Products Google APIs for Android Reference ListenerToken public interface ListenerToken Token for identifying registered listeners. This token will be returned by certain calls to register event listeners. Use this token when unregistering the listener. Except as otherwise noted, the content of this page is licensed under the Creative Commons Attribution 3.0 License, and code samples are licensed under the Apache 2.0 License. For details, see our Site Policies. Java is a registered trademark of Oracle and/or its affiliates. Last updated November 6, 2017.