diff --git a/plugins/quickopen/quickopenwidget.cpp b/plugins/quickopen/quickopenwidget.cpp
index 38d2b4d602..3cc9e9f085 100644
--- a/plugins/quickopen/quickopenwidget.cpp
+++ b/plugins/quickopen/quickopenwidget.cpp
@@ -1,515 +1,515 @@
 /*
  * This file is part of KDevelop
  *
  * Copyright 2007 David Nolden <david.nolden.kdevelop@art-master.de>
  * Copyright 2016 Kevin Funk <kfunk@kde.org>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU Library General Public License as
  * published by the Free Software Foundation; either version 2 of the
  * License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public
  * License along with this program; if not, write to the
  * Free Software Foundation, Inc.,
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
 #include "quickopenwidget.h"
 #include <KParts/MainWindow>
 #include "debug.h"
 
 #include "expandingtree/expandingdelegate.h"
 #include "quickopenmodel.h"
 
 #include <icore.h>
 #include <iuicontroller.h>
 
 #include <QDialog>
 #include <QMenuBar>
 #include <QKeyEvent>
 #include <QScrollBar>
 
 #include <KTextEditor/CodeCompletionModel>
 
 using namespace KDevelop;
 
 class QuickOpenDelegate : public ExpandingDelegate {
     Q_OBJECT
 public:
   QuickOpenDelegate(ExpandingWidgetModel* model, QObject* parent = 0L) : ExpandingDelegate(model, parent) {
   }
   QList<QTextLayout::FormatRange> createHighlighting(const QModelIndex& index, QStyleOptionViewItem& option) const override {
     QList<QVariant> highlighting = index.data(KTextEditor::CodeCompletionModel::CustomHighlight).toList();
     if(!highlighting.isEmpty())
       return highlightingFromVariantList(highlighting);
     return ExpandingDelegate::createHighlighting( index, option );
   }
 
 };
 
 QuickOpenWidget::QuickOpenWidget( QString title, QuickOpenModel* model, const QStringList& initialItems, const QStringList& initialScopes, bool listOnly, bool noSearchField )
   : m_model(model)
   , m_expandedTemporary(false)
   , m_hadNoCommandSinceAlt(true)
 {
   m_filterTimer.setSingleShot(true);
   connect(&m_filterTimer, &QTimer::timeout, this, &QuickOpenWidget::applyFilter);
 
   Q_UNUSED( title );
   ui.setupUi( this );
   ui.list->header()->hide();
   ui.list->setRootIsDecorated( false );
   ui.list->setVerticalScrollMode( QAbstractItemView::ScrollPerItem );
 
   connect(ui.list->verticalScrollBar(), &QScrollBar::valueChanged, m_model, &QuickOpenModel::placeExpandingWidgets);
 
   ui.searchLine->setFocus();
 
   ui.list->setItemDelegate( new QuickOpenDelegate( m_model, ui.list ) );
 
   if(!listOnly) {
     QStringList allTypes = m_model->allTypes();
     QStringList allScopes = m_model->allScopes();
 
     QMenu* itemsMenu = new QMenu(this);
 
     foreach( const QString &type, allTypes )
     {
       QAction* action = new QAction(type, itemsMenu);
       action->setCheckable(true);
       action->setChecked(initialItems.isEmpty() || initialItems.contains( type ));
       connect( action, &QAction::toggled, this, &QuickOpenWidget::updateProviders, Qt::QueuedConnection );
       itemsMenu->addAction(action);
     }
 
     ui.itemsButton->setMenu(itemsMenu);
 
     QMenu* scopesMenu = new QMenu(this);
 
     foreach( const QString &scope, allScopes )
     {
       QAction* action = new QAction(scope, scopesMenu);
       action->setCheckable(true);
       action->setChecked(initialScopes.isEmpty() || initialScopes.contains( scope ) );
 
       connect( action, &QAction::toggled, this, &QuickOpenWidget::updateProviders, Qt::QueuedConnection );
       scopesMenu->addAction(action);
     }
 
     ui.scopesButton->setMenu(scopesMenu);
 
