Qt之自定義Item以及鼠標事件測試

一、main.cpp

#include <QApplication>
#include <QGraphicsScene>
#include <QGraphicsView>
#include "myitem.h"
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);


    QGraphicsScene scene(0, 0, 250, 250);

    MyItem *item = new MyItem;
    item->setPos(24, 24);
    scene.addItem(item);

    QGraphicsView view(&scene);

    view.show();

    return a.exec();
}

二、myitem.h

#ifndef MYITEM_H
#define MYITEM_H

#include <QGraphicsItem>
#include <QPainter>
#include <QWidget>
#include <QDebug>
#include <QGraphicsSceneMouseEvent>

class MyItem : public QGraphicsItem
{

public:
    MyItem(QGraphicsItem *parent = 0){}
    ~MyItem(){}

    QRectF boundingRect() const
    {
        return QRectF(0, 0, 200, 200);
    }

    void paint(QPainter *painter,
               const QStyleOptionGraphicsItem *,
               QWidget *)
    {
        painter->setRenderHint(QPainter::Antialiasing);
        painter->setBrush(Qt::blue);

        painter->drawRoundedRect(0, 0, 200, 200, 5, 5);
    }

protected:
    void mousePressEvent(QGraphicsSceneMouseEvent *){
        qDebug("Mouse button clicked");
    }
    void mouseReleaseEvent(QGraphicsSceneMouseEvent *){
         qDebug("Mouse released clicked");
    }
    void mouseMoveEvent(QGraphicsSceneMouseEvent *){
         qDebug("Mouse move");
    }
    void mouseDoubleClickEvent(QGraphicsSceneMouseEvent *){
        qDebug("Mouse double clicked");
    }
};

#endif // MYITEM_H