/****************************************************************************+
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**+
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** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).+
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** All rights reserved.+
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** Contact: Nokia Corporation (qt-info@nokia.com)+
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**+
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** This file is part of the documentation of the Qt Toolkit.+
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**+
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** $QT_BEGIN_LICENSE:LGPL$+
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** No Commercial Usage+
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** This file contains pre-release code and may not be distributed.+
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** You may use this file in accordance with the terms and conditions+
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** contained in the Technology Preview License Agreement accompanying+
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** this package.+
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**+
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** GNU Lesser General Public License Usage+
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** Alternatively, this file may be used under the terms of the GNU Lesser+
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** General Public License version 2.1 as published by the Free Software+
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** Foundation and appearing in the file LICENSE.LGPL included in the+
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** packaging of this file.  Please review the following information to+
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** ensure the GNU Lesser General Public License version 2.1 requirements+
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** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.+
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**+
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** In addition, as a special exception, Nokia gives you certain additional+
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** rights.  These rights are described in the Nokia Qt LGPL Exception+
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** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.+
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**+
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** If you have questions regarding the use of this file, please contact+
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** Nokia at qt-info@nokia.com.+
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**+
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**+
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**+
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**+
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**+
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**+
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**+
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**+
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** $QT_END_LICENSE$+
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**+
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****************************************************************************/+
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+
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#include <QtGui>+
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+
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class MyScrollArea : public QAbstractScrollArea+
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{+
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public:+
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    MyScrollArea(QWidget *w);+
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    void setWidget(QWidget *w);+
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+
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protected:+
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    void scrollContentsBy(int dx, int dy);+
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    void resizeEvent(QResizeEvent *event);+
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+
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private:+
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    void updateWidgetPosition();+
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    void updateArea();+
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+
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    QWidget *widget;+
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};+
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+
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MyScrollArea::MyScrollArea(QWidget *widget)+
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    : QAbstractScrollArea()+
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{+
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    setWidget(widget);+
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}+
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+
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void MyScrollArea::setWidget(QWidget *w)+
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{+
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    widget = w;+
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    widget->setParent(viewport());+
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    if (!widget->testAttribute(Qt::WA_Resized))+
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        widget->resize(widget->sizeHint());+
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+
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    verticalScrollBar()->setValue(0);+
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    verticalScrollBar()->setValue(0);+
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+
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    updateArea();+
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}+
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+
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void MyScrollArea::updateWidgetPosition()+
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{+
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//! [0]+
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    int hvalue = horizontalScrollBar()->value();+
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    int vvalue = verticalScrollBar()->value();+
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    QPoint topLeft = viewport()->rect().topLeft();+
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+
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    widget->move(topLeft.x() - hvalue, topLeft.y() - vvalue);+
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//! [0]+
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}+
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+
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void MyScrollArea::scrollContentsBy(int /*dx*/, int /*dy*/)+
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{+
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    updateWidgetPosition();+
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}+
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+
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void MyScrollArea::updateArea()+
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{+
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//! [1]+
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    QSize areaSize = viewport()->size();+
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    QSize  widgetSize = widget->size();+
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+
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    verticalScrollBar()->setPageStep(widgetSize.height());+
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    horizontalScrollBar()->setPageStep(widgetSize.width());+
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    verticalScrollBar()->setRange(0, widgetSize.height() - areaSize.height());+
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    horizontalScrollBar()->setRange(0, widgetSize.width() - areaSize.width());+
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    updateWidgetPosition();+
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//! [1]+
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}+
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+
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void MyScrollArea::resizeEvent(QResizeEvent *event)+
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{+
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    updateArea();+
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}+
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+
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int main(int argv, char **args)+
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{+
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    QApplication app(argv, args);+
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+
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    QPixmap pixmap("mypixmap.png");+
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    QLabel label;+
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    label.setPixmap(pixmap);+
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    MyScrollArea area(&label);+
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    area.resize(300, 300);+
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    area.show();+
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    +
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    area.setWidget(&label);+
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+
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    return app.exec();+
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}+
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