Monthly Archives: December 2009
Twitter & ESRI’s Silverlight API
Ever wonder what people are talking about at a particular location? This application, developed by the Application’s Prototype Lab, uses Twitter’s search API and ESRI’s Silverlight API to request and display geo-referenced tweets. The application is accessible from the following link. http://maps.esri.com/sldemos/twittermap/default.aspx
To use, first zoom into an area of interest (preferably an urban area). Click the Add button in the upper left hand corner of the application and then click once on the map. The ten most recent tweets within the search radius will be added to the map using the tweeter’s profile image. Mouse-over the profile images to read the tweets themselves. Next, try refining your search with a smaller (or larger) search radius and the inclusion of a search keyword like “#esri”.
The following technologies were used to develop this application:
- Microsoft Silverlight 3
http://silverlight.net/ - ESRI’s ArcGIS API for Silverlight version 1.1
http://resources.esri.com/arcgisserver/apis/silverlight/ - Microsoft Silverlight Toolkit (November 2009)
http://www.codeplex.com/Silverlight - Linq to Twitter
Comprehensive LINQ provider to Twitter’s API
http://linqtotwitter.codeplex.com/ - Orbifold’s Graphite for Silverlight
Simple framework for presenting spring-enabled node-edge diagrams.
http://www.orbifold.net/default/?page_id=1270
County Level Unemployment Maps
A new unemployment rate map has been making its way around the Internets lately. We here in the APL thought it would be a good time to post a link to a similar mapping app we put together earlier this year: Unemployment Rates – March 2009 to September 2009. This app originally showed October 2008 – April 2009 rates but was recently updated with new data from the BLS.
Our app basically shows the same data as the app linked above but includes a few extra goodies. There’s the ability zoom to a specific state or county by clicking a place name in the sidebar. Once zoomed in to a specific county, a chart for that county’s unemployment rate over time is displayed. Also, since this app was built with the ArcGIS API for JavaScript, all the usual navigation tools like shift + click and drag to zoom are available.
There are a few other examples of this type of app. The Bureau of Labor Statistics(BLS) hosts their own app to display this information: BLS Unemployment Rate Mapping Application. My personal favorite to visualize this data is probably one done by the New York Times back in March. The filters for metro areas, rural areas and manufacturing centers are a nice touch.
Contributed by Derek Swingley.
