mainwindow.cpp Example File

webkitwidgets/previewer/mainwindow.cpp
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#include <QtWidgets>
#include <QtWebKitWidgets>
#include "mainwindow.h"

MainWindow::MainWindow()
{
    createActions();
    createMenus();
    centralWidget = new Previewer(this);
    setCentralWidget(centralWidget);

    connect(centralWidget->webView, SIGNAL(loadFinished(bool)),
        this, SLOT(updateTextEdit()));
    setStartupText();
}

void MainWindow::createActions()
{
    openAct = new QAction(tr("&Open..."), this);
    openAct->setShortcuts(QKeySequence::Open);
    openAct->setStatusTip(tr("Open an existing HTML file"));
    connect(openAct, SIGNAL(triggered()), this, SLOT(open()));

    openUrlAct = new QAction(tr("&Open URL..."), this);
    openUrlAct->setShortcut(tr("Ctrl+U"));
    openUrlAct->setStatusTip(tr("Open a URL"));
    connect(openUrlAct, SIGNAL(triggered()), this, SLOT(openUrl()));

    saveAct = new QAction(tr("&Save"), this);
    saveAct->setShortcuts(QKeySequence::Save);
    saveAct->setStatusTip(tr("Save the HTML file to disk"));
    connect(saveAct, SIGNAL(triggered()), this, SLOT(save()));

    exitAct = new QAction(tr("E&xit"), this);
    exitAct->setStatusTip(tr("Exit the application"));
    exitAct->setShortcuts(QKeySequence::Quit);
    connect(exitAct, SIGNAL(triggered()), this, SLOT(close()));

    aboutAct = new QAction(tr("&About"), this);
    aboutAct->setStatusTip(tr("Show the application's About box"));
    connect(aboutAct, SIGNAL(triggered()), this, SLOT(about()));

    aboutQtAct = new QAction(tr("About &Qt"), this);
    aboutQtAct->setStatusTip(tr("Show the Qt library's About box"));
    connect(aboutQtAct, SIGNAL(triggered()), qApp, SLOT(aboutQt()));
}

void MainWindow::createMenus()
{
    fileMenu = menuBar()->addMenu(tr("&File"));
    fileMenu->addAction(openAct);
    fileMenu->addAction(openUrlAct);
    fileMenu->addAction(saveAct);
    fileMenu->addSeparator();
    fileMenu->addAction(exitAct);

    menuBar()->addSeparator();

    helpMenu = menuBar()->addMenu(tr("&Help"));
    helpMenu->addAction(aboutAct);
    helpMenu->addAction(aboutQtAct);
}

void MainWindow::about()
{
    QMessageBox::about(this, tr("About Previewer"),
        tr("The <b>Previewer</b> example demonstrates how to "
           "view HTML documents using a QWebView."));
}

void MainWindow::open()
{
    QString fileName = QFileDialog::getOpenFileName(this);
    if (!fileName.isEmpty()) {
        // read from file
        QFile file(fileName);

        if (!file.open(QIODevice::ReadOnly)) {
            QMessageBox::information(this, tr("Unable to open file"),
                file.errorString());
            return;
        }

        QTextStream out(&file);
        QString output = out.readAll();

        // display contents
        centralWidget->plainTextEdit->setPlainText(output);
        centralWidget->setBaseUrl(QUrl::fromLocalFile(fileName));
    }
}

void MainWindow::openUrl()
{
    bool ok;
    QString url = QInputDialog::getText(this, tr("Enter a URL"),
                  tr("URL:"), QLineEdit::Normal, "http://", &ok);

    if (ok && !url.isEmpty()) {
        centralWidget->webView->setUrl(url);
    }
}

void MainWindow::save()
{
    QString content = centralWidget->plainTextEdit->toPlainText();
    QString fileName = QFileDialog::getSaveFileName(this);

    if (!fileName.isEmpty()) {
        // save to file
        QFile file(fileName);

        if (!file.open(QIODevice::WriteOnly)) {
            QMessageBox::information(this, tr("Unable to open file"),
                file.errorString());
            return;
        }

        QTextStream in(&file);
        in << content;
    }
}

void MainWindow::updateTextEdit()
{
    QWebFrame *mainFrame = centralWidget->webView->page()->mainFrame();
    QString frameText = mainFrame->toHtml();
    centralWidget->plainTextEdit->setPlainText(frameText);
}

void MainWindow::setStartupText()
{
    QString string = "<html><body><h1>HTML Previewer</h1>"
                     " <p>This example shows you how to use QWebView to"
                     " preview HTML data written in a QPlainTextEdit.</p>"
                     " </body></html>";
    centralWidget->webView->setHtml(string);
}