TppReport.BeforePrint event: posiblle bug ?

rbuser

I have a big problem.

I use Pragnaan vcl to export report to other format. Then I need to give a
name for the file to be created. I read in the RB help that the filename for
device must be assigned in the BeforePrint event.

I create the code, try it with an embeded report and is ok. But, when I load
the report from a database, the link between the BeforePrint event and his
procedue is broken. Why ? Why the event is not stored (as txt) in the
template to the database ?

I solve it reasigning the event to the procedure after loading the report.
But, is it normal or s a bug ?



ADM

nicocizik

Hello,

The following article explains why you are loosing the reference to the
BeforePrint event. The easiest way around this issue is to use RAP and keep
all events local to the templates themselves.

--------------------------------------------
Article: Troubleshooting Lost Event Handlers
--------------------------------------------

Let's assume you have created a report in Delphi and assign an event
handlers to the OnPreviewFormCreate event of the report. The event is
generated by Delphi as:

procedure TForm1.ppReport1PreviewFormCreate(Sender: TObject);

You then save the report to an RTM file 'Report1.RTM.' The events are
stored as references only, and so the RTM contains:

object ppReport1: TppReport
.
.
OnPreviewFormCreate = ppReport1PreviewFormCreate
end

You then go on to work on a different report. Saving it with under then
name 'Report2.RTM'. Only this time, before you save the report you
change the report component name to: rptOrders. Delphi automatically
updates the event declaration for OnPreviewFormCreate event to:

procedure TForm1.rptOrdersPreviewFormCreate(Sender: TObject);


You then create two buttons on the form, one to load Report1 and
preview, the other to load Report2 and preview. When you run the app
and click Report1, you an error. This is because the Report1.RTM file
contains a reference to ppReport1PreviewFormCreate, a method which no
longer exists (at least with this name) in the form.

One answer is to load all your rtm files into the report component you
will be using for loading. Fix any errors, reassign any events that get
cleared. This will update your rtms to contain the proper event handler
names.

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