diff --git a/aard.cc b/aard.cc
index e41433c7..5a2d9e8b 100644
--- a/aard.cc
+++ b/aard.cc
@@ -940,8 +940,7 @@ vector< sptr< Dictionary::Class > > makeDictionaries(
           quint16 volumes = qFromBigEndian( dictHeader.totalVolumes );
           if( volumes > 1 )
           {
-            QString ss;
-            ss.sprintf( " (%i/%i)", qFromBigEndian( dictHeader.volume ), volumes );
+            QString ss=QString( " (%1/%2)").arg( qFromBigEndian( dictHeader.volume ), volumes );
             dictName += ss.toLocal8Bit().data();
           }
 
diff --git a/article_netmgr.cc b/article_netmgr.cc
index c88d1d22..ae74740b 100644
--- a/article_netmgr.cc
+++ b/article_netmgr.cc
@@ -32,7 +32,7 @@ using std::string;
 
     connect( baseReply, SIGNAL( metaDataChanged() ), this, SLOT( applyMetaData() ) );
 
-    connect( baseReply, SIGNAL( error( QNetworkReply::NetworkError) ),
+    connect( baseReply, SIGNAL( errorOccurred( QNetworkReply::NetworkError) ),
              this, SLOT( applyError( QNetworkReply::NetworkError ) ) );
 
     connect( baseReply, SIGNAL( readyRead() ), this, SLOT( readDataFromBase() ) );
@@ -113,8 +113,8 @@ using std::string;
                   baseReply->attribute( QNetworkRequest::HttpPipeliningWasUsedAttribute ) );
     setAttribute( QNetworkRequest::BackgroundRequestAttribute,
                   baseReply->attribute( QNetworkRequest::BackgroundRequestAttribute ) );
-    setAttribute( QNetworkRequest::SpdyWasUsedAttribute,
-                  baseReply->attribute( QNetworkRequest::SpdyWasUsedAttribute ) );
+    setAttribute( QNetworkRequest::Http2WasUsedAttribute,
+                  baseReply->attribute( QNetworkRequest::Http2WasUsedAttribute ) );
 
     emit metaDataChanged();
   }
@@ -133,7 +133,7 @@ using std::string;
   void AllowFrameReply::applyError( QNetworkReply::NetworkError code )
   {
     setError( code, baseReply->errorString() );
-    emit error( code );
+    emit errorOccurred( code );
   }
 
   void AllowFrameReply::readDataFromBase()
@@ -283,7 +283,7 @@ QNetworkReply * ArticleNetworkAccessManager::createRequest( Operation op,
   QNetworkRequest newReq(req);
   if ( hideGoldenDictHeader && req.url().scheme().startsWith("http", Qt::CaseInsensitive))
   {
-    newReq.setRawHeader("User-Agent", req.rawHeader("User-Agent").replace(qApp->applicationName(), ""));
+    newReq.setRawHeader("User-Agent", req.rawHeader("User-Agent").replace(qApp->applicationName().toUtf8(), ""));
   }
 
   QNetworkReply *  reply = QNetworkAccessManager::createRequest( op, newReq, outgoingData );
@@ -336,8 +336,8 @@ sptr< Dictionary::DataRequest > ArticleNetworkAccessManager::getResource(
 
     // See if we have some dictionaries muted
 
-    QSet< QString > mutedDicts =
-        QSet< QString >::fromList( Utils::Url::queryItemValue( url, "muted" ).split( ',' ) );
+    QStringList mutedDictLists=Utils::Url::queryItemValue( url, "muted" ).split( ',' );
+    QSet< QString > mutedDicts ( mutedDictLists.begin(),mutedDictLists.end());
 
