QtSupport: Simplify welcome page examples model handling further

Use the ExampleSetModel directly in the combobox, rely on normal
model reset behavior behavior for gui updates.

Change-Id: Icdb34ff0f572caaf92259530823e90bfd783b933
Task-number: QTCREATORBUG-17678
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/qtsupport/exampleslistmodel.cpp

@@ -33,11 +33,13 @@
 
 #include <coreplugin/helpmanager.h>
 #include <coreplugin/icore.h>
+
 #include <qtsupport/qtkitinformation.h>
 #include <qtsupport/qtversionmanager.h>
+
+#include <utils/algorithm.h>
 #include <utils/environment.h>
 #include <utils/qtcassert.h>
-#include <utils/algorithm.h>
 
 #include <algorithm>
 
@@ -68,22 +70,54 @@ int ExampleSetModel::readCurrentIndexFromSettings() const
     return -1;
 }
 
-ExampleSetModel::ExampleSetModel(ExamplesListModel *examplesModel, QObject *parent) :
+ExampleSetModel::ExampleSetModel()
-    QStandardItemModel(parent),
-    examplesModel(examplesModel)
 {
+    // read extra example sets settings
+    QSettings *settings = Core::ICore::settings();
+    const QStringList list = settings->value("Help/InstalledExamples", QStringList()).toStringList();
+    if (debugExamples())
+        qWarning() << "Reading Help/InstalledExamples from settings:" << list;
+    for (const QString &item : list) {
+        const QStringList &parts = item.split(QLatin1Char('|'));
+        if (parts.size() < 3) {
+            if (debugExamples())
+                qWarning() << "Item" << item << "has less than 3 parts (separated by '|'):" << parts;
+            continue;
+        }
+        ExtraExampleSet set;
+        set.displayName = parts.at(0);
+        set.manifestPath = parts.at(1);
+        set.examplesPath = parts.at(2);
+        QFileInfo fi(set.manifestPath);
+        if (!fi.isDir() || !fi.isReadable()) {
+            if (debugExamples())
+                qWarning() << "Manifest path " << set.manifestPath << "is not a readable directory, ignoring";
+            continue;
+        }
+        m_extraExampleSets.append(set);
+        if (debugExamples()) {
+            qWarning() << "Adding examples set displayName=" << set.displayName
+                       << ", manifestPath=" << set.manifestPath
+                       << ", examplesPath=" << set.examplesPath;
+        }
     }
 
-void ExampleSetModel::update()
+    connect(QtVersionManager::instance(), &QtVersionManager::qtVersionsLoaded,
+            this, &ExampleSetModel::qtVersionManagerLoaded);
+    connect(Core::HelpManager::instance(), &Core::HelpManager::setupFinished,
+            this, &ExampleSetModel::helpManagerInitialized);
+}
+
+void ExampleSetModel::recreateModel()
 {
     beginResetModel();
     clear();
 
