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/****************************************************************************
**
** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** You may use this file under the terms of the BSD license as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
** distribution.
** * Neither the name of Digia Plc and its Subsidiary(-ies) nor the names
** of its contributors may be used to endorse or promote products derived
** from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include <qapplication.h>
#include <qlabel.h>
#include <qpixmap.h>
#include <qprinter.h>
#include <qpainter.h>
#include <qfile.h>
#include <qdir.h>
#include <qfileinfo.h>
#include <QtGui>
#include <QtCore>
class MyClass : public QWidget
{
public:
MyClass(QWidget *parent = 0) : QWidget(parent) { }
protected:
void paintEvent(QPaintEvent *e)
{
/*QRadialGradient rg(50, 50, 50, 50, 50);
rg.setColorAt(0, QColor::fromRgbF(1, 0, 0, 1));
rg.setColorAt(1, QColor::fromRgbF(0, 0, 0, 0));
QPainter pmp(&pm);
pmp.fillRect(0, 0, 100, 100, rg);
pmp.end();*/
createImage();
QPainter p(this);
p.fillRect(rect(), Qt::white);
p.drawPixmap(0, 0, pixmap);
p.drawPixmap(100, 0, channelImage);
}
void createImage()
{
//! [0]
pixmap = QPixmap(100, 100);
pixmap.fill(Qt::transparent);
QRadialGradient gradient(50, 50, 50, 50, 50);
gradient.setColorAt(0, QColor::fromRgbF(1, 0, 0, 1));
gradient.setColorAt(1, QColor::fromRgbF(0, 0, 0, 0));
QPainter painter(&pixmap);
painter.fillRect(0, 0, 100, 100, gradient);
channelImage = pixmap.alphaChannel();
update();
//! [0]
}
QPixmap channelImage, pixmap;
QSize sizeHint() const { return QSize(500, 500); }
};
int main(int argc, char **argv)
{
QApplication app(argc, argv);
MyClass cl;
cl.show();
QObject::connect(&app, SIGNAL(lastWindowClosed()), &app, SLOT(quit()));
int ret = app.exec();
return ret;
}
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