Polish the settings editor example.

- Set QtProject as organization.
- Remove unneeded member variables.
- Use member initialization in the constructor.
- Use new connection syntax in createActions()
  to assemble the menu there, removing the createMenus()
  function.
- Introduce a QSharedPointer to ensure settings are deleted.
  Previously, the settings were parented on the tree widget,
  which is a hack of sorts.
- Fix OS X macros.

Change-Id: Ibbc6bfb03eb5c7eda077b1a3aa3f1707667f7f13
Reviewed-by: Topi Reiniö <topi.reinio@digia.com>
Reviewed-by: Joerg Bornemann <joerg.bornemann@theqtcompany.com>

7 files changed, 151 insertions, 161 deletions

diff --git a/examples/widgets/tools/settingseditor/locationdialog.cpp b/examples/widgets/tools/settingseditor/locationdialog.cpp
index 31c221f5d9..ad7f7e2ce5 100644
--- a/examples/widgets/tools/settingseditor/locationdialog.cpp
+++ b/examples/widgets/tools/settingseditor/locationdialog.cpp
@@ -54,17 +54,18 @@ LocationDialog::LocationDialog(QWidget *parent)
     scopeComboBox->addItem(tr("System"));
 
     organizationComboBox = new QComboBox;
-    organizationComboBox->addItem(tr("Qt"));
+    organizationComboBox->addItem(tr("QtProject"));
     organizationComboBox->setEditable(true);
 
     applicationComboBox = new QComboBox;
     applicationComboBox->addItem(tr("Any"));
+    applicationComboBox->addItem(tr("Qt Creator"));
     applicationComboBox->addItem(tr("Application Example"));
     applicationComboBox->addItem(tr("Assistant"));
     applicationComboBox->addItem(tr("Designer"));
     applicationComboBox->addItem(tr("Linguist"));
     applicationComboBox->setEditable(true);
-    applicationComboBox->setCurrentIndex(3);
+    applicationComboBox->setCurrentIndex(1);
 
     formatLabel = new QLabel(tr("&Format:"));
     formatLabel->setBuddy(formatComboBox);
@@ -91,28 +92,30 @@ LocationDialog::LocationDialog(QWidget *parent)
     locationsTable->setHorizontalHeaderLabels(labels);
     locationsTable->horizontalHeader()->setSectionResizeMode(0, QHeaderView::Stretch);
     locationsTable->horizontalHeader()->resizeSection(1, 180);
+    connect(locationsTable, &QTableWidget::itemActivated, this, &LocationDialog::itemActivated);
 
-    buttonBox = new QDialogButtonBox(QDialogButtonBox::Ok
-                                     | QDialogButtonBox::Cancel);
+    buttonBox = new QDialogButtonBox(QDialogButtonBox::Ok | QDialogButtonBox::Cancel);
 
-    connect(formatComboBox, SIGNAL(activated(int)),
-            this, SLOT(updateLocationsTable()));
-    connect(scopeComboBox, SIGNAL(activated(int)),
-            this, SLOT(updateLocationsTable()));
+    typedef void (QComboBox::*QComboIntSignal)(int);
+    connect(formatComboBox, static_cast<QComboIntSignal>(&QComboBox::activated),
+            this, &LocationDialog::updateLocationsTable);
+    connect(scopeComboBox, static_cast<QComboIntSignal>(&QComboBox::activated),
+            this, &LocationDialog::updateLocationsTable);
     connect(organizationComboBox->lineEdit(),
-            SIGNAL(editingFinished()),
-            this, SLOT(updateLocationsTable()));
+            &QLineEdit::editingFinished,
+            this, &LocationDialog::updateLocationsTable);
     connect(applicationComboBox->lineEdit(),
-            SIGNAL(editingFinished()),
-            this, SLOT(updateLocationsTable()));
-    connect(buttonBox, SIGNAL(accepted()), this, SLOT(accept()));
-    connect(buttonBox, SIGNAL(rejected()), this, SLOT(reject()));
-
-    QVBoxLayout *locationsLayout = new QVBoxLayout;
+            &QLineEdit::editingFinished,
+            this, &LocationDialog::updateLocationsTable);
+    connect(applicationComboBox, static_cast<QComboIntSignal>(&QComboBox::activated),
+            this, &LocationDialog::updateLocationsTable);
+    connect(buttonBox, &QDialogButtonBox::accepted, this, &QDialog::accept);
+    connect(buttonBox, &QDialogButtonBox::rejected, this, &QDialog::reject);
+
+    QVBoxLayout *locationsLayout = new QVBoxLayout(locationsGroupBox);
     locationsLayout->addWidget(locationsTable);
-    locationsGroupBox->setLayout(locationsLayout);
 