     // Unpack contexts
 
@@ -525,7 +525,7 @@ void ArticleResourceReply::readyReadSlot()
 void ArticleResourceReply::finishedSlot()
 {
   if (req->dataSize() < 0) {
-    emit error(ContentNotFoundError);
+    emit errorOccurred(ContentNotFoundError);
     setError(ContentNotFoundError, "content not found");
   }
 
diff --git a/articleview.cc b/articleview.cc
index aa6383e8..57979517 100644
--- a/articleview.cc
+++ b/articleview.cc
@@ -856,15 +856,17 @@ bool ArticleView::eventFilter( QObject * obj, QEvent * ev )
         int delta = result == Gestures::SWIPE_UP ? -120 : 120;
         QWidget *widget = static_cast< QWidget * >( obj );
 
+        QPoint angleDelta(0, delta);
+        QPoint pixelDetal;
         QWidget *child = widget->childAt( widget->mapFromGlobal( pt ) );
         if( child )
         {
-          QWheelEvent whev( child->mapFromGlobal( pt ), pt, delta, Qt::NoButton, Qt::NoModifier );
+          QWheelEvent whev( child->mapFromGlobal( pt ), pt,  pixelDetal,angleDelta, Qt::NoButton, Qt::NoModifier,Qt::NoScrollPhase,false);
           qApp->sendEvent( child, &whev );
         }
         else
         {
-          QWheelEvent whev( widget->mapFromGlobal( pt ), pt, delta, Qt::NoButton, Qt::NoModifier );
+          QWheelEvent whev( widget->mapFromGlobal( pt ), pt,pixelDetal, angleDelta,Qt::NoButton, Qt::NoModifier,Qt::NoScrollPhase,false );
           qApp->sendEvent( widget, &whev );
         }
       }
diff --git a/articlewebview.cc b/articlewebview.cc
index 126f2890..392d4b01 100644
--- a/articlewebview.cc
+++ b/articlewebview.cc
@@ -98,7 +98,7 @@ bool ArticleWebView::eventFilter(QObject *obj, QEvent *ev) {
 
 void ArticleWebView::mousePressEvent(QMouseEvent *event)
 {
-    if (event->buttons() & Qt::MidButton)
+    if (event->buttons() & Qt::MiddleButton)
         midButtonPressed = true;
 }
 
@@ -127,7 +127,7 @@ void ArticleWebView::sendCustomMouseEvent( QEvent::Type type) {
 }
 
 void ArticleWebView::mouseReleaseEvent(QMouseEvent *event) {
-  bool noMidButton = !( event->buttons() & Qt::MidButton );
+  bool noMidButton = !( event->buttons() & Qt::MiddleButton );
 
   if ( midButtonPressed & noMidButton )
     midButtonPressed = false;
@@ -169,7 +169,7 @@ void ArticleWebView::wheelEvent( QWheelEvent *ev )
     SystemParametersInfo( SPI_GETWHEELSCROLLLINES, 0, &nLines, 0 );
     if( nLines == WHEEL_PAGESCROLL )
     {
-      QKeyEvent kev( QEvent::KeyPress, ev->delta() > 0 ? Qt::Key_PageUp : Qt::Key_PageDown,
+      QKeyEvent kev( QEvent::KeyPress, ev->angleDelta ().y () > 0 ? Qt::Key_PageUp : Qt::Key_PageDown,
                      Qt::NoModifier );
       auto childrens = this->children();
       for (auto child : childrens) {
diff --git a/btreeidx.cc b/btreeidx.cc
index ab6dfc93..9fc70a0e 100644
--- a/btreeidx.cc
+++ b/btreeidx.cc
@@ -1437,16 +1437,17 @@ void BtreeIndex::getHeadwordsFromOffsets( QList<uint32_t> & offsets,
 
     for( unsigned i = 0; i < result.size(); i++ )
     {
-      QList< uint32_t >::Iterator it = qBinaryFind( begOffsets, endOffsets,
-                                                    result.at( i ).articleOffset );
+      uint32_t articleOffset =   result.at(i).articleOffset;
+      QList<uint32_t>::Iterator  it = std::lower_bound( begOffsets, endOffsets,
+                                                    articleOffset );
 
