Adding Drill-down Capabilities
    
      One of the most attractive features of Google Maps is their
      drill-down capabilities: clicking a Map Marker in a map causes a
 pop-up info panel to open, which can contain detail information. The same
 is true for Map Polygons - they can also be clicked in order to drill into
 the data. Continuing with the previous example, found in Creating a Map with Polygons, here's how this capability
 is added:

- 
        In the report definition, start by selecting the Map Polygons element.
 Beneath it add an Action.Map Marker Info element, and then
 beneath it, a Map Marker Info element, as shown above. Neither
 needs any configuration beyond being given an ID. 

 
- 
        Beneath the Map Marker Info element, add a Division element and
 beneath it add several Label and New Line elements, as
 shown above. The Division allows a uniform style to be applied to the
 Labels, and the Labels display detail data from the datalayer, which is
 still in scope. Note the use of an @Data token to display the school
 district name.

 
- 
        Next select the Map Marker Info element again and beneath it add
        SubReport and Target.Report elements, as shown above. This
 will allow you to add a chart or table, defined in a separate
 definition, to the pop-up info panel. 
 The
        Frame Border and Scrolling attributes are set to
        False so that the chart or table will embed smoothly into the
 pop-up panel.
 
- 
        Finally, a Link Parameters element can be added beneath the
 SubReport element, as shown above, to pass identifying information to
 the detail report.
 

The resulting pop-up information panel displayed when a polygon is clicked is shown above.