In this section we'll learn about C++ app development comprising of multiple files. We'll develop a class, called Vector, which implements a dynamic array. This class is similar to the std::vector class offered by Standard Template Library (STL) and has a very limited set of features compared to STL class.

Create a new project and name it App2. Navigate to File | New | File… menu option and then choose C/C++ header option and follow the wizard to add a new file to App2 project. Add the following code in a new file under App2 and name it vector.h file:

#ifndef __VECTOR_H__
#define __VECTOR_H__

#ifndef DATA_TYPE
#define DATA_TYPE double
#endif

class Vector {
public:
    Vector(size_t size = 2);
    virtual ~Vector();

    size_t GetCount() const;

    bool Set(size_t id, DATA_TYPE data);
    DATA_TYPE operator[] (size_t id);

private:
    DATA_TYPE* m_data;
    size_t     m_size;
};

#endif //__VECTOR_H__

Header file vector.h declares the Vector class structure....