If a standard task is executable, an user interface specific handler (see SAP Gui Handler) for the action is required. In addition, an user interface independent component is needed which builds the bridge between the user interface and the ProProcess task object. This object is called Executor. ProProcess provides the abstract class /PCH/CLA_BPF_TASK_EXEC that must be extended for each standard task. The abstract implementation contains several methods for accessing and setting data within the task.
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For every single task, a protocol and digital signature is either not available, optional or even mandatory. If the status is set to "completed" or "rejected" it validates if the required information is provided. Depending on the used user interface technology and handler, the protocol and/or digital signature must not be validated when the status is set, because the user interface automatically asks the user for the required information outside of the standard task. Therefore, the handler (see SAP Gui Handler) must disable these checks by calling the methods SET_PROTOCOL/SIGNATURE_IS_REQUIRED.
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