     QSet<QString> extraManifestDirs;
-    QList<ExamplesListModel::ExtraExampleSet> extraExampleSets = examplesModel->extraExampleSets();
+    for (int i = 0; i < m_extraExampleSets.size(); ++i)  {
-    for (int i = 0; i < extraExampleSets.size(); ++i)  {
+        const ExtraExampleSet &set = m_extraExampleSets.at(i);
-        ExamplesListModel::ExtraExampleSet set = extraExampleSets.at(i);
         QStandardItem *newItem = new QStandardItem();
+        newItem->setData(set.displayName, Qt::DisplayRole);
         newItem->setData(set.displayName, Qt::UserRole + 1);
         newItem->setData(QVariant(), Qt::UserRole + 2);
         newItem->setData(i, Qt::UserRole + 3);
@@ -102,6 +136,7 @@ void ExampleSetModel::update()
             continue;
         }
         QStandardItem *newItem = new QStandardItem();
+        newItem->setData(version->displayName(), Qt::DisplayRole);
         newItem->setData(version->displayName(), Qt::UserRole + 1);
         newItem->setData(version->uniqueId(), Qt::UserRole + 2);
         newItem->setData(QVariant(), Qt::UserRole + 3);
@@ -122,13 +157,12 @@ int ExampleSetModel::indexForQtVersion(BaseQtVersion *qtVersion) const
         if (getType(i) == QtExampleSet && getQtId(i) == qtVersion->uniqueId())
             return i;
     }
+
     // check for extra set
-    const QList<ExamplesListModel::ExtraExampleSet> &extraExamples
-            = examplesModel->extraExampleSets();
     const QString &documentationPath = qtVersion->documentationPath();
     for (int i = 0; i < rowCount(); ++i) {
-        if (getType(i) == ExtraExampleSet
+        if (getType(i) == ExtraExampleSetType
-                && extraExamples.at(getExtraExampleSetIndex(i)).manifestPath == documentationPath)
+                && m_extraExampleSets.at(getExtraExampleSetIndex(i)).manifestPath == documentationPath)
             return i;
     }
     return -1;
@@ -161,7 +195,7 @@ ExampleSetModel::ExampleSetType ExampleSetModel::getType(int i) const
     QVariant variant = data(modelIndex, Qt::UserRole + 2); /*Qt version uniqueId*/
     if (variant.isValid())
         return QtExampleSet;
-    return ExtraExampleSet;
+    return ExtraExampleSetType;
 }
 
 int ExampleSetModel::getQtId(int i) const
@@ -184,40 +218,11 @@ int ExampleSetModel::getExtraExampleSetIndex(int i) const
     return variant.toInt();
 }
 
-ExamplesListModel::ExamplesListModel(QObject *parent) :
+ExamplesListModel::ExamplesListModel(QObject *parent)
-    QAbstractListModel(parent),
+    : QAbstractListModel(parent)
-    m_exampleSetModel(new ExampleSetModel(this, this))
 {
-    // read extra example sets settings
+    connect(&m_exampleSetModel, &ExampleSetModel::selectedExampleSetChanged,
-    QSettings *settings = Core::ICore::settings();
+            this, &ExamplesListModel::updateExamples);
-    QStringList list = settings->value(QLatin1String("Help/InstalledExamples"),
-                                       QStringList()).toStringList();
-    if (debugExamples())
-        qWarning() << "Reading Help/InstalledExamples from settings:" << list;
-    foreach (const QString &item, list) {
-        const QStringList &parts = item.split(QLatin1Char('|'));
-        if (parts.size() < 3) {
-            if (debugExamples())
-                qWarning() << "Item" << item << "has less than 3 parts (separated by '|'):" << parts;
-            continue;
-        }
-        ExtraExampleSet set;
-        set.displayName = parts.at(0);
-        set.manifestPath = parts.at(1);
-        set.examplesPath = parts.at(2);
-        QFileInfo fi(set.manifestPath);
-        if (!fi.isDir() || !fi.isReadable()) {
-            if (debugExamples())
-                qWarning() << "Manifest path " << set.manifestPath << "is not a readable directory, ignoring";
-            continue;
-        }
-        m_extraExampleSets.append(set);
-        if (debugExamples()) {
-            qWarning() << "Adding examples set displayName=" << set.displayName
-                       << ", manifestPath=" << set.manifestPath
-                       << ", examplesPath=" << set.examplesPath;
-        }
-    }
 }
 
 static QString fixStringForTags(const QString &string)
@@ -431,7 +436,7 @@ void ExamplesListModel::updateExamples()
     QString examplesInstallPath;
     QString demosInstallPath;
 
-    QStringList sources = exampleSources(&examplesInstallPath, &demosInstallPath);
+    QStringList sources = m_exampleSetModel.exampleSources(&examplesInstallPath, &demosInstallPath);
 
     beginResetModel();
     m_exampleItems.clear();
@@ -472,7 +477,7 @@ void ExamplesListModel::updateExamples()
     endResetModel();
 }
 
