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Graeme Geldenhuys <graemeg.lists@gmail.com> hat am 15. März 2012 um 10:07 geschrieben:
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>[...]
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> TfpgCanvas
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> |
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> +-- TfpgX11Canvas
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> |
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> +-- TfpgCanvasBase
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>
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>
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> TAgg2D
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> |
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> +-- TfpgCanvasBase
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>[...]
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> DefaultCanvasClass: TfpgCanvasBaseClass = nil;
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> [...]
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> function TfpgWindow.CreateCanvas: TfpgCanvasBase;
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> begin
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> writeln('>> TfpgWindow.CreateCanvas');
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> writeln(' DefaultCanvasClass = ' + DefaultCanvasClass.ClassName);
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> // result := TAgg2D.Create(self);
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> // result := TfpgCanvas.Create(self);
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> Result := DefaultCanvasClass.Create(self);
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> writeln('<< TfpgWindow.CreateCanvas');
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> end;
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> [...]
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> creating... TfpgX11Canvas
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> creating... TfpgCanvasBase
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>
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> NOTE the missing TfpgCanvas. Needless to say my program crashes instantly.
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>[...]
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> Can anybody see what I am doing wrong?
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<p style="margin: 0px;">Is the constructor virtual? </p>
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> I've tested with FPC 2.6.0, 2.6.1 and 2.7.1 under 64-bit Linux. All compilers give the same
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> results.
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<p style="margin: 0px;">>[...]</p>
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<p style="margin: 0px;">Mattias</p>
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