-      if( it != offsets.end() )
+      if( it!=offsets.end())
       {
         if( isCancelled && Utils::AtomicInt::loadAcquire( *isCancelled ) )
           return;
 
         headwords.append(  QString::fromUtf8( ( result[ i ].prefix + result[ i ].word ).c_str() ) );
-        offsets.erase( it );
+        offsets.erase( it);
         begOffsets = offsets.begin();
         endOffsets = offsets.end();
       }
diff --git a/dictionary.cc b/dictionary.cc
index 4a185564..56755c4e 100644
--- a/dictionary.cc
+++ b/dictionary.cc
@@ -487,13 +487,13 @@ bool needToRebuildIndex( vector< string > const & dictionaryFiles,
       ZipFile::SplitZipFile zf( name );
       if( !zf.exists() )
         return true;
-      ts = zf.lastModified().toTime_t();
+      ts = zf.lastModified().toSecsSinceEpoch();
     }
     else
     {
       if ( !fileInfo.exists() )
         return true;
-      ts = fileInfo.lastModified().toTime_t();
+      ts = fileInfo.lastModified().toSecsSinceEpoch();
     }
 
     if ( ts > lastModified )
@@ -505,7 +505,7 @@ bool needToRebuildIndex( vector< string > const & dictionaryFiles,
   if ( !fileInfo.exists() )
     return true;
 
-  return fileInfo.lastModified().toTime_t() < lastModified;
+  return fileInfo.lastModified().toSecsSinceEpoch() < lastModified;
 }
 
 QString generateRandomDictionaryId()
diff --git a/dictionarybar.cc b/dictionarybar.cc
index 74ff65f1..8ad0ad0c 100644
--- a/dictionarybar.cc
+++ b/dictionarybar.cc
@@ -211,7 +211,7 @@ void DictionaryBar::showContextMenu( QContextMenuEvent * event, bool extended )
   {
     QString command( editDictionaryCommand );
     command.replace( "%GDDICT%", "\"" + dictFilename + "\"" );
-    if( !QProcess::startDetached( command ) )
+    if( !QProcess::startDetached( command ,QStringList()) )
       QApplication::beep();
   }
 
diff --git a/epwing.cc b/epwing.cc
index fa61ed53..e3979ec5 100644
--- a/epwing.cc
+++ b/epwing.cc
@@ -957,9 +957,7 @@ vector< sptr< Dictionary::Class > > makeDictionaries(
   vector< sptr< Dictionary::Class > > dictionaries;
 
   vector< string > dictFiles;
-  QByteArray catName;
-  catName += QDir::separator();
-  catName += "catalogs";
+  QByteArray catName = QString("%1catalogs").arg(QDir::separator()).toUtf8();
 
   for( vector< string >::const_iterator i = fileNames.begin(); i != fileNames.end();
        ++i )
diff --git a/epwing_book.cc b/epwing_book.cc
index 18f38298..16d99353 100644
--- a/epwing_book.cc
+++ b/epwing_book.cc
@@ -1732,8 +1732,7 @@ QByteArray EpwingBook::handleReference( EB_Hook_Code code, const unsigned int *
     if( refOpenCount > refCloseCount )
       return QByteArray();
 
-    QString str;
-    str.sprintf( "<R%i>", refOpenCount );
+    QString str=QString( "<R%1>").arg( refOpenCount );
     refOpenCount += 1;
     return str.toUtf8();
   }
@@ -1747,7 +1746,7 @@ QByteArray EpwingBook::handleReference( EB_Hook_Code code, const unsigned int *
   refOffsets.append( argv[ 2 ] );
 
