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Base classes

Classes that can be used without definition are called base classes. DJ offers the following base classes:

       Arc Button Circle Label Line Oval Rectangle 
       RoundRectangle Polygon Square Star TextArea 
       TextField  Triangle
All these classes have the following attributes: Besides the common attributes, each class also has some specific attributes. For example, the Line class has four integer attributes x1, y1, x2, and y2 that specify the starting and ending points of line components. For the classes Arc, Circle, Rectangle, Square, RoundRectangle, etc., there is a Boolean attribute called fill that specifies whether or not the graphical components are filled. For components with a text, there are attributes for specifying the font used for the textgif. See Appendix I for the structures of the base classes.                            



Neng-Fa ZHOU
Sat Apr 18 16:14:29 JST 1998