I want to start by showing some code and explain my problem later.

Base class:

class swcObject :
    public swcRectangle
{
public:
    bool visible;
};

Sub-base class[optional, abstract]:

class swcText
{
public:
    std::string text;
protected:
    virtual void attachedToParent() = 0;
};

Derived classes:

class swcLabel :
    public swcObject,
    public swcText
{
public:
    int text_align;
private:
    void attachedToParent();
};

...

class swcComboBox :
    virtual protected swcObject
{
public:
    void setPosition(int x, int y);
private:
     swcLabel label;
};

Now I have this class w/c has a member object of type std::vector<swcObject>.

class swcWindow :
    private swcObject
{
public:
    void addObject(const swcObject &object);
private:
    std::vector<swcObject> objects;
};

I came into this few problems w/c I haven't encountered before and Google seems don't have a relevant problem like mine.

My specific problems are:

Relevant code:

swcWindow window;
swcComboBox cbox;

window.addObject(cbox);

Error:

'swcObject' is an inaccessible base of 'swcComboBox'

Desire:

I do not want to access swcComboBox::swcObject members on public scope like this cbox.x = 0;, but instead cbox.setPosition(0, 0); because there will be always an adjusting of some member elements whenever the swcComboBox had changed its location.

Relevant code:

swcWindow window;
swcLabel label;

window.addObject(label);

Error:

In this case, label have a base classes of swcText and swcObject. After adding the label to one of member of window.objects (is of type std::vector), swcText properties are gone, like the text property.

Desire:

I want to create a temporary objects and initialize its property in a init() method outside of those classes and copy it using swcWindow::addObject(). Is this possible without a cast? I think this one would do but its awful(?), and I didn't try it yet if this is working:

void addObject(const swcObject &object, SWC_TYPES type)
{
    switch (type)
    {
    case LABEL:
        //do casting?
    ...
    }

}

Please recommend any other way how can I achieve those kind of implementation with the same functionalities.