Use RAP in Delphi (was: Looking for a suitable OO approach)

rbuser

Because I have to do all sorting before printing, I (or the end users) then
need the possibility to define
calculated fields for special kind of groupings or so.
Imagine some kind of predefined dataset. And now it comes into the mind of
some end user that he wants this
data to be grouped by something I never would have thought of.
Because he cannot do it in the report designer I have to offer this feature
in my app (some kind of "data-designer").
It would be nice if the end user could use the same RAP for the calculated
fields he uses inside the report designer.

Is this possible?

--Heiko

nicocizik

Hi Heiko,

Your end users can use the Data Tab of the Report Designer to sort, define
groups, and create calculated fields if they want. This is specifically
what DADE is for. You can enable DADE for the end user by adding the daIDE
file to your uses clause. I would suggest taking a look at the
ReportBuilder Developer's Guide for some examples and information on how
DADE can be useful in your application.

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rbuser

> Your end users can use the Data Tab of the Report Designer to sort, define
daIDE

When you say "calculated fields" are you talking about SQL aggregate
functions or
delphi-like calculated fields? I need the latter.
In DADE assistant I could only find SQL aggregations!?

And DADE seems to allow the end user to do anything he wants.
But I only would like give the end user the possibility to say:

OK, let's start with Invoice (starting point might be forced by
application).
What else do I need? I need the InvoiceItems, and Products and so on.
And because I have the complete metadata defined somewhere, the application
could offer all possible associations to related datasets. But not more!
I I would also like to predefine some calculated fields for each dataset.
If the end user has "collected" all datasets he might define the sorting of
each dataset.
And if the predefined columns do not have enough sorting information, the
end user
can define calculated fields (preferably via RAP).

--Heiko

nicocizik

Hi Heiko,

I'm confused when you would like to give your users the ability to do all of
these things. RAP code only executes when the report generates (i.e. during
preview or print). Do you want to let your users modify the sort order and
create calc components when designing the report? If so, I suppose you
could create a custom dialog that they can use to modify the current dataset
and automatically add calculation components to the report for them.

One of the main limitations of RAP is that none of the events fire early
enough to edit the datasets properly. It is on our todo list to improve
this for a later release.

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