-void ExamplesListModel::updateQtVersions()
+void ExampleSetModel::updateQtVersionList()
 {
     QList<BaseQtVersion*> versions
             = QtVersionManager::sortVersions(
@@ -486,35 +491,34 @@ void ExamplesListModel::updateQtVersions()
     if (defaultVersion && versions.contains(defaultVersion))
         versions.move(versions.indexOf(defaultVersion), 0);
 
-    m_exampleSetModel->update();
+    recreateModel();
 
     int currentIndex = m_selectedExampleSetIndex;
     if (currentIndex < 0) // reset from settings
-        currentIndex = m_exampleSetModel->readCurrentIndexFromSettings();
+        currentIndex = readCurrentIndexFromSettings();
 
-    ExampleSetModel::ExampleSetType currentType
+    ExampleSetModel::ExampleSetType currentType = getType(currentIndex);
-            = m_exampleSetModel->getType(currentIndex);
 
     if (currentType == ExampleSetModel::InvalidExampleSet) {
         // select examples corresponding to 'highest' Qt version
         BaseQtVersion *highestQt = findHighestQtVersion();
-        currentIndex = m_exampleSetModel->indexForQtVersion(highestQt);
+        currentIndex = indexForQtVersion(highestQt);
     } else if (currentType == ExampleSetModel::QtExampleSet) {
         // try to select the previously selected Qt version, or
         // select examples corresponding to 'highest' Qt version
-        int currentQtId = m_exampleSetModel->getQtId(currentIndex);
+        int currentQtId = getQtId(currentIndex);
         BaseQtVersion *newQtVersion = QtVersionManager::version(currentQtId);
         if (!newQtVersion)
             newQtVersion = findHighestQtVersion();
-        currentIndex = m_exampleSetModel->indexForQtVersion(newQtVersion);
+        currentIndex = indexForQtVersion(newQtVersion);
     } // nothing to do for extra example sets
     selectExampleSet(currentIndex);
+    emit selectedExampleSetChanged(currentIndex);
 }
 
-BaseQtVersion *ExamplesListModel::findHighestQtVersion() const
+BaseQtVersion *ExampleSetModel::findHighestQtVersion() const
 {
     BaseQtVersion *newVersion = nullptr;
-
     const QList<BaseQtVersion *> versions = QtVersionManager::versions();
     for (BaseQtVersion *version : versions) {
         if (!newVersion) {
@@ -535,7 +539,7 @@ BaseQtVersion *ExamplesListModel::findHighestQtVersion() const
     return newVersion;
 }
 
-QStringList ExamplesListModel::exampleSources(QString *examplesInstallPath, QString *demosInstallPath)
+QStringList ExampleSetModel::exampleSources(QString *examplesInstallPath, QString *demosInstallPath)
 {
     QStringList sources;
 
@@ -546,16 +550,15 @@ QStringList ExamplesListModel::exampleSources(QString *examplesInstallPath, QStr
     QString demosPath;
     QString manifestScanPath;
 
-    ExampleSetModel::ExampleSetType currentType
+    ExampleSetModel::ExampleSetType currentType = getType(m_selectedExampleSetIndex);
-            = m_exampleSetModel->getType(m_selectedExampleSetIndex);
+    if (currentType == ExampleSetModel::ExtraExampleSetType) {
-    if (currentType == ExampleSetModel::ExtraExampleSet) {
+        int index = getExtraExampleSetIndex(m_selectedExampleSetIndex);
-        int index = m_exampleSetModel->getExtraExampleSetIndex(m_selectedExampleSetIndex);
         ExtraExampleSet exampleSet = m_extraExampleSets.at(index);
         manifestScanPath = exampleSet.manifestPath;
         examplesPath = exampleSet.examplesPath;
         demosPath = exampleSet.examplesPath;
     } else if (currentType == ExampleSetModel::QtExampleSet) {
-        int qtId = m_exampleSetModel->getQtId(m_selectedExampleSetIndex);
+        int qtId = getQtId(m_selectedExampleSetIndex);
         foreach (BaseQtVersion *version, QtVersionManager::versions()) {
             if (version->uniqueId() == qtId) {
                 manifestScanPath = version->documentationPath();
@@ -615,67 +618,54 @@ QVariant ExamplesListModel::data(const QModelIndex &index, int role) const
     }
 }
 
