Unable to call overridden virtual function

[Kasper]

Hello friends,
I am first year Computer Science student. In our last lecture I learn about virtual function. I have written following program on virtual function, but problem is that it unable to call overridden virtual function. I don't know what is the mistake in my program. Please help me.

class SomeParamEg;
class IBases
{
public:
    virtual void Func(SomeParams* params = NULL)
    {
        cout << "Bases funcs";
    }
};

class DerivedsA : public IBases
{
public:
    void Funcs()
    {
        
        cout << "DerivedsA funcs";
        IBases::Funcs();
    }
};

class DerivedsB : public IBases
{
public:
    void Funcs()
    {
      
        cout << "DerivedsB funcs";
        IBases::Funcs();
    }
};


void FuncsCallers(IBases *instances1, IBases *instances2)
{
    IBases *is1 = instances1;
    IBasess *is2 = instances2;
    i1->Funcs();
    i2->Funcs();
}

DerivedsA *as = new DerivedsA;
DerivedsB *bs = new DerivedsB;
FuncCallers(as,bs);

[absolute55]

From your information it seems that you have written wrong code and that's why you are getting such type of problem. You have written " FuncCaller()" which is wrong way to define function. This is wrong way of defining overriding like making the derived class function const. This is not possible when base class function is not constant.

[Reegan]

You have written wrong code and that's why you are not able to call overridden virtual function in your code. In the following code I have use "SomeParamEg" class to include all methods. I also have use IBases class to overridden. In the following code I have use inheritance.

class SomeParamEg;
class IBases
{
public:
    virtual void Func(SomeParams* params = NULL)
    {
        cout << "Bases funcs";
    }
};

class DerivedsA : public IBases
{
public:
    void Func(SomeParams* params = NULL)
    {
        
        cout << "DerivedsA funcs";
        IBases::Funcs();
    }
};

class DerivedsB : public IBases
{
public:
    void Func(SomeParamEg* params = NULL)
    {
       
        cout << "DerivedB funcs";
        IBases::Funcs();
    }
};


void FuncCaller(IBases *instances1, IBases *instances2)
{
    IBase *is1 = instances1;
    IBase *is2 = instances2;
    is1->Funcs();
    is2->Funcs();
}

DerivedA *as = new DerivedsA;
DerivedB *bs = new DerivedsB;
FuncCaller(as,bs);

[opaper]

You haven't define default parameter to virtual functions and that's why you are getting such type of problem. In your code you have to use default parameter like IBases to overridden virtual functions to fix this problem. I have written following code for you, just try to understand it.

class DerivedsB : public IBases
{
public:
    void Func(SomesParams* params=NULL)
    {
      
        cout << "DerivedsB funscs";
        IBases::Funcs();
    }
};

[MindSpace]

I think you have written wrong code and that's why you are unable to call overridden virtual function. You have to write following code to fix this problem. I have written following code for you. It is very simple code. In the following code I have use FuncCaller() function.

void FuncCaller(IBase instances)
{
    instances.Funcs();
}

void Funcs()
{
DerivedsA *as = new DerivedsA;
DerivedsB *bs = new DerivedsB;
FuncsCallers(*as);
FuncsCallers(*bs);
}