When rendering grouped reports you may use more than one grouping to achieve the desired output, known as 'nesting'. For example, you might group Customers by location and then sub group them alphabetically. To achieve this style of report you should put the required number of GroupHeader bands before the DataBand and ideally the same number of GroupFooter bands immediately after it:
Although it is possible to leave out unwanted GroupFooters it is recommended that you always place equal numbers of GroupHeader and GroupFooter bands on a report to avoid unexpected results. If the number of GroupFooter bands is greater than the number of GroupHeader bands then the outer ones will be used and the inner bands ignored. If the number of GroupFooter bands is less than the number of GroupHeader bands, then the GroupHeader bands placed closer to the Data band will be output without footers.
Important:
It is recommended to have
equal number of GroupHeader
and GroupFooter
bands in a
report.
In each GroupHeader band you must specify the grouping criteria. When rendering the report the GroupHeader bands are processed in the in which they appear on a page working from the top down i.e. the topmost band is processed first, then the one that is placed directly underneath it and so on. When placing GroupFooter bands on a report page it is important remember that the last GroupFooter band is always associated with the first GroupHeader band.