Remove the 'sdi' example

It is essentially the same as the other mainwindow examples, showing
how to create a text editor. The only special code here is the tiling of
the different main windows, which - without any documentation or
explanation - is neither very helpful, nor relevant in 2023.

Change-Id: I48b92b1cf057f586e0d2842d1c0a3312154e9a13
Reviewed-by: Axel Spoerl <axel.spoerl@qt.io>
(cherry picked from commit 3c104c279911419f3d0a9e6f3ac050e6f3968e7e)
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

examples/widgets/doc/src/application.qdoc

@@ -27,9 +27,8 @@
     To keep the example simple, recently opened files aren't shown in
     the \uicontrol{File} menu, even though this feature is desired in 90%
     of applications. Furthermore, this example can only load one file at a
-    time. The \l{mainwindows/sdi}{SDI} and \l{mainwindows/mdi}{MDI} examples
+    time. The \l{mainwindows/mdi}{MDI} example shows how to lift these
-    show how to lift these restrictions and how to implement recently opened files
+    restrictions and how to implement recently opened files handling.
-    handling.
 
     \section1 MainWindow Class Definition
 

examples/widgets/doc/src/sdi.qdoc

@@ -1,13 +0,0 @@
-// Copyright (C) 2016 The Qt Company Ltd.
-// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
-
-/*!
-    \example mainwindows/sdi
-    \title SDI Example
-    \ingroup examples-mainwindow
-
-    \brief The SDI example shows how to create a Single Document Interface. It uses a number of
-    top-level windows to display the contents of different text files.
-
-    \image sdi-example.png
-*/

examples/widgets/mainwindows/CMakeLists.txt

@@ -6,4 +6,3 @@ qt_internal_add_example(dockwidgets)
 qt_internal_add_example(mainwindow)
 qt_internal_add_example(mdi)
 qt_internal_add_example(menus)
-qt_internal_add_example(sdi)

examples/widgets/mainwindows/mainwindows.pro

@@ -3,5 +3,4 @@ SUBDIRS       = application \
 		dockwidgets \
                 mainwindow \
                 mdi \
-                menus \
+                menus
-                sdi

examples/widgets/mainwindows/sdi/CMakeLists.txt

@@ -1,54 +0,0 @@
-# Copyright (C) 2022 The Qt Company Ltd.
-# SPDX-License-Identifier: BSD-3-Clause
-
-cmake_minimum_required(VERSION 3.16)
-project(sdi LANGUAGES CXX)
-
-if(NOT DEFINED INSTALL_EXAMPLESDIR)
-    set(INSTALL_EXAMPLESDIR "examples")
-endif()
-
-set(INSTALL_EXAMPLEDIR "${INSTALL_EXAMPLESDIR}/widgets/mainwindows/sdi")
-
-find_package(Qt6 REQUIRED COMPONENTS Core Gui Widgets)
-
-qt_standard_project_setup()
-
-qt_add_executable(sdi
-    main.cpp
-    mainwindow.cpp mainwindow.h
-)
-
-set_target_properties(sdi PROPERTIES
-    WIN32_EXECUTABLE TRUE
-    MACOSX_BUNDLE TRUE
-)
-
-target_link_libraries(sdi PRIVATE
-    Qt6::Core
-    Qt6::Gui
-    Qt6::Widgets
-)
-
-# Resources:
-set(sdi_resource_files
-    "images/copy.png"
-    "images/cut.png"
-    "images/new.png"
-    "images/open.png"
-    "images/paste.png"
-    "images/save.png"
-)
-
-qt_add_resources(sdi "sdi"
-    PREFIX
-        "/"
-    FILES
-        ${sdi_resource_files}
-)
-
-install(TARGETS sdi
-    RUNTIME DESTINATION "${INSTALL_EXAMPLEDIR}"
-    BUNDLE DESTINATION "${INSTALL_EXAMPLEDIR}"
-    LIBRARY DESTINATION "${INSTALL_EXAMPLEDIR}"
-)

