[Qt-interest] invalid use of incomplete type ‘struct QGraphicsSceneDragDropEvent’

[Riccardo Roasio]

Hi,

i'm trying to use the drag and drop functionality of the QGraphicItem class,
but it's giving me this error:

invalid use of incomplete type ‘struct QGraphicsSceneDragDropEvent’

Can anyone help me to solve this problem?

Thanks so much

Riccardo


Here is the small code i'm trying to run:

#ifndef TABLE_H
#define TABLE_H

#include <QGraphicsItem>

 class Table : public QGraphicsItem
 {
 public:
     Table();

     QRectF boundingRect() const;
     QPainterPath shape() const;
     void paint(QPainter *painter, const QStyleOptionGraphicsItem
*option, QWidget *widget);



 protected:
     void dragEnterEvent(QGraphicsSceneDragDropEvent *event);
     void dragLeaveEvent(QGraphicsSceneDragDropEvent *event);
     void dropEvent(QGraphicsSceneDragDropEvent *event);

     bool dragOver;


 private:
     qreal angle;
     int  width;
     int  height;
     int x;
     int y;
     int  diameter;
     bool rounded;
     QColor color;
 };


#endif // TABLE_H


 #include "table.h"

 #include <QGraphicsScene>
 #include <QPainter>
 #include <QStyleOption>

 #include <math.h>

 static const double Pi = 3.14159265358979323846264338327950288419717;
 static double TwoPi = 2.0 * Pi;

 static qreal normalizeAngle(qreal angle)
 {
     while (angle < 0)
         angle += TwoPi;
     while (angle > TwoPi)
         angle -= TwoPi;
     return angle;
 }

 Table::Table()
 {
     angle=0;
     color=qrand() % 256;
     width=200;
     height=100;
     rounded=false;
     diameter=0;
     x=50;
     y=50;

     setAcceptDrops(true);
 }

 QRectF Table::boundingRect() const
 {
     qreal adjust = 0.5;
     return QRectF(-18 - adjust, -22 - adjust,
                   36 + adjust, 60 + adjust);
 }

 QPainterPath Table::shape() const
 {
     QPainterPath path;
     path.addRect(-10, -20, 20, 40);
     return path;
 }

 void Table::paint(QPainter *painter, const QStyleOptionGraphicsItem
*, QWidget *)
 {
     // Draw Table
     painter->setBrush(color);
     painter->drawRect ( x, y, width, height );

 }

 void Table::dragEnterEvent(QGraphicsSceneDragDropEvent *event)
 {
         event->setAccepted(true);
         dragOver = true;
         update();
 }

 void Table::dragLeaveEvent(QGraphicsSceneDragDropEvent *event)
 {
     Q_UNUSED(event);
     dragOver = false;
     update();
 }

 void Table::dropEvent(QGraphicsSceneDragDropEvent *event)
 {
     dragOver = false;
     update();
 }


#include <QtGui/QApplication>
#include <QGraphicsScene>
#include <QGraphicsView>
#include "table.h"
#include <math.h>


int main(int argc, char *argv[])
{
    QApplication application(argc, argv);
    QGraphicsScene scene;
    scene.setSceneRect(0, 0, 1000, 760);
    scene.setItemIndexMethod(QGraphicsScene::NoIndex);

    Table *table = new Table;
    scene.addItem(table);

    QGraphicsView view(&scene);
    view.setRenderHint(QPainter::Antialiasing);
   // view.setBackgroundBrush(QPixmap(":/images/cheese.jpg"));
    view.setCacheMode(QGraphicsView::CacheBackground);
    view.setViewportUpdateMode(QGraphicsView::BoundingRectViewportUpdate);
    view.setDragMode(QGraphicsView::ScrollHandDrag);
    view.setWindowTitle(QT_TRANSLATE_NOOP(QGraphicsView, "Osty"));
    view.resize(1024, 768);
    view.show();

    return application.exec();
}