The url-formula chart property allows you to layer an image map over your report
HTML output. In essence, you are associating a link to the series key, (or chart key in pie charts), and category key. You can enter a formula
manually or build the formula by clicking (Field Selector) and making the
appropriate selections.
Formula:
www.google.com/#hl=en&source=hp&q=" & ["chart::series-key"] & " " & ["chart::category-key"]
Report Output:
When report consumers hover over a bar in chart, the relevant web page appears.
Formula:
="http://www.google.com/images?hl=en&source=imghp&biw=1163&bih=628&q=" & ["chart::key"]
Report Output:
When consumers of the report hover over a slice in the pie chart, the relevant label associated with the chart appears.
For more information, see Pentaho Reporting and BI Server 3.8 Preview and Demo.