Classe de base abstraite C++ appelant résultats propre fonction virtuelle pure dans « Undefined reference » - Stack Overflow

I have a base class:

class Foo {
   public:
       virtual ~Foo() {}
       static void printFoos()
       {
           std::vector<Foo*>::iterator it;
           for(it=fooList.begin();it!=fooList.end();++it)
           {
               std::cout<<"Class: "<<(*it)->getClassName()<<"\n";
           }
       }
       virtual const char* getClassName()=0;
       static std::vector<Foo*> fooList;
};

And a few derived classes, example given:

class Bar : public Foo {
    public:
        Bar();
    private:
        const char* getClassName()
        {
            return "Bar";
        }
};

The above code gives "undefined reference to Foo::getClassName()" which Im assuming because the code wants to call Foo::getClassName(), but how do I get it to call the function like a virtual call normally? I.E. How do I get it to call Bar::getClassName() from inside Foo?

EDIT: Forgot inheritance thingy

Items in fooList must be created with new, fooList[0] = new Bar(). And Bar must inherit from Foo, as WeaselFox said.

There are two things that are undefined:

Bar::Bar() is undefined

-   Bar();
+   Bar() {}

and fooList is undefined:

+std::vector<Foo*> Foo::fooList;

Here is corrected program:

test.cpp:

#include <vector>
#include <iostream>

class Foo {
   public:
       virtual ~Foo() {}
       static void printFoos()
       {
           std::vector<Foo*>::iterator it;
           for(it=fooList.begin();it!=fooList.end();++it)
           {
               std::cout<<"Class: "<<(*it)->getClassName()<<"\n";
           }
       }
       virtual const char* getClassName()=0;
       static std::vector<Foo*> fooList;
};

std::vector<Foo*> Foo::fooList;

class Bar : public Foo {
    public:
        Bar() {};
    private:
        const char* getClassName()
        {
            return "Bar";
        }
};

int main()
{
    //intentionally leaked
    Foo::fooList.push_back(new Bar());
    Foo::fooList.push_back(new Bar());
    Foo::fooList.push_back(new Bar());

    Foo::printFoos();
}

output:

Class: Bar
Class: Bar
Class: Bar

It seems bar does not inherit foo. You need to declare inheritance:

class bar: public foo { ...

I have a base class:

class Foo {
   public:
       virtual ~Foo() {}
       static void printFoos()
       {
           std::vector<Foo*>::iterator it;
           for(it=fooList.begin();it!=fooList.end();++it)
           {
               std::cout<<"Class: "<<(*it)->getClassName()<<"\n";
           }
       }
       virtual const char* getClassName()=0;
       static std::vector<Foo*> fooList;
};

And a few derived classes, example given:

class Bar : public Foo {
    public:
        Bar();
    private:
        const char* getClassName()
        {
            return "Bar";
        }
};

The above code gives "undefined reference to Foo::getClassName()" which Im assuming because the code wants to call Foo::getClassName(), but how do I get it to call the function like a virtual call normally? I.E. How do I get it to call Bar::getClassName() from inside Foo?

EDIT: Forgot inheritance thingy

Items in fooList must be created with new, fooList[0] = new Bar(). And Bar must inherit from Foo, as WeaselFox said.

There are two things that are undefined:

Bar::Bar() is undefined

-   Bar();
+   Bar() {}

and fooList is undefined:

+std::vector<Foo*> Foo::fooList;

Here is corrected program:

test.cpp:

#include <vector>
#include <iostream>

class Foo {
   public:
       virtual ~Foo() {}
       static void printFoos()
       {
           std::vector<Foo*>::iterator it;
           for(it=fooList.begin();it!=fooList.end();++it)
           {
               std::cout<<"Class: "<<(*it)->getClassName()<<"\n";
           }
       }
       virtual const char* getClassName()=0;
       static std::vector<Foo*> fooList;
};

std::vector<Foo*> Foo::fooList;

class Bar : public Foo {
    public:
        Bar() {};
    private:
        const char* getClassName()
        {
            return "Bar";
        }
};

int main()
{
    //intentionally leaked
    Foo::fooList.push_back(new Bar());
    Foo::fooList.push_back(new Bar());
    Foo::fooList.push_back(new Bar());

    Foo::printFoos();
}

output:

Class: Bar
Class: Bar
Class: Bar

It seems bar does not inherit foo. You need to declare inheritance:

class bar: public foo { ...

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