   QString str;
-  str.sprintf( "</R%i>", refCloseCount );
+  str.asprintf( "</R%i>", refCloseCount );
   refCloseCount += 1;
 
   return str.toUtf8();
diff --git a/extlineedit.cc b/extlineedit.cc
index ecaa7bda..e2ba7de3 100644
--- a/extlineedit.cc
+++ b/extlineedit.cc
@@ -110,14 +110,12 @@ void ExtLineEdit::updateButtonPositions()
             iconPos = (iconPos == Left ? Right : Left);
 
         if (iconPos == ExtLineEdit::Right) {
-            int right;
-            getTextMargins(0, 0, &right, 0);
-            const int iconoffset = right + 4;
+            QMargins qm=textMargins();
+            const int iconoffset = qm.right() + 4;
             iconButtons[i]->setGeometry(contentRect.adjusted(width() - iconoffset, 0, 0, 0));
         } else {
-            int left;
-            getTextMargins(&left, 0, 0, 0);
-            const int iconoffset = left + 4;
+            QMargins qm=textMargins();
+            const int iconoffset = qm.left() + 4;
             iconButtons[i]->setGeometry(contentRect.adjusted(0, 0, -width() + iconoffset, 0));
         }
     }
diff --git a/favoritespanewidget.cc b/favoritespanewidget.cc
index 392b4156..bb8cf343 100644
--- a/favoritespanewidget.cc
+++ b/favoritespanewidget.cc
@@ -907,7 +907,9 @@ void FavoritesModel::removeItemsForIndexes( const QModelIndexList & idxList )
   for( int i = lowestLevel; i >= 0; i-- )
   {
     QModelIndexList idxSublist = itemsToDelete[ i ];
-    std::sort( idxSublist.begin(), idxSublist.end(), qGreater< QModelIndex >() );
+    //std::greater does not work ,operator < not implemented ,use std:less first ,then std::reverse.
+    std::sort(idxSublist.begin(), idxSublist.end(), std::less<QModelIndex>());
+    std::reverse(idxSublist.begin(), idxSublist.end());
 
     it = idxSublist.begin();
     for( ; it != idxSublist.end(); ++it )
diff --git a/fulltextsearch.cc b/fulltextsearch.cc
index a7ad4595..02b24dce 100644
--- a/fulltextsearch.cc
+++ b/fulltextsearch.cc
@@ -17,6 +17,7 @@
 #include "initializing.hh"
 #include <qt_windows.h>
 #include <uxtheme.h>
+#include <QOperatingSystemVersion>
 
 #endif
 
@@ -248,8 +249,7 @@ FullTextSearchDialog::FullTextSearchDialog( QWidget * parent,
 
   oldBarStyle = 0;
 
-  if( QSysInfo::windowsVersion() >= QSysInfo::WV_VISTA
-      && ( QSysInfo::windowsVersion() & QSysInfo::WV_NT_based )
+  if(  QOperatingSystemVersion::current () >= QOperatingSystemVersion::Windows7
       && !IsThemeActive() )
   {
     QStyle * barStyle = WindowsStyle::instance().getStyle();
@@ -649,7 +649,7 @@ Q_UNUSED( parent );
 
   for( int x = 0; x < hws.length(); x++ )
   {
-    QList< FtsHeadword >::iterator it = qBinaryFind( headwords.begin(), headwords.end(), hws.at( x ) );
+    QList< FtsHeadword >::iterator it = std::lower_bound( headwords.begin(), headwords.end(), hws.at( x ) );
     if( it != headwords.end() )
     {
       it->dictIDs.push_back( hws.at( x ).dictIDs.front() );
diff --git a/gddebug.cc b/gddebug.cc
index 57cd7ab1..7c08f5c0 100644
--- a/gddebug.cc
+++ b/gddebug.cc
@@ -23,7 +23,7 @@ QTextCodec *localeCodec = 0;
     QTextCodec::setCodecForLocale( utf8Codec );
   }
 
