Delay widget creation of options pages till their category is shown

Also add the alternative way: IOptionsPageProvider, which states
a category, and is asked for a list of options pages for that
category when it is shown.

Task-number: QTCREATORBUG-3131

src/plugins/cmakeprojectmanager/cmakeprojectmanager.cpp

@@ -315,6 +315,8 @@ void CMakeSettingsPage::saveSettings() const
 
 void CMakeSettingsPage::apply()
 {
+    if (!m_pathchooser) // page was never shown
+        return;
     if (m_cmakeExecutable == m_pathchooser->path())
         return;
     m_cmakeExecutable = m_pathchooser->path();

src/plugins/coreplugin/actionmanager/commandmappings.cpp

@@ -54,7 +54,7 @@ using namespace Core;
 using namespace Core::Internal;
 
 CommandMappings::CommandMappings(QObject *parent)
-    : IOptionsPage(parent)
+    : IOptionsPage(parent), m_page(0)
 {
 }
 
@@ -140,7 +140,10 @@ void CommandMappings::setTargetHeader(const QString &s)
 
 void CommandMappings::finish()
 {
+    if (!m_page) // page was never shown
+        return;
     delete m_page;
+    m_page = 0;
 }
 
 void CommandMappings::commandChanged(QTreeWidgetItem *current)

src/plugins/coreplugin/dialogs/ioptionspage.cpp

@@ -34,14 +34,19 @@
   \mainclass
   \brief The IOptionsPage is an interface for providing options pages.
 
+  You need to subclass this interface and put an instance of your subclass
+  into the plugin manager object pool (e.g. ExtensionSystem::PluginManager::addObject).
   Guidelines for implementing:
   \list
-  \o id() is an id used for filtering when calling ICore:: showOptionsDialog()
-  \o displayName() is the (translated) name for display.
-  \o category() is the category used for filtering when calling ICore:: showOptionsDialog()
-  \o displayCategory() is the translated category
+  \o id() is a unique identifier for referencing this page
+  \o displayName() is the (translated) name for display
+  \o category() is the unique id for the category that the page should be displayed in
+  \o displayCategory() is the translated name of the category
+  \o createPage() is called to retrieve the widget to show in the preferences dialog
+     The widget will be destroyed by the widget hierarchy when the dialog closes
   \o apply() is called to store the settings. It should detect if any changes have been
-         made and store those.
-  \o matches() is used for the options dialog search filter.
+         made and store those
+  \o finish() is called directly before the preferences dialog closes
+  \o matches() is used for the options dialog search filter
   \endlist
 */

src/plugins/coreplugin/dialogs/ioptionspage.h

@@ -60,6 +60,29 @@ public:
     virtual void finish() = 0;
 };
 
+/*
+    Alternative way for providing option pages instead of adding IOptionsPage
+    objects into the plugin manager pool. Should only be used if creation of the
+    actual option pages is not possible or too expensive at Qt Creator startup.
+    (Like the designer integration, which needs to initialize designer plugins
+    before the options pages get available.)
+*/
+
+class CORE_EXPORT IOptionsPageProvider : public QObject
+{
+    Q_OBJECT
+
+public:
+    IOptionsPageProvider(QObject *parent = 0) : QObject(parent) {}
+    virtual ~IOptionsPageProvider() {}
+
+    virtual QString category() const = 0;
+    virtual QString displayCategory() const = 0;
+    virtual QIcon categoryIcon() const = 0;
+
+    virtual QList<IOptionsPage *> pages() const = 0;
+};
+
 } // namespace Core
 
 #endif // IOPTIONSPAGE_H

src/plugins/coreplugin/dialogs/settingsdialog.cpp

@@ -72,7 +72,8 @@ public:
     QString id;
     QString displayName;
     QIcon icon;
-    QList<IOptionsPage*> pages;
+    QList<IOptionsPage *> pages;
+    QList<IOptionsPageProvider *> providers;
     int index;
     QTabWidget *tabWidget;
 };
@@ -86,7 +87,8 @@ public:
     int rowCount(const QModelIndex &parent = QModelIndex()) const;
     QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const;
 
-    void setPages(const QList<IOptionsPage*> &pages);
+    void setPages(const QList<IOptionsPage*> &pages,
+                  const QList<IOptionsPageProvider *> &providers);
     const QList<Category*> &categories() const { return m_categories; }
 
 private:
@@ -130,7 +132,8 @@ QVariant CategoryModel::data(const QModelIndex &index, int role) const
     return QVariant();
 }
 
