Connecting slot for drop event in QGraphicsView

[Ishmael]

How do I connect a dropEvent in a QGraphicsView widget to a slot? Here's a snippet of what I've got so far. This compiles just fine, but it doesn't recognize any drop event.

QGraphicsScene *scene = new QGraphicsScene(this);
QGraphicsView *view = new QGraphicsView(scene);
 
view->setAcceptDrops(true);
connect(view, SIGNAL(dropEvent()), this, SLOT(myDropEvent()));
 
void MainWindow::myDropEvent()
{
   QDebug("here");
}

QGraphicsScene *scene = new QGraphicsScene(this);
QGraphicsView *view = new QGraphicsView(scene);

view->setAcceptDrops(true);
connect(view, SIGNAL(dropEvent()), this, SLOT(myDropEvent()));

void MainWindow::myDropEvent()
{
   QDebug("here");
}

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What I'm trying to do is drag and drop items from outside my application into an empty QGraphicsView (for instance, an icon from the Desktop). Can this be done?

Thanks!

[Lykurg]

QGraphicsScene::dropEvent() is not a signal! You have to reimplement:

class YourClass
{
  //...
  dropEvent ( QDropEvent * event );
}
 
 
YourClass::dropEvent ( QDropEvent * event )
{
  QDebug("here");
 
}

class YourClass
{
  //...
  dropEvent ( QDropEvent * event );
}


YourClass::dropEvent ( QDropEvent * event )
{
  QDebug("here");

}

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[Ishmael]

Thanks for your response. Unfortunately, still no luck. I thought making my own class would do the trick.

Here's a sample version of my code. For some reason, it still does not respond to Drop events. I am trying to drag an icon from my desktop onto my GraphicsView window.

Any help you can give me would be greatly appreciated!

Also, I have two questions:
1) What is the difference between QDropEvent and QGraphicsSceneDragDropEvent?
2) As I understand it, I only need to include Q_OBJECT if I want to use signals, is that correct?

(For some reason, when I uncomment Q_OBJECT in my code, I get a bunch of "undefined reference to `vtable for MyGraphicsView'" errors.)

#include <QtGui/QApplication>
#include <QMainWindow>
#include <QGraphicsView>
#include <QDropEvent>
 
class MyGraphicsView : public QGraphicsView
{
    //Q_OBJECT  // Do I need Q_OBJECT?
 
public:
    MyGraphicsView(QGraphicsScene *scene);
 
protected:
    //void dropEvent(QGraphicsSceneDragDropEvent *event);
    void dropEvent(QDropEvent *event);
};
 
 
MyGraphicsView::MyGraphicsView(QGraphicsScene *scene)
{
     this->setScene(scene);
}
 
 
void MyGraphicsView::dropEvent(QDropEvent *event)
{
  qDebug("here");
}
 
 
int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    QMainWindow window;
 
    QGraphicsScene *scene = new QGraphicsScene;
    MyGraphicsView *view = new MyGraphicsView(scene);
    view->setAcceptDrops(true);
 
    window.setCentralWidget(view);
    window.resize(640, 480);
    window.setAcceptDrops(true);
    window.show();
 
    return app.exec();
}

#include <QtGui/QApplication>
#include <QMainWindow>
#include <QGraphicsView>
#include <QDropEvent>

class MyGraphicsView : public QGraphicsView
{
    //Q_OBJECT  // Do I need Q_OBJECT?

public:
    MyGraphicsView(QGraphicsScene *scene);

protected:
    //void dropEvent(QGraphicsSceneDragDropEvent *event);
    void dropEvent(QDropEvent *event);
};


MyGraphicsView::MyGraphicsView(QGraphicsScene *scene)
{
     this->setScene(scene);
}


void MyGraphicsView::dropEvent(QDropEvent *event)
{
  qDebug("here");
}


int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    QMainWindow window;

    QGraphicsScene *scene = new QGraphicsScene;
    MyGraphicsView *view = new MyGraphicsView(scene);
    view->setAcceptDrops(true);

    window.setCentralWidget(view);
    window.resize(640, 480);
    window.setAcceptDrops(true);
    window.show();

    return app.exec();
}

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