-  qWarning( "%s", QString().vsprintf( msg, ap ).toUtf8().data() );
+  qWarning( "%s", QString().vasprintf( msg, ap ).toUtf8().data() );
 
   if( logFilePtr && logFilePtr->isOpen() )
   {
@@ -48,7 +48,7 @@ QTextCodec *localeCodec = 0;
     QTextCodec::setCodecForLocale( utf8Codec );
   }
 
-  qDebug( "%s", QString().vsprintf( msg, ap ).toUtf8().data() );
+  qDebug( "%s", QString().vasprintf( msg, ap ).toUtf8().data() );
 
   if( logFilePtr && logFilePtr->isOpen() )
   {
diff --git a/goldendict.pro b/goldendict.pro
index 04530b7e..9e3d8ec3 100644
--- a/goldendict.pro
+++ b/goldendict.pro
@@ -29,6 +29,8 @@ QT += widgets \
       printsupport \
       help
 
+DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x050F00
+
 # QMediaPlayer is not available in Qt4.
 !CONFIG( no_qtmultimedia_player ) {
   QT += multimedia
diff --git a/groups_widgets.cc b/groups_widgets.cc
index ef9079a4..851b6ba4 100644
--- a/groups_widgets.cc
+++ b/groups_widgets.cc
@@ -744,8 +744,8 @@ void DictGroupsWidget::addAutoGroups()
     dictMap[ name ] = vd;
   }
 
-  QStringList groupList = dictMap.uniqueKeys();
-  QStringList morphoList = morphoMap.uniqueKeys();
+  QStringList groupList = dictMap.keys();
+  QStringList morphoList = morphoMap.keys();
 
   // Insert morphology dictionaries into corresponding lists
 
diff --git a/helpwindow.cc b/helpwindow.cc
index 9652fb7f..8630afcb 100644
--- a/helpwindow.cc
+++ b/helpwindow.cc
@@ -11,6 +11,7 @@
 
 #include "helpwindow.hh"
 #include "gddebug.hh"
+#include <QHelpLink>
 
 namespace Help {
 
@@ -25,9 +26,11 @@ void HelpBrowser::showHelpForKeyword( QString const & id )
 {
   if ( helpEngine )
   {
-    QMap< QString, QUrl > links = helpEngine->linksForIdentifier( id );
-    if( !links.isEmpty() )
-      setSource( links.constBegin().value() );
+    QList<QHelpLink> links = helpEngine->documentsForIdentifier(id);
+    if (!links.isEmpty()) {
+      QHelpLink link=links.constFirst();
+      setSource(link.url);
+    }
   }
 }
 
diff --git a/hotkeyedit.cc b/hotkeyedit.cc
index cf255dde..6ba4f27d 100644
--- a/hotkeyedit.cc
+++ b/hotkeyedit.cc
@@ -87,7 +87,7 @@ void HotKeyEdit::keyPressEvent( QKeyEvent * event )
         // Delete current combo
         currentKey1 = 0;
         currentKey2 = 0;
-        currentModifiers = 0;
+        currentModifiers = Qt::NoModifier;
         continuingCombo = false;
       }
       else
diff --git a/initializing.cc b/initializing.cc
index e6d68b4f..8d1d4a81 100644
--- a/initializing.cc
+++ b/initializing.cc
@@ -8,6 +8,7 @@
 #if defined( Q_OS_WIN32 )
 #include <qt_windows.h>
 #include <uxtheme.h>
+#include <QOperatingSystemVersion>
 
 WindowsStyle::WindowsStyle()
 {
@@ -41,8 +42,7 @@ Initializing::Initializing( QWidget * parent, bool showOnStartup ): QDialog( par
 
   oldBarStyle = 0;
 
