You cannot add links directly, but you can emulate them in javascript. This forum has a number of threads on the topic (here's a recent one using GeoCharts instead of BarCharts, but the principal and mechanics are almost exactly the same:
https://groups.google.com/forum/?fromgroups=#!topic/google-visualization-api/hwQkXg-yJ2Q).
On Wednesday, September 5, 2012 8:53:37 AM UTC-4, George Lubaretsi wrote:
Hi,
Is it possible to add hyperlinks on data objects in the bar charts?
Thanks