QWebEnginePage::printToPdf creates empy page

Tarae

My Html2Pdf program:

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);

    // arguments
    QString inputPath = argv[1];
    QString outputPath = argv[2];

    // read input file
    QFile inputFile(inputPath);
    inputFile.open(QIODevice::ReadOnly | QIODevice::Text);
    QTextStream in(&inputFile);
    QString html = in.readAll();

    // get input file directory
    QFileInfo inputFileInfo(inputFile);
    QDir inputFileDir = inputFileInfo.dir();

    // prepare page
    QWebEnginePage page;
    QObject::connect(&page, &QWebEnginePage::pdfPrintingFinished, []{exit(0);});
    page.setHtml(html, inputFileDir.path());

    //print page
    page.printToPdf(outputPath);

    return app.exec();
}

And it doesn't work. It produces pdf file containing one empy page. What do I do wrong?

jsulm

@Tarae My guess is: you need to wait until the HTML page is loaded.
https://doc.qt.io/qt-5/qwebenginepage.html#loadFinished

JonB

@Tarae
I know from experience that what @jsulm says is indeed the case! QWebEnginePage loads asynchronously, if you set off a page print before that's completed you get how the page is now --- which is empty :)

Tarae

@jsulm @JonB Thank you! This works:

QWebEnginePage page;
Object::connect(&page, &QWebEnginePage::pdfPrintingFinished, []{exit(0);});
QObject::connect(&page, &QWebEnginePage::loadFinished, [&page, &outputPath](bool ok){if (ok) page.printToPdf(outputPath);});
page.setHtml(html, inputFileDir.path());