Long live Qt 4.5!

1 files changed, 129 insertions, 0 deletions

diff --git a/doc/src/snippets/myscrollarea.cpp b/doc/src/snippets/myscrollarea.cpp
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+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Qt Software Information (qt-info@nokia.com)
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the either Technology Preview License Agreement or the
+** Beta Release License Agreement.
+**
+** 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, Nokia gives you certain
+** additional rights. These rights are described in the Nokia Qt LGPL
+** Exception version 1.0, 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.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at qt-sales@nokia.com.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtGui>
+
+class MyScrollArea : public QAbstractScrollArea
+{
+public:
+    MyScrollArea(QWidget *w);
+    void setWidget(QWidget *w);
+
+protected:
+    void scrollContentsBy(int dx, int dy);
+    void resizeEvent(QResizeEvent *event);
+
+private:
+    void updateWidgetPosition();
+    void updateArea();
+
+    QWidget *widget;
+};
+
+MyScrollArea::MyScrollArea(QWidget *widget)
+    : QAbstractScrollArea()
+{
+    setWidget(widget);
+}
+
+void MyScrollArea::setWidget(QWidget *w)
+{
+    widget = w;
+    widget->setParent(viewport());
+    if (!widget->testAttribute(Qt::WA_Resized))
+        widget->resize(widget->sizeHint());
+
+    verticalScrollBar()->setValue(0);
+    verticalScrollBar()->setValue(0);
+
+    updateArea();
+}
+
+void MyScrollArea::updateWidgetPosition()
+{
+//! [0]
+    int hvalue = horizontalScrollBar()->value();
+    int vvalue = verticalScrollBar()->value();
+    QPoint topLeft = viewport()->rect().topLeft();
+
+    widget->move(topLeft.x() - hvalue, topLeft.y() - vvalue);
+//! [0]
+}
+
+void MyScrollArea::scrollContentsBy(int /*dx*/, int /*dy*/)
+{
+    updateWidgetPosition();
+}
+
+void MyScrollArea::updateArea()
+{
+//! [1]
+    QSize areaSize = viewport()->size();
+    QSize  widgetSize = widget->size();
+
+    verticalScrollBar()->setPageStep(widgetSize.height());
+    horizontalScrollBar()->setPageStep(widgetSize.width());
+    verticalScrollBar()->setRange(0, widgetSize.height() - areaSize.height());
+    horizontalScrollBar()->setRange(0, widgetSize.width() - areaSize.width());
+    updateWidgetPosition();
+//! [1]
+}
+
+void MyScrollArea::resizeEvent(QResizeEvent *event)
+{
+    updateArea();
+}
+
+int main(int argv, char **args)
+{
+    QApplication app(argv, args);
+
+    QPixmap pixmap("mypixmap.png");
+    QLabel label;
+    label.setPixmap(pixmap);
+    MyScrollArea area(&label);
+    area.resize(300, 300);
+    area.show();
+    
+    area.setWidget(&label);
+
+    return app.exec();
+}