... Template class that provides arrays of simple types . ... Internal class, used with QBitArray . ... Lines up child widgets horizontally or vertically . ... The abstract base class of button widgets, providing functionality common to buttons . ... Template class that provides a cache based on char* keys . ... Event parameters for child widget events . ... Base class of all event classes. ... Event parameters for widget focus events . ... The base class of widgets that have an (optional) frame . ...