-void CategoryModel::setPages(const QList<IOptionsPage*> &pages)
+void CategoryModel::setPages(const QList<IOptionsPage*> &pages,
+                             const QList<IOptionsPageProvider *> &providers)
 {
     // Clear any previous categories
     qDeleteAll(m_categories);
@@ -143,13 +146,32 @@ void CategoryModel::setPages(const QList<IOptionsPage*> &pages)
         if (!category) {
             category = new Category;
             category->id = categoryId;
+            category->tabWidget = 0;
+            category->index = -1;
+            m_categories.append(category);
+        }
+        if (category->displayName.isEmpty())
             category->displayName = page->displayCategory();
+        if (category->icon.isNull())
             category->icon = page->categoryIcon();
-            category->pages.append(page);
+        category->pages.append(page);
+    }
+
+    foreach (IOptionsPageProvider *provider, providers) {
+        const QString &categoryId = provider->category();
+        Category *category = findCategoryById(categoryId);
+        if (!category) {
+            category = new Category;
+            category->id = categoryId;
+            category->tabWidget = 0;
+            category->index = -1;
             m_categories.append(category);
-        } else {
-            category->pages.append(page);
         }
+        if (category->displayName.isEmpty())
+            category->displayName = provider->displayCategory();
+        if (category->icon.isNull())
+            category->icon = provider->categoryIcon();
+        category->providers.append(provider);
     }
 
     reset();
@@ -277,26 +299,8 @@ SettingsDialog::SettingsDialog(QWidget *parent) :
     setWindowTitle(tr("Options"));
 #endif
 
-    m_model->setPages(m_pages);
-
-    // Create the tab widgets with the pages in each category
-    const QList<Category*> &categories = m_model->categories();
-    for (int i = 0; i < categories.size(); ++i) {
-        Category *category = categories.at(i);
-
-        QTabWidget *tabWidget = new QTabWidget;
-        for (int j = 0; j < category->pages.size(); ++j) {
-            IOptionsPage *page = category->pages.at(j);
-            QWidget *widget = page->createPage(0);
-            tabWidget->addTab(widget, page->displayName());
-        }
-
-        connect(tabWidget, SIGNAL(currentChanged(int)),
-                this, SLOT(currentTabChanged(int)));
-
-        category->tabWidget = tabWidget;
-        category->index = m_stackedLayout->addWidget(tabWidget);
-    }
+    m_model->setPages(m_pages,
+        ExtensionSystem::PluginManager::instance()->getObjects<IOptionsPageProvider>());
 
     m_proxyModel->setSourceModel(m_model);
     m_proxyModel->setFilterCaseSensitivity(Qt::CaseInsensitive);
@@ -383,6 +387,7 @@ void SettingsDialog::createGui()
     mainGridLayout->addWidget(buttonBox,        2, 0, 1, 2);
     mainGridLayout->setColumnStretch(1, 4);
     setLayout(mainGridLayout);
+    setMinimumSize(1070, 680);
 }
 
 SettingsDialog::~SettingsDialog()
@@ -392,7 +397,7 @@ SettingsDialog::~SettingsDialog()
 void SettingsDialog::showCategory(int index)
 {
     Category *category = m_model->categories().at(index);
-
+    ensureCategoryWidget(category);
     // Update current category and page
     m_currentCategory = category->id;
     const int currentTabIndex = category->tabWidget->currentIndex();
@@ -408,6 +413,29 @@ void SettingsDialog::showCategory(int index)
     updateEnabledTabs(category, m_filterLineEdit->text());
 }
 