-    QGridLayout *mainLayout = new QGridLayout;
+    QGridLayout *mainLayout = new QGridLayout(this);
     mainLayout->addWidget(formatLabel, 0, 0);
     mainLayout->addWidget(formatComboBox, 0, 1);
     mainLayout->addWidget(scopeLabel, 1, 0);
@@ -123,7 +126,6 @@ LocationDialog::LocationDialog(QWidget *parent)
     mainLayout->addWidget(applicationComboBox, 3, 1);
     mainLayout->addWidget(locationsGroupBox, 4, 0, 1, 2);
     mainLayout->addWidget(buttonBox, 5, 0, 1, 2);
-    setLayout(mainLayout);
 
     updateLocationsTable();
 
@@ -155,11 +157,16 @@ QString LocationDialog::organization() const
 QString LocationDialog::application() const
 {
     if (applicationComboBox->currentText() == tr("Any"))
-        return "";
+        return QString();
     else
         return applicationComboBox->currentText();
 }
 
+void LocationDialog::itemActivated(QTableWidgetItem *)
+{
+    buttonBox->button(QDialogButtonBox::Ok)->animateClick();
+}
+
 void LocationDialog::updateLocationsTable()
 {
     locationsTable->setUpdatesEnabled(false);
@@ -184,8 +191,7 @@ void LocationDialog::updateLocationsTable()
             int row = locationsTable->rowCount();
             locationsTable->setRowCount(row + 1);
 
-            QTableWidgetItem *item0 = new QTableWidgetItem;
-            item0->setText(settings.fileName());
+            QTableWidgetItem *item0 = new QTableWidgetItem(QDir::toNativeSeparators(settings.fileName()));
 
             QTableWidgetItem *item1 = new QTableWidgetItem;
             bool disable = (settings.childKeys().isEmpty()
diff --git a/examples/widgets/tools/settingseditor/locationdialog.h b/examples/widgets/tools/settingseditor/locationdialog.h
index 5bb68d54df..d6f0225a31 100644
--- a/examples/widgets/tools/settingseditor/locationdialog.h
+++ b/examples/widgets/tools/settingseditor/locationdialog.h
@@ -50,6 +50,7 @@ class QDialogButtonBox;
 class QGroupBox;
 class QLabel;
 class QTableWidget;
+class QTableWidgetItem;
 QT_END_NAMESPACE
 
 class LocationDialog : public QDialog
@@ -66,6 +67,7 @@ public:
 
 private slots:
     void updateLocationsTable();
+    void itemActivated(QTableWidgetItem *);
 
 private:
     QLabel *formatLabel;
diff --git a/examples/widgets/tools/settingseditor/main.cpp b/examples/widgets/tools/settingseditor/main.cpp
index 842a474405..0947efd817 100644
--- a/examples/widgets/tools/settingseditor/main.cpp
+++ b/examples/widgets/tools/settingseditor/main.cpp
@@ -45,6 +45,9 @@
 int main(int argc, char *argv[])
 {
     QApplication app(argc, argv);
+    QCoreApplication::setApplicationName("Settings Editor");
+    QCoreApplication::setApplicationVersion(QT_VERSION_STR);
+
     MainWindow mainWin;
     mainWin.show();
     return app.exec();
diff --git a/examples/widgets/tools/settingseditor/mainwindow.cpp b/examples/widgets/tools/settingseditor/mainwindow.cpp
index 078a84576d..dbc8309eef 100644
--- a/examples/widgets/tools/settingseditor/mainwindow.cpp
+++ b/examples/widgets/tools/settingseditor/mainwindow.cpp
@@ -45,20 +45,20 @@
 #include "settingstree.h"
 
