Question

我想在点击按钮时调用一个函数。按钮的实现在抽象类中。但是当我编译时，我收到了这个错误。

这是基类的.h文件

#ifndef HOME_H
#define HOME_H
#include<QGraphicsScene>
#include <QGraphicsScene>
#include<QPushButton>

class home
{
  Q_OBJECT
public:
  home();

  virtual void set_home_background()=0 ;
  QGraphicsScene *scene3;
  QPushButton *button3;

private slots:
  virtual void startgame1();
};

#endif // HOME_H

这是基类

#include "home.h"
#include<QGraphicsScene>
#include<QGraphicsProxyWidget>
#include "QMessageBox"

home::home()
{

}

void home::set_home_background()
{
  button3 = new QPushButton;
  QObject::connect(button3,SIGNAL(clicked()),this,SLOT(startgame1()));
  QGraphicsProxyWidget *proxy = this->scene3->addWidget(button3);
  button3->setAutoFillBackground(true);
  button3->setIcon(QIcon(":/Images/ng.png"));
  button3->setIconSize(QSize(131,41));
  proxy->setPos(130,430);
  scene3->addItem(proxy);
}

void home::startgame1()
{
  QMessageBox q;
  q.setText("");
  q.exec();
}

我收到此错误

C：\ Users \ User \ Documents \ breakout_final \ home.cpp：16：错误：无匹配函数调用'QObject :: connect（QPushButton *＆amp;，const char *， home *，const char *）' 的QObject ::连接（BUTTON3，SIGNAL（点击（）），对此，SLOT（startgame1（）））;

Answer 1

你的代码中有错误：为了使用Qt信号和插槽，你应该从QObject继承你的类，Q_OBJECT声明本身是不够的：

#include <QObject>

class home : public QObject
{
    Q_OBJECT
public:
    home();


    virtual void set_home_background()=0 ;
     QGraphicsScene *scene3;
     QPushButton *button3;

private slots:
    virtual void startgame1();    
};

不能从抽象类调用按钮信号

1 个答案: