Qt学习1

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QMenu *fileMenu;

QMenu *editMenu;

QMenu *helpMenu;

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void MainWindow::createActions()

//! [17] //! [18]

{

    newAct = new QAction(QIcon(":/images/new.png"), tr("&New"), this);

    newAct->setShortcuts(QKeySequence::New);

    newAct->setStatusTip(tr("Create a new file"));

    connect(newAct, SIGNAL(triggered()), this, SLOT(newFile()));

//! [19]

    openAct = new QAction(QIcon(":/images/open.png"), tr("&Open..."), this);

    openAct->setShortcuts(QKeySequence::Open);

    openAct->setStatusTip(tr("Open an existing file"));

    connect(openAct, SIGNAL(triggered()), this, SLOT(open()));

}

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fileMenu = menuBar()->addMenu(tr("&File"));

    fileMenu->addAction(newAct);

//! [28]

    fileMenu->addAction(openAct);

//! [28]

    fileMenu->addAction(saveAct);

//! [26]

    fileMenu->addAction(saveAsAct);

    fileMenu->addSeparator();

    fileMenu->addAction(exitAct);

    editMenu = menuBar()->addMenu(tr("&Edit"));

    editMenu->addAction(cutAct);

    editMenu->addAction(copyAct);

    editMenu->addAction(pasteAct);

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fileToolBar = addToolBar(tr("File"));

    fileToolBar->addAction(newAct);

//! [29] //! [31]

    fileToolBar->addAction(openAct);

//! [31]

    fileToolBar->addAction(saveAct);

    editToolBar = addToolBar(tr("Edit"));

    editToolBar->addAction(cutAct);

    editToolBar->addAction(copyAct);

    editToolBar->addAction(pasteAct);

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QSettings settings("QtProject", "Application Example");

settings.setValue("pos", pos());

settings.setValue("size", size());

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QSettings settings("QtProject", "Application Example");

QPoint pos = settings.value("pos", QPoint(200, 200)).toPoint();

QSize size = settings.value("size", QSize(400, 400)).toSize();

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void MainWindow::open()

//! [7] //! [8]

{

    if (maybeSave()) {

        QString fileName = QFileDialog::getOpenFileName(this);

        if (!fileName.isEmpty())

            loadFile(fileName);

    }

}

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void MainWindow::loadFile(const QString &fileName)

//! [42] //! [43]

{

    QFile file(fileName);

    if (!file.open(QFile::ReadOnly | QFile::Text)) {

        QMessageBox::warning(this, tr("Application"),

                             tr("Cannot read file %1:\n%2.")

                             .arg(fileName)

                             .arg(file.errorString()));

        return;

    }

    QTextStream in(&file);

#ifndef QT_NO_CURSOR

    QApplication::setOverrideCursor(Qt::WaitCursor);

#endif

    textEdit->setPlainText(in.readAll());

#ifndef QT_NO_CURSOR

    QApplication::restoreOverrideCursor();

#endif

    setCurrentFile(fileName);

    statusBar()->showMessage(tr("File loaded"), 2000);

}

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bool MainWindow::saveAs()

//! [11] //! [12]

{

    QString fileName = QFileDialog::getSaveFileName(this);

    if (fileName.isEmpty())

        return false;

    return saveFile(fileName);

}

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bool MainWindow::saveFile(const QString &fileName)

//! [44] //! [45]

{

    QFile file(fileName);

    if (!file.open(QFile::WriteOnly | QFile::Text)) {

        QMessageBox::warning(this, tr("Application"),

                             tr("Cannot write file %1:\n%2.")

                             .arg(fileName)

                             .arg(file.errorString()));

        return false;

    }

    QTextStream out(&file);

#ifndef QT_NO_CURSOR

    QApplication::setOverrideCursor(Qt::WaitCursor);

#endif

    out << textEdit->toPlainText();

#ifndef QT_NO_CURSOR

    QApplication::restoreOverrideCursor();

#endif

    setCurrentFile(fileName);

    statusBar()->showMessage(tr("File saved"), 2000);

    return true;

}