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/****************************************************************************
**
** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples 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 Nokia Corporation 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 <QtGui>
#include "circlewidget.h"
#include <stdlib.h>
//! [0]
CircleWidget::CircleWidget(QWidget *parent)
: QWidget(parent)
{
floatBased = false;
antialiased = false;
frameNo = 0;
setBackgroundRole(QPalette::Base);
setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
}
//! [0]
//! [1]
void CircleWidget::setFloatBased(bool floatBased)
{
this->floatBased = floatBased;
update();
}
//! [1]
//! [2]
void CircleWidget::setAntialiased(bool antialiased)
{
this->antialiased = antialiased;
update();
}
//! [2]
//! [3]
QSize CircleWidget::minimumSizeHint() const
{
return QSize(50, 50);
}
//! [3]
//! [4]
QSize CircleWidget::sizeHint() const
{
return QSize(180, 180);
}
//! [4]
//! [5]
void CircleWidget::nextAnimationFrame()
{
++frameNo;
update();
}
//! [5]
//! [6]
void CircleWidget::paintEvent(QPaintEvent *)
{
QPainter painter(this);
painter.setRenderHint(QPainter::Antialiasing, antialiased);
painter.translate(width() / 2, height() / 2);
//! [6]
//! [7]
for (int diameter = 0; diameter < 256; diameter += 9) {
int delta = abs((frameNo % 128) - diameter / 2);
int alpha = 255 - (delta * delta) / 4 - diameter;
//! [7] //! [8]
if (alpha > 0) {
painter.setPen(QPen(QColor(0, diameter / 2, 127, alpha), 3));
if (floatBased) {
painter.drawEllipse(QRectF(-diameter / 2.0, -diameter / 2.0,
diameter, diameter));
} else {
painter.drawEllipse(QRect(-diameter / 2, -diameter / 2,
diameter, diameter));
}
}
}
}
//! [8]
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