GtkData abstract base class for objects containing data. The #GtkData object is a very simple object intended to be used as a base class for objects which contain data (i.e. the 'Model' in the object-oriented Model/View/Controller framework). Currently it is not very useful since all it provides is a "disconnect" signal. This signal could be emitted by a #GtkData subclass to notify any 'Views' that they should disconnect from the #GtkData (the 'Model'), possibly just before the #GtkData is destroyed.