 MainWindow::MainWindow()
+    : settingsTree(new SettingsTree)
+    , locationDialog(Q_NULLPTR)
 {
-    settingsTree = new SettingsTree;
     setCentralWidget(settingsTree);
 
-    locationDialog = 0;
-
     createActions();
-    createMenus();
 
     autoRefreshAct->setChecked(true);
     fallbacksAct->setChecked(true);
 
-    setWindowTitle(tr("Settings Editor"));
-    resize(500, 600);
+    setWindowTitle(QCoreApplication::applicationName());
+    const QRect availableGeometry = QApplication::desktop()->availableGeometry(this);
+    adjustSize();
+    move((availableGeometry.width() - width()) / 2, (availableGeometry.height() - height()) / 2);
 }
 
 void MainWindow::openSettings()
@@ -66,49 +66,60 @@ void MainWindow::openSettings()
     if (!locationDialog)
         locationDialog = new LocationDialog(this);
 
-    if (locationDialog->exec()) {
-        QSettings *settings = new QSettings(locationDialog->format(),
-                                            locationDialog->scope(),
-                                            locationDialog->organization(),
-                                            locationDialog->application());
-        setSettingsObject(settings);
-        fallbacksAct->setEnabled(true);
-    }
+    if (locationDialog->exec() != QDialog::Accepted)
+        return;
+
+    SettingsPtr settings(new QSettings(locationDialog->format(),
+                                       locationDialog->scope(),
+                                       locationDialog->organization(),
+                                       locationDialog->application()));
+
+    setSettingsObject(settings);
+    fallbacksAct->setEnabled(true);
 }
 
 void MainWindow::openIniFile()
 {
-    QString fileName = QFileDialog::getOpenFileName(this, tr("Open INI File"),
-                               "", tr("INI Files (*.ini *.conf)"));
-    if (!fileName.isEmpty()) {
-        QSettings *settings = new QSettings(fileName, QSettings::IniFormat);
-        setSettingsObject(settings);
-        fallbacksAct->setEnabled(false);
-    }
+    const QString directory = QStandardPaths::writableLocation(QStandardPaths::ConfigLocation);
+    const QString fileName =
+        QFileDialog::getOpenFileName(this, tr("Open INI File"),
+                                     directory, tr("INI Files (*.ini *.conf)"));
+    if (fileName.isEmpty())
+        return;
+
+    SettingsPtr settings(new QSettings(fileName, QSettings::IniFormat));
+
+    setSettingsObject(settings);
+    fallbacksAct->setEnabled(false);
 }
 
 void MainWindow::openPropertyList()
 {
-    QString fileName = QFileDialog::getOpenFileName(this,
-                               tr("Open Property List"),
-                               "", tr("Property List Files (*.plist)"));
-    if (!fileName.isEmpty()) {
-        QSettings *settings = new QSettings(fileName, QSettings::NativeFormat);
-        setSettingsObject(settings);
-        fallbacksAct->setEnabled(false);
-    }
+    const QString directory = QStandardPaths::writableLocation(QStandardPaths::ConfigLocation);
+    const QString fileName =
+        QFileDialog::getOpenFileName(this, tr("Open Property List"),
+                                     directory, tr("Property List Files (*.plist)"));
+    if (fileName.isEmpty())
+        return;
+
+    SettingsPtr settings(new QSettings(fileName, QSettings::NativeFormat));
+    setSettingsObject(settings);
+    fallbacksAct->setEnabled(false);
 }
 