+void SettingsDialog::ensureCategoryWidget(Category *category)
+{
+    if (category->tabWidget != 0)
+        return;
+    foreach (const IOptionsPageProvider *provider, category->providers) {
+        category->pages += provider->pages();
+    }
+    qStableSort(category->pages.begin(), category->pages.end(), optionsPageLessThan);
+
+    QTabWidget *tabWidget = new QTabWidget;
+    for (int j = 0; j < category->pages.size(); ++j) {
+        IOptionsPage *page = category->pages.at(j);
+        QWidget *widget = page->createPage(0);
+        tabWidget->addTab(widget, page->displayName());
+    }
+
+    connect(tabWidget, SIGNAL(currentChanged(int)),
+            this, SLOT(currentTabChanged(int)));
+
+    category->tabWidget = tabWidget;
+    category->index = m_stackedLayout->addWidget(tabWidget);
+}
+
 void SettingsDialog::updateEnabledTabs(Category *category, const QString &searchText)
 {
     for (int i = 0; i < category->pages.size(); ++i) {

src/plugins/coreplugin/dialogs/settingsdialog.h

@@ -93,6 +93,7 @@ private:
     void showCategory(int index);
     void showPage(const QString &categoryId, const QString &pageId);
     void updateEnabledTabs(Category *category, const QString &searchText);
+    void ensureCategoryWidget(Category *category);
 
     const QList<Core::IOptionsPage*> m_pages;
 

src/plugins/coreplugin/generalsettings.cpp

@@ -53,7 +53,7 @@ using namespace Core::Internal;
 
 
 GeneralSettings::GeneralSettings():
-    m_dialog(0)
+    m_page(0), m_dialog(0)
 {
 }
 
@@ -188,6 +188,8 @@ bool GeneralSettings::matches(const QString &s) const
 
 void GeneralSettings::apply()
 {
+    if (!m_page) // wasn't shown, can't be changed
+        return;
     int currentIndex = m_page->languageBox->currentIndex();
     setLanguage(m_page->languageBox->itemData(currentIndex, Qt::UserRole).toString());
     // Apply the new base color if accepted
@@ -205,7 +207,10 @@ void GeneralSettings::apply()
 
 void GeneralSettings::finish()
 {
+    if (!m_page) // page was never shown
+        return;
     delete m_page;
+    m_page = 0;
 }
 
 void GeneralSettings::resetInterfaceColor()

src/plugins/cpaster/fileshareprotocolsettingspage.cpp

@@ -96,7 +96,7 @@ FileShareProtocolSettings FileShareProtocolSettingsWidget::settings() const
 // ----------FileShareProtocolSettingsPage
 FileShareProtocolSettingsPage::FileShareProtocolSettingsPage(const QSharedPointer<FileShareProtocolSettings> &s,
                                                              QObject *parent) :
-    Core::IOptionsPage(parent), m_settings(s)
+    Core::IOptionsPage(parent), m_settings(s), m_widget(0)
 {
 }
 
@@ -134,6 +134,8 @@ QWidget *FileShareProtocolSettingsPage::createPage(QWidget *parent)
 
 void FileShareProtocolSettingsPage::apply()
 {
+    if (!m_widget) // page was never shown
+        return;
     const FileShareProtocolSettings newSettings = m_widget->settings();
     if (newSettings != *m_settings) {
         *m_settings = newSettings;

src/plugins/cpaster/settingspage.cpp

@@ -76,7 +76,7 @@ Settings SettingsWidget::settings()
 }
 
 SettingsPage::SettingsPage(const QSharedPointer<Settings> &settings) :
-    m_settings(settings)
+    m_settings(settings), m_widget(0)
 {
 }
 
@@ -121,7 +121,8 @@ QWidget *SettingsPage::createPage(QWidget *parent)
 
 void SettingsPage::apply()
 {
-    QTC_ASSERT(m_widget, return)
+    if (!m_widget) // page was never shown
+        return;
     const Settings newSettings = m_widget->settings();
     if (newSettings != *m_settings) {
         *m_settings = newSettings;

src/plugins/cpptools/completionsettingspage.cpp

@@ -40,7 +40,7 @@
 using namespace CppTools::Internal;
 
 CompletionSettingsPage::CompletionSettingsPage()
-    : m_page(new Ui_CompletionSettingsPage)
+    : m_page(0)
 {
 }
 
