Overview

This repository includes a demonstration of an interactive dropdown list that allows the user to select a U.S. county for use as a filter in an interactive user interface.

The dropdown also doubles as a search interface; when the user types a search term into the text field, the options in the dropdown list are filtered to display only those items that match the user's input.

Region, state, and county relationships follow U.S. Census Bureau designations; the data used to generate the list of options in this dropdown are taken from https://gist.githubusercontent.com/bleonard33/be9e060afc8be3925ab20188b160e483/raw/96f860da16984aacb7db297daa48cf12f50420f7/hierarchy.json.

How to run this demonstration

This demonstration uses d3-fetch and d3-selection for data loading and DOM manipulation tasks. Webpack is used to coordinate package dependencies and run a server. Installing these dependencies is required to run this demonstration. After cloning this repository:

• Run npm install to install dependencies
• Run npm start and navigate to http://localhost:8000/ to see the application