Description

VMD contains several user interface components, where each component (a UIObject subclass) can separately issue requested (via Command ojects) to have particular actions completed. The UIList class is used to maintain the entire collection of these user interface components. There is one global instance of this class, uiList; all user interface components which are active during a VMD run must register themselves with this list.

UIList is used for two main purposes:

• To provide the names and pointers for all the UIObject's in the program to other parts of the program that need them.
• To perform global operations on all the UIObject's, such as checking for events, resetting the interfaces, and informing the interfaces when a Command is executed.

When a new UIObject is created, it must register itself with the proper UIList. This is done by specifying a pointer to a UIList in the constructor of all subclasses of UIObject. At present, there is no way to `unregister' from the UIList, it is assumed all UIObject's will be used for the duration of the program.