Imageclass defines several methods of its own which subclasses of
imageclass either have to implement or pass on to their superclass. The
method IDs for imageclass are defined in <intuition/imageclass.h>.  Each
method requires some parameters.  The MethodID is the only parameter
common to each method.

 IM_DRAW       IM_HITTEST        IM_ERASEFRAME      IM_MOVE 
 IM_ERASE      IM_DRAWFRAME      IM_HITFRAME        IM_FRAMEBOX