[Lazarus] Lazreport variables

[Santiago A.]

El 11/05/2020 a las 16:12, Graeme Geldenhuys via lazarus escribió:
> On 03/05/2020 5:03 pm, Santiago A. via lazarus wrote:
>> I want to write a report where even lines are written with no background
>> and odd lines with a light gray background.
> Have you considered using the newer FPReport (aka fcl-report) included
> with FPC? There is a report designer for Lazarus too. It is super simple
> to implement the alternating colors that you required. Take a look at
> the fcl-report/demos/ directory and look at the "rptexpressions.pas"
> unit. All you need to do is assign the alternating colors in the
> DoBeforePrint() event handler.
>
> eg:
>
> procedure TExpressionsDemo.DoBeforePrint(Sender: TFPReportElement);
> begin
>    With rpt.Variables.FindVariable('isEven') do
>      AsBoolean:=Not AsBoolean;
>    if rpt.Variables.FindVariable('isEven').AsBoolean then
>      Sender.Frame.BackgroundColor := clLtGray
>    else
>      Sender.Frame.BackgroundColor := clWhite;
> end;
>
>
>
> Regards,
>    Graeme
>

Yes, in fact I have solved it with a similar way using events in pascal.
Nevertheless, that is not the question. Do variables work in LazReport 
or not? if they do, how?
I have hidden a band and a few tweaks using the reports scripts, that 
means that I have divided the logic of the report in the scripts in lrf 
file and in events in the pascal source. If I can't trust that scripts 
work, I will move everything  to pascal and let the report just for 
basic graphic design with no script.

Using only pascal events is not the best solution, because I could, for 
example, change the design of alternate colors of the band to a line 
division without touching the pascal code and having to generate a new 
executable.

I still hope that I have misunderstood something about variables, or at 
least it is known bug.

-- 
Saludos

Santiago A.