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I had 'Canvas does not allow drawing'

edited July 2001 in General
Hi,

I had a report that I was creating programmatically that had 2 subreports
with child reports in them and fields in each. When I ran it a I got to the
first field in the second child report it would report that the 'Canvas does
not allow drawing'. I tracked to the AutoSize:=true in the create of the
ppcustomlabel. When it does this assignment it goes and gets a handle for
the printer canvas and fails because it is returning a zero.

I had for my code to create the childreport:

ASubReport:=TppSubReport.Create(Self);
ASubReport.Band:=MainReport.DetailBand;

AChildReport:=TppChildReport.Ceate(Self);
AChildReport.Parent:=ASubReport;

ALabel:=TppLabel.Create(Self);
etc.

I found a tip that created the child report differently. It had:


ASubReport:=TppSubReport.Create(Self);
ASubReport.Band:=MainReport.DetailBand;

ASubReport:CreateReport(MainReport); //<<
AChildReport:=TppChildReport(ASubReport.Report); //<<

ALabel:=TppLabel.Create(Self);
etc.

This solved the problem. I'm not sure why. If you see this problem, try
looking for this.

Thanks,

Joseph Gordon

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