remove old qt(<5) code.

articleview.cc

@@ -2418,9 +2418,6 @@ void ArticleView::performFindOperation( bool restart, bool backwards, bool check
 
     if ( ui.searchCaseSensitive->isChecked() )
       f |= QWebEnginePage::FindCaseSensitively;
-#if QT_VERSION >= 0x040600  && QT_VERSION <= 0x050600
-    f |= QWebEnginePage::HighlightAllOccurrences;
-#endif
 
     ui.definition->findText( "", f );
 
@@ -2678,15 +2675,9 @@ void ArticleView::highlightFTSResults()
   if( ftsSearchMatchCase )
     flags |= QWebEnginePage::FindCaseSensitively;
 
-#if QT_VERSION >= 0x040600
- // flags |= QWebEnginePage::HighlightAllOccurrences;
-
   for( int x = 0; x < allMatches.size(); x++ )
     ui.definition->findText( allMatches.at( x ), flags );
 
- // flags &= ~QWebEnginePage::HighlightAllOccurrences;
-#endif
-
   if( !allMatches.isEmpty() )
   {
       ui.definition->findText( allMatches.at( 0 ), flags );

loaddictionaries.cc

@@ -381,10 +381,6 @@ void loadDictionaries( QWidget * parent, bool showInitially,
   set< string > ids;
   std::pair< std::set< string >::iterator, bool > ret;
 
-#if QT_VERSION < QT_VERSION_CHECK(5, 0, 0)
-  QTextCodec::setCodecForCStrings( QTextCodec::codecForName( "UTF8" ) );
-#endif
-
   for( unsigned x = dictionaries.size(); x--; )
   {
     ret = ids.insert( dictionaries[ x ]->getId() );

mainwindow.cc

@@ -599,7 +599,7 @@ MainWindow::MainWindow( Config::Class & cfg_ ):
   connect( ui.menuHistory, SIGNAL( aboutToShow() ),
            this, SLOT( updateHistoryMenu() ) );
 
-#if !defined( HAVE_X11 ) || QT_VERSION < QT_VERSION_CHECK( 5, 0, 0 )
+#if !defined( HAVE_X11 )
   // Show tray icon early so the user would be happy. It won't be functional
   // though until the program inits fully.
   // Do not create dummy tray icon in X. Cause QT5 failed to upgrade systemtray context menu.

scanpopup.cc

@@ -25,7 +25,7 @@ using std::wstring;
 /// in their behavior on those platforms.
 static const Qt::WindowFlags defaultUnpinnedWindowFlags =
 
-#if defined (Q_OS_WIN) || ( defined (Q_OS_MAC) && QT_VERSION < QT_VERSION_CHECK( 5, 3, 0 ) )
+#if defined (Q_OS_WIN)
 Qt::Tool | Qt::FramelessWindowHint | Qt::WindowStaysOnTopHint
 #else
 Qt::Popup

treeview.cc

@@ -7,11 +7,4 @@
 void TreeView::dropEvent( QDropEvent * event )
 {
   QTreeView::dropEvent( event );
-
-#if QT_VERSION < QT_VERSION_CHECK(5, 0, 0)
-  // Qt 4 don't check success of drop operation. Add turnaround.
-
-  if( !event->isAccepted() )
-    event->setDropAction( Qt::IgnoreAction );
-#endif
 }