 void MainWindow::openRegistryPath()
 {
-    QString path = QInputDialog::getText(this, tr("Open Registry Path"),
-                           tr("Enter the path in the Windows registry:"),
-                           QLineEdit::Normal, "HKEY_CURRENT_USER\\");
-    if (!path.isEmpty()) {
-        QSettings *settings = new QSettings(path, QSettings::NativeFormat);
-        setSettingsObject(settings);
-        fallbacksAct->setEnabled(false);
-    }
+    const QString path =
+        QInputDialog::getText(this, tr("Open Registry Path"),
+                              tr("Enter the path in the Windows registry:"),
+                              QLineEdit::Normal, "HKEY_CURRENT_USER\\");
+    if (path.isEmpty())
+        return;
+
+    SettingsPtr settings(new QSettings(path, QSettings::NativeFormat));
+
+    setSettingsObject(settings);
+    fallbacksAct->setEnabled(false);
 }
 
 void MainWindow::about()
@@ -120,88 +131,59 @@ void MainWindow::about()
 
 void MainWindow::createActions()
 {
-    openSettingsAct = new QAction(tr("&Open Application Settings..."), this);
+    QMenu *fileMenu = menuBar()->addMenu(tr("&File"));
+
+    QAction *openSettingsAct = fileMenu->addAction(tr("&Open Application Settings..."), this, &MainWindow::openSettings);
     openSettingsAct->setShortcuts(QKeySequence::Open);
-    connect(openSettingsAct, SIGNAL(triggered()), this, SLOT(openSettings()));
 
-    openIniFileAct = new QAction(tr("Open I&NI File..."), this);
+    QAction *openIniFileAct = fileMenu->addAction(tr("Open I&NI File..."), this, &MainWindow::openIniFile);
     openIniFileAct->setShortcut(tr("Ctrl+N"));
-    connect(openIniFileAct, SIGNAL(triggered()), this, SLOT(openIniFile()));
 
-    openPropertyListAct = new QAction(tr("Open Mac &Property List..."), this);
+#ifdef Q_OS_OSX
+    QAction *openPropertyListAct = fileMenu->addAction(tr("Open Apple &Property List..."), this, &MainWindow::openPropertyList);
     openPropertyListAct->setShortcut(tr("Ctrl+P"));
-    connect(openPropertyListAct, SIGNAL(triggered()),
-            this, SLOT(openPropertyList()));
+#endif // Q_OS_OSX
 
-    openRegistryPathAct = new QAction(tr("Open Windows &Registry Path..."),
-                                      this);
+#ifdef Q_OS_WIN
+    QAction *openRegistryPathAct = fileMenu->addAction(tr("Open Windows &Registry Path..."), this, &MainWindow::openRegistryPath);
     openRegistryPathAct->setShortcut(tr("Ctrl+G"));
-    connect(openRegistryPathAct, SIGNAL(triggered()),
-            this, SLOT(openRegistryPath()));
+#endif // Q_OS_WIN
+
+    fileMenu->addSeparator();
 
-    refreshAct = new QAction(tr("&Refresh"), this);
+    refreshAct = fileMenu->addAction(tr("&Refresh"), settingsTree, &SettingsTree::refresh);
     refreshAct->setShortcut(tr("Ctrl+R"));
     refreshAct->setEnabled(false);
-    connect(refreshAct, SIGNAL(triggered()), settingsTree, SLOT(refresh()));
 
-    exitAct = new QAction(tr("E&xit"), this);
+    fileMenu->addSeparator();
+
+    QAction *exitAct = fileMenu->addAction(tr("E&xit"), this, &QWidget::close);
     exitAct->setShortcuts(QKeySequence::Quit);
-    connect(exitAct, SIGNAL(triggered()), this, SLOT(close()));
 
-    autoRefreshAct = new QAction(tr("&Auto-Refresh"), this);
+    QMenu *optionsMenu = menuBar()->addMenu(tr("&Options"));
+
+    autoRefreshAct = optionsMenu->addAction(tr("&Auto-Refresh"));
     autoRefreshAct->setShortcut(tr("Ctrl+A"));
     autoRefreshAct->setCheckable(true);
     autoRefreshAct->setEnabled(false);
-    connect(autoRefreshAct, SIGNAL(triggered(bool)),
-            settingsTree, SLOT(setAutoRefresh(bool)));
-    connect(autoRefreshAct, SIGNAL(triggered(bool)),
-            refreshAct, SLOT(setDisabled(bool)));
+    connect(autoRefreshAct, &QAction::triggered,
+            settingsTree, &SettingsTree::setAutoRefresh);
+    connect(autoRefreshAct, &QAction::triggered,
+            refreshAct, &QAction::setDisabled);
 
