1. A method for adding additional functionality to a graphical icon for use in a computer program, the method comprising: providing a graphical icon that is displayable on a display device, the graphical icon graphically representing a desired function without functional code for implementing the desired function on a host processor; selecting from a list of functions, a function to associate with the graphical icon, wherein the function is associated with functional code for implementing the desired function on a host processor, the graphical icon and the function, once associated, constructing a control object; determining whether a new input or output is to be added to the graphical icon based upon the function selected from the list of functions; and adding a new input or output to the graphical icon if the act of determining indicates that a new input or output is to be added.