Incomplete type.....?

Hi Forum,

I am using QT Creator 2.1.0 based on 4.7.2 (32 bit) the following code creating an error at build compile time!

ERROR READS : "field printer has incorrect type"

Code:

---

#ifndef IMAGEPREVIEWDIALOG_H
#define IMAGEPREVIEWDIALOG_H
 
#include <QDialog>
#include <QScrollArea>
#include <QLabel>
#include <QGraphicsPixmapItem>
#include <QGraphicsScene>
#include <QGraphicsView>
#include <QPixmap>
#include <QPrinter>
#include <QPrintDialog>
namespace Ui {
    class ImagePreviewDialog;
}
 
class ImagePreviewDialog : public QDialog
{
    Q_OBJECT
 
public:
    ImagePreviewDialog(QString file,  QByteArray *imageData, QWidget *parent = 0);
    ~ImagePreviewDialog();
    bool isFileSupported();
 
public slots:
    void print();
private:
 
     Ui::ImagePreviewDialog *ui;
     QGraphicsScene *scene;
     QPixmap pixmap;
     QGraphicsPixmapItem *pixmapItem;
 
     QPrinter printer;            // This object variable causing problem!!!!!!!!!
 
 
    bool fileSupported;
};
 
#endif // IMAGEPREVIEWDIALOG_H

---

AS you can see the class <QPrinter> included in the header file of this source along with <QPrintDialog>, which seems to enough to get compiling. But throws an error

"field printer has incorrect type"

I wonder some one could shed a light on this ... which include file missing at above in this header file, please?

Thank you in advance.

Shy