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Diffstat (limited to 'doc/src/snippets/myscrollarea.cpp')
-rw-r--r-- | doc/src/snippets/myscrollarea.cpp | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/doc/src/snippets/myscrollarea.cpp b/doc/src/snippets/myscrollarea.cpp new file mode 100644 index 0000000000..93b487d317 --- /dev/null +++ b/doc/src/snippets/myscrollarea.cpp @@ -0,0 +1,128 @@ +/**************************************************************************** +** +** 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 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 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> + +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(); +} |