Create a PDF from Qt Creator

[TheCipo76]

@TheCipo76

when i launch pdf print in Application Output i saw this message:

QPainter::begin(): Returned false
QPainter::setPen: Painter not active
QPainter::end: Painter not active, aborted

Any suggestion to fix it??

[mrjj]

@TheCipo76
Hi
My guess would be that printer object goes out of scope ?

[TheCipo76]

@mrjj i've tried with this code:

qreal top=20, left=15, right=15, bottom=20;
    QPrinter printer(QPrinter::PrinterResolution);
    QPrintDialog dialog(&printer, this);
    if(dialog.exec() == QDialog::Accepted){
        QPrinterInfo pinfo(printer);
        qDebug() << "Printer valid: " << printer.isValid();
        qDebug() << "Printer Name: " << printer.printerName();
        qDebug() << "Printer program: " << printer.printProgram();
        qDebug() << "Is printer null: " << pinfo.isNull();
        qDebug() << "Printer State: " << pinfo.state();
        qDebug() << "Is printer default: " << pinfo.isDefault();
        qDebug() << "Is printer remote: " << pinfo.isRemote();
    }
    printer.setPaperSize(QPrinter::A4);
    printer.setPageMargins(left, top, right, bottom, QPrinter::Millimeter);
    printer.setOutputFormat(QPrinter::PdfFormat);
    printer.setOutputFileName("PrimoPDF.pdf");

    QPainter painter;
    if (! painter.begin(&printer)) { // failed to open file
        qWarning("failed to open file, is it writable?");
        return;
    }
    painter.drawText(10, 10, "Primo PDF Creato!");
    painter.drawText(10, 30, "Test 1");
    if (! printer.newPage()) {
        qWarning("failed in flushing page to disk, disk full?");
        return;
    }
    painter.drawText(10, 10, "Test 2");
    painter.end();

and this is the result:

Printer valid: true
Printer Name: "Samsung_CLP_620_Series__SEC001599489B1A_"
Printer program: ""
Is printer null: false
Printer State: 0
Is printer default: true
Is printer remote: false

Printer seem to be OK

now the previous message about QPainter were not showed..

[mrjj]

@TheCipo76
That looks very ok.
But no PDF (PrimoPDF.pdf) is produced ?

Have a look at this code. it prints screen shots.
Looks very similar to yours.

void printv2(QPixmap& pix) {

  QPrinter printer(QPrinter::HighResolution);
  printer.setOrientation(QPrinter::Landscape);
  printer.setOutputFormat(QPrinter::PdfFormat);
  printer.setPaperSize(QPrinter::A4);
  printer.setOutputFileName("e:/test.pdf");

  QPainter painter;
  painter.begin(&printer);

  double xscale = printer.pageRect().width() / double(pix.width());
  double yscale = printer.pageRect().height() / double(pix.height());
  double scale = qMin(xscale, yscale);
  painter.translate(printer.paperRect().x() + printer.pageRect().width() / 2,
                    printer.paperRect().y() + printer.pageRect().height() / 2);
  painter.scale(scale, scale);
  painter.translate(-pix.width() / 2, -pix.height() / 2);
  painter.drawPixmap(0, 0, pix);
  painter.end();

}


void MainWindow::on_pushButton_released() {

  QPixmap pix = QPixmap::grabWindow(QApplication::desktop()->winId());
  printv2(pix);

}

[TheCipo76]

@mrjj No, "PrimoPDF.pdf" wasn't created..

the code you have posted is very similar..

[mrjj]

@TheCipo76
Yep and i get a e:/test.pdf so not really sure why you dont get any.
does it try to print to real printer ?

Can you try

void printv3() {

  QPrinter printer(QPrinter::HighResolution);
  printer.setOrientation(QPrinter::Landscape);
  printer.setOutputFormat(QPrinter::PdfFormat);
  printer.setPaperSize(QPrinter::A4);
  printer.setOutputFileName("test.pdf");

  QPainter painter;
  painter.begin(&printer);

  painter.drawText( 200,200, "HELLO" );
  painter.end();

}

That give me a test.pdf in the build folder

and expected result

[TheCipo76]

@mrjj i've tried with no luck

test.pdf was not created..

[mrjj]

@TheCipo76
Really odd. I cant guess sorry. Sample works here.
You use the code directly as is ?

[TheCipo76]

@mrjj Yes, copied and pasted

QPrinter printer(QPrinter::HighResolution);
      printer.setOrientation(QPrinter::Landscape);
      printer.setOutputFormat(QPrinter::PdfFormat);
      printer.setPaperSize(QPrinter::A4);
      printer.setOutputFileName("test.pdf");

      QPainter painter;
      painter.begin(&printer);

      painter.drawText( 200,200, "HELLO" );
      painter.end();

[mrjj]

and you also searched for test.pdf to make sure
its not created any where else ?

[TheCipo76]

@mrjj

[mrjj]

@TheCipo76
Very odd.
Can you try this code. it let u select save location
if that dont work. something up with your Qt.

void printv4() {
  QPrinter printer(QPrinter::HighResolution);
  printer.setOrientation(QPrinter::Landscape);
  printer.setOutputFormat(QPrinter::PdfFormat);
  printer.setPaperSize(QPrinter::A4);
  QString fileName = QFileDialog::getSaveFileName(0,"file", "c:\\", "pdf (*.pdf)");
  printer.setOutputFileName(fileName);

  QPainter painter;
  painter.begin(&printer);

  painter.drawText( 200,200, "HELLO" );
  painter.end();

}

[TheCipo76]

@mrjj

Finally works!!!!!! Great!!!
I don't know why but Works!!!!

Thank you very much!!

[TheCipo76]

This post is deleted!

[mrjj]

Super :)
So on mac it seems the file go somewhere else
if no path. maybe a read only place.
So when we tell the exact location , it does work :)

[mpergand]

@TheCipo76 said in Create a PDF from Qt Creator:

printer.setOutputFileName("PrimoPDF.pdf");

When launched from QtCreator, the default working directory is set to:
MyApp/Contents/MacOS/

When launched from the finder, the path is usely the user directory, but actualy it is the root directory (/) and obviously nothing is written (wrong permissions)

[J.Hilk]

@mrjj said in Create a PDF from Qt Creator:

Super :)
So on mac it seems the file go somewhere else if no path

IIRC the standard path is

/Users/yourUserName/Library/Application Support

[dan1973]

Hi,

I was following your comments and conversation. I need to know how to draw lines in PDF document using Qt.

[jsulm]

@dan1973 said in Create a PDF from Qt Creator:

I need to know how to draw lines in PDF document using Qt

https://doc.qt.io/qt-5/qpainter.html#drawLine-2