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Overview of the SCEC Framework
This topic describes the major components of the Siebel Handheld CE (SHCE) COM Extension Framework.
An SHCE COM Extension Component (SCEC) is part of the Siebel Handheld application architecture. One or more SCECs can subscribe to event notifications on Siebel objects, including applets, business components, business services, and the application. A SCEC can perform action requests on the Siebel Handheld application to manipulate Siebel objects. SCECs implement an interface derived from ISHCEEvent, which is defined by the COM Extension Framework.
Siebel events are defined as actionable requests triggered by application logic. Externally defined program modules, implemented by the customer, will handle these events. This feature allows customer-defined business logic to extend the application to handle third-party logic and validation. For example, Buscomp::PreWriteRecord will be called before any record is written to the Siebel Server database, thus allowing you to perform early, specialized validation on a particular field.
Siebel action requests are defined as APIs, implemented by the Siebel Handheld architecture, which allow external customer modules to perform standard operations on the Siebel Handheld application. All action request interfaces are derived from the base ISHCEActionReq interface. For example, BusComp::SetFieldValue can be called by a SCEC in order to set a specific value for a Business Component.
Both Siebel objects and SCECs exist within the Siebel process boundary in each layer of the Siebel architecture. For example, COM components can extend the applet functionality in the user interface layer, while on the object manager layer, extension objects can implement specialized logic by interacting with business components, business objects, and services.
The Siebel object and the SCEC maintain references to each other and interact through synchronous method calls. The Siebel object blocks while the SCEC implements custom behavior for the event to which it is subscribed. After the SCEC handles an event, it returns control to the Siebel object. The COM component uses a returned value to specify whether the Siebel object can continue processing the event normally, cancel operations, or return an error.