<h2><a name="abstract">Abstract</a></h2> <p> Abstract classes are used as base classes. You cannot create an instance of an abstract class directly - you need to subclass it. In the subclass, you need to overload <i>all</i> of the class's <a href="#purevirtual">pure virtual</a> methods. These are marked as "pure virtual" in these docs, and are also indicated by a " = 0" at the end of the method declaration. </p> <p> If your subclass doesn't overload the pure virtual methods in the abstract base class, you won't be able to create an instance of it. </p> <h2><a name="purevirtual">pure virtual</a></h2> <p> Pure virtual methods are members of an <a href="#abstract">abstract</a> class (they're what makes the class abstract in the first place). Pure virtual methods are nothing more than place holders - there is no code associated with them </p> <h2><a name="variables">variables</a></h2> <p> Class variables can be read and written from Python. Global or static variables are <i>read only</i>. Variables that are "protected" or. "private" in C++ are not implemented. </p> <h2><a name="slots">slots</a></h2> <p> When using TQt or KDE in C++, methods involving connections to slots take 2 arguments: a TQObject 'receiver' and a char* 'slot' name. In Python you only need to provide a single value - the name of a Python callable method or function which will be connected to a signal. The method or function does not need to be in the class where it is reference, and does not have to be in a class at all. There are other options - see the "Signals and Slots" documentation for more information. </p>