1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* This Source Code Form is subject to the terms of the Mozilla Public
3 * License, v. 2.0. If a copy of the MPL was not distributed with this
4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6 #include
"nsISupports.idl"
7 #include
"nsITransaction.idl"
8 #include
"nsITransactionList.idl"
9 #include
"nsITransactionListener.idl"
13 #define NS_TRANSACTIONMANAGER_CONTRACTID
"@mozilla.org/transactionmanager;1"
18 * The nsITransactionManager interface.
20 * This interface is implemented by an object that wants to
21 * manage/track transactions.
23 [scriptable
, builtinclass
, uuid(c77763df
-0fb9
-41a8
-8074-8e882f605755
)]
24 interface nsITransactionManager
: nsISupports
27 * Calls a transaction's doTransaction() method, then pushes it on the
30 * This method calls the transaction's AddRef() method.
31 * The transaction's Release() method will be called when the undo or redo
32 * stack is pruned or when the transaction manager is destroyed.
33 * @param aTransaction the transaction to do.
35 void doTransaction
(in nsITransaction aTransaction
);
38 * Pops the topmost transaction on the undo stack, calls its
39 * undoTransaction() method, then pushes it on the redo stack.
41 void undoTransaction
();
44 * Pops the topmost transaction on the redo stack, calls its
45 * redoTransaction() method, then pushes it on the undo stack.
47 void redoTransaction
();
50 * Clears the undo and redo stacks.
55 * Clears the undo stack only.
57 void clearUndoStack
();
60 * Clears the redo stack only.
62 void clearRedoStack
();
65 * Turns on the transaction manager's batch mode, forcing all transactions
66 * executed by the transaction manager's doTransaction() method to be
67 * aggregated together until EndBatch() is called. This mode allows an
68 * application to execute and group together several independent transactions
69 * so they can be undone with a single call to undoTransaction().
70 * @param aData An arbitrary nsISupports object that is associated with the
71 * batch. Can be retrieved from nsITransactionList.
73 void beginBatch
(in nsISupports aData
);
76 * Turns off the transaction manager's batch mode.
77 * @param aAllowEmpty If true, a batch containing no children will be
78 * pushed onto the undo stack. Otherwise, ending a batch with no
79 * children will result in no transactions being pushed on the undo stack.
81 void endBatch
(in boolean aAllowEmpty
);
84 * The number of items on the undo stack.
86 readonly attribute
long numberOfUndoItems
;
89 * The number of items on the redo stack.
91 readonly attribute
long numberOfRedoItems
;
94 * Sets the maximum number of transaction items the transaction manager will
95 * maintain at any time. This is commonly referred to as the number of levels
97 * @param aMaxCount A value of -1 means no limit. A value of zero means the
98 * transaction manager will execute each transaction, then immediately release
99 * all references it has to the transaction without pushing it on the undo
100 * stack. A value greater than zero indicates the max number of transactions
101 * that can exist at any time on both the undo and redo stacks. This method
102 * will prune the necessary number of transactions on the undo and redo
103 * stacks if the value specified is less than the number of items that exist
104 * on both the undo and redo stacks.
106 attribute
long maxTransactionCount
;
109 * Combines the transaction at the top of the undo stack (if any) with the
110 * preceding undo transaction (if any) into a batch transaction. Thus,
111 * a call to undoTransaction() will undo both transactions.
116 * Removes the transaction at the top of the undo stack (if any) without
119 void removeTopUndo
();
122 * Returns an AddRef'd pointer to the transaction at the top of the
123 * undo stack. Callers should be aware that this method could return
124 * return a null in some implementations if there is a batch at the top
127 nsITransaction peekUndoStack
();
130 * Returns an AddRef'd pointer to the transaction at the top of the
131 * redo stack. Callers should be aware that this method could return
132 * return a null in some implementations if there is a batch at the top
135 nsITransaction peekRedoStack
();
138 * Returns the list of transactions on the undo stack. Note that the
139 * transaction at the top of the undo stack will actually be at the
140 * index 'n-1' in the list, where 'n' is the number of items in the list.
142 nsITransactionList getUndoList
();
145 * Returns the list of transactions on the redo stack. Note that the
146 * transaction at the top of the redo stack will actually be at the
147 * index 'n-1' in the list, where 'n' is the number of items in the list.
149 nsITransactionList getRedoList
();
152 * Adds a listener to the transaction manager's notification list. Listeners
153 * are notified whenever a transaction is done, undone, or redone.
155 * The listener's AddRef() method is called.
156 * @param aListener the lister to add.
158 void AddListener
(in nsITransactionListener aListener
);
161 * Removes a listener from the transaction manager's notification list.
163 * The listener's Release() method is called.
164 * @param aListener the lister to remove.
166 void RemoveListener
(in nsITransactionListener aListener
);