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About Event Handling

A task event is a type of event that allows you to define the processing that Siebel CRM does when an operation in a task UI calls an event. The following operations support event handling:

• Pause
• Resume
• Cancel
• Delete
• Complete

If Siebel CRM starts an operation in a task UI, then it calls a task event to handle the operation. The event handler for each operation performs the required action according to the semantics of each operation. A preevent handler is a type of handler that runs before Siebel CRM performs the operation for the handler, such as Resume, Pause, or Delete. Most handlers are preevent handlers.

For example, the Cancel operation includes two event handlers: a preevent handler and a postevent handler:

• The PreCancel event handler runs when the user cancels a task UI and before the temporary storage data rolls back.
• The PostCancel event handler starts after the PreCancel event handler runs and after Siebel CRM rolls back the temporary storage after the task finishes. For example, if the user clicks Finish or Submit, then the PostComplete event handler starts.

Siebel CRM does the following work to run an event handler that starts before the user starts the operation:

• If the event handler succeeds, then the task controller finishes the operation that the user started.
• If the event handler fails, then Siebel CRM stops the operation that the user started and returns the error to the object that called the event.

For more information, see Creating a Task Event and Siebel Object Interfaces Reference.

How Siebel CRM Handles an Event That Occurs in a Subtask

You cannot configure a subtask to reference an event handler. If a task UI calls a task event when the user is in a subtask, then Siebel CRM sends the task event to the parent task UI and runs the corresponding event handler that the parent task references. It runs this event handler in the context of the parent task.