The IDLitOperation::UndoOperation function method is called by the iTool system when the user requests the un-execution of an operation (usually by selecting Undo from the iTool Edit menu or toolbar).
An operation based on the IDLitOperation class must implement this method. See Creating an Operation for details.
If you are creating an operation that acts directly on the data that underlies a visualization, consider using the IDLitDataOperation class rather than the IDLitOperation class. IDLitDataOperation provides additional automation of the Undo and Redo mechanisms.
If this method is implemented for an operation, it should do the following:
- Retrieve the IDLitCommand objects from the IDLitCommandSet object passed as the first argument,
- For each IDLitCommand object, retrieve the target of the operation, using the TARGET_IDENTIFIER property,
- Retrieve the stored information and use it to undo the operation,
- Return 1 for success.
Result = Obj->[IDLitOperation::]UndoOperation(CommandSet)
The return value is 1 if the operation was undone successfully, or zero otherwise.
An IDLitCommandSet object that contains all the IDLitCommand objects that were stored during the original execution of the operation.
IDLitOperation::RecordFinalValues, IDLitOperation::RecordInitialValues, IDLitOperation::RedoOperation