examples/widgets/mainwindows/sdi/main.cpp

@@ -1,37 +0,0 @@
-// Copyright (C) 2016 The Qt Company Ltd.
-// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
-
-#include <QApplication>
-#include <QCommandLineParser>
-
-#include "mainwindow.h"
-
-int main(int argc, char *argv[])
-{
-    Q_INIT_RESOURCE(sdi);
-    QApplication app(argc, argv);
-    QCoreApplication::setApplicationName("SDI Example");
-    QCoreApplication::setOrganizationName("QtProject");
-    QCoreApplication::setApplicationVersion(QT_VERSION_STR);
-    QCommandLineParser parser;
-    parser.setApplicationDescription(QCoreApplication::applicationName());
-    parser.addHelpOption();
-    parser.addVersionOption();
-    parser.addPositionalArgument("file", "The file(s) to open.");
-    parser.process(app);
-
-    MainWindow *mainWin = nullptr;
-    const QStringList posArgs = parser.positionalArguments();
-    for (const QString &file : posArgs) {
-        MainWindow *newWin = new MainWindow(file);
-        newWin->tile(mainWin);
-        newWin->show();
-        mainWin = newWin;
-    }
-
-    if (!mainWin)
-        mainWin = new MainWindow;
-    mainWin->show();
-
-    return app.exec();
-}