-    fallbacksAct = new QAction(tr("&Fallbacks"), this);
+    fallbacksAct = optionsMenu->addAction(tr("&Fallbacks"));
     fallbacksAct->setShortcut(tr("Ctrl+F"));
     fallbacksAct->setCheckable(true);
     fallbacksAct->setEnabled(false);
-    connect(fallbacksAct, SIGNAL(triggered(bool)),
-            settingsTree, SLOT(setFallbacksEnabled(bool)));
-
-    aboutAct = new QAction(tr("&About"), this);
-    connect(aboutAct, SIGNAL(triggered()), this, SLOT(about()));
-
-    aboutQtAct = new QAction(tr("About &Qt"), this);
-    connect(aboutQtAct, SIGNAL(triggered()), qApp, SLOT(aboutQt()));
-
-#ifndef Q_OS_MAC
-    openPropertyListAct->setEnabled(false);
-#endif
-#ifndef Q_OS_WIN
-    openRegistryPathAct->setEnabled(false);
-#endif
-}
-
-void MainWindow::createMenus()
-{
-    fileMenu = menuBar()->addMenu(tr("&File"));
-    fileMenu->addAction(openSettingsAct);
-    fileMenu->addAction(openIniFileAct);
-    fileMenu->addAction(openPropertyListAct);
-    fileMenu->addAction(openRegistryPathAct);
-    fileMenu->addSeparator();
-    fileMenu->addAction(refreshAct);
-    fileMenu->addSeparator();
-    fileMenu->addAction(exitAct);
-
-    optionsMenu = menuBar()->addMenu(tr("&Options"));
-    optionsMenu->addAction(autoRefreshAct);
-    optionsMenu->addAction(fallbacksAct);
-
-    menuBar()->addSeparator();
+    connect(fallbacksAct, &QAction::triggered,
+            settingsTree, &SettingsTree::setFallbacksEnabled);
 
-    helpMenu = menuBar()->addMenu(tr("&Help"));
-    helpMenu->addAction(aboutAct);
-    helpMenu->addAction(aboutQtAct);
+    QMenu *helpMenu = menuBar()->addMenu(tr("&Help"));
+    helpMenu->addAction(tr("&About"), this, &MainWindow::about);
+    helpMenu->addAction(tr("About &Qt"), qApp, &QCoreApplication::quit);
 }
 
-void MainWindow::setSettingsObject(QSettings *settings)
+void MainWindow::setSettingsObject(const SettingsPtr &settings)
 {
     settings->setFallbacksEnabled(fallbacksAct->isChecked());
     settingsTree->setSettingsObject(settings);
@@ -209,14 +191,14 @@ void MainWindow::setSettingsObject(QSettings *settings)
     refreshAct->setEnabled(true);
     autoRefreshAct->setEnabled(true);
 
-    QString niceName = settings->fileName();
-    niceName.replace("\\", "/");
-    int pos = niceName.lastIndexOf("/");
+    QString niceName = QDir::cleanPath(settings->fileName());
+    int pos = niceName.lastIndexOf(QLatin1Char('/'));
     if (pos != -1)
         niceName.remove(0, pos + 1);
 
     if (!settings->isWritable())
         niceName = tr("%1 (read only)").arg(niceName);
 
-    setWindowTitle(tr("%1 - %2").arg(niceName).arg(tr("Settings Editor")));
+    setWindowTitle(tr("%1 - %2").arg(niceName, QCoreApplication::applicationName()));
+    statusBar()->showMessage(tr("Opened \"%1\"").arg(QDir::toNativeSeparators(settings->fileName())));
 }
diff --git a/examples/widgets/tools/settingseditor/mainwindow.h b/examples/widgets/tools/settingseditor/mainwindow.h
index 55180c3771..4b1a28dfba 100644
--- a/examples/widgets/tools/settingseditor/mainwindow.h
+++ b/examples/widgets/tools/settingseditor/mainwindow.h
@@ -42,10 +42,10 @@
 #define MAINWINDOW_H
 
