Returns whether the #GtkCellArea can respond to
#GtkCellAreaClass.activate(), usually this does not need to be
implemented since the base class takes care of this however it can
be enhanced if the #GtkCellArea subclass can handle activation in
other ways than activating its #GtkCellRenderers.
Returns whether the #GtkCellArea can respond to #GtkCellAreaClass.activate(), usually this does not need to be implemented since the base class takes care of this however it can be enhanced if the #GtkCellArea subclass can handle activation in other ways than activating its #GtkCellRenderers.