   }else{
     ui.list->setFocusPolicy(Qt::StrongFocus);
     ui.scopesButton->hide();
     ui.itemsButton->hide();
     ui.label->hide();
     ui.label_2->hide();
   }
 
   showSearchField(!noSearchField);
 
   ui.okButton->hide();
   ui.cancelButton->hide();
 
   ui.searchLine->installEventFilter( this );
   ui.list->installEventFilter( this );
   ui.list->setFocusPolicy(Qt::NoFocus);
   ui.scopesButton->setFocusPolicy(Qt::NoFocus);
   ui.itemsButton->setFocusPolicy(Qt::NoFocus);
 
   connect( ui.searchLine, &QLineEdit::textChanged, this, &QuickOpenWidget::textChanged );
 
   connect( ui.list, &ExpandingTree::doubleClicked, this, &QuickOpenWidget::doubleClicked );
 
   connect(ui.okButton, &QPushButton::clicked, this, &QuickOpenWidget::accept);
   connect(ui.okButton, &QPushButton::clicked, this, &QuickOpenWidget::ready);
   connect(ui.cancelButton, &QPushButton::clicked, this, &QuickOpenWidget::ready);
 
   updateProviders();
   updateTimerInterval(true);
 
 // no need to call this, it's done by updateProviders already
 //   m_model->restart();
 }
 
 void QuickOpenWidget::showStandardButtons(bool show)
 {
   if(show) {
     ui.okButton->show();
     ui.cancelButton->show();
   }else{
     ui.okButton->hide();
     ui.cancelButton->hide();
   }
 }
 
 void QuickOpenWidget::updateTimerInterval(bool cheapFilterChange)
 {
   const int MAX_ITEMS = 10000;
   if ( cheapFilterChange && m_model->rowCount(QModelIndex()) < MAX_ITEMS ) {
     // cheap change and there are currently just a few items,
     // so apply filter instantly
     m_filterTimer.setInterval(0);
   } else if ( m_model->unfilteredRowCount() < MAX_ITEMS ) {
     // not a cheap change, but there are generally
     // just a few items in the list: apply filter instantly
     m_filterTimer.setInterval(0);
   } else {
     // otherwise use a timer to prevent sluggishness while typing
     m_filterTimer.setInterval(300);
   }
 }
 
 void QuickOpenWidget::showEvent(QShowEvent* e)
 {
     QWidget::showEvent(e);
 
     // The column width only has an effect _after_ the widget has been shown
     ui.list->setColumnWidth( 0, 20 );
 }
 
 void QuickOpenWidget::setAlternativeSearchField(QLineEdit* alterantiveSearchField)
 {
     ui.searchLine = alterantiveSearchField;
     ui.searchLine->installEventFilter( this );
     connect( ui.searchLine, &QLineEdit::textChanged, this, &QuickOpenWidget::textChanged );
 }
 
 
 void QuickOpenWidget::showSearchField(bool b)
 {
   if(b){
     ui.searchLine->show();
     ui.searchLabel->show();
   }else{
     ui.searchLine->hide();
     ui.searchLabel->hide();
   }
 }
 
 void QuickOpenWidget::prepareShow()
 {
   ui.list->setModel( 0 );
   ui.list->setVerticalScrollMode(QAbstractItemView::ScrollPerItem);
   m_model->setTreeView( ui.list );
   ui.list->setModel( m_model );
 
   m_filterTimer.stop();
   m_filter = QString();
 
   if (!m_preselectedText.isEmpty())
   {
     ui.searchLine->setText(m_preselectedText);
     ui.searchLine->selectAll();
   }
 
   m_model->restart(false);
 
   connect( ui.list->selectionModel(), &QItemSelectionModel::currentRowChanged,
            this, &QuickOpenWidget::callRowSelected );
   connect( ui.list->selectionModel(), &QItemSelectionModel::selectionChanged,
            this, &QuickOpenWidget::callRowSelected );
 }
 
 void QuickOpenWidgetDialog::run() {
   m_widget->prepareShow();
   m_dialog->show();
 }
 