@@ -62,6 +62,7 @@ QString CompletionSettingsPage::displayName() const
 QWidget *CompletionSettingsPage::createPage(QWidget *parent)
 {
     QWidget *w = new QWidget(parent);
+    m_page = new Ui_CompletionSettingsPage;
     m_page->setupUi(w);
 
     const TextEditor::CompletionSettings &settings =
@@ -113,6 +114,8 @@ QWidget *CompletionSettingsPage::createPage(QWidget *parent)
 
 void CompletionSettingsPage::apply()
 {
+    if (!m_page) // page was never shown
+        return;
     TextEditor::CompletionSettings settings;
     settings.m_caseSensitivity = caseSensitivity();
     settings.m_completionTrigger = completionTrigger();
@@ -151,3 +154,11 @@ TextEditor::CompletionTrigger CompletionSettingsPage::completionTrigger() const
         return TextEditor::AutomaticCompletion;
     }
 }
+
+void CompletionSettingsPage::finish()
+{
+    if (!m_page) // page was never shown
+        return;
+    delete m_page;
+    m_page = 0;
+}

src/plugins/cpptools/completionsettingspage.h

@@ -55,7 +55,7 @@ public:
 
     QWidget *createPage(QWidget *parent);
     void apply();
-    void finish() { }
+    void finish();
     virtual bool matches(const QString &) const;
 
 private:

src/plugins/debugger/gdb/gdboptionspage.cpp

@@ -139,6 +139,7 @@ void GdbOptionsPage::writeGdbBinarySettings() /* static */
 }
 
 GdbOptionsPage::GdbOptionsPage()
+    : m_ui(0)
 {
 }
 
@@ -170,67 +171,68 @@ QIcon GdbOptionsPage::categoryIcon() const
 QWidget *GdbOptionsPage::createPage(QWidget *parent)
 {
     QWidget *w = new QWidget(parent);
-    m_ui.setupUi(w);
-    m_ui.gdbChooserWidget->setGdbBinaries(gdbBinaryToolChainMap);
-    m_ui.scriptFileChooser->setExpectedKind(Utils::PathChooser::File);
-    m_ui.scriptFileChooser->setPromptDialogTitle(tr("Choose Location of Startup Script File"));
+    m_ui = new Ui::GdbOptionsPage;
+    m_ui->setupUi(w);
+    m_ui->gdbChooserWidget->setGdbBinaries(gdbBinaryToolChainMap);
+    m_ui->scriptFileChooser->setExpectedKind(Utils::PathChooser::File);
+    m_ui->scriptFileChooser->setPromptDialogTitle(tr("Choose Location of Startup Script File"));
 
     m_group.clear();
     m_group.insert(debuggerCore()->action(GdbScriptFile),
-        m_ui.scriptFileChooser);
+        m_ui->scriptFileChooser);
     m_group.insert(debuggerCore()->action(GdbEnvironment),
-        m_ui.environmentEdit);
+        m_ui->environmentEdit);
     m_group.insert(debuggerCore()->action(AdjustBreakpointLocations),
-        m_ui.checkBoxAdjustBreakpointLocations);
+        m_ui->checkBoxAdjustBreakpointLocations);
     m_group.insert(debuggerCore()->action(GdbWatchdogTimeout),
-        m_ui.spinBoxGdbWatchdogTimeout);
+        m_ui->spinBoxGdbWatchdogTimeout);
 
     m_group.insert(debuggerCore()->action(UseMessageBoxForSignals),
-        m_ui.checkBoxUseMessageBoxForSignals);
+        m_ui->checkBoxUseMessageBoxForSignals);
     m_group.insert(debuggerCore()->action(SkipKnownFrames),
-        m_ui.checkBoxSkipKnownFrames);
+        m_ui->checkBoxSkipKnownFrames);
     m_group.insert(debuggerCore()->action(EnableReverseDebugging),
-        m_ui.checkBoxEnableReverseDebugging);
+        m_ui->checkBoxEnableReverseDebugging);
     m_group.insert(debuggerCore()->action(GdbWatchdogTimeout), 0);
 
 #if 1
-    m_ui.groupBoxPluginDebugging->hide();
+    m_ui->groupBoxPluginDebugging->hide();
 #else // The related code (handleAqcuiredInferior()) is disabled as well.
     m_group.insert(debuggerCore()->action(AllPluginBreakpoints),
-        m_ui.radioButtonAllPluginBreakpoints);
+        m_ui->radioButtonAllPluginBreakpoints);
     m_group.insert(debuggerCore()->action(SelectedPluginBreakpoints),
-        m_ui.radioButtonSelectedPluginBreakpoints);
+        m_ui->radioButtonSelectedPluginBreakpoints);
     m_group.insert(debuggerCore()->action(NoPluginBreakpoints),
-        m_ui.radioButtonNoPluginBreakpoints);
+        m_ui->radioButtonNoPluginBreakpoints);
     m_group.insert(debuggerCore()->action(SelectedPluginBreakpointsPattern),
-        m_ui.lineEditSelectedPluginBreakpointsPattern);
+        m_ui->lineEditSelectedPluginBreakpointsPattern);
 #endif
 
