printhandler.cpp Example File

webenginewidgets/printme/printhandler.cpp
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 #include "printhandler.h"
 #include <QEventLoop>
 #include <QPrintDialog>
 #include <QPrinter>
 #include <QPainter>
 #include <QPrintPreviewDialog>
 #include <QWebEnginePage>

 PrintHandler::PrintHandler(QObject *parent)
     : QObject(parent)
 {

 }

 void PrintHandler::setPage(QWebEnginePage *page)
 {
     Q_ASSERT(!m_page);
     m_page = page;
     connect(m_page, &QWebEnginePage::printRequested, this, &PrintHandler::printPreview);
 }

 void PrintHandler::print()
 {
     QPrinter printer(QPrinter::HighResolution);
     QPrintDialog dialog(&printer, m_page->view());
     if (dialog.exec() != QDialog::Accepted)
         return;
     printDocument(&printer);
 }

 void PrintHandler::printDocument(QPrinter *printer)
 {
     QEventLoop loop;
     bool result;
     auto printPreview = [&](bool success) { result = success; loop.quit(); };
     m_page->print(printer, std::move(printPreview));
     loop.exec();
     if (!result) {
         QPainter painter;
         if (painter.begin(printer)) {
             QFont font = painter.font();
             font.setPixelSize(20);
             painter.setFont(font);
             painter.drawText(QPointF(10,25),
                              QStringLiteral("Could not generate print preview."));

             painter.end();
         }
     }
 }

 void PrintHandler::printPreview()
 {
     if (!m_page)
         return;
     if (m_inPrintPreview)
         return;
     m_inPrintPreview = true;
     QPrinter printer;
     QPrintPreviewDialog preview(&printer, m_page->view());
     connect(&preview, &QPrintPreviewDialog::paintRequested,
             this, &PrintHandler::printDocument);
     preview.exec();
     m_inPrintPreview = false;
 }