 QuickOpenWidget::~QuickOpenWidget() {
   m_model->setTreeView( 0 );
 }
 
 
 QuickOpenWidgetDialog::QuickOpenWidgetDialog(QString title, QuickOpenModel* model, const QStringList& initialItems, const QStringList& initialScopes, bool listOnly, bool noSearchField)
 {
   m_widget = new QuickOpenWidget(title, model, initialItems, initialScopes, listOnly, noSearchField);
   // the QMenu might close on esc and we want to close the whole dialog then
   connect( m_widget, &QuickOpenWidget::aboutToHide, this, &QuickOpenWidgetDialog::deleteLater );
 
   m_dialog = new QDialog( ICore::self()->uiController()->activeMainWindow() );
   m_dialog->resize(QSize(800, 400));
 
   m_dialog->setWindowTitle(title);
   QVBoxLayout* layout = new QVBoxLayout(m_dialog);
   layout->addWidget(m_widget);
   m_widget->showStandardButtons(true);
   connect(m_widget, &QuickOpenWidget::ready, m_dialog, &QDialog::close);
   connect( m_dialog, &QDialog::accepted, m_widget, &QuickOpenWidget::accept );
 }
 
 
 QuickOpenWidgetDialog::~QuickOpenWidgetDialog()
 {
   delete m_dialog;
 }
 
 void QuickOpenWidget::setPreselectedText(const QString& text)
 {
   m_preselectedText = text;
 }
 
 void QuickOpenWidget::updateProviders() {
-  if(QAction* action = qobject_cast<QAction*>(sender())) {
+  if(QAction* action = (sender() ? qobject_cast<QAction*>(sender()) : nullptr)) {
     QMenu* menu = qobject_cast<QMenu*>(action->parentWidget());
     if(menu) {
       menu->show();
       menu->setActiveAction(action);
     }
   }
 
   QStringList checkedItems;
 
   if(ui.itemsButton->menu()) {
 
     foreach( QObject* obj, ui.itemsButton->menu()->children() ) {
       QAction* box = qobject_cast<QAction*>( obj );
       if( box ) {
         if( box->isChecked() )
           checkedItems << box->text().remove('&');
       }
     }
         ui.itemsButton->setText(checkedItems.join(QStringLiteral(", ")));
   }
 
   QStringList checkedScopes;
 
   if(ui.scopesButton->menu()) {
 
     foreach( QObject* obj, ui.scopesButton->menu()->children() ) {
       QAction* box = qobject_cast<QAction*>( obj );
       if( box ) {
         if( box->isChecked() )
           checkedScopes << box->text().remove('&');
       }
     }
 
     ui.scopesButton->setText(checkedScopes.join(QStringLiteral(", ")));
   }
 
   emit itemsChanged( checkedItems );
   emit scopesChanged( checkedScopes );
   m_model->enableProviders( checkedItems, checkedScopes );
 }
 
 void QuickOpenWidget::textChanged( const QString& str )
 {
   // "cheap" when something was just appended to the current filter
   updateTimerInterval(str.startsWith(m_filter));
   m_filter = str;
   m_filterTimer.start();
 }
 
 void QuickOpenWidget::applyFilter()
 {
   m_model->textChanged( m_filter );
 
