Writing a graphical user interface for Mathematica using Mathematica and MathLink

Interactive graphics are a weak part of Mathematica. In this article, a MathLink program which provides interactive graphics in realtime will be introduced. The program can be used to detect a user interface event, and send it to the Mathematica Kernel as an Event Expression. This mechanism enables one to write Graphical User Interface(GUI) in Mathematica. To define a GUI object in Mathematica, an Object Oriented Programming Style (OOPS) is introduced. The combination of realtime interaction and kernel evaluation provides a dynamical interface building, execution, and debugging environment. In this article, the overall design of the program will be discussed.