-  if( QSysInfo::windowsVersion() >= QSysInfo::WV_VISTA
-      && ( QSysInfo::windowsVersion() & QSysInfo::WV_NT_based )
+  if( QOperatingSystemVersion::current () >= QOperatingSystemVersion::Windows7
       && !IsThemeActive() )
   {
     QStyle * barStyle = WindowsStyle::instance().getStyle();
diff --git a/mainstatusbar.cc b/mainstatusbar.cc
index fe41655b..47ea5f22 100644
--- a/mainstatusbar.cc
+++ b/mainstatusbar.cc
@@ -43,7 +43,7 @@ MainStatusBar::MainStatusBar( QWidget *parent ) : QWidget( parent )
 
 bool MainStatusBar::hasImage() const
 {
-  return !picWidget->pixmap()->isNull();
+  return !picWidget->pixmap().isNull();
 }
 
 void MainStatusBar::clearMessage()
@@ -92,7 +92,7 @@ void MainStatusBar::refresh()
   {
     adjustSize();
 
-    if ( !picWidget->pixmap()->isNull() )
+    if ( !picWidget->pixmap().isNull() )
     {
       picWidget->setFixedSize( textWidget->height(), textWidget->height() );
     }
diff --git a/maintabwidget.cc b/maintabwidget.cc
index fdf3ca15..0d15f9d1 100644
--- a/maintabwidget.cc
+++ b/maintabwidget.cc
@@ -67,7 +67,7 @@ bool MainTabWidget::eventFilter( QObject * obj, QEvent * ev )
   if( obj == tabBar() && ev->type() == QEvent::MouseButtonPress )
   {
      QMouseEvent * mev = static_cast< QMouseEvent *>( ev );
-     if( mev->button() == Qt::MidButton )
+     if( mev->button() == Qt::MiddleButton )
      {
          emit tabCloseRequested( tabBar()->tabAt( mev->pos() ) );
          return true;
diff --git a/mainwindow.cc b/mainwindow.cc
index e5208bf3..c584e16d 100644
--- a/mainwindow.cc
+++ b/mainwindow.cc
@@ -741,7 +741,7 @@ MainWindow::MainWindow( Config::Class & cfg_ ):
 #ifdef Q_OS_WIN
   if( cfg.normalMainWindowGeometry.width() <= 0 )
   {
-    QRect r = QApplication::desktop()->availableGeometry();
+    QRect r = QGuiApplication::primaryScreen ()->geometry ();
     cfg.normalMainWindowGeometry.setRect( r.width() / 4, r.height() / 4, r.width() / 2, r.height() / 2 );
   }
   if( cfg.maximizedMainWindowGeometry.width() > 0 )
@@ -975,7 +975,7 @@ void MainWindow::mousePressEvent( QMouseEvent *event)
     return;
   }
 
-  if (event->button() != Qt::MidButton)
+  if (event->button() != Qt::MiddleButton)
     return QMainWindow::mousePressEvent(event);
 
   // middle clicked
@@ -1194,11 +1194,11 @@ void MainWindow::wheelEvent( QWheelEvent *ev )
 {
   if ( ev->modifiers().testFlag( Qt::ControlModifier ) )
   {
-    if ( ev->delta() > 0 )
+    if ( ev->angleDelta().y() > 0 )
     {
         zoomin();
     }
-    else if ( ev->delta() < 0 )
+    else if ( ev->angleDelta().y()  < 0 )
     {
         zoomout();
     }
@@ -4363,12 +4363,11 @@ void MainWindow::editDictionary( Dictionary::Class * dict )
       QString headword = unescapeTabHeader( ui.tabWidget->tabText( ui.tabWidget->currentIndex() ) );
       command.replace( "%GDWORD%", headword );
     }
-    if( !QProcess::startDetached( command ) )
+    if( !QProcess::startDetached( command,QStringList() ) )
       QApplication::beep();
   }
 }
 
