Grouping using a variable

[sa.asmus]

Hi all,

I have problems displaying my report in the way I need it to be:

I have a .csv file as data source which contains multiple types of data sets with various fields dependent on the value in the first column. For example:

100;<header_data>
130;<sub_header_data>
200;<pos1_data>
200;<pos2_data>

I want to format the visualisation of each type of data set separately so my attempt was to create a group header for the 100-set and another group
header for the 130s-set and display the pos data from the 200 set in the details section.

To achieve this I created a variable called "CountSet100" which consists of the following expression:

$F{data_set}.equals("100") ? $V{CountSet100} + 1 : $V{CountSet100}[/code]

... with "data_set" being my first column of each line. So the variable increments each time a 100-set is read. For my understanding of groups a group should
be created each time the group expression changes, in this case (I set $V{CountSet100} as group expression) when CountSet100 increments. But it doesn't.

Actually a group header is created each time a csv line is read allthough the value of $V{CountSet100} changes as expected: Only when a 100-set occurs.

Can anybody help me with this or explain what am I doing wrong here?

Thanks in advance!