Using the DisplayFormat of the assigned TppField

rbuser

Hello,

datasets in my application have DisplayFormats assigned to several fields,
depending on the settings of the user.
In my RB templates I have DisplayFormats set to all appropriate
DBText-objects.

The problem is, that once the user changes the settings and the
DisplayFormats within the application become different, my RB templates
don't know anything about the changes and use "old" DisplayFormats, until
the user changes the template manualy.

This is not user friendly, so I'm looking for a way to automatically use the
DisplayFormats of the application in RB templates.
I've tried to set DisplayFormats of the pipeline fields, but this seems not
to have any effect on the templates.

Is there a way to accomplish that?

Best regards,
Mark

nicocizik

Hi Mark,

The DisplayFormat property of the TppField does not carry over to any
data aware components on a report. It is specifically used to define
the date format used when searching date fields (autosearch).

Once the template is loaded, you will need to go through each data aware
component and update its DisplayFormat property in order to reflect any
changes that have been made by your user.

rbuser

To cope with MultiCurrency in our app I have a RAP procedure called
FormatCurrencyFields that I get reports to call in the BeforePrint event
for the report:


procedure TFormatCurrencyFields.ExecuteFunction(aParams : TraParamList);
var lReport : TppCustomReport;
lCurrency : Integer;
begin
GetParamValue(0, lReport);
GetParamValue(1, lCurrency);


TnxReportsManager.ReportBuilderEngine.SetNumberFormatsForWholeReport(lReport,
lCurrency);
end;

class function TFormatCurrencyFields.GetSignature : String;
begin
result := 'procedure FormatCurrencyFields(aReport :
TppCustomReport; aCurrency: integer);';
end;


Then SetNumberFormatsForWholeReport() gets implemented thus:

procedure TrbReporting.SetNumberFormatsForWholeReport(aReport :
TppCustomReport; aCurrency : Integer);
var
lBandIndex : Integer;
lObjectIndex : Integer;
lObject : TppComponent;
lDataPipeline : TppDataPipeline;
lDataField : String;
lDataType : TppDataType;
begin
// for job based reports where currency is specific.
// This routine is called by our RAP pass-thru class
TFormatCurrencyFields
// allowing a report to auto fix up its display settings for number
fields with a single
// call to FormatCurrencyFields, e.g. FormatCurrencyFields(Report,
Invoice['JOBS.Currency']);

for lBandIndex := 0 to aReport.BandCount - 1 do
for lObjectIndex := 0 to aReport.Bands[lBandIndex].ObjectCount -
1 do
begin
lObject := aReport.Bands[lBandIndex].Objects[lObjectIndex];

if lObject is TppSubReport then
begin

SetNumberFormatsForWholeReport(TppSubReport(lObject).Report, aCurrency);
continue;
end;

if (lObject is TppDBText) or (lObject.InheritsFrom(TppDBText)) or
(lObject is TppVariable) then
// only set if nothing assigned (default)
// if TppCustomTextAccess(lObject).DisplayFormat = '' then
begin

lDataPipeline := TppDBText(lObject).DataPipeline;
lDataField := TppDBText(lObject).DataField;

if lObject is TppVariable then
lDataType := TppVariable(lObject).DataType else
lDataType := lDataPipeline.GetFieldDataType(lDataField);

case lDataType of

dtSingle,
dtDouble,
dtExtended : TppCustomTextAccess(lObject).DisplayFormat
:= CurrencyManager.CurrencySet[aCurrency].DecimalFomattingstring;

dtCurrency : TppCustomTextAccess(lObject).DisplayFormat
:= CurrencyManager.CurrencySet[aCurrency].CurrencyFomattingstring;

end;

end;

end;

end;

rbuser

Hi Nico,

it was my fear that the reply would be similar to what you wrote...
Don't you think that it would make sense to automatically use the
DisplayFormat of the TppField (as long assigned) for the data aware
component to which the field is assigned? This wouldn't do any harm to the
current functionality, would it? But it sure would be an improvement and
make it much easier to deal with such reports. Maybe an additional property
of the pipeline to control this behaviour? Something like
"ApplyDisplayFormatToDataAwareComponents"...

Regards,
Mark

rbuser

Hi Paul,

thank you for your reply and the example!
I will take a look into it.

Best regards,
Mark

rbuser

Hello,

is there a difference between

TppCustomTextAccess(lObject).DisplayFormat := ...
and
TppDBText(lObject).DisplayFormat := ...

or better to say what is the difference?

nicocizik

Thanks for the feedback. We will consider it for a later release.

rbuser

Ah, I forgot to mention that bit. TppCustomTextAccess is just a "cracker
class" that promotes Displayformat to PUBLIC as it is only PROTECTED in
the TppComponent that lObject is defined as:

TppCustomTextAccess = class(TppCustomText)
public
property Displayformat;
end;

Seemed more elegant than doing local casts (TppDBText(lObject) or
TppDBText(lObject) in the Displayformat :=...block) but you could do
that too.

rbuser

Ok, I see, thank you.

rbuser

Hello,

what do I have to pass as report-parameter form the ReportBeforePrint-event?
First I tried it with "Report". This seemed to work, then it didn't work as
myReport.BandCount appeared to be 0 for some reason, although I still see
everything in the designer. Once this happened, I tried to use
Report.MainReport as parameter, but since then I'm getting an access
vialotaion when attemtpting to check the BandCount, although the report is
not nil or something like that... Very weird.

Do you habve any ideas?

rbuser

Within RAP I am passing "Report" to my pass-thru procedure. Can't
imagine why BandCount would be 0, I'm afraid - its always > 0 here.

rbuser

It had worked here too first, then I've extended the parameters a bit etc.
and then suddenly it stopped to work or better to say seems to be random...
Sometimes I get an AV, sometimes a random integer value... I've put the
whole procedure into a try-except block and once the error occurs, the
report is showed in the preview as it was before - all the bands are there
etc.

Totaly clueless what is going on here.

rbuser

How is your Execute procedure coded (copy it here)?

rbuser

I was just about to copy&paste it here, when my eyes stopped at my local
variables to store the parameter values. I remembered something and wanted
to give it a try one last time and... it worked...

First I had this:

class function TraMySetDisplayFormat.GetSignature: String;
begin
Result := 'procedure mySetDisplayFormat(CurrentReport: TppCustomReport;
CurrencyKind: smallint);';
end;

var
lParamReport: TppCustomReport;
lParamCurrencyKind: smallint;
begin
GetParamValue(0, lParamReport);
GetParamValue(1, lParamCurrencyKind);
...

This didn't work at all. I couldn't even access my procedure because the
signature couldn't get compiled and the three was empty. Then I've changed
smallint to integer and it worked, but I changed it in GetSignature only,
i.e.

class function TraMySetDisplayFormat.GetSignature: String;
begin
Result := 'procedure mySetDisplayFormat(CurrentReport: TppCustomReport;
CurrencyKind: integer);';
end;

I'm sure it worked inbetween, but well, can't reproduce the cisrcumstances
now.
However, now that I was about to copy&paste my code here, I noticed that the
local variable lParamCurrencyKind was still declared as smallint. I've
changed it to integer too

var
lParamReport: TppCustomReport;
lParamCurrencyKind: integer;
begin
GetParamValue(0, lParamReport);
GetParamValue(1, lParamCurrencyKind);
...

and it works! A very strange behavior with not avialable bands / corrupt
Report-parameter as result, but well... It works now, so I can finally test
my procedure.

Thanks for your assistance!