-
 void MainWindow::openDictionaryFolder( const QString & id )
 {
   for( unsigned x = 0; x < dictionaries.size(); x++ )
diff --git a/mainwindow.hh b/mainwindow.hh
index c61f3c83..37b25198 100644
--- a/mainwindow.hh
+++ b/mainwindow.hh
@@ -524,7 +524,7 @@ class ArticleSaveProgressDialog : public QProgressDialog
 Q_OBJECT
 
 public:
-  explicit ArticleSaveProgressDialog( QWidget * parent = 0,  Qt::WindowFlags f = 0 ):
+  explicit ArticleSaveProgressDialog( QWidget * parent = 0,  Qt::WindowFlags f = Qt::Widget ):
     QProgressDialog( parent, f )
   {
     setAutoReset( false );
diff --git a/mdictparser.cc b/mdictparser.cc
index ca044e70..ca0ae455 100644
--- a/mdictparser.cc
+++ b/mdictparser.cc
@@ -357,7 +357,7 @@ bool MdictParser::readHeader( QDataStream & in )
   if ( headerAttributes.contains( "StyleSheet" ) )
   {
     QString styleSheets = headerAttributes.namedItem( "StyleSheet" ).toAttr().value();
-    QStringList lines = styleSheets.split( QRegularExpression( "[\r\n]" ), QString::KeepEmptyParts );
+    QStringList lines = styleSheets.split( QRegularExpression( "[\r\n]" ), Qt::KeepEmptyParts );
 
     for ( int i = 0; i < lines.size() - 3; i += 3 )
     {
diff --git a/preferences.cc b/preferences.cc
index 6be59a98..e3c53a4c 100644
--- a/preferences.cc
+++ b/preferences.cc
@@ -77,7 +77,7 @@ Preferences::Preferences( QWidget * parent, Config::Class & cfg_ ):
     if ( lang == "qt" )
       continue; // We skip qt's own localizations
 
-    sortedLocs.insertMulti(
+    sortedLocs.insert(
       Language::localizedNameForId( LangCoder::code2toInt( lang.toLatin1().data() ) ),
       QPair< QIcon, QString >(
         QIcon( QString( ":/flags/%1.png" ).arg( i->mid( 3, 2 ).toLower() ) ),
@@ -122,7 +122,7 @@ Preferences::Preferences( QWidget * parent, Config::Class & cfg_ ):
         reg = lang.toUpper();
     }
 
-    sortedHelps.insertMulti(
+    sortedHelps.insert(
       Language::localizedNameForId( LangCoder::code2toInt( lang.toLatin1().data() ) ),
       QPair< QIcon, QString >(
         QIcon( QString( ":/flags/%1.png" ).arg( reg.toLower() ) ), lang + "_" + reg ) );
diff --git a/scanflag.cc b/scanflag.cc
index 346f45ce..13982b42 100644
--- a/scanflag.cc
+++ b/scanflag.cc
@@ -3,6 +3,7 @@
 
 #include "scanflag.hh"
 #include "ui_scanflag.h"
+#include <QScreen>
 
 static Qt::WindowFlags popupWindowFlags =
 
@@ -53,7 +54,7 @@ void ScanFlag::showScanFlag()
 
   QPoint currentPos = QCursor::pos();
 
-  QRect desktop = QApplication::desktop()->screenGeometry();
+  QRect desktop = QGuiApplication::primaryScreen()->geometry();
 
   QSize windowSize = geometry().size();
 
diff --git a/scanpopup.cc b/scanpopup.cc
index e61fd4f9..d958a26d 100644
--- a/scanpopup.cc
+++ b/scanpopup.cc
@@ -625,7 +625,7 @@ void ScanPopup::engagePopup( bool forcePopup, bool giveFocus )
 
       QPoint currentPos = QCursor::pos();
 
-      QRect desktop = QApplication::desktop()->screenGeometry();
+      QRect desktop = QGuiApplication::primaryScreen()->geometry();
 
