Determination of properties to control the read-only mode

I'm a newbie in qt. And i started to read the book. In which i found out the following code.

Code:

---

class MyClass : public QObject {
Q_OBJECT
Q_PROPERTY(bool readOnly READ isReadOnly WRITE setReadOnly)
private:
 bool m_bReadOnly;
public:
 MyClass(QObject* pobj = 0) : QObject(pobj)
 , m_bReadOnly(false)
 {
 }
public:
 void setReadOnly(bool bReadOnly)
 {
 m_bReadOnly = bReadOnly;
 }
 bool isReadOnly() const
 {
 return m_bReadOnly;
 }
}

---

This code about "Determination of properties to control the read-only mode".
But i didn't understand it. And if someone know something about it. Plz,write down your answer. And where do i have to write this code in which file?

Maybe you should first explain what you don't understand?

Declaration of the property? Any part of the implementation for the property? Usage of the property?

Cheers,
_