thumbnailcache.h Example File

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 #ifndef THUMBNAILCACHE_H
 #define THUMBNAILCACHE_H

 #include <QtCore/qcache.h>
 #include <QtCore/qmutex.h>
 #include <QtCore/qqueue.h>
 #include <QtCore/qthread.h>
 #include <QtCore/qwaitcondition.h>

 class QImage;
 class QPixmap;
 class QUrl;

 class Thumbnail;

 class ThumbnailCache : public QThread
 {
     Q_OBJECT
 public:
     ThumbnailCache(QObject *parent = 0);
     ~ThumbnailCache();

     QPixmap thumbnail(const QUrl &url);

     bool event(QEvent *event);

 signals:
     void thumbnailReady();

 protected:
     void run();

 private:
     QImage loadImage(const QUrl &url) const;
     QString thumbnailPath(const QUrl &url) const;

     QMutex mutex;
     QWaitCondition waitCondition;
     QCache<QUrl, Thumbnail> cache;
     QQueue<QUrl> pendingUrls;
     bool cancelled;
 };

 #endif