Introduction to Design Patterns in C++ with Qt, 2nd Edition

Chapter 12: Meta Objects, Properties, and Reflective Programming

This chapter introduces the idea of reflection, the self-examination of an object’s members. Using reflective programming, you can write general-purpose operations that work on classes of varied structures. Using QVariant, a generic value-holder, you can operate on built-in types and other common types in a uniform way.

12.1 QMetaObject—The MetaObject Pattern

A meta object is an object that describes the structure of another object.¹

The MetaObject Pattern

QMetaObject is Qt’s implementation of the MetaObject pattern. It provides information about the properties and methods of a QObject. The MetaObject pattern is sometimes known as the Reflection pattern.

A class that has a MetaObject ...