   QModelIndex currentIndex = m_model->index(0, 0, QModelIndex());
     ui.list->selectionModel()->setCurrentIndex( currentIndex, QItemSelectionModel::ClearAndSelect | QItemSelectionModel::Rows | QItemSelectionModel::Current );
 
   callRowSelected();
 }
 
 void QuickOpenWidget::callRowSelected() {
   QModelIndex currentIndex = ui.list->selectionModel()->currentIndex();
   if( currentIndex.isValid() )
     m_model->rowSelected( currentIndex );
   else
     qCDebug(PLUGIN_QUICKOPEN) << "current index is not valid";
 }
 
 void QuickOpenWidget::accept() {
   QString filterText = ui.searchLine->text();
   m_model->execute( ui.list->currentIndex(), filterText );
 }
 
 void QuickOpenWidget::doubleClicked ( const QModelIndex & index ) {
   // crash guard: https://bugs.kde.org/show_bug.cgi?id=297178
     ui.list->setCurrentIndex(index);
   QMetaObject::invokeMethod(this, "accept", Qt::QueuedConnection);
   QMetaObject::invokeMethod(this, "ready", Qt::QueuedConnection);
 }
 
 void QuickOpenWidget::avoidMenuAltFocus() {
     // send an invalid key event to the main menu bar. The menu bar will
     // stop listening when observing another key than ALT between the press
     // and the release.
     QKeyEvent event1(QEvent::KeyPress, 0, Qt::NoModifier);
     QApplication::sendEvent(ICore::self()->uiController()->activeMainWindow()->menuBar(), &event1);
     QKeyEvent event2(QEvent::KeyRelease, 0, Qt::NoModifier);
     QApplication::sendEvent(ICore::self()->uiController()->activeMainWindow()->menuBar(), &event2);
 }
 
 bool QuickOpenWidget::eventFilter ( QObject * watched, QEvent * event )
 {
   QKeyEvent *keyEvent = dynamic_cast<QKeyEvent*>(event);
 
   if( event->type() == QEvent::KeyRelease ) {
     if(keyEvent->key() == Qt::Key_Alt) {
       if((m_expandedTemporary && m_altDownTime.msecsTo( QTime::currentTime() ) > 300) || (!m_expandedTemporary && m_altDownTime.msecsTo( QTime::currentTime() ) < 300 && m_hadNoCommandSinceAlt)) {
         //Unexpand the item
         QModelIndex row = ui.list->selectionModel()->currentIndex();
         if( row.isValid() ) {
           row = row.sibling( row.row(), 0 );
           if(m_model->isExpanded( row ))
             m_model->setExpanded( row, false );
         }
       }
       m_expandedTemporary = false;
     }
   }
 
   if( event->type() == QEvent::KeyPress  ) {
     m_hadNoCommandSinceAlt = false;
     if(keyEvent->key() == Qt::Key_Alt) {
       avoidMenuAltFocus();
       m_hadNoCommandSinceAlt = true;
       //Expand
       QModelIndex row = ui.list->selectionModel()->currentIndex();
       if( row.isValid() ) {
         row = row.sibling( row.row(), 0 );
         m_altDownTime = QTime::currentTime();
         if(!m_model->isExpanded( row )) {
           m_expandedTemporary = true;
           m_model->setExpanded( row, true );
         }
       }
     }
 
