QT5 视图坐标

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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  只需把这里注释掉就行了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();}

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