summaryrefslogtreecommitdiffstats
path: root/src/gvcore/busylevelmanager.h
blob: d1f22e140e6231b6e416fd9226a5dc17f2f39bed (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
/*
Gwenview - A simple image viewer for TDE
Copyright 2000-2004 Aurélien Gâteau
 
 This program is free software; you can redistribute it and/or
 modify it under the terms of the GNU General Public License
 as published by the Free Software Foundation; either version 2
 of the License, or (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

*/
#ifndef BUSYLEVELMANAGER_H
#define BUSYLEVELMANAGER_H

// TQt
#include <tqtimer.h>
namespace Gwenview {

// KDE
#include "libgwenview_export.h"

/*
 Busy level of the application.
 Sorted by increasing priority.
*/
enum BusyLevel {
	BUSY_NONE,
	BUSY_THUMBNAILS,
	BUSY_PRELOADING,
	BUSY_LOADING,
	BUSY_SMOOTHING,
	BUSY_PAINTING,
	BUSY_CHECKING_NEW_IMAGE
};

class LIBGWENVIEW_EXPORT BusyLevelManager : public TQObject {
TQ_OBJECT
  
public:
	static BusyLevelManager* instance();

	/**
	 * Announces that the given object is busy.
	 */
	void setBusyLevel( TQObject* obj, BusyLevel level );

	/**
	 * Returns the busy level of the whole application (i.e. maximum).
	 */
	BusyLevel busyLevel() const;

signals:
	/**
	 * When emitted, operations that are less important than current level
	 * should be suspended until the level decreases to their level.
	 * E.g. when loading a picture thumbnail generation should get suspended.
	 */
	void busyLevelChanged( BusyLevel level );

private slots:
	void delayedBusyLevelChanged();
	void objectDestroyed( TQObject* obj );

private:
	BusyLevelManager();
	TQMap< TQObject*, BusyLevel > mBusyLevels;
	BusyLevel mCurrentBusyLevel;
	TQTimer mDelayedBusyLevelTimer;
};


/**
  Helper class. Constructor sets its busy level to the given level,
  destructor resets the busy level to none.
 */
class BusyLevelHelper : public TQObject {
TQ_OBJECT
  
public:
	BusyLevelHelper( BusyLevel level );
	~BusyLevelHelper();
	void reset();
};

inline
BusyLevelHelper::BusyLevelHelper( BusyLevel level )
{
	BusyLevelManager::instance()->setBusyLevel( this, level );
}

inline
void BusyLevelHelper::reset()
{
	BusyLevelManager::instance()->setBusyLevel( this, BUSY_NONE );
}

inline
BusyLevelHelper::~BusyLevelHelper()
{
	reset();
}


} // namespace
#endif