I have a problem when calling Qwidget::render() on a specific printer connected via a network to a PC running XP. I am quite new to using the Qprinter class so I apologise if I am missing something obvious. I get a repeatable crash when rendering to the printer in question. The only diffreence I can see between the working printers and the crashing one is the printer resolution. I seem to get the problem no matter what I render. The crash always seesm to occur at the render() call.

Here is attached example code:

Qt Code: 
  1. void MainWindow::menuPrintTest(){
  2.     double xscale;  double yscale;  double scale;
  3.     double printerWidth ;  double printerHeight ;
  4.     double widgetWidth;  double widgetHeight ;
  5.     QFont printFont("courier",  16);
  6.     printFont.setFixedPitch(TRUE);
  7.     QTextEdit *qteTestPrintRequest = new QTextEdit("",w);
  8.     qteTestPrintRequest ->setFont(printFont );
  9.     qteTestPrintRequest ->setFixedHeight(1750);
  10.     qteTestPrintRequest ->setFixedWidth(1050);
  11.     widgetWidth = qteTestPrintRequest ->width();
  12.     widgetHeight = qteTestPrintRequest ->height();
  13.  
  14.     QString qsConcat = "Test Printout For Checking XP Print Request Bug\n";
  15.     for (int i=0; i<30; i++){ qsConcat+= "Test Printout for Checking XP Print Request Bug\n" ; }
  16.     qteTestPrintRequest->append( qsConcat );
  17.  
  18.     QPrinter printer(QPrinter::HighResolution);
  19.     QString docName =   "Test Plot";
  20.     if ( !docName.isEmpty())  {
  21.         docName.replace (QRegExp (QString::fromLatin1 ("\n")), tr (" -- "));
  22.         printer.setDocName (docName);
  23.      }
  24.      QPrintDialog dialog(&printer);
  25.      if ( dialog.exec() )  {
  26.         {
  27.             {
  28.                 QPainter painter(&printer);
  29.                 printerWidth = printer.pageRect().width();
  30.                 printerHeight = printer.pageRect().height();
  31.                 xscale = printerWidth/(widgetWidth);
  32.                 yscale = printerHeight/(widgetHeight);
  33.                 scale = qMin(xscale, yscale);
  34.                 painter.scale(scale, scale);
  35.                 qteTestPrintRequest ->render(&painter);
  36.             }
  37.         }
  38.     }
  39. }
To copy to clipboard, switch view to plain text mode 





The qDebug() output for the scaling is as follows:

printerWidth = 4908.0
printerHeight = 6408.0
widgetWidth = 1050.0
widgetHeight = 1750.0
xscale = 4.674
yscale = 3.662
scale = 3.662

As a matter of interest the output on one of the working printers is

printerWidth = 4760.0
printerHeight = 6814.0
widgetWidth = 1050.0
widgetHeight = 1750.0
xscale = 4.533
yscale = 3.894
scale = 3.894