Hello,
I try to have a context menu in Qt if we do a long press on a QGraphicsItemGroup. I have try basic thing like this:
my .h:
Qt Code: 
  1. class myclass: public QMainWindow
  2. {
  3. 	Q_OBJECT
  4. public:
  5.     myclass(QWidget *parent = 0);
  6.     ~myclass();
  7.  
  8. public slots:
  9.     void contextMenuEvent(QContextMenuEvent *event);
  10.  
  11. private:
  12.     Ui::myclassClass ui;
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my cpp:
Qt Code: 
  1. void myclass::contextMenuEvent(QContextMenuEvent *event)
  2. {
  3.     if (event)
  4.     {
  5.         QMenu *menu = new QMenu;
  6.         menu->addAction(new QAction("Action 1", this));
  7.         menu->addAction(new QAction("Action 2", this));
  8.         menu->addAction(new QAction("Action 3", this));
  9.         menu->exec(event->globalPos());
  10.     }
  11.     }
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It's work, but only with right click. And how to have this only on a QGraphicsItemGroup with a long left click ?