1 | /* |
2 | Copyright (c) 2007 Volker Krause <vkrause@kde.org> |
3 | |
4 | This library is free software; you can redistribute it and/or modify it |
5 | under the terms of the GNU Library General Public License as published by |
6 | the Free Software Foundation; either version 2 of the License, or (at your |
7 | option) any later version. |
8 | |
9 | This library is distributed in the hope that it will be useful, but WITHOUT |
10 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
11 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public |
12 | License for more details. |
13 | |
14 | You should have received a copy of the GNU Library General Public License |
15 | along with this library; see the file COPYING.LIB. If not, write to the |
16 | Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
17 | 02110-1301, USA. |
18 | */ |
19 | |
20 | #ifndef AKONADI_CHANGERECORDER_H |
21 | #define AKONADI_CHANGERECORDER_H |
22 | |
23 | #include <akonadi/monitor.h> |
24 | |
25 | class QSettings; |
26 | |
27 | namespace Akonadi { |
28 | |
29 | class ChangeRecorderPrivate; |
30 | |
31 | /** |
32 | * @short Records and replays change notification. |
33 | * |
34 | * This class is responsible for recording change notifications while |
35 | * an agent is not online and replaying the notifications when the agent |
36 | * is online again. Therefore the agent doesn't have to care about |
37 | * online/offline mode in its synchronization algorithm. |
38 | * |
39 | * Unlike Akonadi::Monitor this class only emits one change signal at a |
40 | * time. To receive the next one you need to explicitly call replayNext(). |
41 | * If a signal is emitted that has no receivers, it's automatically skipped, |
42 | * which means you only need to connect to signals you are actually interested |
43 | * in. |
44 | * |
45 | * @author Volker Krause <vkrause@kde.org> |
46 | */ |
47 | class AKONADI_EXPORT ChangeRecorder : public Monitor |
48 | { |
49 | Q_OBJECT |
50 | public: |
51 | /** |
52 | * Creates a new change recorder. |
53 | */ |
54 | explicit ChangeRecorder(QObject *parent = 0); |
55 | |
56 | /** |
57 | * Destroys the change recorder. |
58 | * All not yet processed changes are written back to the config file. |
59 | */ |
60 | ~ChangeRecorder(); |
61 | |
62 | /** |
63 | * Sets the QSettings object used for persistent recorded changes. |
64 | */ |
65 | void setConfig(QSettings *settings); |
66 | |
67 | /** |
68 | * Returns whether there are recorded changes. |
69 | */ |
70 | bool isEmpty() const; |
71 | |
72 | /** |
73 | * Removes the previously emitted change from the records. |
74 | */ |
75 | void changeProcessed(); |
76 | |
77 | /** |
78 | * Enables change recording. If change recording is disabled, this class |
79 | * behaves exactly like Akonadi::Monitor. |
80 | * Change recording is enabled by default. |
81 | * @param enable @c false to disable change recording. @c true by default |
82 | */ |
83 | void setChangeRecordingEnabled(bool enable); |
84 | |
85 | /** |
86 | * Debugging: dump current list of notifications, as saved on disk. |
87 | */ |
88 | QString dumpNotificationListToString() const; |
89 | |
90 | public Q_SLOTS: |
91 | /** |
92 | * Replay the next change notification and erase the previous one from the record. |
93 | */ |
94 | void replayNext(); |
95 | |
96 | Q_SIGNALS: |
97 | /** |
98 | * Emitted when new changes are recorded. |
99 | */ |
100 | void changesAdded(); |
101 | |
102 | /** |
103 | * Emitted when replayNext() was called, but there was no valid change to replay. |
104 | * This can happen when all pending changes have been filtered out, for example. |
105 | * You only need to connect to this signal if you rely on one signal being emitted |
106 | * as a result of calling replayNext(). |
107 | */ |
108 | void nothingToReplay(); |
109 | |
110 | protected: |
111 | //@cond PRIVATE |
112 | explicit ChangeRecorder(ChangeRecorderPrivate *d, QObject *parent = 0); |
113 | //@endcond |
114 | |
115 | private: |
116 | //@cond PRIVATE |
117 | Q_DECLARE_PRIVATE(ChangeRecorder) |
118 | //@endcond |
119 | }; |
120 | |
121 | } |
122 | |
123 | #endif |
124 | |