又出错了。

。

main.obj:-1: error: LNK2001: 无法解析的外部符号 "public: virtual struct QMetaObject const * __thiscall MyView::metaObject(void)const " (?metaObject@MyView@@UBEPBUQMetaObject@@XZ)

main.obj:-1: error: LNK2001: 无法解析的外部符号 "public: virtual void * __thiscall MyView::qt_metacast(char const *)" (?

qt_metacast@MyView@@UAEPAXPBD@Z)

main.obj:-1: error: LNK2001: 无法解析的外部符号 "public: virtual int __thiscall MyView::qt_metacall(enum QMetaObject::Call,int,void * *)" (?qt_metacall@MyView@@UAEHW4Call@QMetaObject@@HPAPAX@Z)

debug\myScene.exe:-1: error: LNK1120: 3 个无法解析的外部命令

这些错都是什么啊。。

我建立了一个继承自QWidget的类，基类是 QGraphicsView

然后生成了myview.h  自己主动加上了宏Q_OBJECT 所以就报那些错了。

。 原理不懂呀

改完之后，记得清理项目！

myview.h

#ifndef MYVIEW_H

#define MYVIEW_H

#include <QGraphicsView>

class MyView : public QGraphicsView

{

   // Q_OBJECT  仅仅需把这里凝视掉即可了

public:

    explicit MyView(QWidget *parent = 0);

protected:

    void mousePressEvent(QMouseEvent *event);

signals:

public slots:

};

#endif // MYVIEW_H

myview.cpp

#include "myview.h"

#include <QMouseEvent>

#include <QGraphicsItem>

#include <QDebug>

MyView::MyView(QWidget *parent) :

    QGraphicsView(parent)

{

}

void MyView::mousePressEvent(QMouseEvent *event)

{

    QPoint viewPos = event->pos();

    qDebug() <<"viewPos:" << viewPos;

    QPointF scenePos = mapToScene(viewPos);

    qDebug() << "scenePos:" << scenePos;

    QTransform transform;

    QGraphicsItem *item = scene()->itemAt(scenePos,transform);

    if(item)

    {

        QPointF itemPos = item->mapFromScene(scenePos);

        qDebug() << "itemPos:" << itemPos;

    }

}

main.cpp

#include <QApplication>

#include <QGraphicsScene>

#include <QGraphicsRectItem>

#include <QGraphicsItem>

#include <QDebug>

#include <QGraphicsView>

#include "myitem.h"

#include "myitem.cpp"

#include "myview.h"

#include "myview.cpp"

int main(int argc,char *argv[])

{

    QApplication app(argc,argv);

    QGraphicsScene scene;

  //  QGraphicsRectItem * item = new QGraphicsRectItem(0,0,100,100);

    MyItem *item = new MyItem;

    scene.addItem(item);

    item->setPos(10,10);

    QGraphicsRectItem *rectItem = scene.addRect(QRect(0,0,100,100),

                                                QPen(Qt::blue),QBrush(Qt::green));

    rectItem->setPos(20,20);

    MyView view;

    view.setScene(&scene);

    view.setForegroundBrush(QColor(255,255,255,100));

    view.setBackgroundBrush(QPixmap("../myScene/11.jpg"));

    view.show();

    return app.exec();

}