Question

I have made a console application which does something. It looks like:

class C
    {
    public:
        void print()
        {
            print("something that only class C knows");
        }
    }   
//**************************************    

class B
    {
    public:
        void print()
        {
            print("something that only class B knows");

            for_each(C c)
            {
                c.print();
            }
        }

    private:
        std::vector<C> c_classes;
    }
//**************************************

class A
    {
    public:
        void print()
        {   
            print("something that only class A knows");

            for_each(B b)
            {
                b.print();
            }
        }
    private:
        std::vector<B> b_classes;
    }

And works nice in console, where I can print from everywhere.

The problem appears when I want to port this application to GUI. I need to show everything that classes A, B and C knows. What is the best way to do this?

I thought to make class A return reference to vector of classes B (which returns reference to vector of classes C) and get values from each instance in GUI class.

But I don’t want to make GUI class so much dependent from these classes.

Is there any better way to do this?

Answer 1

Make a common interface Printable that has a pure virtual print() method (possibly returning a string), and have a vector of pointers to this objects somewhere. Have classes A, B and C derive from Printable. So when you want to print the stats of each object, just iterate through this vector and display the output.