-void ExamplesListModel::update()
+void ExampleSetModel::selectExampleSet(int index)
-{
-    updateQtVersions();
-    updateExamples();
-}
-
-int ExamplesListModel::selectedExampleSet() const
-{
-    return m_selectedExampleSetIndex;
-}
-
-void ExamplesListModel::selectExampleSet(int index)
 {
     if (index != m_selectedExampleSetIndex) {
         m_selectedExampleSetIndex = index;
-        m_exampleSetModel->writeCurrentIdToSettings(m_selectedExampleSetIndex);
+        writeCurrentIdToSettings(m_selectedExampleSetIndex);
-        updateExamples();
         emit selectedExampleSetChanged(m_selectedExampleSetIndex);
     }
 }
 
-QStringList ExamplesListModel::exampleSets() const
+void ExampleSetModel::qtVersionManagerLoaded()
 {
-    return Utils::transform(QtVersionManager::versions(), &BaseQtVersion::displayName);
+    m_qtVersionManagerInitialized = true;
+    tryToInitialize();
 }
 
+void ExampleSetModel::helpManagerInitialized()
+{
+    m_helpManagerInitialized = true;
+    tryToInitialize();
+}
+
+
+void ExampleSetModel::tryToInitialize()
+{
+    if (m_initalized || !m_qtVersionManagerInitialized || !m_helpManagerInitialized)
+        return;
+
+    m_initalized = true;
+
+    connect(QtVersionManager::instance(), &QtVersionManager::qtVersionsChanged,
+            this, &ExampleSetModel::updateQtVersionList);
+    connect(ProjectExplorer::KitManager::instance(), &ProjectExplorer::KitManager::defaultkitChanged,
+            this, &ExampleSetModel::updateQtVersionList);
+
+    updateQtVersionList();
+}
+
+
 ExamplesListModelFilter::ExamplesListModelFilter(ExamplesListModel *sourceModel, bool showTutorialsOnly, QObject *parent) :
     QSortFilterProxyModel(parent),
-    m_showTutorialsOnly(showTutorialsOnly),
+    m_showTutorialsOnly(showTutorialsOnly)
-    m_sourceModel(sourceModel)
 {
-    // initialization hooks
+    setSourceModel(sourceModel);
-    connect(QtVersionManager::instance(), &QtVersionManager::qtVersionsLoaded,
-            this, &ExamplesListModelFilter::qtVersionManagerLoaded);
-    connect(Core::HelpManager::instance(), &Core::HelpManager::setupFinished,
-            this, &ExamplesListModelFilter::helpManagerInitialized);
-
-    setSourceModel(m_sourceModel);
     setDynamicSortFilter(true);
     setFilterCaseSensitivity(Qt::CaseInsensitive);
     sort(0);
 }
 
-void ExamplesListModelFilter::updateFilter()
-{
-    ExamplesListModel *exampleListModel = qobject_cast<ExamplesListModel*>(sourceModel());
-    if (exampleListModel) {
-        exampleListModel->beginReset();
-        invalidateFilter();
-        exampleListModel->endReset();
-    }
-}
-
-void ExamplesListModelFilter::setFilterStrings(const QStringList &arg)
-{
-    if (m_filterStrings != arg) {
-        m_filterStrings = arg;
-        delayedUpdateFilter();
-    }
-}
-
 bool ExamplesListModelFilter::filterAcceptsRow(int sourceRow, const QModelIndex &sourceParent) const
 {
     const ExampleItem item = sourceModel()->index(sourceRow, 0, sourceParent).data(Qt::UserRole).value<ExampleItem>();
@@ -711,63 +701,6 @@ bool ExamplesListModelFilter::filterAcceptsRow(int sourceRow, const QModelIndex
     return QSortFilterProxyModel::filterAcceptsRow(sourceRow, sourceParent);
 }
 
