Meta-object System

Meta-object System is an extension to C++, part of Qt (toolkit). It is essentially a mechanism that provides two services: Signals and slots and introspection.

Elements

The Meta-object System comprises three elements:

• The QObject class. This is the base class required by any object that wants to take advantage of the Meta-object System.
• The Q_OBJECT macro. It is a set of definitions, especially introspection functions. This macro must appear in the private section of a class definition that declares its own signals and slots or that uses any other service provided by Qt's Meta-object System^[1].
• moc (the Meta-object compiler). It is a tool that parses Q_OBJECT class definitions and makes this information available through C++ functions.

References

1. ^ QObject Class Reference

Bibliography

• Blanchette, Jasmin; Summerfield, Mark (February 14, 2008), C++ GUI Programming with Qt 4 (2nd ed.), Prentice Hall, pp. 752, ISBN 978-0132354165, http://www.informit.com/store/product.aspx?isbn=0132354160