Cross-Tab

rbuser

I'm new to RB.
I succeeded in generating a CrossTab in code. I add rows and values
depending on the user needs. Now I need something tricky. Depending on the
Grand Total of a row, I need to decide to show or not to show this row.
First, is it possible ? If so, how can I do this (wich event is fired at
the right moment and geves me access to the grand total before printing the
row)?

Thanks
--
Frederic Gelinas
www.si.qc.ca

digitalmetaphors

The easiest way to hide a row, would be to create a calculated field on your
dataset, and limit the dataset based on that calculation - the record would
never get generated in the crosstab. This is the preferred approach.

If this isn't feasible, then you'll need to get inside the crosstab
renderer. Create a descendent cross tab renderer that is able to hide rows.
You may be able to do this by modifying the generated crosstab matrix of
values during generation. Set the values to some 'hide' flag value you want.
Then when the renderer looks at the matrix values to generate the draw
commands for the output, it can skip the matrix values that have this
special 'hide' flag.

Another option may be to just use the currently generated crosstab. Loop
through all of the draw commands, looking for the grand totals that you want
to hide. The fun part is going to be looping back through the draw commands,
which are on the same row, and removing those. Now, all of the draw commands
below the crosstab need to be shifted up one row height. You'll also have
to modify the vertical gridlines draw commands. Use the Report.OnEndPage
event to modify the draw commands on the page object, just before the page
gets sent to the output device.



Cheers,

Jim Bennett
Digital Metaphors

rbuser

Well. Not being really used to RB, I think I will try to limit my query
before it is sent to the report. I won't be easy, but it will require less
coding.

Thanks a lot for you help.

By the way, I really don't regret switching to RB. It is very easy to use
and enough flexible to accomodate many situations. It worths the money!
--
Frederic Gelinas
www.si.qc.ca

digitalmetaphors

Here's how you can find a draw command on a page and remove it based on its
text value. Here it searches for the CustNo = 1351 draw command.for a
simple Orders dbDemos table crosstab.


uses
ppDrwCmd, ppDevice;

procedure TForm1.ppReport1EndPage(Sender: TObject);
var
lPage: TppPage;
liIndex: Integer;
lDrawCommand: TppDrawCommand;
liValue: Integer;
lsText: String;
liDrawCommandCount: Integer;
begin

lPage := ppReport1.Engine.Page;

liDrawCommandCount := lPage.DrawCOmmandCount;
liIndex := 0;

while (liIndex < (liDrawCommandCount - 1)) do
begin

lDrawCommand := TppDrawCommand(lPage.DrawCommands[liIndex]);

if lDrawCommand is TppDrawText then
begin

lsText := TppDrawText(lDrawCommand).Text;

liValue := StrToIntDef(lsText, -1);

if (liValue <> -1) then
begin

if (liValue = 1351) then
begin
lPage.RemoveDrawCommand(lDrawCommand);

Dec(liDrawCommandCount);
end;

end;

end;

Inc(liIndex);

end;

end;

procedure TForm1.Button1Click(Sender: TObject);
begin
ppReport1.Print;
end;


Cheers,

Jim Bennett
Digital Metaphors