-int ExamplesListModelFilter::rowCount(const QModelIndex &parent) const
-{
-    exampleDataRequested();
-    return QSortFilterProxyModel::rowCount(parent);
-}
-
-QVariant ExamplesListModelFilter::data(const QModelIndex &index, int role) const
-{
-    exampleDataRequested();
-    return QSortFilterProxyModel::data(index, role);
-}
-
-void ExamplesListModelFilter::setFilterTags(const QStringList &arg)
-{
-    if (m_filterTags != arg) {
-        m_filterTags = arg;
-        emit filterTagsChanged(arg);
-    }
-}
-
-void ExamplesListModelFilter::handleQtVersionsChanged()
-{
-    m_sourceModel->update();
-}
-
-void ExamplesListModelFilter::qtVersionManagerLoaded()
-{
-    m_qtVersionManagerInitialized = true;
-    tryToInitialize();
-}
-
-void ExamplesListModelFilter::helpManagerInitialized()
-{
-    m_helpManagerInitialized = true;
-    tryToInitialize();
-}
-
-void ExamplesListModelFilter::exampleDataRequested() const
-{
-    ExamplesListModelFilter *that = const_cast<ExamplesListModelFilter *>(this);
-    that->m_exampleDataRequested = true;
-    that->tryToInitialize();
-}
-
-void ExamplesListModelFilter::tryToInitialize()
-{
-    if (!m_initalized
-            && m_qtVersionManagerInitialized && m_helpManagerInitialized && m_exampleDataRequested) {
-        m_initalized = true;
-        connect(QtVersionManager::instance(), &QtVersionManager::qtVersionsChanged,
-                this, &ExamplesListModelFilter::handleQtVersionsChanged);
-        connect(ProjectExplorer::KitManager::instance(), &ProjectExplorer::KitManager::defaultkitChanged,
-                this, &ExamplesListModelFilter::handleQtVersionsChanged);
-        handleQtVersionsChanged();
-    }
-}
-
 void ExamplesListModelFilter::delayedUpdateFilter()
 {
     if (m_timerId != 0)
@@ -779,7 +712,7 @@ void ExamplesListModelFilter::delayedUpdateFilter()
 void ExamplesListModelFilter::timerEvent(QTimerEvent *timerEvent)
 {
     if (m_timerId == timerEvent->timerId()) {
-        updateFilter();
+        invalidateFilter();
         killTimer(m_timerId);
         m_timerId = 0;
     }
@@ -871,32 +804,31 @@ void ExamplesListModelFilter::setSearchString(const QString &arg)
 {
     if (m_searchString == arg)
         return;
+
     m_searchString = arg;
-    emit searchStringChanged(m_searchString);
+    m_filterTags.clear();
+    m_filterStrings.clear();
+
     // parse and update
-    QStringList tags;
-    QStringList searchTerms;
     SearchStringLexer lex(arg);
     bool isTag = false;
     while (int tk = lex()) {
         if (tk == SearchStringLexer::TAG) {
             isTag = true;
-            searchTerms.append(lex.yytext);
+            m_filterStrings.append(lex.yytext);
         }
 
         if (tk == SearchStringLexer::STRING_LITERAL) {
             if (isTag) {
-                searchTerms.pop_back();
+                m_filterStrings.pop_back();
-                tags.append(lex.yytext);
+                m_filterTags.append(lex.yytext);
                 isTag = false;
             } else {
-                searchTerms.append(lex.yytext);
+                m_filterStrings.append(lex.yytext);
             }
         }
     }
 
