Qt 5.11 | Qt WebEngine | WebEngine Content Manipulation Example | mainwindow.cpp Example File

Qt 5.11.3 Reference Documentation

# mainwindow.cpp Example File

webenginewidgets/contentmanipulation/mainwindow.cpp

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

      MainWindow::MainWindow(const QUrl& url)
      {
          setAttribute(Qt::WA_DeleteOnClose, true);
          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, &QWebEngineView::loadFinished, this, &MainWindow::adjustLocation);
          connect(view, &QWebEngineView::titleChanged, this, &MainWindow::adjustTitle);
          connect(view, &QWebEngineView::loadProgress, this, &MainWindow::setProgress);
          connect(view, &QWebEngineView::loadFinished, this, &MainWindow::finishLoading);

          locationEdit = new QLineEdit(this);
          locationEdit->setSizePolicy(QSizePolicy::Expanding, locationEdit->sizePolicy().verticalPolicy());
          connect(locationEdit, &QLineEdit::returnPressed, this, &MainWindow::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(tr("Page Source"), this);
          connect(viewSourceAction, &QAction::triggered, this, &MainWindow::viewSource);
          viewMenu->addAction(viewSourceAction);

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

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

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

          setCentralWidget(view);
      }

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

          view->page()->toHtml([textEdit](const QString &html){
              textEdit->setPlainText(html);
          });
      }

      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(QStringLiteral("%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 = QStringLiteral("qt.jQuery('a').each( function () { qt.jQuery(this).css('background-color', 'yellow') } )");
          view->page()->runJavaScript(code);
      }

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

          if (invert)
              code = QStringLiteral("qt.jQuery('img').each( function () { qt.jQuery(this).css('transition', 'transform 2s'); qt.jQuery(this).css('transform', 'rotate(180deg)') } )");
          else
              code = QStringLiteral("qt.jQuery('img').each( function () { qt.jQuery(this).css('transition', 'transform 2s'); qt.jQuery(this).css('transform', 'rotate(0deg)') } )");
          view->page()->runJavaScript(code);
      }

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

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

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

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