Qt Objects
Critical Qt classes are subclasses of class
QObject.
Qt distinguishes some member functions of these classes,
namely slots, signals and properties. Qt provides means
to enumerate these slots, signals and properties at run time.
Please refer to the Qt documentation on the
Qt object model
for more details.
Instances of these classes are known as Qt objects.
Pointers to Qt objects can be exposed to the Lua interpeter because
Qt variants can contain values of type QObjectPointer
which is a guarded pointer to a Qt object.
Such values have a special treatment:
- A distinct metatable is allocated for each Qt object class.
These metatables are available in the
qtpackage and follow the same inheritance pattern as the Qt object class hierarchy. Classqt.QObjectsits at the top of this hierarchy.
- Slots, signals and properties are automatically
exposed to the Lua interpreter. This is achieved
using the information collected by the Qt precompiler
moc.