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0001 /* 0002 * Copyright (C) 2001-2015 Klaralvdalens Datakonsult AB. All rights reserved. 0003 * 0004 * This file is part of the KD Chart library. 0005 * 0006 * This program is free software; you can redistribute it and/or 0007 * modify it under the terms of the GNU General Public License as 0008 * published by the Free Software Foundation; either version 2 of 0009 * the License, or (at your option) any later version. 0010 * 0011 * This program is distributed in the hope that it will be useful, 0012 * but WITHOUT ANY WARRANTY; without even the implied warranty of 0013 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 0014 * GNU General Public License for more details. 0015 * 0016 * You should have received a copy of the GNU General Public License 0017 * along with this program. If not, see <https://www.gnu.org/licenses/>. 0018 */ 0019 0020 #ifndef KCHARTPAINTERSAVER_P_H 0021 #define KCHARTPAINTERSAVER_P_H 0022 0023 // 0024 // W A R N I N G 0025 // ------------- 0026 // 0027 // This file is not part of the KD Chart API. It exists purely as an 0028 // implementation detail. This header file may change from version to 0029 // version without notice, or even be removed. 0030 // 0031 // We mean it. 0032 // 0033 0034 #include "KChartMath_p.h" 0035 0036 #include <qpainter.h> 0037 0038 0039 namespace KChart { 0040 0041 /** 0042 \internal 0043 0044 @short Resource Allocation Is Initialization for QPainter::save and 0045 restore 0046 0047 Usage: 0048 0049 Instead of 0050 \code 0051 painter.save(); 0052 // ... 0053 painter.restore(); 0054 \endcode 0055 0056 Use this: 0057 0058 \code 0059 const KChart::PainterSaver saver( &painter ); 0060 // ... 0061 \endcode 0062 0063 which makes sure that restore() is called when exiting from guard 0064 clauses, or when exceptions are thrown. 0065 */ 0066 class PainterSaver { 0067 Q_DISABLE_COPY( PainterSaver ) 0068 public: 0069 explicit PainterSaver( QPainter* p ) 0070 : painter( p ) 0071 { 0072 #if defined Q_OS_WIN 0073 static bool initialized = false; 0074 static bool isQt4_3_0; 0075 if ( !initialized ) 0076 { 0077 isQt4_3_0 = ( QString::fromLatin1( qVersion() ) == QString::fromLatin1( "4.3.0" ) ); 0078 } 0079 initialized = true; 0080 m_isQt4_3_0 = isQt4_3_0; 0081 #endif 0082 p->save(); 0083 } 0084 0085 ~PainterSaver() 0086 { 0087 #if defined Q_OS_WIN 0088 // the use of setClipRect is a workaround for a bug in Qt 4.3.0 which could 0089 // lead to an assert on Windows 0090 if ( m_isQt4_3_0 ) 0091 { 0092 painter->setClipRect( 0, 0, 2, 2 ); 0093 } 0094 #endif 0095 painter->restore(); 0096 } 0097 0098 private: 0099 #if defined Q_OS_WIN 0100 bool m_isQt4_3_0; 0101 #endif 0102 QPainter* const painter; 0103 }; 0104 0105 } 0106 0107 #endif /* KCHARTPAINTERSAVER_P_H */ 0108