examples/widgets/mainwindows/sdi/mainwindow.cpp

@@ -1,443 +0,0 @@
-// Copyright (C) 2016 The Qt Company Ltd.
-// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
-
-#include <QtWidgets>
-
-#include "mainwindow.h"
-
-MainWindow::MainWindow()
-{
-    init();
-    setCurrentFile(QString());
-}
-
-MainWindow::MainWindow(const QString &fileName)
-{
-    init();
-    loadFile(fileName);
-}
-
-void MainWindow::closeEvent(QCloseEvent *event)
-{
-    if (maybeSave()) {
-        writeSettings();
-        event->accept();
-    } else {
-        event->ignore();
-    }
-}
-
-void MainWindow::newFile()
-{
-    MainWindow *other = new MainWindow;
-    other->tile(this);
-    other->show();
-}
-
-void MainWindow::open()
-{
-    const QString fileName = QFileDialog::getOpenFileName(this);
-    if (!fileName.isEmpty())
-        openFile(fileName);
-}
-
-void MainWindow::openFile(const QString &fileName)
-{
-    MainWindow *existing = findMainWindow(fileName);
-    if (existing) {
-        existing->show();
-        existing->raise();
-        existing->activateWindow();
-        return;
-    }
-
-    if (isUntitled && textEdit->document()->isEmpty() && !isWindowModified()) {
-        loadFile(fileName);
-        return;
-    }
-
-    MainWindow *other = new MainWindow(fileName);
-    if (other->isUntitled) {
-        delete other;
-        return;
-    }
-    other->tile(this);
-    other->show();
-}
-
-bool MainWindow::save()
-{
-    return isUntitled ? saveAs() : saveFile(curFile);
-}
-
-bool MainWindow::saveAs()
-{
-    QString fileName = QFileDialog::getSaveFileName(this, tr("Save As"),
-                                                    curFile);
-    if (fileName.isEmpty())
-        return false;
-
-    return saveFile(fileName);
-}
-
-void MainWindow::about()
-{
-   QMessageBox::about(this, tr("About SDI"),
-            tr("The <b>SDI</b> example demonstrates how to write single "
-               "document interface applications using Qt."));
-}
-
-void MainWindow::documentWasModified()
-{
-    setWindowModified(true);
-}
-
-void MainWindow::init()
-{
-    setAttribute(Qt::WA_DeleteOnClose);
-
-    isUntitled = true;
-
-    textEdit = new QTextEdit;
-    setCentralWidget(textEdit);
-
-    createActions();
-    createStatusBar();
-
-    readSettings();
-
-    connect(textEdit->document(), &QTextDocument::contentsChanged,
-            this, &MainWindow::documentWasModified);
-
-    setUnifiedTitleAndToolBarOnMac(true);
-}
-
-void MainWindow::tile(const QMainWindow *previous)
-{
-    if (!previous)
-        return;
-    int topFrameWidth = previous->geometry().top() - previous->pos().y();
-    if (!topFrameWidth)
-        topFrameWidth = 40;
-    const QPoint pos = previous->pos() + 2 * QPoint(topFrameWidth, topFrameWidth);
-    if (screen()->availableGeometry().contains(rect().bottomRight() + pos))
-        move(pos);
-}
-
-void MainWindow::createActions()
-{
-    QMenu *fileMenu = menuBar()->addMenu(tr("&File"));
-    QToolBar *fileToolBar = addToolBar(tr("File"));
-
-    const QIcon newIcon = QIcon::fromTheme("document-new", QIcon(":/images/new.png"));
-    QAction *newAct = new QAction(newIcon, tr("&New"), this);
-    newAct->setShortcuts(QKeySequence::New);
-    newAct->setStatusTip(tr("Create a new file"));
-    connect(newAct, &QAction::triggered, this, &MainWindow::newFile);
-    fileMenu->addAction(newAct);
-    fileToolBar->addAction(newAct);
-
-    const QIcon openIcon = QIcon::fromTheme("document-open", QIcon(":/images/open.png"));
-    QAction *openAct = new QAction(openIcon, tr("&Open..."), this);
-    openAct->setShortcuts(QKeySequence::Open);
-    openAct->setStatusTip(tr("Open an existing file"));
-    connect(openAct, &QAction::triggered, this, &MainWindow::open);
-    fileMenu->addAction(openAct);
-    fileToolBar->addAction(openAct);
-
-    const QIcon saveIcon = QIcon::fromTheme("document-save", QIcon(":/images/save.png"));
-    QAction *saveAct = new QAction(saveIcon, tr("&Save"), this);
-    saveAct->setShortcuts(QKeySequence::Save);
-    saveAct->setStatusTip(tr("Save the document to disk"));
-    connect(saveAct, &QAction::triggered, this, &MainWindow::save);
-    fileMenu->addAction(saveAct);
-    fileToolBar->addAction(saveAct);
-
-    const QIcon saveAsIcon = QIcon::fromTheme("document-save-as");
-    QAction *saveAsAct = fileMenu->addAction(saveAsIcon, tr("Save &As..."), this, &MainWindow::saveAs);
-    saveAsAct->setShortcuts(QKeySequence::SaveAs);
-    saveAsAct->setStatusTip(tr("Save the document under a new name"));
-
-    fileMenu->addSeparator();
-
-    QMenu *recentMenu = fileMenu->addMenu(tr("Recent..."));
-    connect(recentMenu, &QMenu::aboutToShow, this, &MainWindow::updateRecentFileActions);
-    recentFileSubMenuAct = recentMenu->menuAction();
-
-    for (int i = 0; i < MaxRecentFiles; ++i) {
-        recentFileActs[i] = recentMenu->addAction(QString(), this, &MainWindow::openRecentFile);
