在QGraphicsItem中将专用槽连接到QAction

时间:2013-07-13 10:54:23

标签: c++ qt

在下一个代码中,我正在尝试向contextMenuEvent添加动作以获取QGraphicsItem

但问题是插槽“resize()”永远不会被调用

void Rect::contextMenuEvent(QGraphicsSceneContextMenuEvent *event)
{
    QMenu * menu = new QMenu();
      QAction *resizeAction = menu->addAction("Resize?");
      connect(resizeAction, SIGNAL(triggered()), this, SLOT(resize()));
      menu->exec(event->screenPos());
      delete menu;

}

编辑:: “Rect”类的头文件

 class Rect:  public QObject,public QGraphicsItem
    {

    public:
        enum { Type = UserType + 4 };
        Rect(int x,int y,QString s,QColor myRectangleColor,
             QGraphicsItem *parent = 0, QGraphicsScene *scene = 0);
        Rect();
        int type() const
        { return Type; }
        QPainterPath shape() const;
        QRectF my_rect;

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

    protected:

        virtual void mouseMoveEvent ( QGraphicsSceneMouseEvent * event )
        virtual void mousePressEvent (QGraphicsSceneMouseEvent * event );
        virtual void mouseReleaseEvent (QGraphicsSceneMouseEvent * event );

        virtual void mouseMoveEvent(QGraphicsSceneDragDropEvent *event);
        virtual void mousePressEvent(QGraphicsSceneDragDropEvent *event);
        virtual bool sceneEventFilter ( QGraphicsItem * watched, QEvent * event ) ;
        virtual void contextMenuEvent(QGraphicsSceneContextMenuEvent *event);


    private:
        private slots:
        void resize();
        void MoveUpFun();
    };

1 个答案:

答案 0 :(得分:2)

我的评论是正确的:您错过了班级中的Q_OBJECT宏。