 #include <QMainWindow>
+#include <QSharedPointer>
 
 QT_BEGIN_NAMESPACE
 class QAction;
-class QMenu;
 class QSettings;
 QT_END_NAMESPACE
 class LocationDialog;
@@ -56,6 +56,8 @@ class MainWindow : public QMainWindow
     Q_OBJECT
 
 public:
+    typedef QSharedPointer<QSettings> SettingsPtr;
+
     MainWindow();
 
 private slots:
@@ -67,25 +69,13 @@ private slots:
 
 private:
     void createActions();
-    void createMenus();
-    void setSettingsObject(QSettings *settings);
+    void setSettingsObject(const SettingsPtr &settings);
 
     SettingsTree *settingsTree;
     LocationDialog *locationDialog;
-
-    QMenu *fileMenu;
-    QMenu *optionsMenu;
-    QMenu *helpMenu;
-    QAction *openSettingsAct;
-    QAction *openIniFileAct;
-    QAction *openPropertyListAct;
-    QAction *openRegistryPathAct;
     QAction *refreshAct;
-    QAction *exitAct;
     QAction *autoRefreshAct;
     QAction *fallbacksAct;
-    QAction *aboutAct;
-    QAction *aboutQtAct;
 };
 
 #endif
diff --git a/examples/widgets/tools/settingseditor/settingstree.cpp b/examples/widgets/tools/settingseditor/settingstree.cpp
index d9d53968ef..b75e3bdc54 100644
--- a/examples/widgets/tools/settingseditor/settingstree.cpp
+++ b/examples/widgets/tools/settingseditor/settingstree.cpp
@@ -45,18 +45,18 @@
 
 SettingsTree::SettingsTree(QWidget *parent)
     : QTreeWidget(parent)
+    , autoRefresh(false)
 {
     setItemDelegate(new VariantDelegate(this));
 
     QStringList labels;
     labels << tr("Setting") << tr("Type") << tr("Value");
     setHeaderLabels(labels);
-    header()->setSectionResizeMode(0, QHeaderView::Stretch);
+    header()->setSectionResizeMode(0, QHeaderView::ResizeToContents);
+    header()->setSectionResizeMode(1, QHeaderView::ResizeToContents);
     header()->setSectionResizeMode(2, QHeaderView::Stretch);
 
-    settings = 0;
     refreshTimer.setInterval(2000);
-    autoRefresh = false;
 
     groupIcon.addPixmap(style()->standardPixmap(QStyle::SP_DirClosedIcon),
                         QIcon::Normal, QIcon::Off);
@@ -64,34 +64,37 @@ SettingsTree::SettingsTree(QWidget *parent)
                         QIcon::Normal, QIcon::On);
     keyIcon.addPixmap(style()->standardPixmap(QStyle::SP_FileIcon));
 
-    connect(&refreshTimer, SIGNAL(timeout()), this, SLOT(maybeRefresh()));
+    connect(&refreshTimer, &QTimer::timeout, this, &SettingsTree::maybeRefresh);
 }
 
-void SettingsTree::setSettingsObject(QSettings *settings)
+SettingsTree::~SettingsTree()
 {
-    delete this->settings;
-    this->settings = settings;
+}
+
+void SettingsTree::setSettingsObject(const SettingsPtr &newSettings)
+{
+    settings = newSettings;
     clear();
 
-    if (settings) {
-        settings->setParent(this);
+    if (settings.isNull()) {
+        refreshTimer.stop();
+    } else {
         refresh();
         if (autoRefresh)
             refreshTimer.start();
-    } else {
-        refreshTimer.stop();
     }
 }
 