-        recentFileActs[i]->setVisible(false);
-    }
-
-    recentFileSeparator = fileMenu->addSeparator();
-
-    setRecentFilesVisible(MainWindow::hasRecentFiles());
-
-    QAction *closeAct = fileMenu->addAction(tr("&Close"), this, &QWidget::close);
-    closeAct->setShortcut(tr("Ctrl+W"));
-    closeAct->setStatusTip(tr("Close this window"));
-
-    const QIcon exitIcon = QIcon::fromTheme("application-exit");
-    QAction *exitAct = fileMenu->addAction(exitIcon, tr("E&xit"), qApp, &QApplication::quit);
-    exitAct->setShortcuts(QKeySequence::Quit);
-    exitAct->setStatusTip(tr("Exit the application"));
-
-    QMenu *editMenu = menuBar()->addMenu(tr("&Edit"));
-    QToolBar *editToolBar = addToolBar(tr("Edit"));
-
-#ifndef QT_NO_CLIPBOARD
-    const QIcon cutIcon = QIcon::fromTheme("edit-cut", QIcon(":/images/cut.png"));
-    QAction *cutAct = new QAction(cutIcon, tr("Cu&t"), this);
-    cutAct->setShortcuts(QKeySequence::Cut);
-    cutAct->setStatusTip(tr("Cut the current selection's contents to the "
-                            "clipboard"));
-    connect(cutAct, &QAction::triggered, textEdit, &QTextEdit::cut);
-    editMenu->addAction(cutAct);
-    editToolBar->addAction(cutAct);
-
-    const QIcon copyIcon = QIcon::fromTheme("edit-copy", QIcon(":/images/copy.png"));
-    QAction *copyAct = new QAction(copyIcon, tr("&Copy"), this);
-    copyAct->setShortcuts(QKeySequence::Copy);
-    copyAct->setStatusTip(tr("Copy the current selection's contents to the "
-                             "clipboard"));
-    connect(copyAct, &QAction::triggered, textEdit, &QTextEdit::copy);
-    editMenu->addAction(copyAct);
-    editToolBar->addAction(copyAct);
-
-    const QIcon pasteIcon = QIcon::fromTheme("edit-paste", QIcon(":/images/paste.png"));
-    QAction *pasteAct = new QAction(pasteIcon, tr("&Paste"), this);
-    pasteAct->setShortcuts(QKeySequence::Paste);
-    pasteAct->setStatusTip(tr("Paste the clipboard's contents into the current "
-                              "selection"));
-    connect(pasteAct, &QAction::triggered, textEdit, &QTextEdit::paste);
-    editMenu->addAction(pasteAct);
-    editToolBar->addAction(pasteAct);
-
-    menuBar()->addSeparator();
-#endif // !QT_NO_CLIPBOARD
-
-    QMenu *helpMenu = menuBar()->addMenu(tr("&Help"));
-    QAction *aboutAct = helpMenu->addAction(tr("&About"), this, &MainWindow::about);
-    aboutAct->setStatusTip(tr("Show the application's About box"));
-
-    QAction *aboutQtAct = helpMenu->addAction(tr("About &Qt"), qApp, &QApplication::aboutQt);
-    aboutQtAct->setStatusTip(tr("Show the Qt library's About box"));
-
-#ifndef QT_NO_CLIPBOARD
-    cutAct->setEnabled(false);
-    copyAct->setEnabled(false);
-    connect(textEdit, &QTextEdit::copyAvailable, cutAct, &QAction::setEnabled);
-    connect(textEdit, &QTextEdit::copyAvailable, copyAct, &QAction::setEnabled);
-#endif // !QT_NO_CLIPBOARD
-}
-
-void MainWindow::createStatusBar()
-{
-    statusBar()->showMessage(tr("Ready"));
-}
-
-void MainWindow::readSettings()
-{
-    QSettings settings(QCoreApplication::organizationName(), QCoreApplication::applicationName());
-    const QByteArray geometry = settings.value("geometry", QByteArray()).toByteArray();
-    if (geometry.isEmpty()) {
-        const QRect availableGeometry = screen()->availableGeometry();
-        resize(availableGeometry.width() / 3, availableGeometry.height() / 2);
-        move((availableGeometry.width() - width()) / 2,
-             (availableGeometry.height() - height()) / 2);
-    } else {
-        restoreGeometry(geometry);
-    }
-}
-
-void MainWindow::writeSettings()
-{
-    QSettings settings(QCoreApplication::organizationName(), QCoreApplication::applicationName());
-    settings.setValue("geometry", saveGeometry());
-}
-
-bool MainWindow::maybeSave()
-{
-    if (!textEdit->document()->isModified())
-        return true;
-    const QMessageBox::StandardButton ret
-        = QMessageBox::warning(this, tr("SDI"),
-                               tr("The document has been modified.\n"
-                                  "Do you want to save your changes?"),
-                               QMessageBox::Save | QMessageBox::Discard
-                               | QMessageBox::Cancel);
-    switch (ret) {
-    case QMessageBox::Save:
-        return save();
-    case QMessageBox::Cancel:
-        return false;
-    default:
-        break;
-    }
-    return true;
-}
-
-void MainWindow::loadFile(const QString &fileName)
-{
-
-    QFile file(fileName);
-    if (!file.open(QFile::ReadOnly | QFile::Text)) {
-        QMessageBox::warning(this, tr("SDI"),
-                             tr("Cannot read file %1:\n%2.")
-                             .arg(QDir::toNativeSeparators(fileName), file.errorString()));
-        return;
-    }
-
-    QTextStream in(&file);
-    QGuiApplication::setOverrideCursor(Qt::WaitCursor);
