An Introduction to Design Patterns in C++ with Qt 4

Chapter 9. QObject

An important class to become familiar with is the one from which all Qt Widgets are derived: QObject.

9.1	QObject’s Child Managment	194
9.2	Composite Pattern: Parents and Children	196
9.3	QApplication and the Event Loop	200
9.4	Q_OBJECT and moc: A Checklist	209
9.5	Values and Objects	210
9.6	tr() and Internationalization	211

We will refer to any object of a class derived from QObject as a QObject. Here is an abbreviated look at its definition.

class QObject {
  public:
    QObject(QObject* parent=0);
    QObject * parent () const;
    QString objectName() const;
    void setParent ( QObject * parent );
    const ObjectList & children () const;
    // ... more ...
};

The first interesting thing that we observe is that QObject’s copy constructor is not public. QObjects are ...