sub reports

[2001 JI Open Discussion]

By: Lenny Ridel - lennyridel

sub reports

2002-03-01 05:34

Hi Teodor

In future directions you mentioned that it is possible to create subreports with current version. Do you have an example?

Lenny

 

 

By: Teodor Danciu - teodord

RE: sub reports

2002-03-07 04:28

 

Hi,

 

This is not easy.

 

I have provided some explanations on a

previous thread on this forum, even in a

support request.

 

But the main target right now is to introduce

sub-reports support for good.

 

Thanks,

Teodor

 

 

 

By: Lenny Ridel - lennyridel

RE: sub reports

2002-03-07 12:59

Hi Teodor,

I'm trying to do something like this

 

Customer A

Product: Sugar Salt

Amount: 10 1

Customer B

Product: Sugar Milk Honey ...

Amount: 2 3 5

Product: AAA BBB CCC

Amount: 34 55 66

Custmer C

....

 

Can you advice? Will you support it with subreports

 

 

By: Teodor Danciu - teodord

RE: sub reports 2

2002-03-12 01:05

 

Hi, Lenny,

 

I have studied your problem a little and I think

it can not be solved by sub-reports.

Instead, implementing a special data source

for you report can solve it.

Sub-reports will act just like usual reports. They will generate report sections downwards

according to the data source they iterate through

and not horizontally.

 

I don't know if in the report structure you

presented the number of product name/price is

known at design time.

If this is the case, and lets say you want to

have at most 5 name/price pairs on each customer

products row, your problem can be solved with a

special designed data source.

 

This data source you have to create has to do

at least 2 things:

- it has to recognize the moment when the

customer changes in the data set;

- when the report engine calls its next() method,

it has to cache 5 ResultSet rows in one data

source row.

 

This means that you have to declare 5 product

name fields and 5 product price fields on you

report and you have to put them in the

corresponding text fields in the detail section

(we said that you have 5 name/price column pairs

on the detail section).

But is up to the data source to transform 5 rows

in the ResultSet object in one single data source

row with 5 products in it.

 

I can help you create such a data source,

but I think you got the idea by now.

 

This data source you will implement can inherit

directly from JRResultSetDataSource.

 

Good luck and keep in touch!

Teodor

 

 

 

By: Lenny Ridel - lennyridel

RE: sub reports 2

2002-03-12 09:40

Hi Teodor,

Thanks for advice. We hoped that subreport will solve the issue. Meanwhilem we choosed the following solution:

1. We defined customer field and N dummy fields.

2. We defined a group for customer.

3. For each customer we create a result of variable length.

4. Each time next is called we check whether more results exists, etc...

If you want we can share the code.

Lenny