Re: [gtkmm] Obtaining a pointer to an object

[Christer Palm <palm nogui se>]

Miller, Ryan D wrote:
> Is there a way to obtain a pointer from an object to other objects that 
> have been created by the same parent (without passing the pointers as 
> arguments)?  I need to obtain a reference to an object in order to use 
> sigc::mem_fun to connect a signal to another class.  Both of the classes 
> have the same parent window.  I was looking at the get_toplevel and 
> get_ancestor calls, but I don't think they'll work.  Does anyone have 
> any suggestions or some short example code?

Usually you'd do that by passing a reference to the parent object as a 
constructor argument to the child object, and then have the child object 
ask the parent object for references to other objects. Something like:

class ChildA;
class ChildB;

class Parent
{
    ChildA* child_a;
    ChildB* child_b;

    Parent() {
        child_a = new ChildA(*this);
        child_b = new ChildB(*this);
    }
    ChildB& getB() {
        return *child_b;
    }
};

class ChildA
{
    ChildA(Parent& parent) {
        ChildB& child_b = parent.getB();  // Get reference to sibling
    }
};

--
Christer Palm