-    setFilterStrings(searchTerms);
-    setFilterTags(tags);
     delayedUpdateFilter();
 }
 

src/plugins/qtsupport/exampleslistmodel.h

@@ -25,12 +25,13 @@
 
 #pragma once
 
+#include <qtsupport/baseqtversion.h>
+
 #include <QAbstractListModel>
 #include <QSortFilterProxyModel>
 #include <QStandardItemModel>
 #include <QStringList>
 #include <QXmlStreamReader>
-#include <qtsupport/baseqtversion.h>
 
 namespace QtSupport {
 namespace Internal {
@@ -42,28 +43,54 @@ class ExampleSetModel : public QStandardItemModel
     Q_OBJECT
 
 public:
+    ExampleSetModel();
+
+    int selectedExampleSet() const { return m_selectedExampleSetIndex; }
+    void selectExampleSet(int index);
+    QStringList exampleSources(QString *examplesInstallPath, QString *demosInstallPath);
+
+signals:
+    void selectedExampleSetChanged(int);
+
+private:
+    struct ExtraExampleSet {
+        QString displayName;
+        QString manifestPath;
+        QString examplesPath;
+    };
+
     enum ExampleSetType {
         InvalidExampleSet,
         QtExampleSet,
-        ExtraExampleSet
+        ExtraExampleSetType
     };
 
-    ExampleSetModel(ExamplesListModel *examplesModel, QObject *parent);
-
     void writeCurrentIdToSettings(int currentIndex) const;
     int readCurrentIndexFromSettings() const;
 
-    int indexForQtVersion(BaseQtVersion *qtVersion) const;
-    void update();
-
     QVariant getDisplayName(int index) const;
     QVariant getId(int index) const;
     ExampleSetType getType(int i) const;
     int getQtId(int index) const;
     int getExtraExampleSetIndex(int index) const;
 
-private:
+    BaseQtVersion *findHighestQtVersion() const;
-    ExamplesListModel *examplesModel;
+
+    int indexForQtVersion(BaseQtVersion *qtVersion) const;
+    void recreateModel();
+    void updateQtVersionList();
+
+    void qtVersionManagerLoaded();
+    void helpManagerInitialized();
+    void tryToInitialize();
+
+    QList<ExtraExampleSet> m_extraExampleSets;
+    QList<BaseQtVersion*> m_qtVersions;
+    int m_selectedExampleSetIndex = -1;
+
+    bool m_qtVersionManagerInitialized = false;
+    bool m_helpManagerInitialized = false;
+    bool m_initalized = false;
 };
 
 enum InstructionalType
@@ -98,49 +125,30 @@ class ExamplesListModel : public QAbstractListModel
     Q_OBJECT
 
 public:
-    struct ExtraExampleSet {
-        QString displayName;
-        QString manifestPath;
-        QString examplesPath;
-    };
-
     explicit ExamplesListModel(QObject *parent);
 
     int rowCount(const QModelIndex &parent = QModelIndex()) const final;
     QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const final;
 
-    void beginReset() { beginResetModel(); }
+    void updateExamples();
-    void endReset() { endResetModel(); }
 
-    void update();
-
-    int selectedExampleSet() const;
-    void selectExampleSet(int index);
-
-    QList<ExtraExampleSet> extraExampleSets() const { return m_extraExampleSets; }
     QStringList exampleSets() const;
+    ExampleSetModel *exampleSetModel() { return &m_exampleSetModel; }
 
 signals:
     void selectedExampleSetChanged(int);
 
 private:
-    void updateQtVersions();
-    void updateExamples();
-
     void updateSelectedQtVersion();
-    BaseQtVersion *findHighestQtVersion() const;
 
     void parseExamples(QXmlStreamReader *reader, const QString &projectsOffset,
                                      const QString &examplesInstallPath);
     void parseDemos(QXmlStreamReader *reader, const QString &projectsOffset,
                                   const QString &demosInstallPath);
     void parseTutorials(QXmlStreamReader *reader, const QString &projectsOffset);
-    QStringList exampleSources(QString *examplesInstallPath, QString *demosInstallPath);
 
