Plugs and Navigation Links

Navigation between different views is enabled by plugs. These can be divided into inbound and outbound plugs. While inbound plugs define the possible starting points of a view, the outbound plugs of a view can be used to call a subsequent view. Plugs are part of the controller of a view. They are always assigned to exactly one view.

Since interface views behave exactly the same as views with regard to navigation, the properties described below also apply to interface views.

·         Several views are generally embedded in a Web Dynpro window. Therefore, it is necessary to qualify one view as the view that is displayed first of all when a window is called. This view is assigned the Default property. The subsequent navigation structure is then created using this view.

·         The entering of a view using an inbound plug always causes an event handler method to be called. This is why an event handler method (whose use is optional) is automatically generated for every inbound plug. In this case, the inbound plug itself represents the event to be handled.

 If a view is flagged as the default view in a window, it is not called using the inbound plug.

To navigate from one view to another, each outbound plug from the first view must be linked with an inbound plug of the second view with the help of a navigation link.

·         Exactly one navigation link can originate from one outbound plug, although this can lead to a series of target views. The arrangement of these target views is not qualified, which means that all target views are controlled at the same time.

In contrast, an inbound plug can be controlled by several outbound plugs.

 Information about which plugs are connected with each other is not contained in the individual views. This information is stored separately in navigation.

By implementing the navigation you create a static, potential connection between two views of a Web Dynpro application. You thus define the view sequence for when the Web Dynpro application is executed. You must define a navigation link for each possible view change.