Qt Reference Documentation

# framecapture.cpp Example File

webkit/framecapture/framecapture.cpp

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     ** This file is part of the examples of the Qt Toolkit.
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     #include "framecapture.h"

     #include <iostream>
     #include <QtWebKit>

     FrameCapture::FrameCapture(): QObject(), m_percent(0)
     {
         connect(&m_page, SIGNAL(loadProgress(int)), this, SLOT(printProgress(int)));
         connect(&m_page, SIGNAL(loadFinished(bool)), this, SLOT(saveResult(bool)));
     }

     void FrameCapture::load(const QUrl &url, const QString &outputFileName)
     {
         std::cout << "Loading " << qPrintable(url.toString()) << std::endl;
         m_percent = 0;
         int index = outputFileName.lastIndexOf('.');
         m_fileName = (index == -1) ? outputFileName + ".png" : outputFileName;
         m_page.mainFrame()->load(url);
         m_page.mainFrame()->setScrollBarPolicy(Qt::Vertical, Qt::ScrollBarAlwaysOff);
         m_page.mainFrame()->setScrollBarPolicy(Qt::Horizontal, Qt::ScrollBarAlwaysOff);
         m_page.setViewportSize(QSize(1024, 768));
     }

     void FrameCapture::printProgress(int percent)
     {
         if (m_percent >= percent)
             return;

         while (m_percent++ < percent)
             std::cout << "#" << std::flush;
     }

     void FrameCapture::saveResult(bool ok)
     {
         std::cout << std::endl;

         // crude error-checking
         if (!ok) {
             std::cerr << "Failed loading " << qPrintable(m_page.mainFrame()->url().toString()) << std::endl;
             emit finished();
             return;
         }

         // save each frame in different image files
         saveFrame(m_page.mainFrame());

         emit finished();
     }

     void FrameCapture::saveFrame(QWebFrame *frame)
     {
         static int frameCounter = 0;

         QString fileName(m_fileName);
         if (frameCounter) {
             int index = m_fileName.lastIndexOf('.');
             fileName = fileName.insert(index, "_frame" + QString::number(frameCounter));
         }

         QImage image(frame->contentsSize(), QImage::Format_ARGB32_Premultiplied);
         image.fill(Qt::transparent);

         QPainter painter(&image);
         painter.setRenderHint(QPainter::Antialiasing, true);
         painter.setRenderHint(QPainter::TextAntialiasing, true);
         painter.setRenderHint(QPainter::SmoothPixmapTransform, true);
         frame->documentElement().render(&painter);
         painter.end();

         image.save(fileName);

         ++frameCounter;
         foreach(QWebFrame *childFrame, frame->childFrames())
             saveFrame(childFrame);
     }