如何在 class Hirarchy 中传递智能指针

Question

So, im trying to figure out, how to pass pointers between objects in a Hirarchy of objects. The actual program im writing is a component based game engine, but i will try to break the problem down as far as possible.

My Current Hirarchy look like this, i have 3 classes, a parent class, that basically governs the lifetime of all child objects, if it gets destructed, everything else will follow:

Parent.h:

    class Parent
    {
    private:
        std::vector<std::shared_ptr<Object>> objects;
    };

A Middle Object, that governs the lifetime of its child objects:

Object.h:

    class Object
    {
    public:
        Parent* parent;

    private:
        std::vector<std::shared_ptr<Child>> childObjects;
    };

And a Child Object:

Child.h:

    class Child
    {
    public:

        std::weak_ptr<Object> parent;
    };

The problem is now, that the Child object needs a reference to its parent object, but all the shared pointers that own the Childs parent object live in the Global Parent and just creating a weak pointer from a pointer to the Childs Parent would not work.

I've come up with two solutions, either passing a plain pointer to the Child and having the child traverse up to the Global parent and get the weak pointer there, which would require finding the pointer to the childs parent in a vector and might not always be possible.

The other solution i have is passing a weak pointer to the childs parent constructor and storing a weak pointer to itself in the childs parent which does seem kinda messy.

Im now asking if theres some better solution i have missed.

Answer 1

Thank you, shared_from_this was exactly what i was looking for.