The constructor first calls the parent class constructor, which
makes self a Frame.
# - - - M o d e l S e l e c t o r . _ _ i n i t _ _
def __init__ ( self, parent, callback ):
"""Constructor for the ModelSelector compound widget.
"""
#-- 1 --
# [ parent := parent with a new Frame widget added but
# not gridded
# self := that new Frame widget ]
Frame.__init__ ( self, parent, relief=SUNKEN, bd=4 )
Next we store a reference to the callback function, and create
the list that will contain the radiobuttons, and then create and
initialize their associated control variable. Finally, we
create all the widgets—see Section 17.4, “ModelSelector.__createWidgets()”.
#-- 2 --
self.__callback = None
self.__radioList = []
self.__radioVar = IntVar()
self.__radioVar.set(0)
#-- 3 --
# [ self := self with all internal widgets created and
# gridded ]
self.__createWidgets()
#-- 4 --
self.__callback = callback