Transaction Listener Interface Class:
class nsITransactionListener : public nsISupports {
public:
virtual nsresult WillDo(nsITransactionManager *aManager, nsITransaction *aTransaction) = 0;
virtual nsresult DidDo(nsITransactionManager *aManager, nsITransaction *aTransaction, nsresult aDoResult) = 0;
virtual nsresult WillUndo(nsITransactionManager *aManager, nsITransaction *aTransaction) = 0;
virtual nsresult DidUndo(nsITransactionManager *aManager, nsITransaction *aTransaction, nsresult aUndoResult) = 0;
virtual nsresult WillRedo(nsITransactionManager *aManager, nsITransaction *aTransaction) = 0;
virtual nsresult DidRedo(nsITransactionManager *aManager, nsITransaction *aTransaction, nsresult aRedoResult) = 0;
virtual nsresult WillBeginBatch(nsITransactionManager *aManager) = 0;
virtual nsresult DidBeginBatch(nsITransactionManager *aManager, nsresult aResult) = 0;
virtual nsresult WillEndBatch(nsITransactionManager *aManager) = 0;
virtual nsresult DidEndBatch(nsITransactionManager *aManager, nsresult aResult) = 0;
virtual nsresult WillMerge(nsITransactionManager *aManager, nsITransaction *aTopTransaction, nsITransaction *aTransactionToMerge) = 0;
virtual nsresult DidMerge(nsITransactionManager *aManager, nsITransaction *aTopTransaction, nsITransaction *aTransactionToMerge, PRBool aDidMerge, nsresult aMergeResult) = 0;
};
Transaction Listener Interface Methods:
nsresult WillDo(nsITransactionManager *aManager, nsITransaction *aTransaction)
Called before a transaction manager calls a transaction's Do() method.
Parameters
aManager - The transaction manager doing the transaction.
aTransaction - The transaction being done.
Return Values
NS_OK should be used to indicate no error, proceed with normal control flow. NS_COMFALSE can be returned by the listener to indicate no error, interrupt normal control flow.
nsresult DidDo(nsITransactionManager *aManager, nsITransaction *aTransaction, nsresult aDoResult)
Called after a transaction manager calls the Do() method of a transaction.
Parameters
aManager the - Transaction manager that did the transaction.
aTransaction - The transaction that was done.
aDoResult - The nsresult returned after doing the transaction.
Return Values
Error status returned by the listener.
nsresult WillUndo(nsITransactionManager *aManager, nsITransaction *aTransaction)
Called before a transaction manager calls the Undo() method of a transaction.
Parameters
aManager - The transaction manager undoing the transaction.
aTransaction - The transaction being undone.
Return Values
Error status returned by the listener. NS_OK should be used to indicate no error, proceed with normal control flow. NS_COMFALSE can be returned by the listener to indicate no error, interrupt normal control flow.
nsresult DidUndo(nsITransactionManager *aManager, nsITransaction *aTransaction, nsresult aUndoResult)
Called after a transaction manager calls the Undo() method of a transaction.
Parameters
aManager - The transaction manager undoing the transaction.
aTransaction - The transaction being undone.
aUndoResult - The nsresult returned after undoing the transaction.
Return Values
Error status returned by the listener.
nsresult WillRedo(nsITransactionManager *aManager, nsITransaction *aTransaction)
Called before a transaction manager calls the Redo() method of a transaction.
Parameters
aManager the transaction manager redoing the transaction.
@param aTransaction the transaction being redone.
Return Values
Error status returned by the listener. NS_OK should be used to indicate no error, proceed with normal control flow. NS_COMFALSE can be returned by the listener to indicate no error, interrupt normal control flow.
nsresult DidRedo(nsITransactionManager *aManager, nsITransaction *aTransaction, nsresult aRedoResult)
Called after a transaction manager calls the Redo() method of a transaction.
Parameters
aManager - The transaction manager redoing the transaction.
aTransaction - The transaction being redone.
aRedoResult - The nsresult returned after redoing the transaction.
Return Values
Error status returned by the listener.
nsresult WillBeginBatch(nsITransactionManager *aManager)
Called before a transaction manager begins a batch.
Parameters
aManager - The transaction manager beginning a batch.
Return Values Error status returned by the listener. NS_OK should be used to indicate no error, proceed with normal control flow. NS_COMFALSE can be returned by the listener to indicate no error, interrupt normal control flow.
nsresult DidBeginBatch(nsITransactionManager *aManager, nsresult aResult)
Called after a transaction manager begins a batch.
Parameters
aManager - The transaction manager that began a batch.
aResult - The nsresult returned after beginning a batch.
Return Values
Error status returned by the listener.
nsresult WillEndBatch(nsITransactionManager *aManager)
Called before a transaction manager ends a batch.
Parameters
aManager - The transaction manager ending a batch.
Return Values
Error status returned by the listener. NS_OK should be used to indicate no error, proceed with normal control flow. NS_COMFALSE can be returned by the listener to indicate no error, interrupt normal control flow.
nsresult DidEndBatch(nsITransactionManager *aManager, nsresult aResult)
Called after a transaction manager ends a batch.
Parameters
aManager - The transaction manager ending a batch.
aResult - The nsresult returned after ending a batch.
Return Values
Error status returned by the listener.
nsresult WillMerge(nsITransactionManager *aManager, nsITransaction *aTopTransaction, nsITransaction *aTransactionToMerge)
Called before a transaction manager tries to merge a transaction, that was just executed, with the transaction at the top of the undo stack.
Parameters
aManager - The transaction manager ending a batch.
aTopTransaction - The transaction at the top of the undo stack.
aTransactionToMerge - The transaction to merge.
Return Values
Error status returned by the listener. NS_OK should be used to indicate no error, proceed with normal control flow. NS_COMFALSE can be returned by the listener to indicate no error, interrupt normal control flow.
nsresult DidMerge(nsITransactionManager *aManager, nsITransaction *aTopTransaction, nsITransaction *aTransactionToMerge, PRBool aDidMerge, nsresult aMergeResult)
Called after a transaction manager tries to merge a transaction, that was just executed, with the transaction at the top of the undo stack.
Parameters
aManager - The transaction manager ending a batch.
aTopTransaction - The transaction at the top of the undo stack.
aTransactionToMerge - The transaction to merge.
aDidMerge - True if transaction was merged, else false.
aMergeResult - The nsresult returned after the merge attempt.
Return Values
Error status returned by the listener. NS_OK should be used to indicate no error, proceed with normal control flow. NS_COMFALSE can be returned by the listener to indicate no error, interrupt normal control flow.