Event action schema

The GUI framework provides different ways of implementing and calling actions. Typically, actions are implemented as functions in a context class assigned to a GUI element. Other actions might be implemented as windows or document (templates) or on any other form.

The event action schema, however, does not focus on implementing actions, but on linking actions with different types of events. The simple case are system defined links between system events and appropriate actions (e.g. action doBeforeClose() , which is linked with the system close event). For these event actions, no specific schema is required.

The situation becomes more complex considering specific actions initiated by user interaction. Usually, users work with pointing devices (e.g. mouse) or keyboard and use visualized actions in form of buttons, tool bars or menu items. Often, several visualizations in an application refer to the same action (e.g. a menu item and a tool bar item). Moreover, invisible event action elements might be defined as short cuts or hidden key combination.

The GUI frame work introduced the concept of an event action in order to allow an abstract definition of the link between action and event, which may appear in different forms within a GUI application. Event actions can be referred to in an application program via the odabagui::ActionItem class.

In order to provide an event action schema, the GUI framework supports the definition of event action controls ( ADK_EventActionControl ). Most GUI elements like buttons, menus or field controls are event action controls. But one may also define sort of abstract event action controls, which might be associated with several GUI elements.

The GUI framework provides a standard event action schema, which consists of a number of default event actions (e.g. EditEntry or DeleteEntry ). GUI elements like field controls are automatically associated with a set of default event actions depending on the control style.