Define application rules

Application rules are, typically, defined on control or field level. Since a control defines common behavior for a GUI element, the field defines the behavior of a GUI element in a certain context (form or window). Thus, one may associate a control context class defining the behavior for the GUI element with a field, but also with a control.

When a context is defined for the control referenced by the field, but also for the field, the field context class will overload the control context class completely, i.e. control context behavior will not be activated at all. In order to specialize the control context behavior in a field context class, one may define a field context class which inherits from the control context class.

After implementing the handlers and functions required, the context class library has to be created (see Create application rules library (context class library) ), except the class has been implemented as OSI class.