-    m_ui.lineEditSelectedPluginBreakpointsPattern->
+    m_ui->lineEditSelectedPluginBreakpointsPattern->
         setEnabled(debuggerCore()->action(SelectedPluginBreakpoints)->value().toBool());
-    connect(m_ui.radioButtonSelectedPluginBreakpoints, SIGNAL(toggled(bool)),
-        m_ui.lineEditSelectedPluginBreakpointsPattern, SLOT(setEnabled(bool)));
+    connect(m_ui->radioButtonSelectedPluginBreakpoints, SIGNAL(toggled(bool)),
+        m_ui->lineEditSelectedPluginBreakpointsPattern, SLOT(setEnabled(bool)));
 
     // FIXME
-    m_ui.environmentEdit->hide();
-    m_ui.labelEnvironment->hide();
+    m_ui->environmentEdit->hide();
+    m_ui->labelEnvironment->hide();
 
     if (m_searchKeywords.isEmpty()) {
         QLatin1Char sep(' ');
         QTextStream(&m_searchKeywords)
-                << sep << m_ui.groupBoxLocations->title()
-                << sep << m_ui.labelEnvironment->text()
-                << sep << m_ui.labelGdbStartupScript->text()
-                << sep << m_ui.labelGdbWatchdogTimeout->text()
-                << sep << m_ui.checkBoxEnableReverseDebugging->text()
-                << sep << m_ui.checkBoxSkipKnownFrames->text()
-                << sep << m_ui.checkBoxUseMessageBoxForSignals->text()
-                << sep << m_ui.checkBoxAdjustBreakpointLocations->text()
-                << sep << m_ui.groupBoxPluginDebugging->title()
-                << sep << m_ui.radioButtonAllPluginBreakpoints->text()
-                << sep << m_ui.radioButtonSelectedPluginBreakpoints->text()
-                << sep << m_ui.labelSelectedPluginBreakpoints->text()
-                << sep << m_ui.radioButtonNoPluginBreakpoints->text()
+                << sep << m_ui->groupBoxLocations->title()
+                << sep << m_ui->labelEnvironment->text()
+                << sep << m_ui->labelGdbStartupScript->text()
+                << sep << m_ui->labelGdbWatchdogTimeout->text()
+                << sep << m_ui->checkBoxEnableReverseDebugging->text()
+                << sep << m_ui->checkBoxSkipKnownFrames->text()
+                << sep << m_ui->checkBoxUseMessageBoxForSignals->text()
+                << sep << m_ui->checkBoxAdjustBreakpointLocations->text()
+                << sep << m_ui->groupBoxPluginDebugging->title()
+                << sep << m_ui->radioButtonAllPluginBreakpoints->text()
+                << sep << m_ui->radioButtonSelectedPluginBreakpoints->text()
+                << sep << m_ui->labelSelectedPluginBreakpoints->text()
+                << sep << m_ui->radioButtonNoPluginBreakpoints->text()
                    ;
         m_searchKeywords.remove(QLatin1Char('&'));
     }
@@ -239,17 +241,22 @@ QWidget *GdbOptionsPage::createPage(QWidget *parent)
 
 void GdbOptionsPage::apply()
 {
+    if (!m_ui) // page never shown
+        return;
     m_group.apply(Core::ICore::instance()->settings());
-
-    if (m_ui.gdbChooserWidget->isDirty()) {
+    if (m_ui->gdbChooserWidget->isDirty()) {
         gdbBinariesChanged = true;
-        gdbBinaryToolChainMap = m_ui.gdbChooserWidget->gdbBinaries();
-        m_ui.gdbChooserWidget->clearDirty();
+        gdbBinaryToolChainMap = m_ui->gdbChooserWidget->gdbBinaries();
+        m_ui->gdbChooserWidget->clearDirty();
     }
 }
 
 void GdbOptionsPage::finish()
 {
+    if (!m_ui) // page never shown
+        return;
+    delete m_ui;
+    m_ui = 0;
     m_group.finish();
 }
 

src/plugins/debugger/gdb/gdboptionspage.h

@@ -64,7 +64,7 @@ public:
     static void writeGdbBinarySettings();
 
 private:
-    Ui::GdbOptionsPage m_ui;
+    Ui::GdbOptionsPage *m_ui;
     Utils::SavedActionSet m_group;
     QString m_searchKeywords;
 };

src/plugins/designer/formeditorplugin.cpp

@@ -37,6 +37,7 @@
 #  include "cppsettingspage.h"
 #endif
 
+#include "settingspage.h"
 #include "designerconstants.h"
 
