Draw on QPrinter: color gets lost

[FelixB]

Hi,

I want to print something. That's not a big problem: I create a QPrinter and a QPainter to paint on the QPrinter. I can draw an image and some text. I also want to draw some lines. In the preview window (QPrintPreviewDialog), everything looks fine. But, when I print to PDF with an external PDF-Printer or to a real printer, the lines lose their color and appear in black. The Textcolor remains at it should be...

void MyClass::Print(bool preview)
  {
    QPrinter *printer = new QPrinter(QPrinter::HighResolution;
    printer->setPageMargins(20,20,20,20,QPrinter::DevicePixel);
    printer->setColorMode(QPrinter::Color);
    printer->setPageSize(QPrinter::A4);
    printer->setPrintRange(QPrinter::AllPages); 
 
    if(preview)
      {
        QPrintPreviewDialog ppd(printer);
        connect(&ppd, SIGNAL(paintRequested(QPrinter*)), this, SLOT(Print(QPrinter*)));
        ppd.exec();
      }
    else
      {
        QPrintDialog *printDialog = new QPrintDialog(printer, CMainFrame::GetMainFrame().GetMainWin());
        if (printDialog->exec()) 
          Print(printer);    
      } 
    delete printer;
  }

void MyClass::Print(bool preview)
  {
    QPrinter *printer = new QPrinter(QPrinter::HighResolution;
    printer->setPageMargins(20,20,20,20,QPrinter::DevicePixel);
    printer->setColorMode(QPrinter::Color);
    printer->setPageSize(QPrinter::A4);
    printer->setPrintRange(QPrinter::AllPages); 

    if(preview)
      {
        QPrintPreviewDialog ppd(printer);
        connect(&ppd, SIGNAL(paintRequested(QPrinter*)), this, SLOT(Print(QPrinter*)));
        ppd.exec();
      }
    else
      {
        QPrintDialog *printDialog = new QPrintDialog(printer, CMainFrame::GetMainFrame().GetMainWin());
        if (printDialog->exec()) 
          Print(printer);    
      } 
    delete printer;
  }

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void MyClass::Print(QPrinter* printer)
  {
//this is just a demonstration. My "real" code makes more sense ;)
 
    QPainter p(printer);
    QRectF border(QPoint(0,0), printer->pageRect().size() - QSize(1,1));
 
    p.setPen(Qt::red);
    p.drawRect(border);
 
    QDateTime time = QDateTime::currentDateTime();
    QString timestr = time.toString("dddd, MMMM d, yyyy hh:mm:ss");
    p.drawText(400, 400, timestr);
 
    p.drawLine(QLine(1000, 2000, 1800, 3500));
}

void MyClass::Print(QPrinter* printer)
  {
//this is just a demonstration. My "real" code makes more sense ;)

    QPainter p(printer);
    QRectF border(QPoint(0,0), printer->pageRect().size() - QSize(1,1));

    p.setPen(Qt::red);
    p.drawRect(border);

    QDateTime time = QDateTime::currentDateTime();
    QString timestr = time.toString("dddd, MMMM d, yyyy hh:mm:ss");
    p.drawText(400, 400, timestr);

    p.drawLine(QLine(1000, 2000, 1800, 3500));
}

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see the attached results. Preview: preview.png, Print:print.png

what can I do to print colored lines? I could draw everything onto a QPixmap first and
print this QPixmap. But I think this may be too much memory-consuming, especially when printing in HighResolution mode...

thanks!
Felix

[FelixB]

I solved it! I have to create a pen and set the width explicitly. weird...

QPen pen(Qt::red);
pen.setWidth(1);
p.setPen(pen);

QPen pen(Qt::red);
pen.setWidth(1);
p.setPen(pen);

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