LNK2001 error when accessing static variables C++

Question

I\'m trying to use a static variable in my code when trying to use textures, however I keep getting this error:

1>Platform.obj : error LNK2001: unresolved ext         


        

Answer 1

add this:

GLuint Platform::tex_plat;

after your class declaration.

Answer 2

Static member must be defined outside class body, so you have to add the definition and provide initializer there:

class Platform :
public Object
{
    public:
        Platform(void);
        ~Platform(void);
        Platform(GLfloat xCoordIn, GLfloat yCoordIn, GLfloat widthIn);
        void draw();
        static int loadTexture();

    private:
        static GLuint tex_plat;
};

// in your source file
GLuint Platform::tex_plat=0; //initialization

It is also possible to initialize it inside your class but:

To use that in-class initialization syntax, the constant must be a static const of integral or enumeration type initialized by a constant expression.