framecapture.cpp Example File

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  #include "framecapture.h"

  #include <iostream>

  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);
  }