mainwindow.cpp Example File

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  #include <QtWidgets>
  #include <QtWebEngineWidgets>
  #include "mainwindow.h"

  template<typename Arg, typename R, typename C>
  struct InvokeWrapper {
      R *receiver;
      void (C::*memberFun)(Arg);
      void operator()(Arg result) {
          (receiver->*memberFun)(result);
      }
  };

  template<typename Arg, typename R, typename C>
  InvokeWrapper<Arg, R, C> invoke(R *receiver, void (C::*memberFun)(Arg))
  {
      InvokeWrapper<Arg, R, C> wrapper = {receiver, memberFun};
      return wrapper;
  }

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

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

      view = new QWebEngineView(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(QWebEnginePage::Back));
      toolBar->addAction(view->pageAction(QWebEnginePage::Forward));
      toolBar->addAction(view->pageAction(QWebEnginePage::Reload));
      toolBar->addAction(view->pageAction(QWebEnginePage::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);
  }

  void MainWindow::viewSource()
  {
      QTextEdit* textEdit = new QTextEdit(NULL);
      textEdit->setAttribute(Qt::WA_DeleteOnClose);
      textEdit->adjustSize();
      textEdit->move(this->geometry().center() - textEdit->rect().center());
      textEdit->show();

      view->page()->toHtml(invoke(textEdit, &QTextEdit::setPlainText));
  }

  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()->runJavaScript(jQuery);

      rotateImages(rotateAction->isChecked());
  }

  void MainWindow::highlightAllLinks()
  {
      QString code = "qt.jQuery('a').each( function () { qt.jQuery(this).css('background-color', 'yellow') } ); undefined";
      view->page()->runJavaScript(code);
  }

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

      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()->runJavaScript(code);
  }

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

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

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

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