       QSize windowSize = geometry().size();
 
diff --git a/slob.cc b/slob.cc
index 8420f642..fe53be06 100644
--- a/slob.cc
+++ b/slob.cc
@@ -902,7 +902,7 @@ string SlobDictionary::convert( const string & in, RefEntry const & entry )
           || list[ 1 ].endsWith( " tex" ) )
       {
         QString name;
-        name.sprintf( "%04X%04X%04X.gif", entry.itemIndex, entry.binIndex, texCount );
+        name.asprintf( "%04X%04X%04X.gif", entry.itemIndex, entry.binIndex, texCount );
         imgName = texCachePath + "/" + name;
 
         if( !QFileInfo( imgName ).exists() )
@@ -985,7 +985,7 @@ string SlobDictionary::convert( const string & in, RefEntry const & entry )
 
           QString command = texCgiPath + " -e " +  imgName
                             + " \"" + tex + "\"";
-          QProcess::execute( command );
+          QProcess::execute( command,QStringList() );
         }
 
         QString tag = QString( "<img class=\"imgtex\" src=\"file://" )
diff --git a/sources.cc b/sources.cc
index 60558408..a90e2042 100644
--- a/sources.cc
+++ b/sources.cc
@@ -74,7 +74,7 @@ Sources::Sources( QWidget * parent, Config::Class const & cfg):
   ui.programs->resizeColumnToContents( 0 );
   // Make sure this thing will be large enough
   ui.programs->setColumnWidth( 1,
-    QFontMetrics( QFont() ).width(
+    QFontMetrics( QFont() ).horizontalAdvance(
       ProgramTypeEditor::getNameForType( Config::Program::PrefixMatch ) ) + 16 );
   ui.programs->resizeColumnToContents( 2 );
   ui.programs->resizeColumnToContents( 3 );
diff --git a/translatebox.cc b/translatebox.cc
index 67944754..521e973e 100644
--- a/translatebox.cc
+++ b/translatebox.cc
@@ -107,7 +107,7 @@ TranslateBox::TranslateBox(QWidget *parent) : QWidget(parent),
 
   QHBoxLayout *layout = new QHBoxLayout(this);
   setLayout(layout);
-  layout->setMargin(0);
+  layout->setContentsMargins(0,0,0,0);
   layout->addWidget(translate_line);
 
   QPixmap image(":/icons/system-search.svg");
diff --git a/website.cc b/website.cc
index 5167c55f..57431950 100644
--- a/website.cc
+++ b/website.cc
@@ -369,7 +369,7 @@ sptr< DataRequest > WebSiteDictionary::getArticle( wstring const & str,
     {
       codec = QTextCodec::codecForName( QString( "ISO 8859-%1" ).arg( x ).toLatin1() );
       if( codec )
-        urlString.replace( QString( "%25GDISO%1%25" ).arg( x ), codec->fromUnicode( inputWord ).toPercentEncoding() );
+        urlString.replace( QString( "%25GDISO%1%25" ).arg( x ).toUtf8(), codec->fromUnicode( inputWord ).toPercentEncoding() );
 
       if ( x == 10 )
         x = 12; // Skip encodings 11..12, they don't exist
diff --git a/zipfile.cc b/zipfile.cc
index 837eb497..04a43b0c 100644
--- a/zipfile.cc
+++ b/zipfile.cc
@@ -242,11 +242,11 @@ QDateTime SplitZipFile::lastModified() const
   unsigned long ts = 0;
   for( QVector< QFile * >::const_iterator i = files.begin(); i != files.end(); ++i )
   {
-    unsigned long t = QFileInfo( (*i)->fileName() ).lastModified().toTime_t();
+    unsigned long t = QFileInfo( (*i)->fileName() ).lastModified().toSecsSinceEpoch();
     if( t > ts )
       ts = t;
   }
-  return QDateTime::fromTime_t( ts );
+  return QDateTime::fromSecsSinceEpoch( ts );
 }
 
 qint64 SplitZipFile::calcAbsoluteOffset( qint64 offset, quint16 partNo )