c++ call outside class functions

Question

Is there an way for an Inside class to call the Outside class functions directly? Instead of having to check if a boolean is true or not.

Like this:

Inside Class

class Inside {

public:
    Inside()
    {
    }
    ~Inside()
    {
    }

    Update()
    {
        if(buttonpress)
        {
         //call Outside::LoadGame();
        }
    }

}

Outside Class

class Outside {

public:
   Outside();
   ~Outside();
   void LoadGame()
   {
     //Load Game
   }

   Inside* insideObject;

   void Update()
   {
     insideObject->Update();
   }


}

Answer 1

It's not possible for you to do, not without the Inside::Update function having a reference to an Outside object.

The easiest solution is to call Update passing this as argument:

class Inside
{
    ...

    void Update(Outside* outside)
    {
        outside->LoadGame();
    }
};

// ...

void Outside::Update()
{
    inside->Update(this);
}

Another solution is passing this as an argument to the constructor when creating the inside object in the Outside class.

---

However, this couples the two classes very tightly, which can be a sign of bad design. Before you implement this, you should ask yourself "Do I really need this tight coupling? Can there be other ways of solving the problem with better design? And what is the problem I try to solve anyway?"