-    ExampleSetModel* m_exampleSetModel;
+    ExampleSetModel m_exampleSetModel;
-    QList<ExtraExampleSet> m_extraExampleSets;
     QList<ExampleItem> m_exampleItems;
-    int m_selectedExampleSetIndex = -1;
 };
 
 class ExamplesListModelFilter : public QSortFilterProxyModel
@@ -150,41 +158,19 @@ class ExamplesListModelFilter : public QSortFilterProxyModel
 public:
     ExamplesListModelFilter(ExamplesListModel *sourceModel, bool showTutorialsOnly, QObject *parent);
 
-    bool filterAcceptsRow(int sourceRow, const QModelIndex &sourceParent) const;
-    int rowCount(const QModelIndex &parent = QModelIndex()) const final;
-    QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const final;
-
     void setSearchString(const QString &arg);
-    void setFilterTags(const QStringList &arg);
-    void updateFilter();
-
-    void handleQtVersionsChanged();
-
-signals:
-    void filterTagsChanged(const QStringList &arg);
-    void searchStringChanged(const QString &arg);
 
 private:
-    void setFilterStrings(const QStringList &arg);
+    bool filterAcceptsRow(int sourceRow, const QModelIndex &sourceParent) const final;
+    void timerEvent(QTimerEvent *event) final;
 
-    void qtVersionManagerLoaded();
-    void helpManagerInitialized();
-
-    void exampleDataRequested() const;
-    void tryToInitialize();
-    void timerEvent(QTimerEvent *event);
     void delayedUpdateFilter();
 
     const bool m_showTutorialsOnly;
     QString m_searchString;
     QStringList m_filterTags;
     QStringList m_filterStrings;
-    ExamplesListModel *m_sourceModel;
     int m_timerId = 0;
-    bool m_qtVersionManagerInitialized = false;
-    bool m_helpManagerInitialized = false;
-    bool m_initalized = false;
-    bool m_exampleDataRequested = false;
 };
 
 } // namespace Internal

src/plugins/qtsupport/gettingstartedwelcomepage.cpp

@@ -247,7 +247,7 @@ static QString resourcePath()
 class SearchBox : public QFrame
 {
 public:
-    SearchBox(const QString &placeHolderText, QWidget *parent)
+    SearchBox(QWidget *parent)
         : QFrame(parent)
     {
         setFrameShape(QFrame::Box);
@@ -257,7 +257,6 @@ public:
         pal.setColor(QPalette::Base, themeColor(Theme::Welcome_BackgroundColor));
 
         m_lineEdit = new QLineEdit;
-        m_lineEdit->setPlaceholderText(placeHolderText);
         m_lineEdit->setFrame(false);
         m_lineEdit->setFont(sizedFont(14, this));
         m_lineEdit->setAttribute(Qt::WA_MacShowFocusRect, false);
@@ -586,44 +585,48 @@ public:
         static ExamplesListModel *s_examplesModel = new ExamplesListModel(this);
         m_examplesModel = s_examplesModel;
 
-        m_filteredModel = new ExamplesListModelFilter(m_examplesModel, !m_isExamples, this);
+        auto filteredModel = new ExamplesListModelFilter(m_examplesModel, !m_isExamples, this);
+
+        auto searchBox = new SearchBox(this);
+        m_searcher = searchBox->m_lineEdit;
 
