How to write a common callback function?

Mr Pang

I have below code,

#include <QCoreApplication>
#include <QDebug>
class Base
{
  public:
    virtual void fun1() = 0;
};
class AAA: public Base
{
public:
    void fun1(){
        qWarning()<<__FUNCTION__<<__LINE__;
    }
};

class BBB: public Base
{
public:
    void fun1(){
        qWarning()<<__FUNCTION__<<__LINE__;
    }
};

typedef void (Base::*fun1)(void);
class CCC
{
public:
    void run(fun1 f){
        f();
    }
};

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

    AAA aaa;
    BBB bbb;
    CCC ccc;
    ccc.run(aaa.fun1); //run AAA::fun1
    ccc.run(bbb.fun1); //run BBB::fun1
    QCoreApplication a(argc, argv);

    return a.exec();
}

My purpose is that CCC::run() can call both AAA::fun1() and BBB::fun1(), but it doesn't compile.
What is wrong?

Thanks!

JKSH

@Mr-Pang said in How to write a common callback function?:

typedef void (Base::*fun1)(void);
class CCC
{
public:
    void run(fun1 f){
        f();
    }
};
...

My purpose is that CCC::run() can call both AAA::fun1() and BBB::fun1()

Base::fun1() is already a virtual method, so you should use C++ polymorphism:

class CCC
{
public:
    void run(Base *b){
        b->fun1();
    }
};

int main(int argc, char *argv[])
{
    AAA aaa;
    BBB bbb;
    CCC ccc;
    ccc.run(&aaa);
    ccc.run(&bbb);
}

it doesn't compile.
What is wrong?

Your compiler error message tells you what is wrong.

Mr Pang

@JKSH
Great! I never thought of it before.