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/****************************************************************************
**
** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia. For licensing terms and
** conditions see http://qt.digia.com/licensing. For further information
** use the contact form at http://qt.digia.com/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Digia gives you certain additional
** rights. These rights are described in the Digia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
#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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