 QSize SettingsTree::sizeHint() const
 {
-    return QSize(800, 600);
+    const QRect availableGeometry = QApplication::desktop()->availableGeometry(this);
+    return QSize(availableGeometry.width() * 2 / 3, availableGeometry.height() * 2 / 3);
 }
 
 void SettingsTree::setAutoRefresh(bool autoRefresh)
 {
     this->autoRefresh = autoRefresh;
-    if (settings) {
+    if (!settings.isNull()) {
         if (autoRefresh) {
             maybeRefresh();
             refreshTimer.start();
@@ -103,7 +106,7 @@ void SettingsTree::setAutoRefresh(bool autoRefresh)
 
 void SettingsTree::setFallbacksEnabled(bool enabled)
 {
-    if (settings) {
+    if (!settings.isNull()) {
         settings->setFallbacksEnabled(enabled);
         refresh();
     }
@@ -117,17 +120,17 @@ void SettingsTree::maybeRefresh()
 
 void SettingsTree::refresh()
 {
-    if (!settings)
+    if (settings.isNull())
         return;
 
-    disconnect(this, SIGNAL(itemChanged(QTreeWidgetItem*,int)),
-               this, SLOT(updateSetting(QTreeWidgetItem*)));
+    disconnect(this, &QTreeWidget::itemChanged,
+               this, &SettingsTree::updateSetting);
 
     settings->sync();
     updateChildItems(0);
 
-    connect(this, SIGNAL(itemChanged(QTreeWidgetItem*,int)),
-            this, SLOT(updateSetting(QTreeWidgetItem*)));
+    connect(this, &QTreeWidget::itemChanged,
+            this, &SettingsTree::updateSetting);
 }
 
 bool SettingsTree::event(QEvent *event)
@@ -144,7 +147,7 @@ void SettingsTree::updateSetting(QTreeWidgetItem *item)
     QString key = item->text(0);
     QTreeWidgetItem *ancestor = item->parent();
     while (ancestor) {
-        key.prepend(ancestor->text(0) + "/");
+        key.prepend(ancestor->text(0) + QLatin1Char('/'));
         ancestor = ancestor->parent();
     }
 
@@ -162,8 +165,8 @@ void SettingsTree::updateChildItems(QTreeWidgetItem *parent)
         int childIndex = findChild(parent, group, dividerIndex);
         if (childIndex != -1) {
             child = childAt(parent, childIndex);
-            child->setText(1, "");
-            child->setText(2, "");
+            child->setText(1, QString());
+            child->setText(2, QString());
             child->setData(2, Qt::UserRole, QVariant());
             moveItemForward(parent, childIndex, dividerIndex);
         } else {
@@ -177,7 +180,7 @@ void SettingsTree::updateChildItems(QTreeWidgetItem *parent)
         settings->endGroup();
     }
 
-    foreach (QString key, settings->childKeys()) {
+    foreach (const QString &key, settings->childKeys()) {
         QTreeWidgetItem *child;
         int childIndex = findChild(parent, key, 0);
 
diff --git a/examples/widgets/tools/settingseditor/settingstree.h b/examples/widgets/tools/settingseditor/settingstree.h
index 2a64a5a496..4f542d2543 100644
--- a/examples/widgets/tools/settingseditor/settingstree.h
+++ b/examples/widgets/tools/settingseditor/settingstree.h
@@ -44,6 +44,7 @@
 #include <QIcon>
 #include <QTimer>
 #include <QTreeWidget>
+#include <QSharedPointer>
 
 QT_BEGIN_NAMESPACE
 class QSettings;
@@ -54,9 +55,12 @@ class SettingsTree : public QTreeWidget
     Q_OBJECT
 
 public:
+    typedef QSharedPointer<QSettings> SettingsPtr;
+
     SettingsTree(QWidget *parent = 0);
+    ~SettingsTree();
 
-    void setSettingsObject(QSettings *settings);
+    void setSettingsObject(const SettingsPtr &settings);
     QSize sizeHint() const Q_DECL_OVERRIDE;
 
 public slots:
@@ -80,7 +84,7 @@ private:
     int findChild(QTreeWidgetItem *parent, const QString &text, int startIndex);
     void moveItemForward(QTreeWidgetItem *parent, int oldIndex, int newIndex);
 
-    QSettings *settings;
+    SettingsPtr settings;
     QTimer refreshTimer;
     bool autoRefresh;
     QIcon groupIcon;