-    textEdit->setPlainText(in.readAll());
-    QGuiApplication::restoreOverrideCursor();
-
-    setCurrentFile(fileName);
-    statusBar()->showMessage(tr("File loaded"), 2000);
-}
-
-void MainWindow::setRecentFilesVisible(bool visible)
-{
-    recentFileSubMenuAct->setVisible(visible);
-    recentFileSeparator->setVisible(visible);
-}
-
-static inline QString recentFilesKey() { return QStringLiteral("recentFileList"); }
-static inline QString fileKey() { return QStringLiteral("file"); }
-
-static QStringList readRecentFiles(QSettings &settings)
-{
-    QStringList result;
-    const int count = settings.beginReadArray(recentFilesKey());
-    for (int i = 0; i < count; ++i) {
-        settings.setArrayIndex(i);
-        result.append(settings.value(fileKey()).toString());
-    }
-    settings.endArray();
-    return result;
-}
-
-static void writeRecentFiles(const QStringList &files, QSettings &settings)
-{
-    const int count = files.size();
-    settings.beginWriteArray(recentFilesKey());
-    for (int i = 0; i < count; ++i) {
-        settings.setArrayIndex(i);
-        settings.setValue(fileKey(), files.at(i));
-    }
-    settings.endArray();
-}
-
-bool MainWindow::hasRecentFiles()
-{
-    QSettings settings(QCoreApplication::organizationName(), QCoreApplication::applicationName());
-    const int count = settings.beginReadArray(recentFilesKey());
-    settings.endArray();
-    return count > 0;
-}
-
-void MainWindow::prependToRecentFiles(const QString &fileName)
-{
-    QSettings settings(QCoreApplication::organizationName(), QCoreApplication::applicationName());
-
-    const QStringList oldRecentFiles = readRecentFiles(settings);
-    QStringList recentFiles = oldRecentFiles;
-    recentFiles.removeAll(fileName);
-    recentFiles.prepend(fileName);
-    if (oldRecentFiles != recentFiles)
-        writeRecentFiles(recentFiles, settings);
-
-    setRecentFilesVisible(!recentFiles.isEmpty());
-}
-
-void MainWindow::updateRecentFileActions()
-{
-    QSettings settings(QCoreApplication::organizationName(), QCoreApplication::applicationName());
-
-    const QStringList recentFiles = readRecentFiles(settings);
-    const int count = qMin(int(MaxRecentFiles), recentFiles.size());
-    int i = 0;
-    for ( ; i < count; ++i) {
-        const QString fileName = MainWindow::strippedName(recentFiles.at(i));
-        recentFileActs[i]->setText(tr("&%1 %2").arg(i + 1).arg(fileName));
-        recentFileActs[i]->setData(recentFiles.at(i));
-        recentFileActs[i]->setVisible(true);
-    }
-    for ( ; i < MaxRecentFiles; ++i)
-        recentFileActs[i]->setVisible(false);
-}
-
-void MainWindow::openRecentFile()
-{
-    if (const QAction *action = qobject_cast<const QAction *>(sender()))
-        openFile(action->data().toString());
-}
-
-bool MainWindow::saveFile(const QString &fileName)
-{
-    QString errorMessage;
-
-    QGuiApplication::setOverrideCursor(Qt::WaitCursor);
-    QSaveFile file(fileName);
-    if (file.open(QFile::WriteOnly | QFile::Text)) {
-        QTextStream out(&file);
-        out << textEdit->toPlainText();
-        if (!file.commit()) {
-            errorMessage = tr("Cannot write file %1:\n%2.")
-                           .arg(QDir::toNativeSeparators(fileName), file.errorString());
-        }
-    } else {
-        errorMessage = tr("Cannot open file %1 for writing:\n%2.")
-                       .arg(QDir::toNativeSeparators(fileName), file.errorString());
-    }
-    QGuiApplication::restoreOverrideCursor();
-
-    if (!errorMessage.isEmpty()) {
-        QMessageBox::warning(this, tr("SDI"), errorMessage);
-        return false;
-    }
-
-    setCurrentFile(fileName);
-    statusBar()->showMessage(tr("File saved"), 2000);
-    return true;
-}
-
-void MainWindow::setCurrentFile(const QString &fileName)
-{
-    static int sequenceNumber = 1;
-
-    isUntitled = fileName.isEmpty();
-    if (isUntitled) {
-        curFile = tr("document%1.txt").arg(sequenceNumber++);
-    } else {
-        curFile = QFileInfo(fileName).canonicalFilePath();
-    }
-
-    textEdit->document()->setModified(false);
-    setWindowModified(false);
-
-    if (!isUntitled && windowFilePath() != curFile)
-        MainWindow::prependToRecentFiles(curFile);
-
-    setWindowFilePath(curFile);
-}
-
-QString MainWindow::strippedName(const QString &fullFileName)
-{
-    return QFileInfo(fullFileName).fileName();
-}
-
-MainWindow *MainWindow::findMainWindow(const QString &fileName) const
-{
-    QString canonicalFilePath = QFileInfo(fileName).canonicalFilePath();
-
-    const QList<QWidget *> topLevelWidgets = QApplication::topLevelWidgets();
-    for (QWidget *widget : topLevelWidgets) {
-        MainWindow *mainWin = qobject_cast<MainWindow *>(widget);
-        if (mainWin && mainWin->curFile == canonicalFilePath)
-            return mainWin;
-    }
-
-    return nullptr;
-}