         auto vbox = new QVBoxLayout(this);
         vbox->setContentsMargins(30, 27, 20, 20);
         if (m_isExamples) {
-            m_qtVersionSelector = new QComboBox(this);
+            m_searcher->setPlaceholderText(tr("Search in Examples..."));
-            m_qtVersionSelector->setMinimumWidth(itemWidth);
+
-            m_qtVersionSelector->setMaximumWidth(itemWidth);
+            auto exampleSetSelector = new QComboBox(this);
-            m_searchBox = new SearchBox(tr("Search in Examples..."), this);
+            exampleSetSelector->setMinimumWidth(itemWidth);
+            exampleSetSelector->setMaximumWidth(itemWidth);
+            ExampleSetModel *exampleSetModel = m_examplesModel->exampleSetModel();
+            exampleSetSelector->setModel(exampleSetModel);
+            exampleSetSelector->setCurrentIndex(exampleSetModel->selectedExampleSet());
+            connect(exampleSetSelector, static_cast<void(QComboBox::*)(int)>(&QComboBox::activated),
+                    exampleSetModel, &ExampleSetModel::selectExampleSet);
+            connect(exampleSetModel, &ExampleSetModel::selectedExampleSetChanged,
+                    exampleSetSelector, &QComboBox::setCurrentIndex);
+
             auto hbox = new QHBoxLayout;
             hbox->setSpacing(17);
-            hbox->addWidget(m_qtVersionSelector);
+            hbox->addWidget(exampleSetSelector);
-            hbox->addWidget(m_searchBox);
+            hbox->addWidget(searchBox);
             vbox->addItem(hbox);
-            connect(m_qtVersionSelector, static_cast<void(QComboBox::*)(int)>(&QComboBox::activated),
-                    m_examplesModel, &ExamplesListModel::selectExampleSet);
-            connect(m_examplesModel, &ExamplesListModel::selectedExampleSetChanged,
-                    this, &ExamplesPageWidget::updateStuff);
         } else {
-            m_searchBox = new SearchBox(tr("Search in Tutorials..."), this);
+            m_searcher->setPlaceholderText(tr("Search in Tutorials..."));
-            vbox->addWidget(m_searchBox);
+            vbox->addWidget(searchBox);
         }
 
-        m_gridModel.setSourceModel(m_filteredModel);
+        m_gridModel.setSourceModel(filteredModel);
 
-        m_gridView = new GridView(this);
+        auto gridView = new GridView(this);
-        m_gridView->setModel(&m_gridModel);
+        gridView->setModel(&m_gridModel);
-        m_gridView->setItemDelegate(&m_exampleDelegate);
+        gridView->setItemDelegate(&m_exampleDelegate);
-        vbox->addWidget(m_gridView);
+        vbox->addWidget(gridView);
 
         connect(&m_exampleDelegate, &ExampleDelegate::tagClicked,
                 this, &ExamplesPageWidget::onTagClicked);
-        connect(m_filteredModel, &ExamplesListModelFilter::filterTagsChanged,
+        connect(m_searcher, &QLineEdit::textChanged,
-                this, &ExamplesPageWidget::updateStuff);
+                filteredModel, &ExamplesListModelFilter::setSearchString);
-        connect(m_filteredModel, &ExamplesListModelFilter::searchStringChanged,
-                this, &ExamplesPageWidget::updateStuff);
-        connect(m_searchBox->m_lineEdit, &QLineEdit::textChanged,
-                m_filteredModel, &ExamplesListModelFilter::setSearchString);
     }
 
     int bestColumnCount() const
@@ -639,26 +642,14 @@ public:
 
     void onTagClicked(const QString &tag)
     {
-        QString text = m_searchBox->m_lineEdit->text();
+        QString text = m_searcher->text();
-        m_searchBox->m_lineEdit->setText(text + QString("tag:\"%1\" ").arg(tag));
+        m_searcher->setText(text + QString("tag:\"%1\" ").arg(tag));
-    }
-
-    void updateStuff()
-    {
-        if (m_isExamples) {
-            m_qtVersionSelector->clear();
-            m_qtVersionSelector->addItems(m_examplesModel->exampleSets());
-            m_qtVersionSelector->setCurrentIndex(m_examplesModel->selectedExampleSet());
-        }
     }
 
     const bool m_isExamples;
     ExampleDelegate m_exampleDelegate;
     QPointer<ExamplesListModel> m_examplesModel;
-    ExamplesListModelFilter *m_filteredModel;
+    QLineEdit *m_searcher;
-    SearchBox *m_searchBox;
-    QComboBox *m_qtVersionSelector = nullptr;
-    GridView *m_gridView;
     GridProxyModel m_gridModel;
 };