Fix some qt6 compile error

cache.h

@@ -21,14 +21,12 @@
 #include <QDataStream>
 #include <QFile>
 #include <QBuffer>
+#include <QVector>
 
 class Playlist;
 class PlaylistCollection;
 class FileHandle;
 
-template<class T>
-class QVector;
-
 typedef QVector<Playlist *> PlaylistList;
 
 /**

deletedialog.h

@@ -17,10 +17,10 @@
 #ifndef JUK_DELETEDIALOG_H
 #define JUK_DELETEDIALOG_H
 
-class QStringList;
 
 #include <QWidget>
 #include <QDialog>
+#include <QStringList>
 
 #include <KGuiItem>
 

filehandle.h

@@ -20,12 +20,12 @@
 #include <QExplicitlySharedDataPointer>
 #include <QVector>
 #include <QMetaType>
+#include <QStringList>
 
 class QString;
 class QFileInfo;
 class QDateTime;
 class QDataStream;
-class QStringList;
 
 class CoverInfo;
 class Tag;

mediafiles.h

@@ -19,10 +19,10 @@
 
 #include <QList>
 #include <QUrl>
+#include <QStringList>
 
 class QWidget;
 class QString;
-class QStringList;
 
 namespace TagLib {
     class File;

playlist.cpp

@@ -56,6 +56,7 @@
 #include <QStackedWidget>
 #include <QScrollBar>
 #include <QPainter>
+#include <QActionGroup>
 
 #include <QtConcurrent>
 #include <QFutureWatcher>

playlistcollection.h

@@ -25,7 +25,7 @@
 
 #include <QPointer>
 #include <QKeySequence>
-
+#include <QVector>
 class QPixmap;
 class QStackedWidget;
 
@@ -40,8 +40,6 @@ class Playlist;
 class PlayerManager;
 class FileHandle;
 
-template<class T>
-class QVector;
 
 typedef QVector<PlaylistItem *> PlaylistItemList;
 typedef QVector<Playlist *> PlaylistList;

treeviewitemplaylist.h

@@ -19,8 +19,7 @@
 
 #include "searchplaylist.h"
 #include "playlistitem.h"
-
-class QStringList;
+#include <QStringList>
 
 class TreeViewItemPlaylist : public SearchPlaylist
 {