examples/widgets/mainwindows/sdi/mainwindow.h

@@ -1,70 +0,0 @@
-// Copyright (C) 2016 The Qt Company Ltd.
-// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
-
-#ifndef MAINWINDOW_H
-#define MAINWINDOW_H
-
-#include <QMainWindow>
-#include <QList>
-
-QT_BEGIN_NAMESPACE
-class QAction;
-class QMenu;
-class QTextEdit;
-QT_END_NAMESPACE
-
-//! [class definition with macro]
-class MainWindow : public QMainWindow
-{
-    Q_OBJECT
-
-public:
-    MainWindow();
-//! [class definition with macro]
-    explicit MainWindow(const QString &fileName);
-
-    void tile(const QMainWindow *previous);
-
-protected:
-    void closeEvent(QCloseEvent *event) override;
-
-private slots:
-    void newFile();
-    void open();
-    bool save();
-    bool saveAs();
-    void updateRecentFileActions();
-    void openRecentFile();
-    void about();
-    void documentWasModified();
-
-private:
-    enum { MaxRecentFiles = 5 };
-
-    void init();
-    void createActions();
-    void createStatusBar();
-    void readSettings();
-    void writeSettings();
-    bool maybeSave();
-    void openFile(const QString &fileName);
-    void loadFile(const QString &fileName);
-    static bool hasRecentFiles();
-    void prependToRecentFiles(const QString &fileName);
-    void setRecentFilesVisible(bool visible);
-    bool saveFile(const QString &fileName);
-    void setCurrentFile(const QString &fileName);
-    static QString strippedName(const QString &fullFileName);
-    MainWindow *findMainWindow(const QString &fileName) const;
-
-    QTextEdit *textEdit;
-
-    QAction *recentFileActs[MaxRecentFiles];
-    QAction *recentFileSeparator;
-    QAction *recentFileSubMenuAct;
-
-    QString curFile;
-    bool isUntitled;
-};
-
-#endif

examples/widgets/mainwindows/sdi/sdi.pro

@@ -1,11 +0,0 @@
-QT += widgets
-requires(qtConfig(filedialog))
-
-HEADERS       = mainwindow.h
-SOURCES       = main.cpp \
-                mainwindow.cpp
-RESOURCES     = sdi.qrc
-
-# install
-target.path = $$[QT_INSTALL_EXAMPLES]/widgets/mainwindows/sdi
-INSTALLS += target

examples/widgets/mainwindows/sdi/sdi.qrc

@@ -1,10 +0,0 @@
-<!DOCTYPE RCC><RCC version="1.0">
-<qresource>
-    <file>images/copy.png</file>
-    <file>images/cut.png</file>
-    <file>images/new.png</file>
-    <file>images/open.png</file>
-    <file>images/paste.png</file>
-    <file>images/save.png</file>
-</qresource>
-</RCC>

src/widgets/kernel/qwidget.cpp

@@ -11480,7 +11480,7 @@ void QWidgetPrivate::setWindowOpacity_sys(qreal level)
     its parent because other children of the parent might have been
     modified.
 
-    \sa windowTitle, {Qt Widgets - Application Example}, {SDI Example},
+    \sa windowTitle, {Qt Widgets - Application Example},
     {MDI Example}
 */
 bool QWidget::isWindowModified() const

src/widgets/widgets/qmainwindow.cpp

@@ -278,7 +278,7 @@ void QMainWindowPrivate::init()
 
     \sa QMenuBar, QToolBar, QStatusBar, QDockWidget,
     {Qt Widgets - Application Example}, {Dock Widgets Example},
-    {MDI Example}, {SDI Example}, {Menus Example}
+    {MDI Example}, {Menus Example}
 */
 
 /*!