes.
It inherits methods like onFinished and onUpdated from BaseGesture.OnGestureEventListener to handle gesture updates and completion.
These methods provide a PinchGesture object, giving access to gesture details during interactions.

public static interface PinchGesture.OnGestureEventListener

Interface definition for callbacks to be invoked by a PinchGesture.

From interface com.google.ar.sceneform.ux.BaseGesture.OnGestureEventListener

abstract void	onFinished(PinchGesture gesture)
abstract void	onUpdated(PinchGesture gesture)