2/18/2017 - updated download link
The Acme Widget in the Hamilton County WAB Viewer is a "headless" widget that adds lots of functionality and modifies the behavior and/or appearance of a lot of Esri Widgets (without modifying their code). The Anvil series of widgets are simplified versions of the Acme Widget, demonstrating just one or two nuggets of functionality.
This widget is a sample of how to create a "headless" widget for the Wed AppBuilder (WAB). By "headless," I
mean it is invisible and it is loaded at startup. This sample adds map tips on feature layers.
There is no live sample for this widget, as it is invisible.