     switch( keyEvent->key() ) {
       case Qt::Key_Tab:
         if ( keyEvent->modifiers() == Qt::NoModifier ) {
           // Tab should work just like Down
           QCoreApplication::sendEvent(ui.list, new QKeyEvent(QEvent::KeyPress, Qt::Key_Down, Qt::NoModifier));
           QCoreApplication::sendEvent(ui.list, new QKeyEvent(QEvent::KeyRelease, Qt::Key_Down, Qt::NoModifier));
           return true;
         }
         break;
       case Qt::Key_Backtab:
          if ( keyEvent->modifiers() == Qt::ShiftModifier ) {
           // Shift + Tab should work just like Up
           QCoreApplication::sendEvent(ui.list, new QKeyEvent(QEvent::KeyPress, Qt::Key_Up, Qt::NoModifier));
           QCoreApplication::sendEvent(ui.list, new QKeyEvent(QEvent::KeyRelease, Qt::Key_Up, Qt::NoModifier));
           return true;
         }
         break;
       case Qt::Key_Down:
       case Qt::Key_Up:
       {
         if( keyEvent->modifiers() == Qt::AltModifier ) {
           QWidget* w = m_model->expandingWidget(ui.list->selectionModel()->currentIndex());
           if( KDevelop::QuickOpenEmbeddedWidgetInterface* interface =
               dynamic_cast<KDevelop::QuickOpenEmbeddedWidgetInterface*>( w ) ){
             if( keyEvent->key() == Qt::Key_Down )
               interface->down();
             else
               interface->up();
             return true;
           }
           return false;
         }
       }
       case Qt::Key_PageUp:
       case Qt::Key_PageDown:
         if(watched == ui.list )
           return false;
         QApplication::sendEvent( ui.list, event );
       //callRowSelected();
         return true;
 
       case Qt::Key_Left: {
         //Expand/unexpand
         if( keyEvent->modifiers() == Qt::AltModifier ) {
           //Eventually Send action to the widget
           QWidget* w = m_model->expandingWidget(ui.list->selectionModel()->currentIndex());
           if( KDevelop::QuickOpenEmbeddedWidgetInterface* interface =
               dynamic_cast<KDevelop::QuickOpenEmbeddedWidgetInterface*>( w ) ){
             interface->previous();
             return true;
           }
         } else {
           QModelIndex row = ui.list->selectionModel()->currentIndex();
           if( row.isValid() ) {
             row = row.sibling( row.row(), 0 );
 
             if( m_model->isExpanded( row ) ) {
               m_model->setExpanded( row, false );
               return true;
             }
           }
         }
         return false;
       }
       case Qt::Key_Right: {
         //Expand/unexpand
         if( keyEvent->modifiers() == Qt::AltModifier ) {
           //Eventually Send action to the widget
           QWidget* w = m_model->expandingWidget(ui.list->selectionModel()->currentIndex());
           if( KDevelop::QuickOpenEmbeddedWidgetInterface* interface =
               dynamic_cast<KDevelop::QuickOpenEmbeddedWidgetInterface*>( w ) ){
             interface->next();
             return true;
           }
         } else {
           QModelIndex row = ui.list->selectionModel()->currentIndex();
           if( row.isValid() ) {
             row = row.sibling( row.row(), 0 );
 
             if( !m_model->isExpanded( row ) ) {
               m_model->setExpanded( row, true );
               return true;
             }
           }
         }
         return false;
       }
       case Qt::Key_Return:
       case Qt::Key_Enter: {
         if (m_filterTimer.isActive()) {
           m_filterTimer.stop();
           applyFilter();
         }
         if( keyEvent->modifiers() == Qt::AltModifier ) {
           //Eventually Send action to the widget
           QWidget* w = m_model->expandingWidget(ui.list->selectionModel()->currentIndex());
           if( KDevelop::QuickOpenEmbeddedWidgetInterface* interface =
               dynamic_cast<KDevelop::QuickOpenEmbeddedWidgetInterface*>( w ) ){
             interface->accept();
             return true;
           }
         } else {
           QString filterText = ui.searchLine->text();
 
           //Safety: Track whether this object is deleted. When execute() is called, a dialog may be opened,
           //which kills the quickopen widget.
           QPointer<QObject> stillExists(this);
 
           if( m_model->execute( ui.list->currentIndex(), filterText ) ) {
 
             if(!stillExists)
               return true;
 
             if(!(keyEvent->modifiers() & Qt::ShiftModifier))
               emit ready();
           } else {
             //Maybe the filter-text was changed:
             if( filterText != ui.searchLine->text() ) {
               ui.searchLine->setText( filterText );
             }
           }
         }
         return true;
       }
     }
   }
 
   return false;
 }
 
 #include "quickopenwidget.moc"