 #include <coreplugin/icore.h>
@@ -84,6 +85,7 @@ bool FormEditorPlugin::initialize(const QStringList &arguments, QString *error)
     initializeTemplates();
 
     addAutoReleasedObject(new FormEditorFactory);
+    addAutoReleasedObject(new SettingsPageProvider);
 
     // Ensure that loading designer translations is done before FormEditorW is instantiated
     const QString locale = Core::ICore::instance()->userInterfaceLanguage();
@@ -97,18 +99,9 @@ bool FormEditorPlugin::initialize(const QStringList &arguments, QString *error)
             qApp->installTranslator(qtr);
     }
     error->clear();
-    // Delayed loading: Make sure settings pages are there if options
-    // dialog is requested.
-    connect(Core::ICore::instance(), SIGNAL(optionsDialogRequested()),
-            this, SLOT(ensurePluginInitialized()));
     return true;
 }
 
-void FormEditorPlugin::ensurePluginInitialized()
-{
-    FormEditorW::instance()->ensureInitStage(FormEditorW::RegisterPlugins);
-}
-
 void FormEditorPlugin::extensionsInitialized()
 {
     // 4) test and make sure everything works (undo, saving, editors, opening/closing multiple files, dirtiness etc)

src/plugins/designer/formeditorplugin.h

@@ -57,9 +57,6 @@ public:
     bool initialize(const QStringList &arguments, QString *error_message = 0);
     void extensionsInitialized();
 
-public slots:
-    void ensurePluginInitialized();
-
 private:
 
     void initializeTemplates();

src/plugins/designer/formeditorw.cpp

@@ -186,7 +186,6 @@ FormEditorW::FormEditorW() :
 
     foreach (QDesignerOptionsPageInterface *designerPage, m_formeditor->optionsPages()) {
         SettingsPage *settingsPage = new SettingsPage(designerPage);
-        ExtensionSystem::PluginManager::instance()->addObject(settingsPage);
         m_settingsPages.append(settingsPage);
     }
 
@@ -213,10 +212,8 @@ FormEditorW::~FormEditorW()
     }
 
     delete m_formeditor;
-    foreach (SettingsPage *settingsPage, m_settingsPages) {
-        ExtensionSystem::PluginManager::instance()->removeObject(settingsPage);
-        delete settingsPage;
-    }
+    qDeleteAll(m_settingsPages);
+    m_settingsPages.clear();
     delete m_integration;
 
     m_self = 0;
@@ -389,6 +386,11 @@ void FormEditorW::initDesignerSubWindows()
     m_designerSubWindows[ActionEditorSubWindow] = ae;
 }
 
+QList<Core::IOptionsPage *> FormEditorW::optionsPages() const
+{
+    return m_settingsPages;
+}
+
 void FormEditorW::ensureInitStage(InitializationStage s)
 {
     if (Designer::Constants::Internal::debug)

src/plugins/designer/formeditorw.h

@@ -32,7 +32,8 @@
 
 #include "designerconstants.h"
 
-#include "coreplugin/icontext.h"
+#include <coreplugin/icontext.h>
+#include <coreplugin/dialogs/ioptionspage.h>
 
 #include <QtCore/QMap>
 #include <QtCore/QObject>
@@ -85,12 +86,10 @@ class DesignerContext;
   * The plugin uses this stage at first by calling ensureInitStage().
   * Requesting an editor via instance() will fully initialize the class.
   * This is based on the assumption that the Designer settings work with
-  * no plugins loaded. If that does not work, full initialization can be
-  * triggered by connection to the ICore::optionsDialogRequested() signal.
+  * no plugins loaded.
   *
   * The form editor shows a read-only XML editor in edit mode and Qt Designer
-  * in Desig