75 lines
2.5 KiB
C
75 lines
2.5 KiB
C
|
/****************************************************************************
|
||
|
|
** Copyright (C) 2001-2011 Klaralvdalens Datakonsult AB. All rights reserved.
|
||
|
|
**
|
||
|
|
** This file is part of the KD Chart library.
|
||
|
|
**
|
||
|
|
** Licensees holding valid commercial KD Chart licenses may use this file in
|
||
|
|
** accordance with the KD Chart Commercial License Agreement provided with
|
||
|
|
** the Software.
|
||
|
|
**
|
||
|
|
**
|
||
|
|
** This file may be distributed and/or modified under the terms of the
|
||
|
|
** GNU General Public License version 2 and version 3 as published by the
|
||
|
|
** Free Software Foundation and appearing in the file LICENSE.GPL.txt included.
|
||
|
|
**
|
||
|
|
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
|
||
|
|
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
|
||
|
|
**
|
||
|
|
** Contact info@kdab.com if any conditions of this licensing are not
|
||
|
|
** clear to you.
|
||
|
|
**
|
||
|
|
**********************************************************************/
|
||
|
|
|
||
|
|
#ifndef KDCHARTSIGNALCOMPRESSOR_H
|
||
|
|
#define KDCHARTSIGNALCOMPRESSOR_H
|
||
|
|
|
||
|
|
#include <QObject>
|
||
|
|
#include <QTimer>
|
||
|
|
|
||
|
|
namespace KDChart {
|
||
|
|
|
||
|
|
/** SignalCompressor compresses signals where the same signal
|
||
|
|
needs to be emitted by several pieces of the code, but only
|
||
|
|
one of the signals should be received at the end.
|
||
|
|
Usage:
|
||
|
|
* create a object of SignalCompressor, and give it the name
|
||
|
|
and object of the signal it is supposed to manage
|
||
|
|
* instead of emitting the signal, call emitSignal() on the compressor
|
||
|
|
* the signal will only be emitted once, and that is after the
|
||
|
|
current call stack ends and returns to the event loop
|
||
|
|
|
||
|
|
With the current implementation, the class changes the
|
||
|
|
sematics of signals to be a queued connection. If that is not
|
||
|
|
wanted, another compression algorithm needs to be
|
||
|
|
implemented.
|
||
|
|
Also, at the moment, only nullary signals are supported, as
|
||
|
|
parameters could not be compressed.
|
||
|
|
A typical use of the class is to compress update
|
||
|
|
notifications.
|
||
|
|
This class is not part of the published KDChart API.
|
||
|
|
*/
|
||
|
|
class SignalCompressor : public QObject
|
||
|
|
{
|
||
|
|
Q_OBJECT
|
||
|
|
|
||
|
|
public:
|
||
|
|
SignalCompressor( QObject* receiver, const char* signal,
|
||
|
|
QObject* parent = 0 );
|
||
|
|
|
||
|
|
Q_SIGNALS:
|
||
|
|
void finallyEmit();
|
||
|
|
|
||
|
|
public Q_SLOTS:
|
||
|
|
void emitSignal(); // emit() won't work, because of stupid defines
|
||
|
|
|
||
|
|
private Q_SLOTS:
|
||
|
|
void nowGoAlready();
|
||
|
|
|
||
|
|
private:
|
||
|
|
QTimer m_timer;
|
||
|
|
};
|
||
|
|
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif
|