mainwindow.cpp Example File

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  #include <QtWidgets>
  #include <QtNetwork>
  #include <QtWebKitWidgets>
  #include "mainwindow.h"


  MainWindow::MainWindow(const QUrl& url)
  {
      progress = 0;

      QFile file;
      file.setFileName("/usr/share/javascript/jquery/jquery.min.js");
      file.open(QIODevice::ReadOnly);
      jQuery = file.readAll();
      jQuery.append("\nvar qt = { 'jQuery': jQuery.noConflict(true) };");
      file.close();

      QNetworkProxyFactory::setUseSystemConfiguration(true);

      view = new QWebView(this);
      view->load(url);
      connect(view, SIGNAL(loadFinished(bool)), SLOT(adjustLocation()));
      connect(view, SIGNAL(titleChanged(QString)), SLOT(adjustTitle()));
      connect(view, SIGNAL(loadProgress(int)), SLOT(setProgress(int)));
      connect(view, SIGNAL(loadFinished(bool)), SLOT(finishLoading(bool)));

      locationEdit = new QLineEdit(this);
      locationEdit->setSizePolicy(QSizePolicy::Expanding, locationEdit->sizePolicy().verticalPolicy());
      connect(locationEdit, SIGNAL(returnPressed()), SLOT(changeLocation()));

      QToolBar *toolBar = addToolBar(tr("Navigation"));
      toolBar->addAction(view->pageAction(QWebPage::Back));
      toolBar->addAction(view->pageAction(QWebPage::Forward));
      toolBar->addAction(view->pageAction(QWebPage::Reload));
      toolBar->addAction(view->pageAction(QWebPage::Stop));
      toolBar->addWidget(locationEdit);

      QMenu *viewMenu = menuBar()->addMenu(tr("&View"));
      QAction* viewSourceAction = new QAction("Page Source", this);
      connect(viewSourceAction, SIGNAL(triggered()), SLOT(viewSource()));
      viewMenu->addAction(viewSourceAction);

      QMenu *effectMenu = menuBar()->addMenu(tr("&Effect"));
      effectMenu->addAction("Highlight all links", this, SLOT(highlightAllLinks()));

      rotateAction = new QAction(this);
      rotateAction->setIcon(style()->standardIcon(QStyle::SP_FileDialogDetailedView));
      rotateAction->setCheckable(true);
      rotateAction->setText(tr("Turn images upside down"));
      connect(rotateAction, SIGNAL(toggled(bool)), this, SLOT(rotateImages(bool)));
      effectMenu->addAction(rotateAction);

      QMenu *toolsMenu = menuBar()->addMenu(tr("&Tools"));
      toolsMenu->addAction(tr("Remove GIF images"), this, SLOT(removeGifImages()));
      toolsMenu->addAction(tr("Remove all inline frames"), this, SLOT(removeInlineFrames()));
      toolsMenu->addAction(tr("Remove all object elements"), this, SLOT(removeObjectElements()));
      toolsMenu->addAction(tr("Remove all embedded elements"), this, SLOT(removeEmbeddedElements()));

      setCentralWidget(view);
      setUnifiedTitleAndToolBarOnMac(true);
  }

  void MainWindow::viewSource()
  {
      QNetworkAccessManager* accessManager = view->page()->networkAccessManager();
      QNetworkRequest request(view->url());
      QNetworkReply* reply = accessManager->get(request);
      connect(reply, SIGNAL(finished()), this, SLOT(slotSourceDownloaded()));
  }

  void MainWindow::slotSourceDownloaded()
  {
      QNetworkReply* reply = qobject_cast<QNetworkReply*>(const_cast<QObject*>(sender()));
      QTextEdit* textEdit = new QTextEdit(NULL);
      textEdit->setAttribute(Qt::WA_DeleteOnClose);
      textEdit->show();
      textEdit->setPlainText(reply->readAll());
      reply->deleteLater();
  }

  void MainWindow::adjustLocation()
  {
      locationEdit->setText(view->url().toString());
  }

  void MainWindow::changeLocation()
  {
      QUrl url = QUrl::fromUserInput(locationEdit->text());
      view->load(url);
      view->setFocus();
  }

  void MainWindow::adjustTitle()
  {
      if (progress <= 0 || progress >= 100)
          setWindowTitle(view->title());
      else
          setWindowTitle(QString("%1 (%2%)").arg(view->title()).arg(progress));
  }

  void MainWindow::setProgress(int p)
  {
      progress = p;
      adjustTitle();
  }

  void MainWindow::finishLoading(bool)
  {
      progress = 100;
      adjustTitle();
      view->page()->mainFrame()->evaluateJavaScript(jQuery);

      rotateImages(rotateAction->isChecked());
  }

  void MainWindow::highlightAllLinks()
  {
      // We append '; undefined' after the jQuery call here to prevent a possible recursion loop and crash caused by
      // the way the elements returned by the each iterator elements reference each other, which causes problems upon
      // converting them to QVariants.
      QString code = "qt.jQuery('a').each( function () { qt.jQuery(this).css('background-color', 'yellow') } ); undefined";
      view->page()->mainFrame()->evaluateJavaScript(code);
  }

  void MainWindow::rotateImages(bool invert)
  {
      QString code;

      // We append '; undefined' after each of the jQuery calls here to prevent a possible recursion loop and crash caused by
      // the way the elements returned by the each iterator elements reference each other, which causes problems upon
      // converting them to QVariants.
      if (invert)
          code = "qt.jQuery('img').each( function () { qt.jQuery(this).css('-webkit-transition', '-webkit-transform 2s'); qt.jQuery(this).css('-webkit-transform', 'rotate(180deg)') } ); undefined";
      else
          code = "qt.jQuery('img').each( function () { qt.jQuery(this).css('-webkit-transition', '-webkit-transform 2s'); qt.jQuery(this).css('-webkit-transform', 'rotate(0deg)') } ); undefined";
      view->page()->mainFrame()->evaluateJavaScript(code);
  }

  void MainWindow::removeGifImages()
  {
      QString code = "qt.jQuery('[src*=gif]').remove()";
      view->page()->mainFrame()->evaluateJavaScript(code);
  }

  void MainWindow::removeInlineFrames()
  {
      QString code = "qt.jQuery('iframe').remove()";
      view->page()->mainFrame()->evaluateJavaScript(code);
  }

  void MainWindow::removeObjectElements()
  {
      QString code = "qt.jQuery('object').remove()";
      view->page()->mainFrame()->evaluateJavaScript(code);
  }

  void MainWindow::removeEmbeddedElements()
  {
      QString code = "qt.jQuery('embed').remove()";
      view->page()->mainFrame()->evaluateJavaScript(code);
  }