QT信号函數和槽函數的基本代碼實作

exampleA.h:

#ifndef EXAMPLEA_H      

#define EXAMPLEA_H      

#endif // EXAMPLEA_H      

#include<QCoreApplication>      

class CExampleA:public QObject      

{      

Q_OBJECT      

public:      

CExampleA(){m_Value=0;}      

void SetValue(int nNewval)      

{      

if(m_Value==nNewval)      

{      

return ;      

}      

m_Value=nNewval;      

emit stateChanged(m_Value);      

}      

signals:      

void stateChanged(int nNewVal);      

private:      

int m_Value;      

};      

exampleb.h:

#ifndef EXAMPLEB_H      

#define EXAMPLEB_H      

#endif // EXAMPLEB_H      

#include<QDebug>      

#include<QCoreApplication>      

class CExampleB:public QObject      

{      

Q_OBJECT      

public:      

CExampleB(){}      

public slots:      

void Function(int nNewValue)      

{      

qDebug()<<"new Values = "<<nNewValue;      

}      

};      

main.cpp:

#include<examplea.h>      

#include<exampleb.h>      

int main()      

{      

CExampleA a;      

CExampleB b;      

QObject::connect(&a,SIGNAL(stateChanged(int)),&b,SLOT(Function(int)));      

a.SetValue(100);      

return 100;      

}