The QWhatsThis class provides a simple description of any widget, e.g. answering the question "what's this?" ... List of all member functions. void  add  ( QWidget *, const char *, bool deepCopy = TRUE )  . ... void  remove  ( QWidget * )  . ... QWhatsThis provides functions to add () and remove () What's This help for a widget, and it provides a function to create a What's This button suitable for typical tool bars. ... Adds text as What's This help for widget, with title line title and icon icon. ...