Products Google for Education Blockly Reference FieldDropdown.OptionsObserver public static interface FieldDropdown.OptionsObserver Interface to listen for changes that occur to an FieldDropdown.Options list. Public Method Summary abstract void onOptionsUpdated(FieldDropdown.Options options) Public Methods public abstract void onOptionsUpdated (FieldDropdown.Options options) Parameters options 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 January 25, 2019.