How to get a pointer to a QObject's property ?

[HiJack]

Assuming here's a class named QXXX inherited from QObject, how can i get the address of the property ["Abc"], any idea?

class QABC : public QObject
{
Q_OBJECT
    Q_PROPERTY(int Val READ Val WRITE setVal)
public:
    QABC (QObject* parent = 0, int a = 987) : QObject(parent)
    {
        setVal(a);
    }
    ~QABC ()
    {
    }
    QABC (const QABC & rhs)
    {
        copyFrom(rhs);
    }
 
    QABC & copyFrom(const QABC & rhs)
    {
        if(this == &rhs)
            return *this;
 
        setVal(rhs._val);
 
        return *this;
    }
 
    QABC & operator = (const QABC & rhs)
    {
        return copyFrom(rhs);
    }
 
    int Val() const { return _val; }
    void setVal( int val ) { _val = val; }
private:
    int             _val;
};
class QXXX : public QObject
{
Q_OBJECT
    Q_PROPERTY(QABC Abc READ Abc WRITE setAbc)
public:
    QXXX(QObject* parent = 0, QABC a = QABC()) : QObject(parent)
    {
        setAbc(a);
    }
    ~QXXX()
    {
    }
    QXXX(const QXXX& rhs)
    {
        copyFrom(rhs);
    }
 
    QXXX& copyFrom(const QXXX& rhs)
    {
        if(this == &rhs)
            return *this;
 
        setAbc(rhs._Abc);
 
        return *this;
    }
 
    QXXX& operator = (const QXXX& rhs)
    {
        return copyFrom(rhs);
    }
 
    QAbc Abc() const { return _Abc; }
    void setAbc( QAbc val ) { _Abc= val; }
private:
    QABC _Abc;
};

class QABC : public QObject
{
Q_OBJECT
    Q_PROPERTY(int Val READ Val WRITE setVal)
public:
    QABC (QObject* parent = 0, int a = 987) : QObject(parent)
    {
        setVal(a);
    }
    ~QABC ()
    {
    }
    QABC (const QABC & rhs)
    {
        copyFrom(rhs);
    }

    QABC & copyFrom(const QABC & rhs)
    {
        if(this == &rhs)
            return *this;

        setVal(rhs._val);

        return *this;
    }

    QABC & operator = (const QABC & rhs)
    {
        return copyFrom(rhs);
    }

    int Val() const { return _val; }
    void setVal( int val ) { _val = val; }
private:
    int             _val;
};
class QXXX : public QObject
{
Q_OBJECT
    Q_PROPERTY(QABC Abc READ Abc WRITE setAbc)
public:
    QXXX(QObject* parent = 0, QABC a = QABC()) : QObject(parent)
    {
        setAbc(a);
    }
    ~QXXX()
    {
    }
    QXXX(const QXXX& rhs)
    {
        copyFrom(rhs);
    }

    QXXX& copyFrom(const QXXX& rhs)
    {
        if(this == &rhs)
            return *this;

        setAbc(rhs._Abc);

        return *this;
    }

    QXXX& operator = (const QXXX& rhs)
    {
        return copyFrom(rhs);
    }

    QAbc Abc() const { return _Abc; }
    void setAbc( QAbc val ) { _Abc= val; }
private:
    QABC _Abc;
};

To copy to clipboard, switch view to plain text mode 

QXXX x;
...
QObject * z = (QObject*)x;
QObject* pointer = z ...?? ???? // to get (&QXXX::_Abc)
I just only know the property name, it's 'Abc', can i get &z->_Abc?