TfrxPictureView don't accept different PNG's anymore

Hans Brenkman

Hi,

In FastReport v4 I used to fill TfrxPictureView with a TClientDataset-field from a database which contains a PNG-picture. In FastReport v5.3 and v5.3.14 this don't work anymore.

In frxReport.OnManualBuild :

Pict := MyReport.FindObject('Picture1') as TfrxPictureView;
if (Pict <> nil) then
begin
  MS := TMemoryStream.Create;
  try
    cdsLookupConfigLOGO_RAPPORT.SaveToStream(MS);

    Pict.LoadPictureFromStream(MS);
  finally
    MS.Free;
  end;
end;

OR in frxReport.OnBeforePrint :

if Sender.Name = 'Picture1' then
begin
  MS := TMemoryStream.Create;
  try
    cdsLookupConfigLOGO_RAPPORT.SaveToStream(MS);

    TfrxPictureView(Sender).LoadPictureFromStream(MS);
  finally
    MS.Free;
  end;
end;

You can add a PNG in the TfxrPictureView.Picture property, but if you want to use different PNG-pictures for each report that's no option, so this has te be done the way I did it before or to define a frxDBDataSet to the property TfrxPictureView.DataSet and the field to TfrxPictureView.DataField.

All possibilities mentioned above work fine in v4 but in not v5 with PNG's, just (a.f.a.i.k.) JPG's.

How can I solve this problem ?

[Edit]

I think it has something to do with recognising with the defined const in frxClass.pas of OriginalPNGHeader

const
  OriginalPngHeader: array[0..7] of AnsiChar = (#137, #80, #78, #71, #13, #10, #26, #10);

When compiling I get a warning: "frxClass(7517: W1061 Narrowing given WideChar constant (#$0089) to AnsiChar lost information" so I guess the header of the PNG-picture isn't recognized as a PNG because of #137 ....
[/Edit]

Hans Brenkman

The problem is solved with changing the const OriginalPngHeader (deleted #137 and made the array 1 smaller)

const
//OriginalPngHeader: array[0..7] of AnsiChar = (#137, #80, #78, #71, #13, #10, #26, #10);
  OriginalPngHeader: array[0..6] of AnsiChar =       (#80, #78, #71, #13, #10, #26, #10);

I left the var PNGHeader its original size.

  PNGHeader: array[0..7] of AnsiChar;

And in TfrxPictureView.LoadPictureFromStream

    {$IFDEF PNG}
    if not bOK then
    begin
      if (s.Size-pos) >= SizeOf(PNGHeader) then
      begin
        // try png header
        s.ReadBuffer(PNGHeader, SizeOf(PNGHeader));
        s.Position := pos;
//      if PNGHeader = OriginalPngHeader then
        // replaced compare above with compare down here
        if (PNGHeader[0] = AnsiChar($0089)) and (copy(PNGHeader, 2, 8) = OriginalPngHeader) then
        begin
          NewGraphic := TPngObject.Create;
          bOK := True;
        end;
      end;
    end;
    {$ENDIF}

Somebody knows a better solution ?