Earlier this month Web AppBuilder was released with ArcGIS Online and the Portal for ArcGIS extension to ArcGIS for Server, allowing users to build powerful GIS apps that run on any device! Now with the release of the Developer Edition, … Continue reading
Mapping data values by varying the color has been the most popular way to visualize geospatial data. Academically it is called choropleth by cartographers. If you do an image search for “US population map” online, 90% of the results would be choropleth maps. In this post, we will look at this well-known mapping technique, and learn how you can create a map with our contemporary, easy-to-use API.
In this post, you will learn how to:
- Use pop-up to provide additional information
- Add legend
- Trigger actions when a graphic is clicked
In the first post of this series, I mentioned a good way to determine which way to visualize your data is to ask questions about the purpose of the map. In addition to “where things are,” which we already examined in that post, you may also want answer questions like:
- What chain does each restaurant belong to in my city?
- What is the most predominant crop of each county in the US?
- What level of crime risk does each census tract have?
Unique value renderer is good for answering your what questions.