QMainWindow 一般用到的常规函数

创建主函数一般会用到的常规函数

void MainWindow::closeEvent(QCloseEvent *event)
{
    if (okToContinue()) {
        event->accept();
    } else {
        event->ignore();
    }
}

void MainWindow::open()
{
    if (okToContinue()) {
        QString fileName = QFileDialog::getOpenFileName(this,
                                   tr("Open Spreadsheet"), ".",
                                   tr("Spreadsheet files (*.sp)"));
        if (!fileName.isEmpty())
            loadFile(fileName);
    }
}

bool MainWindow::save()
{
    if (curFile.isEmpty()) {
        return saveAs();
    } else {
        return saveFile(curFile);
    }
}

bool MainWindow::saveAs()
{
    QString fileName = QFileDialog::getSaveFileName(this,
                               tr("Save Spreadsheet"), ".",
                               tr("Spreadsheet files (*.sp)"));
    if (fileName.isEmpty())
        return false;

    return saveFile(fileName);
}

bool MainWindow::okToContinue()
{
    if (isWindowModified()) {
        int r = QMessageBox::warning(this, tr("Spreadsheet"),
                        tr("The document has been modified.\n"
                           "Do you want to save your changes?"),
                        QMessageBox::Yes | QMessageBox::No
                        | QMessageBox::Cancel);
        if (r == QMessageBox::Yes) {
            return save();
        } else if (r == QMessageBox::Cancel) {
            return false;
        }
    }
    return true;
}

bool MainWindow::loadFile(const QString &fileName)
{
    if (!spreadsheet->readFile(fileName)) {
        statusBar()->showMessage(tr("Loading canceled"), 2000);
        return false;
    }

    setCurrentFile(fileName);
    statusBar()->showMessage(tr("File loaded"), 2000);
    return true;
}

bool MainWindow::saveFile(const QString &fileName)
{
    if (!spreadsheet->writeFile(fileName)) {
        statusBar()->showMessage(tr("Saving canceled"), 2000);
        return false;
    }

    setCurrentFile(fileName);
    statusBar()->showMessage(tr("File saved"), 2000);
    return true;
}

QString MainWindow::strippedName(const QString &fullFileName)
{
    return QFileInfo(fullFileName).fileName();
}

特别的如果是创建上下文菜单

void MainWindow::createContextMenu()
{
  spreadsheet->addAction(cutAction);
  ....
  spreadsheet->setContextMenuPolicy(Qt::ActionsContextMenu);
}

还有创建工具栏是addToolBar(tr(...))

另外还有针对应用程序的存储设置

void MainWindow::writeSettings()
{
    QSettings settings("Software Inc.", "Spreadsheet");

    settings.setValue("geometry", saveGeometry());
    settings.setValue("recentFiles", recentFiles);
    settings.setValue("showGrid", showGridAction->isChecked());
    settings.setValue("autoRecalc", autoRecalcAction->isChecked());
}
void MainWindow::readSettings()
{
    QSettings settings("Software Inc.", "Spreadsheet");

    restoreGeometry(settings.value("geometry").toByteArray());

    recentFiles = settings.value("recentFiles").toStringList();
    updateRecentFileActions();

    bool showGrid = settings.value("showGrid", true).toBool();
    showGridAction->setChecked(showGrid);

    bool autoRecalc = settings.value("autoRecalc", true).toBool();
    autoRecalcAction->setChecked(autoRecalc);
}

还有就是中央窗口部件一般要处理的写入文件和载入文件

bool Spreadsheet::writeFile(const QString &fileName)
{
    QFile file(fileName);
    if (!file.open(QIODevice::WriteOnly)) {
        QMessageBox::warning(this, tr("Spreadsheet"),
                             tr("Cannot write file %1:\n%2.")
                             .arg(file.fileName())
                             .arg(file.errorString()));
        return false;
    }

    QDataStream out(&file);
    out.setVersion(QDataStream::Qt_4_3);

    out << quint32(MagicNumber);

    QApplication::setOverrideCursor(Qt::WaitCursor);
    for (int row = 0; row < RowCount; ++row) {
        for (int column = 0; column < ColumnCount; ++column) {
            QString str = formula(row, column);
            if (!str.isEmpty())
                out << quint16(row) << quint16(column) << str;
        }
    }
    QApplication::restoreOverrideCursor();
    return true;
}

bool Spreadsheet::readFile(const QString &fileName)
{
    QFile file(fileName);
    if (!file.open(QIODevice::ReadOnly)) {
        QMessageBox::warning(this, tr("Spreadsheet"),
                             tr("Cannot read file %1:\n%2.")
                             .arg(file.fileName())
                             .arg(file.errorString()));
        return false;
    }

    QDataStream in(&file);
    in.setVersion(QDataStream::Qt_4_3);

    quint32 magic;
    in >> magic;
    if (magic != MagicNumber) {
        QMessageBox::warning(this, tr("Spreadsheet"),
                             tr("The file is not a Spreadsheet file."));
        return false;
    }

    clear();

    quint16 row;
    quint16 column;
    QString str;

    QApplication::setOverrideCursor(Qt::WaitCursor);
    while (!in.atEnd()) {
        in >> row >> column >> str;
        setFormula(row, column, str);
    }
    QApplication::restoreOverrideCursor();
    return true;
}